U.S. patent application number 10/962878 was filed with the patent office on 2005-05-26 for multi-projection display.
This patent application is currently assigned to SEIKO EPSON CORPORATION. Invention is credited to Hasegawa, Hiroshi, Miyazawa, Yasunaga.
Application Number | 20050110959 10/962878 |
Document ID | / |
Family ID | 34431203 |
Filed Date | 2005-05-26 |
United States Patent
Application |
20050110959 |
Kind Code |
A1 |
Miyazawa, Yasunaga ; et
al. |
May 26, 2005 |
Multi-projection display
Abstract
A multi projection display includes a plurality of projector
units to modulate light from an LED light source according to image
information to project, a unit image information generating unit to
generate unit image information to be inputted to each of the
plurality of projector units, and a unit image information
correcting unit to correct the unit image information based on a
result of capturing projection images projected onto a transmissive
screen. For this reason, a shutter, which results in complicating
the construction, is not needed and further it is possible to
further reduce the adjustment time.
Inventors: |
Miyazawa, Yasunaga;
(Okaya-shi, JP) ; Hasegawa, Hiroshi; (Chino-shi,
JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 19928
ALEXANDRIA
VA
22320
US
|
Assignee: |
SEIKO EPSON CORPORATION
Tokyo
JP
|
Family ID: |
34431203 |
Appl. No.: |
10/962878 |
Filed: |
October 13, 2004 |
Current U.S.
Class: |
353/94 |
Current CPC
Class: |
H04N 9/3147 20130101;
G03B 21/28 20130101; H04N 9/3194 20130101; H04N 9/3185 20130101;
G03B 21/2033 20130101; G03B 21/10 20130101; G03B 37/04
20130101 |
Class at
Publication: |
353/094 |
International
Class: |
G03B 021/16 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 15, 2003 |
JP |
2003-355250 |
Claims
What is claimed is:
1. A multi-projection display, comprising: a plurality of projector
units to modulate light from a solid-state light source based on
image information; a unit image information generating unit to
generate unit image information to be input to each of the
plurality of projector units; and a unit image information
correcting unit to correct the unit image information based on a
result concerning capturing projection images projected onto a
screen.
2. The multi-projection display according to claim 1, the
solid-state light source being an LED light source, a semiconductor
laser light source, a solid-state laser light source, or an EL
light source.
3. The multi-projection display according to claim 1, the unit
image information correcting unit correcting the unit image
information based on the result of capturing adjusting unit images
projected by the projector units.
4. The multi-projection display according to claim 1, the unit
image information correcting unit correcting shapes, positions
and/or inclinations of the unit images to be projected by the
projector units.
5. The multi-projection display according to claim 1, the unit
image information correcting unit correcting brightness and/or
colors of the unit images to be projected by the projector
units.
6. The multi-projection display according to claim 1, the unit
image information correcting unit having a function of correcting
brightness and/or color for every pixel in the plurality of
projector units.
7. The multi-projection display according to claim 1, further
comprising: an image-capturing device to capture the projection
images projected onto the screen.
8. The multi-projection display according to claim 1, the unit
image information correcting unit correcting the unit image
information using correction parameters that are determined based
on the capturing result.
9. The multi-projection display according to claim 8, further
comprising: a correction parameter storing unit to store the
correction parameters.
10. The multi-projection display according to claim 8, further
comprising: a correction parameter automatic acquiring device to
capture an adjusting image in certain circumstances to
automatically acquire the correction parameters.
11. The multi-projection display according to claim 1, further
comprising: an optical correcting device to correct the position
and/or orientation of an optical element provided in the
multi-projection display.
12. The multi-projection display according to claim 11, further
comprising: an optical element automatic correcting device to
capture an adjusting image in certain circumstances to
automatically correct a position and/or orientation of the optical
element.
13. The multi-projection display according to claim 1, further
comprising: a solid-state light source control unit to control an
amount of light emitted from the solid-state light source
separately for every projector unit.
14. The multi-projection display according to claim 1, the
multi-projection display being a rear surface projection type
multi-projection display which further comprises a transmissive
screen to project the projection images from the plurality of
projector units.
15. The multi-projection display according to claim 1, the
multi-projection display being a front surface projection type
multi-projection display which projects the projection images from
the projector units onto a front surface thereof.
16. A multi-projection display, comprising: a plurality of
projector units, each having a solid-state light source to generate
a plurality of color light components; a plurality of
electro-optical modulating devices to modulate the plurality of
color light components respectively; and a projection optical
system to project color light components modulated by the plurality
of electro-optical modulating devices; a unit image information
generating unit to generate unit image information to be input to
the plurality of projector units respectively; and a solid-state
light source control unit to control an amount of light emitted
from the solid-state light source for every projector unit.
17. The multi-projection display according to claim 16, the
solid-state light source control unit having a function of
controlling the amount of light emitted from the solid-state light
source for every electro-optical modulating device.
18. The multi-projection display according to claim 16, the
solid-state light source control unit having a function of
dynamically controlling the amount of light emitted from the
solid-state light source.
19. The multi-projection display according to claim 16, the
solid-state light source control unit having a function of
controlling a voltage to be supplied to the solid-state light
source for every projector unit or for every electro-optical
modulating device.
20. The multi-projection display according to claim 16, the
solid-state light source control unit having a function of
controlling an emitting period of the solid-state light source for
every projector unit or for every electro-optical modulating
device.
