U.S. patent application number 12/477534 was filed with the patent office on 2010-12-09 for multi-source projection-type display.
This patent application is currently assigned to HONEYWOOD TECHNOLOGIES, LLC. Invention is credited to William J. Plut.
Application Number | 20100309391 12/477534 |
Document ID | / |
Family ID | 42357857 |
Filed Date | 2010-12-09 |
United States Patent
Application |
20100309391 |
Kind Code |
A1 |
Plut; William J. |
December 9, 2010 |
MULTI-SOURCE PROJECTION-TYPE DISPLAY
Abstract
A display device capable of displaying a plurality of projection
images is provided. The display device includes a light source
within a base and a plurality of projection outputs. Each
projection output comprises an optical modulation device and a
projection lens system. The light source includes a switch and a
plurality of light sources such as lasers or LEDs with different
color to one another. The switch receives and diverts light beams
from the light sources in a predetermined sequential order to the
plurality of projection outputs.
Inventors: |
Plut; William J.; (Los
Altos, CA) |
Correspondence
Address: |
TUROCY & WATSON, LLP
127 Public Square, 57th Floor, Key Tower
CLEVELAND
OH
44114
US
|
Assignee: |
HONEYWOOD TECHNOLOGIES, LLC
Los Altos
CA
|
Family ID: |
42357857 |
Appl. No.: |
12/477534 |
Filed: |
June 3, 2009 |
Current U.S.
Class: |
348/756 ;
345/1.3; 348/E5.139; 353/31; 353/94 |
Current CPC
Class: |
H04N 9/3117 20130101;
H04N 9/3147 20130101 |
Class at
Publication: |
348/756 ; 353/94;
345/1.3; 353/31; 348/E05.139 |
International
Class: |
H04N 5/74 20060101
H04N005/74; G03B 21/14 20060101 G03B021/14; G09G 5/12 20060101
G09G005/12; G02F 1/00 20060101 G02F001/00 |
Claims
1. A system configured to facilitate projection display of an
image, comprising: a switching component configured to receive
light from a plurality of light sources; and a multi-output
projection component comprising a plurality of projection outputs,
wherein the switching component is configured to direct a portion
of the light to an appropriate one of the plurality of projection
outputs, and the multi-output projection component is configured to
cast multiple images using the portion of the light and video data
via more than one of the appropriate one of the projection outputs
onto a plurality of projection areas as a function of video
data.
2. The system of claim 1, further comprising: a controller coupled
to the switching component configured to control the switching
component to sequentially direct the portion of the light to a
different one of the plurality of projection outputs.
3. The system of claim 1, wherein the controller controls the
switching component to sequentially direct the portion of the light
to each of the plurality of projection outputs for substantially
the same amount of time before switching to the next projection
output.
4. The system of claim 1, wherein the controller controls the
switching component to sequentially direct the portion of the light
to each of the plurality of projection outputs for variable amounts
of time before switching to the next projection output based on at
least one system parameter.
5. The system of claim 1, further comprising a plurality of
modulators, wherein each of the modulators is configured to
facilitate the projection of the portion of light.
6. The system of claim 1, wherein each of the plurality of light
sources includes a laser-based light source.
7. The system of claim 1, wherein each of the plurality of light
sources includes a light emitting diode (LED).
8. The system of claim 1, wherein the plurality of projection areas
are located upon a single planar surface.
9. The system of claim 1, wherein the plurality of projection areas
are located upon at least two surfaces.
10. The system of claim 9, wherein the at least two surfaces
comprise at least two of a wall, floor, or ceiling surface.
11. The system of claim 1, further comprising a controller
configured to align each of the outputs upon each of the plurality
of projection areas based at least in part upon video data.
12. The system of claim 1, further comprising a controller that
adjusts resolution of each of the outputs upon each of the
plurality of projection areas.
13. A display device, comprising: a light source configured to
generate light, wherein the light source comprises a switch and a
plurality of color light sets, wherein each color light set is
configured to generate a light beam having a color which is
different than a color of the light beam generated by the other
color light sets; and a plurality of projection outputs, wherein
the switch is configured to receive each light beam and to divert
each light beam in a predetermined sequential order to at least one
of the plurality of projection outputs.
14. The device of claim 13, wherein each of the projection outputs
comprises: an optical modulation device configured to selectively
transmit light generated by the light source according to video
data included in a video signal provided to the optical modulation
device, and a projection lens system configured to output light
transmitted by the optical modulation device along a projection
path to form a projection image on an external receiving
surface.
15. The display device of claim 14, further comprising: a base for
containing the light source; and a plurality of positional
interfaces configured to allow a plurality of projection outputs to
be moved relative to the base, wherein each of the plurality of
positional interfaces is coupled to the base and to a projection
output in the plurality of projection outputs.
16. The display device of claim 14, further comprising a plurality
of fiber optic cables configured to couple the switch to the each
of the plurality of light sets.
17. The display device of claim 14, further comprising at least one
fiber optic cables configured to couple the switch to the optical
modulation device.
18. The display device of claim 14, further comprising a controller
coupled to the optical modulation device, to the switch, and to the
light source, wherein the controller is configured to sequentially
provide light from the light source to the optical modulation
device using the switch.
19. The display device of claim 18, wherein the controller
comprises a keystone correction tool configured to reduce keystone
distortion of at least one of the projection images, and the device
further comprising an image detector coupled to the controller,
wherein the keystone correction tool is configured to retrieve
information associated with at least one projection image from the
image detector.
20. The display device of claim 14, further comprising a controller
coupled to the optical modulation device and to the light source,
wherein the controller comprises an image coordination tool
configured to coordinate projection images cast by the plurality of
projection outputs.
21. The display device of claim 20, further comprising an image
detector coupled to the controller, wherein the image coordination
tool is configured to retrieve information associated with the
projection images of the plurality of projection outputs from the
image detector.
22. The display device of claim 20, wherein the image coordination
tool comprises a plurality of resolution adjustment instructions
configured to adjust a resolution of at least a portion of the
projection images of the plurality of projection outputs.
23. The display device of claim 20, further comprising an eye
sensor, wherein the image coordination tool comprises an eye
detection module and a plurality of resolution adjustment
instructions, wherein the eye detection module is configured to
retrieve information of a direction of a line of vision from the
eye sensor, and the plurality of resolution adjustment instructions
are configured to adjust a resolution of predetermined portions of
the projection images associated with the direction of the line of
vision.
24. A computer-implemented method of projecting an image,
comprising: employing a processor that executes computer-executable
instructions stored on a computer readable storage medium to
implement the following acts: producing an amount of light via a
plurality of light sources; selectively directing a first portion
of the light to a first optical modulation device; selectively
directing a second portion of the light to a second optical
modulation device; casting the image using the first portion of the
light and the second portion of the light via at least one of the
first optical modulation device or the second optical modulation
device, wherein the casting includes displaying the image in
accordance with video data.
25. The computer-implemented method of claim 24, wherein the
directing of the first portion includes selectively directing the
first portion of the light to the first optical modulation device
for a first time frame; and wherein the directing of the second
portion includes selectively directing the second portion of the
light to the second optical modulation device for a second time
frame, substantially equal to the first time frame.
26. The computer-implemented method of claim 24, wherein the
directing of the first portion includes selectively directing the
first portion of the light to the first optical modulation device
for a predetermined first time frame; and wherein the directing of
the second portion includes selectively directing the second
portion of the light to the second optical modulation device for a
predetermined second time frame, different from the predetermined
first time frame.
27. The computer-implemented method of claim 24, wherein the
casting includes displaying the image in accordance with gaming
video content.
28. The computer-implemented method of claim 27, wherein the
casting includes displaying the image in accordance with gaming
video content of a multimedia console device.
29. The computer-implemented method of claim 27, wherein the
casting includes displaying the image in accordance with gaming
video content of a portable electronic device.
30. The computer-implemented method of claim 24, further comprising
adjusting a resolution of the image.
31. The computer-implemented method of claim 24, further comprising
aligning a plurality of portions of the image.
32. The computer-implemented method of claim 24, wherein the
plurality of light sources are laser-based sources.
33. The computer-implemented method of claim 24, wherein the
plurality of light sources are LED sources.
34. A system for projecting an image, comprising: means for
switching light from a plurality of light sources to a plurality of
projection outputs; and means for configuring the light, wherein
the configured light defines a plurality of images that corresponds
to each of the plurality of projection outputs.
35. The system of claim 34, further comprising means for displaying
each of the plurality of images upon a surface.
36. The system of claim 34, further comprising means for displaying
each of the plurality of images upon a plurality of surfaces.
37. The system of claim 34, further comprising: means for
displaying each of the plurality of images; and means for aligning
each of the plurality of images as a function of the others.
38. The system of claim 37, further comprising means for adjusting
a resolution of a subset of the plurality of images.
39. The system of claim 34, wherein the means for switching light
includes means for sequentially switching from a first mapping of
the plurality of light sources to the plurality of projection
outputs to at least a second mapping of the plurality of light
sources to the plurality of projection outputs.
Description
BACKGROUND
[0001] In general, a projection-type display or video projector
displays an image that corresponds to a video signal upon a
projection screen or other surface (e.g., wall). One of the major
characteristics of projection-type display devices is their ability
to display images that are larger in size than images produced by
other displays such as CRT (cathode-ray tube) or LCD (liquid
crystal display). Projection-type display devices have relatively
smaller size compared to the image capable of being projected.
[0002] Traditionally, these video projection devices are widely
used for business presentations, classroom training, home theater,
etc. For example, projection devices are widely used in many
schools and institutions to project onto an interactive white board
during the course of teaching students.
[0003] Most modern projection devices are capable of correcting
distortion, focus, and other inconsistencies by way of manual
controls. However, to date, conventional projection-type display
devices have been designed in a fixed CRT/LCD traditional mindset,
such as single video output per device, or a lack of portability
for a large image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 illustrates an example system that facilitates
selective projection of images in accordance with aspects of the
innovation.
[0005] FIG. 2 illustrates an example flow chart of procedures that
facilitate multi-image projection in accordance with aspects of the
innovation.
[0006] FIG. 3 illustrates a perspective view of a display device in
accordance with embodiments.
[0007] FIG. 4 is an example schematic chart showing a switch
diverting light beams from light source into different projection
outputs in accordance with embodiments.
[0008] FIG. 5 illustrates a simplified schematic of components
within base of a display device in accordance with embodiments.
[0009] FIG. 6 illustrates simplified front view of an example light
source configuration in accordance with embodiments.
[0010] FIG. 7 illustrates a simplified top perspective view of an
example light source configuration in accordance with
embodiments.
[0011] FIG. 8 shows a simplified side view of projection components
in accordance with aspects of the innovation.