21. The multi-projection display according to claim 20, the
electro-optical modulating device being a liquid crystal device
which writes one unit screen information twice or more, and the
solid-state light source control unit having a function of allowing
the solid-state light source to emit during one frame outside at
least the first writing period of the liquid crystal device.
22. The multi-projection display according to claim 20, the
electro-optical modulating device being a liquid crystal device
which writes an image sequentially for every screen region, and the
solid-state light source control unit having a function of allowing
the solid-state light source to emit during one frame outside the
image writing period of the liquid crystal device.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] Exemplary aspects of the present invention relate to a
multi-projection display.
[0003] 2. Description of Related Art
[0004] A related art multi-projection display includes a plurality
of projector units (projection optical unit) that are arranged in a
horizontal direction and in a vertical direction, and projection
images from the plurality of projector units are projected onto a
screen in a magnified scale to display one large screen image. For
example, see Japanese Unexamined Patent Application Publication No.
8-82854, Japanese Unexamined Patent Application Publication No.
8-94974, Japanese Unexamined Patent Application Publication No.
2001-339672, International Publication Pamphlet No. 99/31877,
Japanese Unexamined Patent Application Publication No. 9-326981,
Japanese Unexamined Patent Application Publication No. 2001-251651,
Japanese Unexamined Patent Application Publication No. 6-178327,
Japanese Unexamined Patent Application Publication No. 9-211386,
and U.S. Pat. No. 5,956,000. Such a multi-projection display can
display a high definition and high brightness image, as compared to
other related art projectors. Thus, it is expected that the
multi-projection display will be widely used in future in a
business field, such as a cinema, an art gallery, a museum, a
seminar hall, an assembly hall, a mini-theater, a public institute,
and a company or in a domestic field, such as an amusement and a
home theater.
SUMMARY OF THE INVENTION
[0005] In these related art multi-projection displays, if the
projection images from the respective projector units are not
smoothly connected to each other, it is impossible to match the
projection images from the respective projector units. Further, a
boundary is noticeable, and image quality is lowered.
[0006] For this reason, in the related art multi-projection display
disclosed in Japanese Unexamined Patent Application Publication No.
8-82854 and Japanese Unexamined Patent Application Publication No.
8-94974, in order to address the above problem, the projection
images from the respective projector units are made not to overlap
each other and the joint portions thereof become small.
[0007] However, in such related art multi-projection displays,
there is a problem in that at the time of setting up, it is not
easy to remove joint portions of the projection images from the
respective projector units or connect the projection images without
inconsistency.
[0008] For this reason, in the related art multi-projection display
disclosed in Japanese Unexamined Patent Application Publication No.
2001-339672, International Publication Pamphlet No. 99/31877,
Japanese Unexamined Patent Application Publication No. 9-326981,
Japanese Unexamined Patent Application Publication No. 2001-251651,
Japanese Unexamined Patent Application Publication No. 6-178327,
Japanese Unexamined Patent Application Publication No. 9-211386,
and U.S. Pat. No. 5,956,000 in order to address the above problem,
the projection images from adjacent projector units are made to
overlap partially on the screen such that the projection images are
smoothly connected to each other in the overlapped region.
[0009] However, in such related art multi-projection displays, if
the method of displaying the projection images from the respective
projector units on the screen are not accurately known, it is
impossible to smoothly connect the projection images on the screen.
Thus, when the related art multi-projection display disclosed in
Japanese Unexamined Patent Application Publication No. 2001-339672,
International Publication Pamphlet No. 99/31877, Japanese
Unexamined Patent Application Publication No. 9-326981, and
Japanese Unexamined Patent Application Publication No. 2001-251651,
is used with a watch camera or a digital camera, the projection
images (Adjusting images) from the respective projector units which
are displayed on the screen are captured and can be accurately
measured.
[0010] In the related art multi-projection display using these
image-capturing devices, in order to perform the adjustment to
match the projection images from the respective projector units,
there is a need to prevent influence of the projection image by an
adjacent projector unit. For this reason, the capturing operation
to the adjusting image needs to be performed for every projector
unit.
[0011] However, since a light emitting tube having high brightness
and high color-rendering property, such as a high pressure mercury
lamp or a metal halide lamp, is typically used as a light source of
the projector unit, after the light emitting tube is turned on,
obtaining a stable emitting state takes a minimum of several
minutes.
[0012] For this reason, in the related art multi-projection display
disclosed in Japanese Unexamined Patent Application Publication No.
2001-339672, shutters are arranged in front of the projection
lenses of the respective projector units and these shutters are
allowed to suitably operate. Thus, in the multi-projection display,
the capturing operation for every projector unit is performed in a
state in which the light emitting tube is turned on, such that the
adjustment operation is performed in a few minutes.
[0013] However, in the related art multi-projection display
disclosed in Japanese Unexamined Patent Application Publication No.
2001-339672, in order to perform the adjustment to match the
projection images from the respective projector units to each
other, the shutter must be operated mechanically for every
projector unit. Thus, there are problems in that the system becomes
complicated and the adjustment time is not easily reduced.
[0014] Accordingly, exemplary aspects of the present invention are
made to address and/or solve the above and/or other problems.
Exemplary aspects of the present invention provide a
multi-projection display which can further shorten the adjustment
time with no shutter required to match projection images from the
respective projector units.
[0015] The present inventors have studied to attain the above and
discovered that the above can be attained by using a solid-state
light source as a light source of the multi-projection display and
by performing an adjustment operation using light from the
solid-state light source, thereby completing the present
invention.
[0016] (1) A multi-projection display of an exemplary aspect of the
present invention includes a plurality of projector units to
modulate light from a solid-state light source based on image
information, a unit image information generating unit to generate
image information (Hereinafter, "unit image information") to be
input to each of the plurality of projector units, and a unit image
information correcting unit to correct the unit image information
based on a result of capturing projection images projected onto a
screen.
[0017] For this reason, according to the multi-projection display
of an exemplary aspect of the present invention, instead of a high
pressure mercury lamp or a metal halide lamp which has high
brightness, but takes several minutes until its emitting state is
stable after being turned on, a solid-state light source that
acquires a stable emitting state immediately after turning on is
used. Thus, it is possible to drastically shorten the time required
to capture the projection images to be projected from the
respective projector units onto the screen. As a result, it is
possible to drastically shorten the adjustment time to match the
projection images from the respective projector units. Thus
convenience is largely enhanced.
[0018] Further, according to the multi-projection display of an
exemplary aspect of the present invention, the solid-state light
source can be freely set to a turned-on state or a turned-off
state. Thus it is possible to remove the shutter which complicates
the system. Since the solid-state light source is in the stable
emitting state immediately after being turned on, it is possible to
begin capturing at once.
[0019] (2) In the multi-projection display according to an
exemplary aspect of the invention (1), the solid-state light source
may be an LED light source, a semiconductor laser light source, a
solid-state laser light source, or an EL light source.
[0020] Thus, a multi-projection display in which is easy to adjust
since the stable turned-on state is acquired at once and which has
sufficient brightness and color-rendering property is acquired.
[0021] (3) In the multi-projection display according to exemplary
aspects of the invention (1) or (2), the unit image information
correcting unit may correct the unit image information based on a
result of capturing adjusting unit images projected by the
projector units.
[0022] The unit image information correcting unit may perform the
correction of the unit image information based on a capturing
result of a related art image. However, by correcting the unit
image information based on the result of capturing the adjusting
unit image, it is possible to perform the more accurate correction
rapidly.
[0023] As the adjusting unit image, various unit images suitable to
perform the correction of the unit image information, such as a
beta image of white or monochrome, a lattice shape of monochrome,
may be used.
[0024] In this case, it may be constructed such that the adjusting
image information is previously stored in the multi-projection
display and the unit image information generating unit generates
the adjusting unit image using the adjusting image information at
the time of the adjustment operation. In addition, the adjusting
unit image information may be previously stored in the
multi-projection display and at the time of the adjustment
operation, the adjusting unit image information may be used as it
is.
[0025] Further, when the adjustment operation is performed, the
adjusting image information may be input to the multi-projection
display (a DVD or the like) and the unit image information
generating unit may generate the adjusting unit image information
using the adjusting image information. Further, when the adjustment
operation is performed, the adjusting unit image information may be
input directly to the multi-projection display.
[0026] (4) In the multi-projection display according to any
exemplary aspect of the invention (1) to (3), the unit image
information correcting unit may correct shapes, positions and/or
inclinations of unit images to be projected by the projector
units.
[0027] If doing so, the shapes, the positions and/or the
inclinations of the projection images from the respective projector
units become proper. Thus it is possible to highly match the
projection images from the respective projector units.
[0028] (5) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (3), the unit image
information correcting unit may correct the brightness and/or
colors of unit images to be projected by the projector units.
[0029] If doing so, the brightness and/or colors of the projection
images from the respective projector units become proper. Thus it
is possible to highly match the projection images from the
respective projector units.
[0030] (6) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (5), the unit image
information correcting unit may have a function of correcting the
brightness and/or color for every pixel in the plurality of
projector units.
[0031] If doing so, it is possible to further match the projection
images from the respective projector units, and thus it is possible
to project images true to original image information.
[0032] In this case, the unit image information correcting unit may
have a function of correcting the unit image to the brightness
and/or color for every pixel in the respective projector units by
comparing the adjusting image, which is formed by a plurality of
adjusting unit images to be projected by the plurality of projector
units, as a whole and an original adjusting image.
[0033] (7) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (6), the display may
include an image-capturing device for capturing the projection
images projected onto the screen.
[0034] If doing so, it is possible to shorten the time required for
capturing. Thus it is possible to drastically shorten the
adjustment operation time to match the projection images from the
respective projector units.
[0035] (8) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (7), the unit image
information correcting unit may correct the unit image information
using correction parameters that are determined based on the
capturing result.
[0036] If doing so, after the correction parameters are determined
once based on the capturing result, it is possible to easily
correct the unit image information using the correction
parameters.
[0037] (9) In the multi-projection display according to an
exemplary aspect of the invention (8), the display may include a
correction parameter storing unit to store the correction
parameters.
[0038] If doing so, it is possible to make the required storage
capacity smaller than when storing the capturing result itself.
Further, it is possible to make the calculation quantities, when
correcting the unit image information, small.
[0039] (10) In the multi-projection display according to exemplary
aspects of the invention (8) or (9), the display may include a
correction parameter automatic acquiring device to capture an
adjusting image in certain circumstances to automatically acquire
the correction parameters.