[0012] FIG. 9 illustrates a front view of a projection display
device with positional interface and lower portion cutaway.
[0013] FIG. 10 illustrates a front view of an alternate embodiment
of a projection display device with multiple positional
interfaces.
[0014] FIG. 11 illustrates an alternative perspective view of a
display device in accordance with embodiments.
[0015] FIG. 12 illustrates an alternative schematic chart showing a
switch diverting light beams from light source into different
projection outputs in accordance with embodiments.
[0016] FIGS. 13-16 show various aspects of a display device casting
projection images on a receiving surface in accordance with
embodiments.
[0017] FIGS. 17-18 show various aspects of a display device
projecting three projection images respectively on three receiving
surfaces in accordance embodiments.
[0018] FIG. 19 illustrates an example block diagram of a control
circuitry of display device in accordance with embodiments.
[0019] FIG. 20 illustrates an example visual output according to
embodiments.
[0020] FIG. 21 illustrates another example visual output according
to embodiments.
[0021] FIG. 22 illustrates exemplary, non-limiting embodiments in
which content sensitive determination of foreground and background
content of projected media, such as video game content, enhances a
user experience.
[0022] FIG. 23 illustrates another type of projector module that
can be employed in one or more embodiments.
[0023] FIG. 24 illustrates yet another non-limiting embodiment in
which the type of projector module depicted in FIG. 22 is employed
to achieve switching among multiple outputs.
DETAILED DESCRIPTION
[0024] The innovation is now described with reference to the
drawings, wherein like reference numerals are used to refer to like
elements throughout. In the following description, for purposes of
explanation, numerous specific details are set forth in order to
provide a thorough understanding of the subject innovation. It may
be evident, however, that the innovation may be practiced without
these specific details. In other instances, well-known structures
and devices are shown in block diagram form in order to facilitate
describing the innovation.
[0025] As used in this application, the terms "component" and
"system" are intended to refer to a computer-related entity, either
hardware, a combination of hardware and software, software, or
software in execution. For example, a component may be, but is not
limited to being, a process running on a processor, a processor, an
object, an executable, a thread of execution, a program, and/or a
computer. By way of illustration, both an application running on a
server and the server may be a component. One or more components
may reside within a process and/or thread of execution, and a
component may be localized on one computer and/or distributed
between two or more computers.
[0026] The innovation disclosed and claimed herein, in aspects
thereof, comprises a projection system that displays a plurality of
images upon a single or a plurality of surfaces. In aspects, a
switch is provided that selectively diverts light to each of a
plurality of projection outputs, for example, in accordance with
predetermined video data. The multiple projection outputs enable
multiple images to be displayed upon a single or multiple surfaces
simultaneously.
[0027] Moreover, color wheels have conventionally been used as a
type of analog switch, but are deficiencies inherent to the
switching with color wheels that can cause temporary gaps in the
resulting display that are sometimes noticeable during viewing.
Thus, in accordance with a one non-limiting benefit of one or more
embodiments described herein, digital switching of multiples
colored light output is enabled that does not suffer from the
temporary gaps inherent in analog color wheels. In non-limiting
implementations of multiple outputs, three outputs from three
projection heads are provided in correspondence to three light
sources, e.g., red, green and blue light sources such as light
emitting diodes (LEDs) or lasers.
[0028] In other non-limiting embodiments, a projection apparatus
not only provides digital control of the positioning of multiple
light outputs, but also mechanical control on top of the digital
control of the light outputs. In these embodiments, in addition to
providing digital switching among multiple colored light outputs,
the light outputs can be physically moved by way of mechanical
structure, such as a semi-rigid but bendable structure, to
additionally aim of the colored light outputs. In this way, while
the projection apparatus may be able to handle 60 inch image/video
rendering, a user can adjust the outputs mechanically to achieve a
subset of the total imaging space possible, e.g., such that the
lights outputs cover a 40 inch image/video rendering. Thus, less
than the total imaging space can be realized through the
combination of digital switching of multiple colored light outputs
as well as mechanical maneuverability of the light outputs.
[0029] In other aspects of the subject innovation, the system may
automatically adjust resolution of each (or all) of the displayed
images. In other aspects, multiple image alignment may be adjusted
as appropriate or otherwise desired. In embodiments, keystone
correction may be employed to adjust a displayed image in
accordance with a displayed surface. Similarly, image quality may
be monitored and detected. Accordingly, light sources may be
dynamically controlled as a function of captured data.
[0030] Referring initially to the drawings, FIG. 1 illustrates an
example block diagram of a system 100 that facilitates projection
display in accordance with aspects of the innovation. Generally,
the system 100 may include a projection management system 101 that
enables multiple images to be projected from the projection-type
device 100 as illustrated. Projection management system 101 may
include a switching component 105 and a multi-projection output
component 107 which together facilitate simultaneous projection of
multiple images from a single projection-type display device
100.
[0031] As shown in FIG. 1, the light source may include multiple
sources, for example, a red, green and blue laser set as
illustrated in the example. Red, green and blue light emitting
diode (LED) sets may also be used. The switching component 105 may
direct or route a red laser, the green laser and the blue laser in
a predetermined order to a light modulation device within each
multi-chamber projection component 107. In other words, in one
example, the switching component 105 may direct light in an
alternating, cyclical or other determined order such that each
projection output component 107 may sequentially share light
generated from an individual source. It will be understood that,
while the projection-type display device 100 may employ multiple
projection outputs (107) to generate multiple images, light sources
103 may be shared between the outputs thereby not requiring
dedicated light sources for each projection output.
[0032] FIG. 2 illustrates a methodology of transmitting multiple
images via a projection-type display in accordance with aspects of
the innovation. While, for purposes of simplicity of explanation,
the one or more methodologies shown herein, e.g., in the form of a
flow chart, are shown and described as a series of acts, it is to
be understood and appreciated that the subject innovation is not
limited by the order of acts, as some acts may, in accordance with
the innovation, occur in a different order and/or concurrently with
other acts from that shown and described herein. For example, those
skilled in the art will understand and appreciate that a
methodology could alternatively be represented as a series of
interrelated states or events, such as in a state diagram.
Moreover, not all illustrated acts may be required to implement a
methodology in accordance with the innovation.
[0033] At 202, light is produced via multiple light sources such as
multiple laser sets. In alternative aspects, it is to be understood
that light may be produced via multiple light emitting diodes
(LEDs) or other suitable light source. Video data may be analyzed
at 204, for example, to determine an intended display
configuration. In examples, the innovation may be used to project
multiple images upon a single surface. Alternative, in other
aspects, multiple surfaces may be employed to display multiple
images.
[0034] At 206, light may be diverted to multiple outputs 107 as
described with reference to FIG. 1. In operation, light may be
routed to outputs 107 based upon the analysis of 204. For example,
light may be sequentially transmitted or routed to each of the
outputs 107 in a predetermined manner or timing sequence. It is to
be understood that timing may vary in accordance with most any
sequence or desired presentation scheme.
[0035] At 208, light may be selectively transmitted. For example,
modulation devices within each output may selectively transmit
light in accordance with video data. At 210, the transmitted light
may be output onto a surface or screen. In other aspects, multiple
surfaces or screens may be employed to output or display images. As
described above, multiple projection chambers may be used to
project multiple images from a single projection-type display
device, though chambers are optional in that multiple light outputs
is sufficient. The figures that follow illustrate more detailed
example devices in accordance with the features, functions and
benefits of the innovation. Thus, the innovation will be better
understood upon a review of the disclosure with respect to the
following figures.
[0036] Referring now to FIG. 3, there is illustrated top
perspective view of an example display device 10 in accordance with
one of the present embodiments. Display device 10 is capable of
producing and projecting one or more video images on one or more
receiving surfaces as desired. As shown, device 10 comprises a base
12, a plurality of projection outputs 14 that each include a
separate projection output, and a plurality of positional
interfaces 16.
[0037] Base 12 is configured to maintain a position of display
device 10, e.g., relative to a stationary object. In embodiments,
base 12 includes a relatively flat bottom that allows display
device 10 to rest upon a flat surface such as a table or desk. One
or more high friction pads 18 attach to a bottom surface 22b of
base 12 to increase static friction with the flat surface. Base 12
may also comprise a receiving slot 27 that allows modular
attachment of functional accessories for display device 10. For
example, slot 27 may receive a clip attachment that comprises a
spring-powered clip for clamping base 12 onto a stationary object.
This allows base 12 and display device 10 to be mounted on non-flat
or non-horizontal surfaces such as vertical walls of bookshelves
and cubicles, and personal clothing or accessories such as belts or
straps, for example. Base 12 may also comprise another slot on its
bottom side, dimensioned the same, to permit reception of the
functional accessories on the bottom side of base 12.
[0038] A housing 20 protects internal components within base 12,
defines outer dimensions of base 12, and defines dimensions of an
inner light source output. As shown, housing 20 is about
rectangular and comprises four sidewalls 22c-f (only facing
sidewalls 22c and 22d are shown in the figure), top wall 22a, and
bottom wall 22b. Walls 22 comprise a suitably stiff or rigid
material that grants structural rigidity for base 12 and mechanical
protection for internal components within housing 20. A lightweight
and rigid plastic, composite, alloy or aluminum is suitable in this
regard. One or more walls of housing 20 may also include air vents
24 that allow air flow between the inner chamber and an environment
external to housing 20. In other embodiments, housing 20 includes a
more rounded or contoured shape than that shown in FIG. 3 and does
not include orthogonal walls or a rectangular shape.
[0039] Each projection output 14, such as but not limited to a
projection chamber 14 as presently described, may include
components responsible for the production of images based on
received light and received video data, and components capable for
the projection of those images. Projection chamber 14 comprises a
projection chamber housing 32, an optical modulation device (within
projection chamber housing 32, not shown), and an output projection
lens system (within projection chamber housing 32, not shown). In
accordance with aspects of the innovation, the optical modulation
device selectively transmits light generated by a light source in
base 12 according to video data included in a video signal provided
to the optical modulation device, and will be described in further
detail with respect to the figures that follow. The projection lens
system outputs light transmitted by the optical modulation device
along a projection path, and will also be described in further
detail infra.
[0040] In operation, a light source within base 12 generates light
which is provided to the optical modulation device within
projection chamber 14 as a luminous flux. In embodiments, one or
more optical fibers transmit light from the light source within
base 12 to the optical modulation device within projection chamber
14. The optical modulation device selectively transmits light
according to video data in a signal that corresponds to an image to
be projected. The projection lens system enlarges and projects an
image formed by the optical modulation device. The image is cast
with a splay angle such that the image enlarges as the distance to
a receiving surface increases.
[0041] Projection chamber 14 comprises a projection chamber housing
32 that protects internal components of projection chamber 14; and
defines outer and inner dimensions of projection chamber 14. As
shown, projection chamber housing 32 is substantially cylindrical,
except for an added receiving interface 29 on its bottom side.
Projection chamber housing 32 has a cylindrical axis that is about
collinear with output projection path. An output optical projection
lens 37 of the projection lens system forms and seals forward end
of projection chamber 14.
[0042] In embodiments, the average diameter of cylindrical
projection chamber housing 32 is relatively within ten percent of
the diameter of output optical projection lens 37. In other
embodiments, projection chamber housing 32 tapers slightly such
that its forward end is slightly larger than an aft end, resulting
in a slightly frustoconical shape where lens 37 constitutes the
larger end.
[0043] It is to be understood that the shape and design of
projection chamber 14 may vary in alternative aspects. For example,
forward end of projection chamber 14 may be rounded to accommodate
a circular output lens 37 while aft end is cornered to accommodate
a rectangular optical modulation device and associated support
components that are locally contained better by a rectangular
housing. Projection chamber housing 32 defines an inner chamber as
described in further detail below. Projection chamber housing 32
comprises a suitably stiff material for structural rigidity of base
12 and internal component protection. A lightweight and rigid
plastic, composite, alloy or aluminum is suitable for several
embodiments.
[0044] Receiving interface 29 is disposed on the lower side of
projection chamber 14 and permits coupling between projection
chamber 14 and positional interface 16. Receiving interface 29 also
permits containment and protection of display device 10 components
that do not entirely fit within projection chamber 14, or
components that require spatial arrangements outside of projection
chamber 14. In embodiments, receiving interface 29 comprises the
same material as projection chamber housing 32 and extends the
interior projection chamber provided by projection chamber housing
32.
[0045] Positional interface 16 allows projection chamber 14 to be
moved relative to base 12, and allows projection chamber 14 to
maintain a constant position relative to base 12 after being moved.
Thus, positional interface 16 allows a user to point or aim
projection chamber 14 and manipulate the position of an output
image projected by display device 10 with ease. In embodiments,
positional interface 16 comprises a ball and socket combination
that permits relative rotational movement between projection
chamber 14 and base 12. In other embodiments, positional interface
16 comprises corrugated metal tubing that is sufficiently rigid to
hold a position for projection chamber 14, while compliant enough
for a user to bend the tubing to achieve a desired position and
orientation for projection chamber 14.
[0046] Positional interface 16 couples to base 12 and couples to
projection chamber 14. For the embodiments shown in FIG. 3,
positional interface 16 comprises an upper end that attaches to
projection chamber housing 32 and a lower end that attaches or
couples to housing 20 of base 12. More specifically, a projection
chamber housing 32 portion of receiving interface 29 allows
attachment to upper end of positional interface 16, while a central
portion of top wall 22a allows attachment to lower end of
positional interface 16. As shown, positional interface 16 couples
to projection chamber housing 32 at a location between an aft end
of projection chamber 14 and a forward end that includes output
optical projection lens 37.
[0047] In embodiments, upper end of positional interface 16 couples
at a location relatively close to a center of mass of projection
chamber 14 to minimize mechanical moments transmitted onto base 12,
e.g., those resulting from a displacement of center of mass of
projection chamber 14 away from a center of mass for base 12. In
other embodiments, base 12 includes a recessed groove in top wall
22a that allows positional interface 16 to be folded or collapsed
down into top wall 22a, thereby decreasing the profile of display
device 10 during non-use.
[0048] FIG. 4 illustrates an example schematic chart illustrating
optical path from a light source 64 configured in base 12 (FIG. 3)
to multiple projection outputs 107 such as each projection chamber
14 in accordance with one of the present embodiments. Light source
64 includes a plurality of laser sets, such as a red laser set 961,
a green laser set 962 and a blue laser set 963, generating a
plurality of laser beams with different color to one another, such
as red laser beam, green laser beam and blue laser beam. As shown,
light source 64 may include a switch 8 which receives the red laser
beam, green laser beam and blue laser beam from the red laser set
961, the green laser set 962 and the blue laser set 963
respectively.
[0049] In embodiments, display device 10 comprises three projection
chambers 14. Each of the projection chambers 14 includes an optical
modulation device 102 and a projection lens system 112. The optical
modulation device 102 is configured to selectively transmit light
generated by the light source according to a receiving video data.
The projection lens system 112 is configured to output light
transmitted by the optical modulation device 102 along a
predetermined projection path, so as to display projection images
on one or more external receiving surfaces.
[0050] The switch 8 is capable of diverting the red laser beam, the
green laser beam and the blue laser beam in a predetermined
sequential order to each of the three projection chambers 14. For
instance, in embodiments, there are three modes corresponding to a
first time frame, a second time frame and a third time frame,
respectively.
[0051] In the first mode, during the first time frame, red laser
beam is transmitted from switch 8 to optical modulation device
102a; green laser beam is transmitted from switch 8 to optical
modulation device 102b; blue laser beam is transmitted from switch
8 to optical modulation device 102c.
[0052] In the second mode, during the second time frame, red laser
beam is transmitted from switch 8 to optical modulation device
102c; green laser beam is transmitted from switch 8 to optical
modulation device 102a; blue laser beam is transmitted from switch
8 to optical modulation device 102b.
[0053] In the third mode, during a third time frame, red laser beam
is transmitted from switch 8 to optical modulation device 102b;
green laser beam is transmitted from switch 8 to optical modulation
device 102c; blue laser beam is transmitted from switch 8 to
optical modulation device 102a.
[0054] Lasting time of the first time frame, the second time frame
and the third time frame may be identical to one another in
embodiments. Namely, the first mode, the second mode and the third
mode take turns evenly to be applied in the light source 64. In
some other embodiments, lasting time of the first time frame, the
second time frame and the third time frame may differ from one
another according to system requirement. Such adjustment toward
lasting time may be used as color control manner of the display
device 10.
[0055] FIG. 5 illustrates a simplified top view schematic of
components within base 12 in accordance with some embodiments. A
light source chamber 65 is defined in volume and shape by inside
walls 22a-f of base 12. Light source chamber 65 comprises fans 62a
and 62b, light source 64, power supply 66, fiber-optic interface
70, fiber-optic cable 72, input/output circuitry 74, control
circuitry 76, and input/output interfaces 78.
[0056] In embodiments, base 12 is designed or configured to
maintain balance of display device 10. In this case, base 12 may be
designed to maintain balance for any position of projection chamber
14 relative to base 12 while base 12 rests on a flat surface. Thus,
components within base 12 may be arranged and situated such that
they cumulatively provide a center of mass 23 relatively close to a
geometric center for a footprint of base 12. As shown, light source
64 and power supply 66, which are typically the heaviest components
in base 12, are disposed relatively central to the footprint in one
dimension and on opposite sides of center of mass 23 in the other
dimension. In embodiments, components within base 12 are arranged
within base 12 according to their weight in order to substantially
balance moments about a center of mass 23. The exact position of
each component will depend of on the number and type of components
and base 12 layout. In addition, housing 20 may be sized to provide
a wide enough footprint to balance moments produced by positions
and orientations of projection chamber 14 away from a center of
mass 23 for base 12.
[0057] Fans 62a and 62b move air through light source chamber 65
for cooling components within light source chamber 65. In
embodiments, fans 62a and 62b draw air in through inlet air vents
24a on one side of base 12 and exhaust heated air out of exhaust
air vents 24b after the air has cooled internal components of base
12 and walls of housing 20. One skilled in the art will appreciate
that fans 62a and 62b, inlet air vents 24 and exhaust air vents 24b
placement will vary with internal component placement within light
source chamber 65. Specifically, fan 62a and 62b placement, and
airflow patterns effected by fans 62 within light source chamber
65, is designed according to individual temperature regulation
requirements and heat generation contributions of components within
base 12. Light source 64 and power supply 66 generate the largest
proportion of heat within base 12, while control circuitry 76 and
input/output circuitry 74 call for tighter temperature regulation.
Correspondingly, inlet air 69 passes in through inlet air vents
24a, initially passes and cools control circuitry 76 and
input/output circuitry 74 while the air is relatively cool, passes
across power supply 66 and light source 64, and exits out exhaust
air vents 24b. The exhaust air may also cool fan motors 63a and
63b, which rotate fans 62a and 62b, respectively. In embodiments,
multiple fans are used to permit a lower profile for base 12.
[0058] It is to be understood that the number and size of fans used
will depend on heat generation within display device 10 and a
desired air flow to maintain one or more heat dissipation goals.
Light source chamber 65 may also include one or more vertical or
horizontal airflow guides 67 within light source chamber 65 to
direct and distribute airflow as desired. In embodiments, light
source 64 comprises one or more diode laser arrays and one or more
circuit boards to power and control the diode lasers. In this case,
airflow guides 67 are arranged to direct cooling air across the
surfaces of each circuit board. As will be described in further
detail below, fans 62a and 62b may also be responsible for drawing
air through positional interface 16 and to or from projection
chamber 14 to cool the optical modulation device included
therein.
[0059] FIGS. 6 and 7 illustrate simplified front and top
perspective views, respectively, of a light source configuration in
accordance with some embodiments. In this case, light source
chamber 65 includes an array of lasers that generate collimated
light. Lasers may comprise any combination of diode lasers and/or
diode pumped solid-state (DPSS) lasers, for example. The collimated
light produced by a diode laser differs from radiant light and is
characterized by light that is output with about the same output
direction, and significantly in phase.
[0060] The array of lasers may comprise one or more red diode
lasers 96a, one or more green diode lasers 96b, and one or more
blue diode lasers 96c. A red laser set 961 comprises a plurality of
red diode lasers 96a. A green laser set 962 comprises a plurality
of green DPSS lasers 96b. A blue laser set 963 comprises a
plurality of blue diode lasers 96c. The number and power of lasers
for each color is scaled according to a desired light intensity
output for display device 10 and according to the light sensitivity
of a viewer to each color. Each laser diode is installed on a
circuit board 97, which mounts, and provides electrical control for
each laser diode installed thereon. Multiple lasers may be mounted
on a single board 97 to reduce space occupied by light source 64.
Including multiple lasers for a single color allows output
luminosity of display device 10 to vary with the number of lasers
turned on for each color, and allows for redundant control of light
generation by lasers. Thus, one or more of the lasers may be turned
off if less light intensity is desired, longevity of individual
lasers benefits from periodic shut-down, or power conservation for
display device 10 is preferred.
[0061] Referring to FIG. 8, in embodiments, light output from the
lasers is provided to fiber-optic cabling 72. Fiber-optic cabling
72 includes one or more fiber optic cables that transmit light from
each laser along multiple or common optical paths to relay optics
system 106 and 108 disposed along a light path between an exit end
of fiber-optic cabling 72 and an optical modulation device 102.