[0040] If doing so, for example, when the correction parameters are
needed to be determined again (Acquired again.) For example, three
months lapse after acquiring again), the correction parameter
automatic acquiring device may operate automatically to acquire the
correction parameters again. Further, when a regular time comes
(For example, at 4 a.m.), the correction parameter automatic
acquiring device may operate automatically to acquire the
correction parameters again. Thus, without troubling the user, it
is possible to maintain smooth image quality, and further
convenience is enhanced.
[0041] Further, even though the characteristics of the light source
or the electro-optical modulating device are changed by variation
per hour, the correction parameters corresponding to the change in
characteristic can be automatically acquired. Thus, it is possible
to constantly suppress deterioration of image quality due to the
variation per hour.
[0042] (11) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (10), the display may
include an optical correcting device to correct the position and/or
orientation of an optical element provided in the multi-projection
display.
[0043] If doing so, after the position and/or orientation of the
optical element is corrected once, smooth image quality is
acquired. Since the correction is optically performed, there is no
deterioration of image quality due to the adjustment operation.
[0044] In this case, after the optical correction to the position
and/or orientation of the optical element is first performed, the
capturing by the image-capturing device may be performed again.
Then the correction parameters are determined based on the
capturing result.
[0045] If doing so, after optically performing the large scale
correction first, it is possible to perform the minute correction
purely electronically. Further, it is possible to suppress
deterioration of image quality to be generated when the unit image
information correcting unit corrects the unit image information to
a minimum.
[0046] (12) In the multi-projection display according to exemplary
aspect of the invention (11), the display may include an optical
element automatic correcting device to capture an adjusting image
in certain circumstances to automatically correct the position
and/or orientation of the optical element.
[0047] If doing so, for example, when the correction parameters are
needed to be determined again (Acquired again.) (For example, three
months lapse after acquiring again) or when the regular time comes
every day (For example, at 4 a.m.), the correction parameter
automatic acquiring device may operate automatically to correct the
position and/or orientation of the optical element. Thus, without
troubling the user, it is possible to maintain smooth image
quality, and further convenience is enhanced.
[0048] (13) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (12), the display may
include a solid-state light source control unit to control the
amount of light emitted from the solid-state light source
separately for every projector unit.
[0049] In the multi-projection display, generally, due to
unevenness in characteristic in the light source or the
electro-optical modulating device, it is the present situation that
a brightness characteristic or a color characteristic for every
projector unit is different. For this reason, in the
multi-projection display, a voltage to be applied to the
electro-optical modulating device for every projector unit is
adjusted such that the difference of the brightness characteristics
or the color characteristics is absorbed. As a result, in the
multi-projection display, by performing the adjustment, the
gradation source is needed to be used in the electro-optical
modulating device, which results in problems in that the number of
effective gradations inherent in the multi-projection display is
lowered or the dynamic range becomes narrow.
[0050] According to the multi-projection display of an exemplary
aspect of the invention (13), by controlling the amount of light
emitted from the solid-state light source for every projector unit,
it is possible to absorb the difference of the brightness
characteristics or the color characteristics. For this reason,
according to the multi-projection display of an exemplary aspect of
the present invention, since there is no need to use the gradation
source in the electro-optical modulating device, there is no case
in which the number of effective gradations inherent in the
multi-projection display is lowered or the dynamic range becomes
narrow.
[0051] In this case, in order to absorb the difference of the
brightness characteristic for every projector unit, in the
projector units other than the projector unit having the lowest
brightness level, the amount of light emitted from the solid-state
light source may be lowered such that the brightness level in the
projector units complies with the brightness level in the projector
unit having the lowest brightness level.
[0052] Further, in order to absorb the difference of the color
characteristic for every projector unit, the above-mentioned
adjustment may be performed for every color light component.
[0053] Moreover, in the multi-projection display of the exemplary
aspect of the invention (13), unlike a case in which the high
pressure mercury lamp or the metal halide lamp is used as the light
source, while the amount of emitted light decreases or increases as
the voltage decreases or increase, the color temperature is not
almost changed. Thus, there is no deterioration of image
quality.
[0054] In the multi-projection display of the exemplary aspect of
the invention (13), the solid-state light source control unit may
have a function of controlling separately the voltage to be
supplied to the solid-state light source for every projector
unit.
[0055] If doing so, it is possible to easily increase or decrease
the amount of light emitted from the solid-state light source for
every projector unit.
[0056] In the multi-projection display of the exemplary aspect of
the invention (13), the solid-state light source control unit may
have a function of controlling separately the pulse width of
alternating current (AC) power to be supplied to the solid-state
light source for every projector unit.
[0057] If doing so, it is possible to easily increase or decrease
the amount of light emitted from the solid-state light source for
every projector unit.
[0058] (14) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (13), the
multi-projection display may be a rear surface projection type
multi-projection display which may include a transmissive screen to
project the projection images from the plurality of projector
units.
[0059] In this case, since it is possible to drastically shorten
the above-mentioned adjustment time, it is possible to drastically
shorten the time required for an assembling operation when the
multi-projection display is assembled into the housing. Thus, it is
possible to easily reduce the cost of the product. Further, when
the maintenance of the multi-projection display is performed, it is
possible to drastically shorten the time required for the
maintenance operation. Thus convenience of the user is
enhanced.
[0060] Moreover, in this case, the image-capturing device may be
arranged in the housing of the multi-projection display.