[0062] Referring again to FIG. 7, each cable 72 has an inlet end
72a that receives light from a red laser 96a, a green laser 96b or
a blue laser 96c; and each cable 72 also has an outlet end 72b that
outlets the laser light for transmission to relay optics 106 and
108, and subsequent transmission to optical modulation device 102.
Since fiber-optic cabling 72 may be bent and flexibly positioned,
fiber-optic cabling 72 advantageously allows light transmission
between lasers and relay optics system regardless of the
positioning and orientation between the lasers and optics system.
For example, this allows flexible arrangement of lasers, relay
optics 106 and 108 and prism 110 (FIG. 8), which may be used to
improve space conservation within base 12, decrease the footprint
of base 12, and minimize display device 10 size. In addition,
flexible fiber-optic cabling 72 also allows positional interface 16
to move without compromising light provision to the optical
modulation device in projection chamber 14.
[0063] The number of fiber optic cables in cabling 72 will vary
with design. Multiple fiber-optic cables may be employed in a
design where each cable services one or more colors to the switch
and one cable from the switch to each optical modulation device. As
shown in FIG. 7, light from red laser 96a, green laser 96b or blue
laser 96c is first transmitted into a fiber-optic cable dedicated
to each color; and subsequently routed by the switch into a common
fiber-optic cable 71. In embodiments, each fiber-optic cable
attaches directly to an individual laser. For example, each
fiber-optic cable may include a fixture with an inner threaded
interface that matches a threaded interface disposed on an outside
surface of a laser housing. Commercially available fiber-optic
cables, such as that available from Ocean Optics Inc. of Dunedin,
Fla., may come standard with such coupling and alignment fixtures.
In embodiments, a short focal length normal or GRIN lens is mounted
at the inlet end of each cable to facilitate laser-to-fiber light
transition and collimated transfer into cable.
[0064] Junction 75 permits transmission of light from fiber-optic
cables 72 into converging optics 77, and into common fiber-optic
cable 79. Converging optics 77 redirect incoming light from each
fiber-optic cable into common fiber-optic cable 79 and comprise a
converging lens 77a that redirects light toward re-collimating lens
77b, which collimates and re-directs incoming laser light from
converging lens 77a into common optical fiber 79. Although not
shown, junction 75 may also include a rigid structure, such as a
suitably dimensioned molded plastic, that fixtures (e.g., holds and
positions) fiber-optic cables and common fiber-optic cable 79. In
embodiments, junction 75 comprises an optical adhesive that adheres
cables directly to converging lens 77a. In other embodiments, at
the outlet end 72b, the fiber-optic cables are combined into a
larger cable that contains multiple fibers. Multiple fiber cables,
such as fiber ribbon-based cables and those that employ multiple
fibers located circumferentially within a round tube, are
commercially available from a variety of vendors.
[0065] Multiple fiber-optic cable designs may be employed where
each cable transmits a primary color. For example, three
fiber-optic cables may be employed in which each cable transmits
light from a primary color set of lasers along three different
optical paths to three primary colors dedicated optical modulation
devices.
[0066] Referring again to FIG. 5, inner light chamber 65 may also
employ other light source arrangements to generate light for
display device 10. Some light source arrangements, for example, may
comprise an array of radiant light emitting diodes, characterized
by radiant, non-lasing or non-collimated light generation. Similar
to diode and DPSS lasers, radiant light emitting diodes consume
less power and generate less heat than a white light lamp, and also
emit colored light and thereby may operate without a color wheel.
Light chamber 65 may also include one or more dichroic mirrors in
white light generation assemblies to separate red, green and blue
light for transmission within fiber optic cables 72 to color
dedicated optical modulation devices, such as three liquid crystal
display (LCD) valves employed for red, green and blue control.
[0067] Power supply 66 is configured provide to electrical power to
light source 64 and other components within display device 10 that
rely on electrical power. Thus, power supply 66 provides electrical
energy to control circuitry 76, input/output circuitry 74, fans 62a
and 62b, power diode 80 and components within projection chamber 14
such as optical modulation device 102 (FIG. 8). Power diode 80 is
in electrical communication with an external power switch 82 and
may illuminate when display device 10 is turned on to indicate
whether display device 10 is on or off. A power cord port 81
receives a power cord, which couples power supply 66 to an AC power
source such as a wall power supply. In embodiments, conversion of
AC power to DC power occurs in a transformer included between ends
of the power cord, as is common with many laptop computer power
cords, thereby reducing the size of power supply 66, base 12 and
display device 10 and increasing portability of display device 10.
Circuitry within power supply 66 may then convert incoming power to
one or more DC voltages for specific components in display device
10.
[0068] In other embodiments, power supply 66 comprises at least one
rechargeable battery 66a. Battery 66a may be recharged using power
provided through inlet port 81. Battery 66a allows display device
10 to operate on stored energy and without reliance on proximity to
an AC power source, which further increases portability of display
device 10. For example, inclusion of a battery in base 12 extends
usage into a car, library, coffee shop, remote environment, or any
other setting where AC and fixed power outlets are not readily
available or within reach.
[0069] At least one fiber-optic cable 72 transmits light from light
source 64 to relay optics disposed along a light path between an
exit end of fiber-optic cable 72 and optical modulation device 102
(FIG. 8) in projection chamber 14. With respect to device 10
structure, fiber-optic cable 72 transmits light from one
compartment to a separate compartment, namely, from light source
chamber in base 12 to projection chamber 14. The number of fiber
optic cables will vary with design. As mentioned above, multiple
fiber-optic cables may be employed in a laser light generation
design, for example, where each fiber-optic cable 72 services one
or more diode lasers. Alternatively, each fiber-optic cable 72 may
service a primary color. For example, one fiber-optic cable may be
used to transmit sequentially controlled red, green and blue
generated by a diode laser array and transmitted along a single
light path to a single mirror-based optical modulation device.
Three fiber-optic cables may be employed to transmit light from a
laser array that outputs red, green and blue light into three
fiber-optic cables, to three optical modulation devices that are
each dedicated to modulation of a primary color.
[0070] Fiber-optic interface 70 facilitates transmission of light
from each laser into fiber-optic cabling 72. Fiber-optic interface
70 may include one or more fixtures that position and hold an inlet
end for each fiber-optic cable included in fiber-optic cabling 72
such that light output from the light source transmits into a
fiber-optic cable. Fiber-optic interface 70 may also include optics
that direct light from lasers into fiber-optic cabling 72. In
embodiments, a single fiber-optic cable is used in cabling 72 and
fiber-optic interface 70 includes a lens system disposed between
the outlet of a lamp or each laser and the inlet of the single
fiber-optic cable to direct light into the cable. The lens system
may comprise at least two lenses: a first lens to direct the light
towards the fiber entrance and a second lens that collimates light
entering the cable. In other embodiments that implement a
one-to-one laser to fiber-optic cable relationship; fiber-optic
interface 70 holds the inlet end for each fiber-optic cable
relatively close to the outlet of each laser to receive light
therefrom. Each cable in this case may include a converging lens at
its inlet end that facilitates light capture and transmission into
a cable.
[0071] In another one-to-one design, each fiber-optic cable in
fiber-optic cabling 72 includes a fixture that permits attachment
to another object. For example, conventionally available
fiber-optic cables available from vendors such as Ocean Optics Inc.
of Dunedin, Fla. include a detachable fixture with a thread that
allows screwing and fixing of the fiber-optic cable to a mating
thread disposed on a laser housing. In this case, fiber-optic
interface 70 comprises the threaded fixture from each cable and the
mating thread on the laser.
[0072] In some cases, a projection device with multiple outputs may
be operated in single output mode. In single path embodiments where
red, green and blue lasers transmit colored light to a single
optical modulation device along a single fiber-optic cable, switch
105 and fiber-optic interface 70 receives colored light from each
colored laser, in turn, according to timed control signals provided
to the lasers by control circuitry 76.
[0073] Input/output circuitry 74 provides an interface between
control circuitry 76 and one or more input/output interfaces 78.
Input/output interfaces 78 are configured to receive at least one
cable, wire, or connector, such as a cable for transmitting a video
signal comprising video data from a digital computing device.
Common ports suitable for use with input/output interfaces 78
include ports that receive S video cable, 6-pin mini DIN, VGA
15-pin HDDSUB female, an audio cable, component RCA through an
S-Video adaptor, composite video RCA cabling, a universal serial
bus (USB) cable, fire wire, etc. Input/output interfaces 78 may
also include an audio output port for wired connection to speakers
employed by a headphone or speaker system.
[0074] Control circuitry 76 provides control signals to components
of display device 10. In embodiments, control circuitry 76 provides
control signal to components not within base 12 by routing data
from input/output circuitry 74.
[0075] Control circuitry 76 may provide control signals to light
source 64 that determine when light source 64 is turned on/off. In
addition, circuitry 76 may include memory that stores instructions
for the operation of components within display device 10. For
example, circuitry 74 may provide control signals to control fans
24 according to stored heat regulation instructions. One or more
sensors may also be disposed within base 12 to facilitate thermal
regulation. For example, a temperature sensor may be disposed
proximate to circuitry 74 and 76 to monitor temperature levels and
participate in closed loop temperature control within base 12 as
controlled by control circuitry 76.
[0076] Input/output circuitry 74 and input ports 78 collectively
permit communication between display device 10 and a device that
outputs a video signal carrying video data. For example, desktop
computers, laptop computers, personal digital assistants (PDAs),
cellular telephones, video game consoles, digital cameras, digital
video recorders, DVD players, and VCRs, may all be suitable to
output video data to display device 10. Video data provided to
control circuitry 76 may be in an analog or digital form. In some
cases, input/output circuitry 74 and control circuitry 76 convert
analog video signals into digital video signals suitable for
digital control of an optical modulation device included in display
device 10, such as a liquid crystal display "LCD" device or a
digital micromirror "DMD" device. Thus, input/output circuitry 74
or control circuitry 76 may also include support software and logic
for particular connector types, such as processing logic required
for S-video cabling or a digital video signal. Control circuitry 76
may also include and access memory that facilitates conversion of
incoming data types and enhances video compatibility of display
device 10. Suitable video formats having stored conversion
instructions within memory accessed by control circuitry 76 may
include NTSC, PAL, SECAM, EDTV, and HDTV (1080i and 720p RGBHV),
for example.
[0077] When lasers are used for light generation within light
source 64, as described above, control circuitry 76 receives video
data included in a signal via one or more input ports 78 and
input/output circuitry 74, converts the data to color frame
sequential data, and synchronizes the frame sequential data for
delivery to each optical modulation device 102 and to each laser
96. In a single, double or triple path design between lasers 96,
switch, and the optical modulation device where optical fibers
transmit red, green and blue light in a time controlled sequential
order to each optical modulation device, this includes
synchronizing the timing of data sent to the optical modulation
device and on-off commands sent to lasers 96. It is to be
understood that circuitry, e.g., control circuitry, is not intended
to be limited to hardware only. Rather the circuitry, or
controller, is intended to include hardware, software or
combinations of hardware and software.
[0078] FIG. 8 shows a simplified side view illustration of
components within projection chamber 14 of FIG. 3, taken through a
vertical midpoint of chamber 14 along its cylindrical axis, in
accordance with some present embodiments. FIG. 9 shows a front view
illustration of display device 20 with positional interface 16 and
lower projection chamber 29 cutaway to show components therein.
Projection chamber 14 comprises optical modulation device 102,
fiber-optic interface 104, relay optics 106 and 108, prism
structure 110, projection lens system 112, control and power
cabling 120, and air duct 122.
[0079] Fiber-optic cabling 72 attaches to a fiber-optic interface
104 and outputs light to relay optics 106. In embodiments,
fiber-optic interface 104 secures fiber-optic cabling 72 such that
slack is provided for fiber-optic cabling 72 between attachment at
fiber-optic interface 104 and attachment within base 12. The slack
allows fiber-optic cabling 72 to deflect with positional interface
16 for various positions of projection chamber 14 relative to base
12.
[0080] Together, fiber-optic cabling 72 and fiber-optic interface
104 direct light generated by light source 64 to prism 110. In
embodiments, fiber-optic cabling 72 and interface 104 are
configured with respect to prism 110 so as to provide an optical
path of incident light that is about perpendicular to an incident
surface of prism 110. Some digital micro-mirror light modulator
designs require that incoming light be incident on the light
modulator from either above or below its light reflecting surface
to allow light output along projection path 31.
[0081] Receiving interface 29 of projection chamber housing 32 and
fiber-optic interface 104 ease this requirement and allow a
designer to arrange fiber-optic cabling 72 and fiber-optic
interface 104 within receiving interface 29 such that fiber-optic
interface 104 directs light at a particular desired angle relative
to prism 110, and onto optical modulation device 102. For example,
fiber-optic interface 104 may be coupled to receiving interface 29
to provide an incident light path that is perpendicular onto an
incident surface of prism 110 and has a 45 degree angle relative to
optical modulation device 102, e.g., prism 110 is rotated 45
degrees about projection path 31. Attachment between interface 104
and housing 29 maintains the desired incoming light angle despite
changing positions of fiber-optic cabling 72 along its length
caused by repositioning of positional interface 16.
[0082] Relay optics 106 and 108 convert light receive from
fiber-optic cabling 72 to light suitable for transmission into
prism structure 110 and onto optical modulation device 102. This
may include shaping and resizing light flux received from
fiber-optic cabling 72 using one or more lenses.
[0083] In other embodiments, display device 10 comprises a pair of
fly-eye lenses arranged in the optical path between light source 64
and prism 110. Cumulatively, the pair of fly-eye lenses uniformly
distributes light received from fiber-optic cabling 72 to the flux
transmitted upon optical modulation device 102. In embodiments, the
pair of fly-eye lenses are arranged on either and a fiber-optic
cabling 72. The first fly-eye lens is disposed at fiber-optic
interface 70 within base 12, receives light from a lamp or diode
laser array, and spatially divides the entire input light flux into
a set of blocks or components that each comprises a portion of the
total area of the inlet flux. Light for each block or component
then travels down its own fiber-optic cabling 72. The second
fly-eye lens comprises the same number of blocks or components and
is disposed at relay lens 106. The second fly-eye lens receives a
fiber-optic cable for each block or component and outputs light for
each component such that the light from each component is expanded
to span the downstream dimensions of optical modulation device 102
and the projected image.
[0084] Prism structure 110 is an optical modulation system that
provides light to optical modulation device 102 at predetermined
angles. Prism structure 110 also transmits light from optical
modulation device 102 to the projection lens system 112 along
projection path 31. Prism structure 110 comprises prism components
110a and 110b that are separated by air space or bonding interface
110c. Interface 110c is disposed at such an angle so as to reflect
light provided from fiber-optic cables 72, and intermittent relay
optics, towards optical modulation device 102. In addition,
interface 110c allows light reflected by optical modulation device
102 to transmit to projection lens system 112 along projection path
31.
[0085] Optical modulation device 102 is configured to selectively
transmit light to provide an output image along projection path 31.
To do so, optical modulation device 102 is supplied with video data
included in a video signal and selectively transmits light
according to the video data. The video data is typically provided
to device 102 on a frame by frame basis according to individual
pixel values. If the video data is not received by display device
10 in this format, control circuitry 76 in base 12 may convert the
video data to a suitable format for operation of optical modulation
device 102. In embodiments, individual light modulation elements
within optical modulation device 102, which each correspond to an
individual pixel on the output image, translate received digitized
pixel values into corresponding light output values for each
pixel.
[0086] In embodiments, optical modulation device 102 is a mirror
based optical modulation device, such as a digital micro mirror
device (or DMD, a trademark of Texas instruments Inc.) commercially
available from Texas Instruments, Inc. In this case, optical
modulation device 102 comprises a rectangular array of tiny
aluminum micromechanical mirrors, each of which individually
deflects about a hinged axis to selectively reflect output image
light down projection path 31, and reflect non-image light away
from projection path 31. The deflection state or angle of each
mirror is individually controlled by changing memory contents of an
underlying addressing circuit and mirror reset signal. The array of
mirrors is arranged such that each mirror is responsible for light
output of a single pixel in the video image. Control signals
corresponding to pixel output are supplied to control electrodes
disposed in the vicinity of each mirror, thereby selectively
deflecting individual mirrors by electromagnetic force according to
video data on a pixel by pixel basis. Light reflected by each
mirror is then transmitted along projection path 31, through prism
structure 110, and out of projection chamber 14 using projection
lens system 112.
[0087] A controller 114 is included with optical modulation device
102 and provides control electrical signals that direct each
micromechanical mirror to desired light reflecting states
corresponding to pixel video data for each pixel. Control and power
cabling 120 provides electrical communication between controller
114 and control circuitry 76 in base 12 (FIG. 3). Thus, at least
one electrical connector included in cabling 120 couples to
controller 114 in projection chamber 14 and to control circuitry 76
in base 12 and provides electrical communication therebetween. A
power line within cabling 120 extends between optical modulation
device 102 in projection chamber 14 and power supply 66 in base 12
and provides power from power supply 66 to device 102. Control and
power cabling 120 then travels through positional interface 16,
which includes one or more holes or apertures that allow control
and power cabling 120 to pass therethrough without impingement on
control and power cabling 120 for any position of projection
chamber 14. In embodiments, control and power cabling 120 passes
through a plastic tube in positional interface 16 to further
protect the wires.
[0088] The illumination angles for optical modulation device 102
are set by the output direction of fiber-optic interface 102,
arrangement of relay optics 106 and 108, and the faces of prism
structure 110. After light reflection by individual mirrors of
optical modulation device 102, reflected light exits prism
structure 110 towards lenses 112 along projection path 31.
[0089] Vents 118 are disposed on an aft portion of projection
chamber housing proximate to optical modulation device 102. An air
duct 122 includes a high-pressure end proximate to optical
modulation device 102 and controller 114, and a low pressure end
disposed within base 12. As mentioned above, fans 62a and 62b may
draw air from within base 12 and exhaust the air out exhaust vents
24b, which creates a negative pressure within base 12 relative to
the ambient room or surroundings. Correspondingly, fans 62a and 62b
create a negative pressure for the end of air duct 122 within base
12 relative to the opposite end in projection chamber 14, which
would otherwise rest at room pressure due to vents 118. By
disposing one end of air duct 122 within base 12 and the other end
in a space 125 around optical modulation device 102, fans 62 thus
draw air from the space 125 and cool optical modulation device 102.
Cumulatively, cooling air is drawn from the ambient surroundings
around projection chamber 14, through vents 118 and into a space
125 surrounding optical modulation device 102, into duct 122 at end
122a, through duct 122, out duct 122 at end 122b, into base 12, and
out air vents 24b. Fans 62 maintain end 122b at a low pressure
relative to end 122a, and thus providing cooling for optical
modulation device 102.
[0090] A projection lens system 112 is disposed along projection
path 31 for outputting light transmitted by the optical modulation
device along projection path 31. Projection lens system 112
manipulates image light transmitted by optical modulation device
102 along projection path 31 such that a projected image cast on a
receiving surface enlarges as distance from output optical
projection lens 37 to the receiving surface increases. Projection
lens system 112 comprises lenses 112a, 112b, 112c and output
optical projection lens 37, each of which are disposed centrically
along and orthogonal to projection path 31. Distances between each
lens may vary with a desired splay angle from output optical
projection lens 37, as may the number of lenses used. In
embodiments, display device 10 is designed for a short throw
distance, such as between about six inches and about fifteen feet.
Display device 10 may also include one or more buttons or tools
that allow a user to manually focus and manually zoom output from
projection lens system 112. Projection chamber 14 may also include
a lens between optical modulation device 102 and prism 110 that
converges image light reflected by device 102 towards projection
path 31. This allows a reduction in output lens 112 diameters, and
a corresponding reduction in diameter and size for projection
chamber 14.
[0091] In some other embodiments, other types of light modulators
and light path designs may be employed. For example, fiber-optic
cabling 72 may be arranged for a multiple light path design to
transmit light to three primary color dedicated LCD optical
modulators, or to three primary color dedicated DMD optical
modulators. In the case of an LCD optical modulation device,
selective transmission of light comprises selective passage of
light through a liquid crystal medium on a pixel by pixel
basis.
[0092] In addition, although base 12 of FIG. 3 has been primarily
described with respect to components dedicated to projection
functionality, it is understood that base 12 may be inclusive in a
larger system, or comprise components not directed solely to
display device 10 output. For example, base 12 may be part of a
computer housing that includes components for projection
functionality and components for computer functionality in a
computer system, such as a desktop computer or video game console.
Computer functionality components may include a processor, a hard
drive, one more interface and control boards, a disk or floppy
drive, etc. In this case, housing 20 is considerably larger to
accommodate the combined functionality and components. In addition,
some components may be shared, such as a power supply and fans used
for movement of air within the housing.