[0061] If doing so, once if the image-capturing device is arranged
surely in the housing of the rear surface projection type
multi-projection display, there is no need to put the
image-capturing device in order after the adjustment operation is
completed. Thus, there is no need to set up the image-capturing
device again when the projection image is captured. As a result,
the adjustment operation becomes easy and the adjustment time is
also shortened. Further, there are advantages that the
image-capturing element can be easily set up at an accurate
position to the transmissive screen, and the capturing of the
projection image can be performed accurately and easily. In
addition, there are advantages that the overall control unit to
process the capturing result can be easily housed in the housing
and the multi-projection display can be easily moved and set
up.
[0062] (15) In the multi-projection display according to any one of
the exemplary aspects of the invention (1) to (13), the
multi-projection display may be a front surface projection type
multi-projection display which projects the projection images from
the projector units onto a front surface thereof.
[0063] In this case, since it is possible to drastically shorten
the above-mentioned adjustment time, it becomes possible to
drastically shorten the time required for the adjustment operation
when the multi-projection display is set up.
[0064] The present inventors has discovered that by using the
solid-state light source as the light source of the
multi-projection display and by performing the adjustment operation
using light from the solid-state light source, the above-mentioned
and/or other advantages can be obtained. However, the present
inventors has also discovered that by using the solid-state light
source as the light source of the multi-projection display and by
controlling the amount of light emitted from the solid-state light
source for every projector unit, other excellent advantages can be
obtained.
[0065] (16) Another multi-projection display of an exemplary aspect
of the present invention includes a plurality of projector units,
each having a solid-state light source to generate a plurality of
color light components, a plurality of electro-optical modulating
devices to modulate the plurality of color light components
respectively, and a projection optical system to project color
light components modulated by the plurality of electro-optical
modulating devices, a unit image information generating unit to
generate unit image information to be inputted to the plurality of
projector units respectively, and a solid-state light source
control unit to control the amount of light emitted from the
solid-state light source for every projector unit.
[0066] For this reason, according to another multi-projection
display of an exemplary aspect of the present invention, since it
is possible to control separately the amount of light emitted from
the solid-state light source for every projector unit, it is
possible to absorb the difference of the brightness characteristic
or the color characteristic for every projector unit by controlling
the amount of light emitted from the solid-state light source. For
this reason, since there is no need to use the gradation source in
the electro-optical modulating device, there is no case in which
the number of effective gradations inherent in the multi-projection
display is lowered or the dynamic range becomes narrow.
[0067] In this case, in order to absorb the difference of the
brightness characteristic for every projector unit, in the
projector units other than the projector unit having the lowest
brightness level, the amount of light emitted from the solid-state
light source may be lowered such that the brightness level in the
projector units complies with the brightness level in the projector
unit having the lowest brightness level.
[0068] Moreover, in the multi-projection display of the exemplary
aspect of the invention (16), unlike a case in which the high
pressure mercury lamp or the metal halide lamp is used as the light
source, while the amount of emitted light decreases or increases as
the voltage decreases or increase, the color temperature is not
almost changed. Thus, there is no deterioration of image
quality.
[0069] (17) In the multi-projection display according to the
exemplary aspect of the invention (16), the solid-state light
source control unit may have a function of controlling the amount
of light emitted from the solid-state light source for every
electro-optical modulating device.
[0070] If doing so, it is also possible to absorb the difference of
the color characteristic for every projector unit.
[0071] (18) In the multi-projection display according to the
exemplary aspects of the invention (16) or (17), the solid-state
light source control unit may have a function of dynamically
controlling the amount of light emitted from the solid-state light
source.
[0072] If doing so, in the case in which a totally dark screen is
displayed (For example, a case in which a night scene in a movie is
displayed), instead of or in addition to lowering the transmittance
of the electro-optical modulating device, by decreasing the amount
of light emitted from the solid-state light source, it is possible
to make an entire screen dark. Further, in the case in which a
totally bright screen is displayed (For example, a case in which an
outdoor scene in the daytime in a movie is displayed), instead of
or in addition to increasing the transmittance of the
electro-optical modulating device, by increasing the amount of
light emitted from the solid-state light source, it is possible to
make the entire screen bright. For this reason, it is possible to
increase the number of effective gradations or the dynamic range,
which results in a high image quality multi-projection display
having an excellent black level.
[0073] In this case, if the solid-state light source control unit
is allowed to dynamically control the amount of light emitted from
the solid-state light source, when an image in which a bright
screen and a dark screen exist in one screen is displayed, it is
possible for the multi-projection display to exhibit the expression
ability exceeding the number of effective gradation or the dynamic
range inherent in the multi-projection display. In addition, it is
possible to perform high image quality display.
[0074] (19) In the multi-projection display according to any one of
the exemplary aspects of the invention (16) to (18), the
solid-state light source control unit may have a function of
controlling a voltage to be supplied to the solid-state light
source for every projector unit or for every electro-optical
modulating device.
[0075] If doing so, it is possible to easily decrease or increase
the amount of light emitted from the solid-state light source for
every projector unit or for every electro-optical modulating
device.
[0076] (20) In the multi-projection display according to any one of
the exemplary aspects of the invention (16) to (18), the
solid-state light source control unit may have a function of
controlling an emitting period of the solid-state light source for
every projector unit or for every electro-optical modulating
device.