[0093] FIG. 10 shows a front view illustration of display device
1020 with three positional interfaces 1016 for multiple light
outputs from projection outputs 1014 in accordance with a
non-limiting embodiment. The positional interfaces 1016 comprise
fiber-optic interfaces 1004, relay optics 1006 and 1008, prism
structures 1010. Fiber-optic cablings 1072 attaches to fiber-optic
interfaces 1004 and output light to relay optics 1006. Together,
fiber-optic cablings 1072 and fiber-optic interfaces 1004 direct
light generated by the respective light sources to prisms 1010. In
embodiments, fiber-optic cablings 72 and interfaces 1004 are
configured with respect to prism 1010 so as to provide an optical
path of incident light that is about perpendicular to an incident
surface of prism 1010.
[0094] Fiber-optic interfaces 1004 allow a designer to arrange
fiber-optic cablings 1072 and fiber-optic interfaces 1004 such that
the fiber-optic interfaces 104 direct light at a particular desired
angle relative to prism 1010. Relay optics 1006 and 1008 convert
light receive from fiber-optic cablings 72 to light suitable for
transmission into prism structures 1010. This may include shaping
and resizing light flux received from fiber-optic cablings 72 using
one or more lenses. In other embodiments, display device 1020
comprises a pair of fly-eye lenses arranged in the optical path
between the light sources and prisms 1010.
[0095] Prism structures 1010 are optical modulation systems that
provide light to optical modulation devices at predetermined
angles. The illumination angles for the optical modulation devices
are set by the output directions of the fiber-optic interfaces,
arrangement of relay optics 1006 and 1008, and the faces of prism
structures 1010. After light reflection by individual mirrors of
the optical modulation devices, reflected light exits prism
structures 1010 along projection paths 1031a, 1031b and 1031c,
respectively, from the different positional interfaces 1016. In
some other embodiments, other types of light modulators and light
path designs may be employed. In the present embodiment,
fiber-optic cablings 72 are arranged for a multiple light path
design to transmit light from each of the outputs 1014.
[0096] FIG. 11 illustrates a perspective view of a display device
10a in accordance with one of the present embodiments. As shown,
display device 10a comprises a base 12, two projection chambers 14,
and two positional interfaces 16.
[0097] FIG. 12 illustrates a schematic chart illustrating optical
path from a light source 64 configured in base 12 (FIG. 11) to each
projection chamber 14. Light source 64 includes a plurality of
laser sets, such as a red laser set 961, a green laser set 962 and
a blue laser set 963, generating a plurality of laser beams with
different color to one another, such as red laser beam, green laser
beam and blue laser beam. As shown, light source 64 also includes a
switch 8 which receives the red laser beam, green laser beam and
blue laser beam from the red laser set 961, the green laser set 962
and the blue laser set 963 respectively.
[0098] In embodiments according to FIGS. 11 and 12, display device
10a comprises two projection chambers 14. Each of the projection
chambers 14 includes an optical modulation device 102 and a
projection lens system 112. The optical modulation device 102 is
configured to selectively transmit light generated by the light
source according to a receiving video data. The projection lens
system 112 is configured to output light transmitted by the optical
modulation device 102 along a predetermined projection path, so as
to display projection images on one or more external receiving
surfaces.
[0099] The switch 8 is capable of diverting the red laser beam, the
green laser beam and the blue laser beam in a predetermined
sequential order to each of the two optical modulation devices 102.
For instance, in embodiments, there are three modes corresponding
to a first time frame, a second time frame and a third time frame,
respectively.
[0100] In the first mode, during the first time frame, red laser
beam is transmitted from switch 8 to optical modulation device
102a; green laser beam is transmitted from switch 8 to optical
modulation device 102b; and blue laser set 963 is turned off or
stays in a low voltage stage which no laser light is generated.
[0101] In the second mode, during the second time frame, green
laser beam is transmitted from switch 8 to optical modulation
device 102a; blue laser beam is transmitted from switch 8 to
optical modulation device 102b; and red laser set 961 is turned off
or stays in a low voltage stage which no laser light is
generated.
[0102] In the third mode, during a third time frame, red laser beam
is transmitted from switch 8 to optical modulation device 102b;
blue laser beam is transmitted from switch 8 to optical modulation
device 102a; and green laser set 962 is turned off or stays in a
low voltage stage which no laser light is generated.
[0103] Lasting time of the first time frame, the second time frame
and the third time frame may be identical to one another in
embodiments. Namely, the first mode, the second mode and the third
mode take turns evenly to be applied in the light source 64. In
some other embodiments, lasting time of the first time frame, the
second time frame and the third time frame may differ from one
another according to system requirement. Such adjustment toward
lasting time may be used as color control manner of the display
device 10a.
[0104] FIG. 13 illustrates that display device 10a may project
projection images on a receiving surface 521. Display device 10a
according to 10 comprises two projection outputs with moveable
projection chambers and output optics which controllably position
project images in a first projection area 501 and a second
projection area 502 respectively. In embodiments, projection area
501 and projection area 502 are set adjacent to each other
horizontally but not connected.
[0105] It is to be understood that that keystone correction may be
applied in the condition of the projection path 31 of a projection
chamber 14 being not perpendicular to receiving surface 521, so as
to display images corresponding to orthogonal image
coordinates.
[0106] The orthogonal image coordinates refer to a stored data
format, positional arrangement for pixels, or an assumed output
format for display of the video information. In some embodiments,
pixel values are assigned or stored according to a positional
arrangement of pixels in a planar image, such as a right angle x-y
coordinate system. The x-y coordinate pixel locations are then used
to determine where video data is output on an image. Characterizing
video information according to orthogonal image coordinates denotes
how they are stored and/or intended for display, and not
necessarily how they are actually cast or displayed. Thus, for
several present embodiments, the projection image may not always be
truly orthogonal if keystone correction has not been applied.
Namely, when the projection path 31 of a projection chamber 14 is
not perpendicular to receiving surface 521, keystone distortion of
the image may appear. Keystone distortion often produces a
trapezoidal image for rectangular video information intended for
display according to orthogonal image coordinates. In some
embodiments, the display device includes keystone correction tool
for reducing keystone distortion.
[0107] In embodiments, display device 10a also includes one or more
image detectors, such as camera module, configured to detect image
of external environment, such as receiving surface 521, and to
detect projection images, such as video images projected in first
projection area 501 and second projection area 502. In embodiments,
two image detectors are disposed within each of the two projection
chamber 14 of display devices 10a respectively, so as to utilize
optical function of the projection lens system 112. In some other
embodiments, image detector is disposed outside projection chamber
14; and each of projection chambers 14 comprises an image detector
coupled to projection chamber housing externally. In other
embodiments, display device 10a may comprise one or more image
detector coupled to base 12, optionally with a positional interface
to shift viewing angle of image device so as to detect image at
various positions.
[0108] In other embodiments, image detector(s) may provide
information of projection image to display device 10a for automatic
keystone correction. Display device 10a may firstly project test
images in the first projection area 501 and the second projection
area 502. The test images may be quickly flashed in some cases so a
user may or may not be aware of their presence. Each of the image
detectors is capable of detecting the projection test image in
real-time and providing the receiving information to control
circuitry 76 so as to fix the keystone distortion in closed loops.
In embodiments, the detected outlines of the projection images 501
and 502 are compared to predetermined orthogonal image coordinates
so as to perform automatic keystone correction function. In other
embodiments, the default test image may include a horizontal
reference line 531 and a vertical reference line 532. The
horizontal reference line 531 and the vertical reference line 532
may include graduation label therein. The automatic keystone
correction may be performed by detecting distortion of the
horizontal reference line 531 and the vertical reference line 532
of the projection image.
[0109] In embodiments, the display device 10a may include an image
coordination tool to automatically coordinate multiple projection
areas, such as first projection area 501 and second projection area
502.
[0110] As shown in FIG. 13, display device 10a may be used as video
output of a computer device with a dual-screen GUI (graphic-based
user interface). For instance, first projection area 501 is used
for displaying host or original desktop; and second projection area
502 is used for displaying extension desktop.
[0111] A user may wish to have the first projection area 501 and
second projection area 502 with the same size and the same
altitude. In this application, the horizontal lines 531 detected by
the image detector may be used by the image coordination tool for
measuring the size and relative location of each projection area.
By aligning the horizontal lines, the image coordination tool is
capable of arranging the first projection area 501 and second
projection area 502 at a same altitude.
[0112] In another embodiment, images 501 and 502 are connected
horizontally. In this case, the image coordination may be used to
remove any projection overlap between the images 502 and 504 on the
receiving surface--after keystone correction. The removed portion
of display may be taken from either projected image 502 or 504. A
graphics processor associated with the images may then provide a
continuous digital workspace between projection images 501 and 502,
e.g., a mouse or pointer moves smoothly between the projection
images 501 and 502 at their intersection.
[0113] FIG. 14 illustrates that display device 10 may project two
projection images on a receiving surface 521 in accordance with one
of the present embodiments. Display device 10 according to FIG. 3
comprises three projection chambers 14. Two video signal sources
are coupled to display device 10 so only two projection chambers 14
are used in this instance. Projection images are displayed in first
projection area 501 and second projection area 502 respectively
after keystone correction. In embodiments, projection area 501 and
projection area 502 are set vertically adjacent to each other but
not connected. Alternatively, the projection areas 501 and 502 may
overlap or rest directly adjacent to each other in a vertical
direction. The vertical reference lines 532 of each area captured
by image detector are used by the image coordination tool to line
up the first projection area 501 and the second projection area 502
by aligning the vertical reference lines 532.
[0114] FIG. 15 shows that display device 10 may project a
projection image on a receiving surface 521 in accordance with one
of the present embodiments. Display device 10 according to FIG. 3
comprises three projection chambers 14. In embodiments, a single
video signal source is coupled to display device 10; and three
projection chambers 14 are used to output image jointly in first
projection area 501, second projection area 502 and a third
projection area 503. In another words, each of the first projection
area 501, the second projection area 502 and the third projection
area 503 is for displaying portion, such as one third, of a
projection image. In embodiments, horizontal reference lines 531
with graduation labels may be employed by keystone correction tool
and image coordination tool to adjust the projection output
matching such predetermined settings and/or digital placement of
each image relative to each other. In embodiments when the
projection device 10 includes a positioning interface as described
above, this digital positioning control of each image provides two
mechanisms for positioning a projection image.
[0115] FIG. 16 illustrates that display device 10 may project three
projection images on a receiving surface 521 in accordance with one
of the present embodiments. Display device 10 according to FIG. 1,
3 or 4 comprises three projection outputs.
[0116] In embodiments, the display device 10 uses three projection
chambers 14 to project images within three projection areas. First
projection area 501 and third projection area 503 are lined up
horizontally while second projection area 502 is placed below the
first projection area 501 and third projection area 503 as shown.