[0077] If doing so, it is also possible to easily decrease or
increase the amount of light emitted from the solid-state light
source for every projector unit or for every electro-optical
modulating device.
[0078] (21) In the multi-projection display according to the
exemplary aspect of the invention (20), the electro-optical
modulating device may be a liquid crystal device which writes one
unit screen information twice or more, and the solid-state light
source control unit may have a function of allowing the solid-state
light source to emit during one frame outside at least the first
writing period of the liquid crystal device.
[0079] In the multi-projection display using the liquid crystal
device as the electro-optical modulating device, since the liquid
crystal device is a hold type display device, unlike a case of a
CRT of an impulse type display device, there is a problem in that a
smooth moving picture display is not obtained due to a so-called
tailing phenomenon (As regards the tailing phenomenon, see "Image
Quality of Moving Picture Display in a Hold Type Display" IEICE
Technical Report, EID99-10, pages 55 to 60 (1999-06)).
[0080] According to the multi-projection display of exemplary
aspect of the invention (21), by performing writing twice or more
to one unit screen information, it is possible to make a flicker
inconspicuous. Further, a liquid crystal device of a so-called
n-time speed driving (Here, n is a natural number of 2 or more) is
used and the solid-state light source is allowed to emit outside at
least the first writing period of the liquid crystal device. Thus,
it becomes possible to project intermittently the projection images
onto the screen. For this reason, it is possible to alleviate the
tailing phenomenon which is a defect of the hold type display, and
further it is possible to perform moving picture display smoothly
with favorable quality.
[0081] Further, according to the multi-projection display of
exemplary aspect of the invention (21), the solid-state light
source is allowed to emit during one frame outside the first
writing period at which liquid crystal molecules do not yet
sufficiently response. Thus, there is also an advantage in that it
is possible to further improve contrast in the multi-projection
display.
[0082] (22) In the multi-projection display according to the
exemplary aspect of the invention (20), the electro-optical
modulating device may be a liquid crystal device which writes an
image sequentially for every screen region, and the solid-state
light source control unit may have a function of allowing the
solid-state light source to emit during one frame outside the image
writing periods of the liquid crystal device.
[0083] For this reason, according to the multi-projection display
of the exemplary aspect of the invention (22), during one frame or
the like, a liquid crystal device which is capable of making a
flicker inconspicuous by writing sequentially images for every
screen region is used, and the solid-state light source is allowed
to emit outside the image writing periods of the liquid crystal
device. Thus, it becomes possible to project intermittently the
projection images onto the screen. For this reason, it is possible
to alleviate the tailing phenomenon which is a defect of the hold
type display, and further it is possible to perform moving picture
display smoothly with favorable quality.
[0084] Further, according to the multi-projection display of the
exemplary aspect of the invention (22), the solid-state light
source is allowed to emit outside the image writing periods. Thus,
there is also an advantage in that it is possible to further
enhance contrast in the multi-projection display.
BRIEF DESCRIPTION OF THE DRAWINGS
[0085] FIGS. 1A and 1B are schematics showing a construction of a
multi-projection display according to a first exemplary
embodiment;
[0086] FIG. 2 is a schematic showing a construction of a projector
unit in the multi-projection display according to the first
exemplary embodiment;
[0087] FIG. 3 is a schematic showing an outline of the
multi-projection display according to the first exemplary
embodiment;
[0088] FIG. 4 is a schematic showing an outline of the
multi-projection display according to the first exemplary
embodiment;
[0089] FIG. 5 is a schematic showing an outline of the
multi-projection display according to the first exemplary
embodiment;
[0090] FIGS. 6(i)-6iii are schematics illustrating advantages of
the multi-projection display according to the first exemplary
embodiment;
[0091] FIG. 7 is a schematic illustrating advantages of the
multi-projection display according to the first exemplary
embodiment;
[0092] FIG. 8 is a schematic illustrating advantages of the
multi-projection display according to the first exemplary
embodiment;
[0093] FIG. 9 is a schematic illustrating advantages of the
multi-projection display according to the first exemplary
embodiment;
[0094] FIG. 10 is a schematic illustrating advantages of the
multi-projection display according to the first exemplary
embodiment;
[0095] FIG. 11 is a schematic illustrating advantages of the
multi-projection display according to the first exemplary
embodiment;
[0096] FIGS. 12A to 12C are schematics illustrating advantages of
the multi-projection display according to the first exemplary
embodiment;
[0097] FIG. 13 is a schematic showing a construction of a
multi-projection display according to a second exemplary
embodiment;
[0098] FIGS. 14(i)-14(iii) are schematics illustrating advantages
of the multi-projection display according to the second exemplary
embodiment;
[0099] FIG. 15 is a schematic showing an outline of the
multi-projection display according to a third exemplary
embodiment;
[0100] FIGS. 16A and 16B are schematics illustrating advantages of
the multi-projection display according to the third exemplary
embodiment;
[0101] FIG. 17 is a schematic illustrating an outline of the
multi-projection display according to a fourth exemplary
embodiment;
[0102] FIGS. 18A and 18B are schematics illustrating advantages of
the multi-projection display according to the fourth exemplary
embodiment;
[0103] FIGS. 19A and 19B are schematics illustrating advantages of
the multi-projection display according to a fifth exemplary
embodiment;
[0104] FIGS. 20A and 20B are schematics illustrating advantages of
the multi-projection display according to the fifth exemplary
embodiment;
[0105] FIG. 21 is a schematic illustrating advantages of the
multi-projection display according to a sixth exemplary
embodiment;
[0106] FIGS. 22A to 22C are schematics illustrating operations of
the multi-projection display according to a seventh exemplary
embodiment;
[0107] FIGS. 23A and 23B are schematics illustrating operations of
the multi-projection display according to an eighth exemplary
embodiment;
[0108] FIG. 24 is a schematic illustrating a construction of the
multi-projection display according to a ninth exemplary embodiment;
and
[0109] FIGS. 25A and 25B are schematics illustrating a construction
of the multi-projection display according to a tenth exemplary
embodiment.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
First Exemplary Embodiment
[0110] FIGS. 1A and 1B are schematics showing a construction of a
multi-projection display according to a first exemplary embodiment.
FIG. 1A is a cross-sectional view as viewed from a side and FIG. 1B
is a front view. FIG. 2 is a schematic showing a construction of a
projector unit in the multi-projection display according to the
first exemplary embodiment. FIGS. 3 to 5 are block schematics
showing an outline of the multi-projection display according to the
first exemplary embodiment.
[0111] A multi-projection display 100 according to the first
exemplary embodiment is a rear surface projection type in which the
projection images from four projector units 130 (In FIG. 1A, only
two projector units are shown) arranged in a housing 102 are
reflected by reflecting plates 104 to be projected onto a
transmissive screen 108, as shown in FIG. 1B. As shown in FIG. 2,
the respective projector units 130 include LED light sources 132R,
132G, and 132B as a solid-state light source, three liquid crystal
devices 134R, 134G, and 134B as an electro-optical modulating
device, a cross dichroic prism 136 and a projection lens 138.
Illumination light components from the LED light sources 132R,
132G, and 132B are modulated by the liquid crystal devices 134R,
134G, and 134B based on unit image information A.sub.1 to A.sub.n
(See FIG. 3) or adjusting unit image information B.sub.1 to B.sub.n
(See FIG. 4) and are projected by the projection lens 138.
[0112] The multi-projection display 100 according to the first
exemplary embodiment includes a control unit 110 having a unit
image information generating unit 120, a unit image information
correcting unit 150, an image processing unit 146 and an optical
correcting device 154, four projector units 130, an image-capturing
device 140, a video signal receiving unit 160, an adjusting image
information storing unit 122 and a correction parameter storing
unit 152, as shown in FIGS. 3 to 5.
[0113] The unit image information generating unit 120 has a
function of generating a plurality of unit image information
A.sub.1 to A.sub.n based on original image information A (see FIG.
3) and a function of generating the adjusting unit image
information B.sub.1 to B.sub.n based on the adjusting image
information B (See FIG. 4).
[0114] The image-capturing device 140 includes an image-capturing
element 142 to capture a predetermined region of an adjusting image
projected onto the transmissive screen 108 and an AD converting
element 144 to convert an analog signal from the image-capturing
element 142 into a digital signal.
[0115] The image processing unit 146 has a function of comparing a
result obtained by performing an image processing on the result
captured by the image-capturing device 140 with the adjusting image
information B to output the comparison result to the unit image
information correcting unit 150.
[0116] The unit image information correcting unit 150 has a
function of correcting unit image information based on the
capturing result by the image-capturing device 140 such that a
boundary between unit images to be projected by adjacent projector
units among the plurality of projector units 130 is not noticeable
on the transmissive screen 108. Thus, corrected unit image
information A.sub.1* to A.sub.n* are outputted to the respective
projector units 130 (See FIG. 5).
[0117] The correction parameter storing unit 152 has a function
storing correction parameters to be used when the unit image
information correcting unit 150 corrects unit image
information.
[0118] The adjusting image information storing unit 122 has a
function of storing information regarding adjusting images which
are objects to be captured by the image-capturing device 140.
[0119] According to the multi-projection display 100 of the first
exemplary embodiment, since the LED light sources 132R, 132G, and
132B which can acquire a stable emitting state immediately after
turning on, is used as a light source of the projector units 130,
it is possible to drastically shorten the time required until the
image-capturing device 140 captures the predetermined region of the
adjusting image to be projected onto the transmissive screen 108
for every projector unit 130. As a result, it is possible to
drastically shorten the adjustment operation time for matching the
projection images from the respective projector units 130. Thus
convenience is greatly enhanced.
[0120] Further, according to the multi-projection display 100 of
the first exemplary embodiment, since the LED light sources 132R,
132G, and 132B can be freely set to a turned-on state or a
turned-off state, a shutter used in Japanese Unexamined Patent
Application Publication No. 2001-339672 is not needed. Since the
LED light sources 132R, 132G, and 132B are in the stable emitting
state immediately after being turned on, it is possible to begin
capturing at once. Further, no time is required to operate the
shutter. Thus it is also possible to further shorten the adjustment
time.
[0121] Further, according to the multi-projection display 100 of
the first exemplary embodiment, since the LED light sources 132R,
132G, and 132B are used as the solid-state light source, in
addition to the stable emitting state, the multi-projection display
has sufficient brightness and color-rendering property.
[0122] In the multi-projection display 100 according to the first
exemplary embodiment, as described above, the unit image
information correcting unit 150 corrects unit image information
based on the result of capturing the adjusting unit images.