In embodiments, horizontal reference lines 531 and vertical
reference lines 532 with graduation labels may be employed by
keystone correction tool so as to form projection areas with the
same size and with reduced keystone distortion. Intersections of
horizontal reference lines 531 and vertical reference line 532 may
be used by image coordination tool to adjust locations of the three
projection areas to match such setting or default.
[0117] In embodiments which user may selectively move and locate
first projection area 501, the second projection area 502 and third
projection area 503 on the receiving surface 521 according to
his/her preference. User may control the position of each
projection areas by using OSD (On-screen display) interface 533
such as an arrow as shown. In other embodiments, display device 10
incorporates a built-in screen or is able to connect to an
accessory external display 19 as shown. User may drag each of the
projection areas to a preferred location through GUI
(Graphics-based user interface) displaying on built in screen or
accessory external display 19 by pointer, such as mouse input. In
other embodiments user may drag each of the projection areas by
finger touch on the built-in screen or accessory external display
19 which has touch-screen function.
[0118] FIG. 17 shows other embodiments which display device 10
projects three projection images on three receiving surfaces, first
receiving surface 601, second receiving surface 602 and third
receiving surface 603 on three walls respectively. Display device
10 according to FIG. 3 comprises three projection chambers 14. Each
of the projection chambers projects image on one receiving
surface.
[0119] As shown in FIG. 17, projection images on second receiving
surface 602 and third receiving surface 603 may need keystone
correction due to projection paths 31 from display device 10 being
not perpendicular to second receiving surface 602 and third
receiving surface 603. Projection image on first receiving surface
601 may also need keystone correction. Although in FIG. 17 the
projection path from display device 10 is perpendicular to first
receiving surface 601, it may not be perpendicular in another
cross-section or horizontally centered to Wall 1 as shown, such as
in the condition that display device 10 disposed on floor; and the
image on surface 601 may need situation specific keystone
correction.
[0120] In embodiments, the display device 10 is employed by a video
game device for generating near-peripheral surrounding video. For
example, a user sitting in front of display device 10 benefits from
a full peripheral vision video game experience where objects may
appear from not only the front but also the sides and be detected
by peripheral vision. In embodiments, the display device 10 may be
installed near to ceiling to prevent casting a shadow of user.
[0121] It should be noted that the above-described embodiments are
more general than connecting multiple images and are applicable to
a variety of techniques for casting the images on a surface
efficiently where the assumption of the "fixed TV box" is not
available. In other words, more generally, the presently described
embodiments enable the projected content to be displayed according
to a layout to optimize viewability.
[0122] In this regard, without knowing where a user is looking at
with his or her eyes, for multiple images, embodiments have been
described herein that ensure vertical lines are vertical and
horizontal lines are horizontal. In yet another embodiment, with a
camera configured to receive video input resulting from the
projection of multiple images on the wall, in effect, the device
can "see what it is doing" with respect to the projected content
and make intelligent adjustments where something about the
projected content is disturbing viewability.
[0123] A one image projector usually casts orthogonal to its
receiving surface. The three image projection system having
multiple outputs as described in various embodiments herein will
generally have vertical and horizontal keystoning effects, however,
since typically orthogonality will not necessarily be maintainable
or sustainable. Accordingly, various embodiments can employ
software that coordinates the projection of images dynamically
based on feedback from the camera about how the images are
displaying.
[0124] In some cases, a camera included in the projection system
obtains image feedback for each of the three images. A controller
on the projector or a device in communication with the projector
receives the camera feedback and changes vertical and horizontal
keystoning accordingly. The camera can also provide a measure of
vertical and horizontal distortion for each image.
[0125] For example, a continuous horizontal line on all three
images may be aligned, despite the offset image castings in height
on the three surfaces--both in the horizontal and vertical
directions. In this regard, video games often require knowledge of
horizon lines for presentation of game graphics. The presently
described embodiment thus facilitates the consistent presentation
of video games despite different image casting conditions (e.g., as
might be ubiquitous from a handheld device that moves with a user's
hands).
[0126] Software alignment and coordination of the images is thus
achievable. The result is the automatic maintenance of rectangular
images on all three surfaces. Coordination marks may be cast to
facilitate image vertical and horizontal alignment. These are lines
or other fiduciary graphics that permit closed loop feedback with
the camera. For example, red lines that should be connected on
adjacent images may be flashed. The software may then manipulate
the images to suitably align the fiduciary lines.
[0127] FIG. 18 shows other embodiments which display device 10
projects three projection images on first receiving surface 601,
second receiving surface 602 and third receiving surface 603. First
receiving surface 601 is on a wall in front of the display device
10. Second receiving surface 602 is on ceiling; and third receiving
surface 603 is on floor.
[0128] In embodiments which the display device 10 employed by video
game device for generating near-peripheral surrounding video, user
may experience. For example, these kinds of embodiments may be
applied in helicopter, plane and other flying games to form full
visual feedback for a horizon change, e.g., the video ground rises
or falls. Image coordination tool may be applied to adjust
projection images to be projected at proper positions. Other
embodiments of the three receiving surfaces may include projecting
image on two walls and a ceiling, or on two walls and a floor. It
is to be understood and appreciated that other multi-surface
examples exist which are to be included within the scope of this
disclosure and claims appended hereto.
[0129] FIG. 19 shows an example block diagram illustrating a
control circuitry 76 of display device 10 in accordance with
several embodiments. As mentioned, input/output circuitry 74 and
input ports 78 collectively permit communication between display
device 10 and a device that outputs a video signal carrying video
data. Video signal provided to control circuitry 76 may be in an
analog or digital form. In some embodiments, input/output circuitry
74 and control circuitry 76 convert analog video signals into
digital video signals suitable for digital operation of optical
modulation device 102. In some other embodiments, input/output
circuitry 74 may also include support software and logic for
particular connector types, such as processing logic required for
video signal input from S-video cabling or digital video
signal.
[0130] Control circuitry 76 receives video signal that has been
pre-processed by input/output circuitry 76 and then further
processes video signal so as to provide control signals to
components of display device 10 for outputting video projection
according to video signal.
[0131] In embodiments, control circuitry 76 may include a processor
761, a memory 762, a control input/output interface 763, a video
input interface 764 and a video output interface 765. Video input
interface 764 couples to input/output circuitry 74 for receiving
pre-processed video signal from input/output circuitry 764. Video
output interface 765 couples to light source 64 and optical
modulation devices 102 for providing control signals, which are
based on the video signal and further modulation by control
circuitry 76.
[0132] Control input/output interface 763 may include user
interface 731, image detector interface 732, network interface 733
for coupling to user input devices, image detector and a network
connecting to display device 10. User input device may include
embedded/built-in control button(s), keypad, display, touch screen
or stick controller; or accessory external mouse, keyboard, display
with or without touch-screen function, remote controller or other
controller. OSD (On-screen display) control instructions may be
displayed on embedded/built-in display or touch screen, external
display, or on the projection image.
[0133] Processor 761 may be a commercially available processor,
controller or microprocessor such as one of the Intel or Motorola
family of chips for processing/calculating data based on programs,
modules or data structures in memory 762. In other embodiments,
processor 761 and at least part of memory 762 are manufactured as a
single chip; namely, a system on chip application. Memory 762 may
include high speed random access memory and may also include
non-volatile memory, such as one or more magnetic disk storage
devices. Memory 762 may optionally include one or more storage
devices.
[0134] The memory 762 in control circuitry 76 may store the
following programs, modules and data structures, or a subset or
superset thereof: an operation system 710, a video signal
processing module 711, a light source control module 712, an
optical modulation control module 713, a key stone correction tool
714, an image coordination tool 715, a thermal control application
718, an OSD (On-screen display) application 719, etc.
[0135] Operating system 710 includes procedures for handling
various basic system services and for performing hardware dependent
tasks.
[0136] OSD (On-screen display) application 719 contains control
icons or figures that may be displayed on embedded/built-in display
or touch screen, external display, or on the projection image; it
also contains rules and instructions in associated with user's
input.
[0137] Video signal processing module 711 is used for processing
the video signal from input/output circuitry 764 so as to construct
frame based control signals which may be adopted by optical
modulation device 102.
[0138] Light source control module 712 is for controlling red laser
set 961, green laser set 962, blue laser set 963 and switch 8
within light source 64 in order to drive light source 64 to divert
the red laser beam, the green laser beam and the blue laser beam in
a predetermined sequential order to each of the three projection
chambers 14. Optical modulation control module 713 is for driving
optical modulation device 102.
[0139] Keystone correction tool 714 may include one or more
distortion reducing algorithm. It may utilize several stored
default test images 741 such as those include horizontal references
line 531 and/or vertical reference lines shown in the figures
described above, and also utilize detected information 742 such as
projection image feedback detected by image detector to perform
auto keystone correction. In embodiments, keystone correction tool
714 includes a distortion look-up table to fast define a
predetermined correction parameter according a match-up result of
detected projection image feedback and default test image.
[0140] Image coordination Tool 715 may include one or more
algorithm to coordinate images to be projected by multiple
projection chambers according to user's preference or default
configurations. In embodiments, default image configurations 751
and/or user preferences 752 may be stored in the memory 762. Image
coordination tool 715 may employ keystone correction tool 714 for
coordinating multiple images in a close loop, so as to generate
video output not only at target locations but also better matching
desired shapes and sizes. In embodiments, an alignment application
753 included in image coordination tool 715 may be used for
aligning multiple images such as shown in FIGS. 13, 14, 15 and 16;
alignment application 753 may employ horizontal reference line 531
and/or vertical reference line 532 of keystone correction tool 714
to perform its function.
[0141] Thermal control application 718 may include stored thermal
regulation 781 and fan driver 782. Temperature information detected
by thermal detector 80 is provided to control circuitry 76 through
thermal interface 738. Thermal control application 718 drives 62a
and/or 62b based on thermal regulation 782 and the received thermal
information.
[0142] FIG. 20 shows an exemplary video output according to
embodiments. In embodiments, for example, display device 10
allocates relatively higher processing resource for the central
image 2004 and allocates relative lower processing resource for the
subsidiary images such as the right image 2002 and the left image
2006; namely, the video resolution of central image 2004 is higher
than the video resolution of right image 2002 and left image 2006.
This may be performed by a resolution adjustment instruction 754
included in the image coordination tool 715 and may benefit data
processing for operating system 710. In this example, the display
device can be a portable electronic device, such as a mobile phone
or other handheld media or content rendering device, and with the
control of multiple light outputs implemented by the portable
electronic device as described herein for one or more embodiments,
significant coverage of the wall can be achieved, though perhaps
not full coverage due to limitations on power of portable
electronic devices, and the like.
[0143] Of particular note are the limitations that gaming content
on handheld devices has suffered in the past without the projection
of content as described herein. Namely, due to limited screen real
estate, the gaming experience on handheld devices has suffered. In
short, a limited amount of eye or pixel resolution makes some tasks
in a game tedious if only a small screen is available. For
instance, slight motion may be hardly noticeable on a small screen
or a screen having limited resolution. However, with the multiple
projection output switching techniques described herein, a much
larger screen is realized on a wall or other surface, and the
gaming experience is vastly improved from small form factor
devices, e.g., gaming from small form factors is limitless when
greater than equal to 60 inch images can be projected efficiently
onto a surface. Additionally, while documents such as Excel
spreadsheets are difficult to view on a small screen, when
projected according to one or more of the embodiments herein, the
Excel spreadsheet can be viewed at full or even greater size.
[0144] Besides the central-weighted embodiments as described, the
display device 10 may allocate relative higher processing resource
for a predetermined angular range of user's visual field. This may
be achieved by knowledge of the video data being presented and/or
utilizing an eye sensor which is coupled to control circuitry and
is configured to detect a direction of line of vision of a user. In
the former case, for example in a video game in which the game
knows and controls video output to the user, the system may make
assumptions about where the user is gazing to reduce video
information and processing to other parts. In the latter case, eye
detection module 755 included in the image coordination tool 715
uses the fovea information retrieved by the eye sensor to set up a
weighted video area; and the resolution adjustment instruction 754
may be applied to areas that outside the weighted video area so as
to perform resolution adjustment, such as reducing video resolution
in such area.
[0145] In embodiments, video details are reduced outside about
forty degrees in angular separation from user's fovea, i.e., the
line of vision. In other embodiments, video details are reduced in
stages. For example, color may be reduced after twenty degrees in
angular separation from user's fovea; and resolution may be
diminished after forty or sixty degrees, etc.
[0146] FIG. 21 shows another exemplary video output according to
embodiments in which a multimedia console, personal computing
device, set top box, disk player, media rendering device, etc.,
i.e., a system with greater projection capabilities than a typical
handheld device, is employed to project an image across an entire
wall floor to ceiling. As with FIG. 20, relatively higher
processing resources can be allocated for the central image 2104
and relatively lower processing resources can be allocated for the
subsidiary images, such as the right image 2102 and the left image
2106. In this example, in contrast to a portable handheld device
which may have some limitations, the display device can be any
computing device, such as a PC, set top box, multimedia or gaming
console, or other full size media rendering device, which can
display the projected images/video across the wall floor to ceiling
in accordance with the techniques herein.
[0147] FIG. 22 illustrates an exemplary, non-limiting embodiment
employing content sensitive determination of foreground and
background content of projected media, such as video game content,
enhances a user experience, and is explained following some
presentation of background regarding the human visual system. In
this regard, with knowledge of which part of media content a viewer
is staring or gazing at with his or her eyes, a publisher of the
media content, or media rendering device, can apply enhancement
algorithms to the media content, such as a video game, based on
distinguishing between foreground imagery and background imagery.
Accordingly, in various non-limiting embodiments, user context
sensitive techniques for distinguishing between foreground and
background for video output for multiple projected images are
provided.
[0148] By way of some background, human vision employs a number of
information reduction mechanisms to reduce the amount of visual
information in an environment to a manageable level. Such
mechanisms include shape detection and foreground/background
separation. Foreground/background separation divides an environment
to into a foreground where more information is processed (e.g. more
detail) and a background where less information is processed (e.g.
less detail). Shape detection allows a person to recognize objects
based on reduced information, such as outer contours that resemble
a shape for the object.
[0149] In one embodiment, the invention leverages the background
information reduction mechanism to reduce the amount of video
information displayed by a multiple image projector. The foreground
of human vision is defined by the angular separation of rods and
cones. Cones are concentrated in the center, or fovea centralis.
Rods are absent there, but dense elsewhere.
[0150] Measured density curves for the rods and cones on the retina
show an enormous density of cones in the fovea centralis, which are
attributed for color vision capability and the highest visual
acuity. Visual examination of small detail involves focusing light
from that detail onto the fovea centralis. On the other hand, the
rods are absent from the fovea. At a few degrees away from it their
density rises to a high value and spreads over a large area of the
retina. These rods are responsible for night vision, a highly
sensitive type of motion detection, as well as our peripheral
vision.
[0151] Notably, the cones are responsible for high resolution
vision. The eye moves continually to keep the light from the object
of interest falling on the fovea centralis where the bulk of the
cones reside.
[0152] Correspondingly, with knowledge of foreground and background
areas in media content, the amount of visual information in
background portions of the video display can be reduced. This
technique leverages the foreground/background visual processing
mechanism in humans to reduce video storage and processing demands.
Since an individual processes less information in a background
visual region, reducing video output in an inactive portion may not
sacrifice perceived video quality. In one non-limiting embodiment,
video detail is reduced outside about 40 degrees in angular
separation from the fovea. Other angular separation amounts or
ranges can be suitable for use based on one or more variables
affecting an environment.
[0153] In another specific embodiment, video detail is reduced in
stages. For example, color may be reduced after 20 degrees in
angular separation from the fovea, resolution may be diminished
after 40 or 60 degrees, etc. In one embodiment, a portion of video
of interest is used to determine where the person is looking, e.g.,
text that they should be reading at a known location. Video away
from this foreground section is then deteriorated in acuity and
detail.
[0154] There are at least two techniques for separating foreground
and background. First, a camera can be used to detect where the
person is looking to help determine where the person's visual
foreground is, i.e., gaze tracking can be employed. The camera can
be calibrated to find a user and the user's eyes at a time of
context sensitivity, e.g., when the user is entering input into a
field or other UI element on screen (for example, entering a user
name). In this regard, at the time of entering the input, it is
highly likely the user is staring at that field or other UI
element. At such time, not only can the UI element be treated like
the foreground, thereby reducing background requirements, but also
the system is calibrated to find the user's eyes. Information in
the background section may then be decreased in detail,
particularly in color, while maintaining luminance detail and
motion so as to not diminish from relatively larger perception of
these in the periphery.
[0155] However, with respect to a second technique, gaze tracking
may not be available or possible for certain environments for
projecting video content as described herein, e.g., for some
embodiments involving a handheld device. In such instances, the
notion of real-time determination of background and foreground can
be achieved based on context sensitive user actions. For instance,
as shown in FIG. 22, a user may be playing a video game in which a
first person shooter has gone back in time to hunt dinosaurs. In
such a game, when the user aims target 2202 on the head of 3-D
dinosaur object 2204, it is generally known that the user is
looking at the head of the dinosaur. In such case, entire dinosaur
2204 (or just its head) can be treated as the foreground (the
currently important visual data) and the rest of the imagery 2206
can be treated as background and thus de-emphasized. Thus, video
games are one application that can benefit from near-peripheral
surrounding video. Other examples can be given where it is known
based on display or game content what users are most likely to be
looking at based on context, e.g., anytime the content demands
entering input associated with a specific location on-screen.
[0156] The de-emphasis of background results in the reduction of
size of the video data displayed and also reduces the processing
load to output large images, saving power as well. Large images
cast by multiple image projectors, as described herein, is
revolutionary in that it provides vastly greater visual information
for a person than in the past, i.e., this represents a paradigm
shift from LCD screens. Portable display manufacturers, video game
companies, graphics companies, etc. can all take advantage of the
techniques for discriminating between foreground and background
content as described herein.
[0157] FIG. 23 illustrates another type of projector module that
can be employed in some embodiments. Projector module 98 includes
housing 90, red laser set 92, green laser set 94, blue laser set
96, optics 91, control circuitry 97, micro scanner 99, input/output
circuitry (not shown), input/output interfaces (not shown), power
supply (not shown) and projection lens system 93. Projector module
98 includes three light sources 92, 94 and 96, but with three
separate outputs 95. In this regard, any of the embodiments
described herein in the context of multiple chambers can be
provided more generally as multiple projection outputs without
constraining each light source to a chamber.
[0158] Housing 90 defines outer dimensions of projector module 98
and also provides mechanical protection for internal components of
projector module 98. Housing 90 may also include air vents that
permit airflow between chamber of housing 90 and external
environment. Vents may also be placed on the housing 90. Power
supply provides electrical power to red laser set 92, green laser
set 94, blue laser set 96 and other components within projector
module 98 that consume electrical power. Thus, power supply may
provide electrical energy to control circuitry, input/output
circuitry, fans, control circuitry 97 and micro scanner 99.
[0159] Several different embodiments of red laser set 92, green
laser set 94 and blue laser set 96 may be provided. The optics 91
receives red, green and blue laser light from red laser set 92,
green laser set 94 and blue laser set 96 respectively and provides
three separate light outputs to micro scanner 99. The input/output
circuitry provides video signal, from input/output interfaces, to
control circuit 97. The control circuit 97 controls red laser set
92, green laser set 94 and blue laser set 96 respectively. During a
time frame of pixel, red laser set 92, green laser set 94 and blue
laser set 96 respectively generates predetermined power of laser
corresponding to a predetermined gray scale of red, green or blue
based on control signals from control circuitry 97.
[0160] FIG. 24 illustrates another non-limiting embodiment based on
the type of projector module set forth in FIG. 24. Similar to FIG.
4, projection apparatus 2402 includes separate laser (or LED) light
sources 2492, 2494, 2496, which are input into switch 2408 which
performs digital switching among light sources 2492, 2494, 2496.
The outputs from switch 2408 from the controlled timing applied to
light sources 2492, 2494, 2496 are input to projector modules 2490
respectively generating projected outputs a, b and c. Each
projection module 2490 includes modulation optics 2491a, scanner 99
and projection lens systems 2493 for generating the respective
outputs a, b and c.
[0161] Although the foregoing invention has been described in some
detail for purposes of clarity of understanding, those skilled in
the art will recognize that various modifications may be made
within the scope of the appended claims. For example, although the
positional interfaces described herein have coupled to the
projection chamber from the bottom, it is understood that a
positional interface may couple to the projection chamber from the
rear. In this case, an air duct, electrical connection and optical
cabling may extend through the projection chamber to its respective
functional location. The invention is, therefore, not limited to
the specific features and embodiments described herein and claimed
in any of its forms or modifications within the scope of the
appended claims.
[0162] What has been described above includes examples of the
innovation. It is, of course, not possible to describe every
conceivable combination of components or methodologies for purposes
of describing the subject innovation, but one of ordinary skill in
the art may recognize that many further combinations and
permutations of the innovation are possible. Accordingly, the
innovation is intended to embrace all such alterations,
modifications and variations that fall within the spirit and scope
of the appended claims. Furthermore, to the extent that the term
"includes" is used in either the detailed description or the
claims, such term is intended to be inclusive in a manner similar
to the term "comprising" as "comprising" is interpreted when
employed as a transitional word in a claim.
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