[0123] The unit image information correcting unit 150 may correct
unit image information based on the result of capturing a general
image. However, in the present exemplary embodiment, by correcting
unit image information based on the result of capturing the
adjusting unit images, it is possible to correct more accurately
and rapidly.
[0124] As the adjusting unit image, various unit images suitable to
correct the unit image information, such as a beta image of white
or monochrome, a lattice shape of monochrome, may be used.
[0125] In this case, instead of previously storing the adjusting
image information in the adjusting image information storing unit
122 and generating the adjusting unit images by the unit image
information generating unit using the adjusting image information
at the time of the adjustment operation, the adjusting unit image
information may be previously stored and at the time of the
adjustment operation, and the adjusting unit image information may
be used as it is.
[0126] Further, when the adjustment operation is performed, the
adjusting image information may be input (By a DVD or the like) and
the unit image information generating unit may generate the
adjusting unit image information using the adjusting image
information. Further, when the adjustment operation is performed,
the adjusting unit image information may be directly input.
[0127] In the multi-projection display 100 according to the first
exemplary embodiment, the unit image information correcting unit
150 has a function of correcting the shapes, the positions and/or
the inclinations of the unit images to be projected by the
respective projector units 130. For this reason, the shapes, the
positions and/or the inclinations between the projection images
from the respective projector units 130 become proper. Thus it is
possible to highly match the projection images from the respective
projector units 130.
[0128] In the multi-projection display 100 according to the first
exemplary embodiment, the unit image information correcting unit
150 has a function of correcting the brightness and/or colors of
the unit images to be projected by the respective projector units
130. For this reason, the brightness and/or colors between the
projection images from the respective projector units 130 become
proper. Thus it is possible to highly match the projection images
from the respective projector units 130.
[0129] FIGS. 6 to 12 are schematics showing advantages of the
multi-projection display according to the first exemplary
embodiment.
[0130] With reference to FIGS. 3 to 12, how the multi-projection
display 100 according to the first exemplary embodiment may correct
the shapes, the positions and/or the inclinations between the
projection images from the respective projector units 130 will be
described. Further, how the brightness and/or colors between the
projection images from the respective projector units 130 may be
corrected will be described.
[0131] Display State Before Correcting
[0132] A display state before correcting will be described.
[0133] Referring to FIG. 3, if original image information A is
input from the video signal receiving unit 160 to the unit image
information generating unit 120, the unit image information
generating unit 120 generates unit image information A.sub.1 to
A.sub.n based on original image information A. The respective
projector units 130 project the unit images corresponding to unit
image information A.sub.1 to A.sub.n onto the transmissive screen
108. Therefore, on the transmissive screen 108, the projection
images according to the respective unit images from the respective
projector units 130 are projected. In this situation, since the
multi-projection display 100 is in a state before correcting, the
distorted projection images (I.sub.a0, I.sub.b0, I.sub.c0,
I.sub.d0) as shown in FIG. 6(i) are projected.
[0134] First Adjustment Operation
[0135] (An Adjustment Operation to the Shapes, the Positions and/or
the Inclinations of the Unit Images by the Optical Correcting Unit
154)
[0136] The first adjustment operation will now be described.
[0137] Referring to FIG. 4, if adjusting image information B from
the adjusting image information storing unit 122 is input to the
unit image information generating unit 120, the unit image
information generating unit 120 generates adjusting unit image
information B.sub.1 to B.sub.n based on adjusting image information
B. The respective projector units 130 project the unit images
corresponding to adjusting unit image information B.sub.1 to
B.sub.n onto the transmissive screen 108. In this situation, since
the multi-projection display 100 is in a state before correcting,
similar to the above description, since the multi-projection
display 100 is in a state before correcting, the distorted
projection images (I.sub.a0, I.sub.b0, I.sub.c0, I.sub.d0) as shown
in FIG. 6(i) are projected.
[0138] Next, with the image-capturing element 142 of the
image-capturing device 140, predetermined regions of the respective
projection images (I.sub.a0, I.sub.b0, I.sub.c0, I.sub.d0) relating
to the adjusting images shown in FIG. 6(i) are captured. And then,
the optical correcting device 154 optically corrects the position
and/or orientation of the housing of the respective projector units
130 based on the capturing result. Moreover, in exemplary aspects
of the present invention, instead of the housing of the projector
units 130, the position and/or orientation of the projection lens
138 of each of the projector units 130 or each of the reflecting
plates 104 may be optically corrected.
[0139] If adjusting image information B from the adjusting image
information storing unit 122 is inputted to the unit image
information generating unit 120 again, the respective projector
units 130 project the unit images corresponding to adjusting unit
image information B.sub.1 to B.sub.n onto the transmissive screen
108. In this situation, however, the position and/or orientation of
the housing of the respective projector units 130 are being
corrected based on the previous capturing result in the
multi-projection display 100. Thus, on the transmissive screen 108,
as shown in FIG. 6(ii), the projection images (I.sub.a1, I.sub.b1,
I.sub.c1, I.sub.d1) having reduced distortion are projected.
[0140] Second Adjustment Operation
[0141] (An Adjustment Operation to the Shapes, the Positions and/or
the Inclinations of the Unit Images by the Unit Image Information
Correcting Unit 150)
[0142] The second adjustment operation will now be described.
[0143] Next, with the image-capturing element 142 of the
image-capturing device 140, the respective projection images
(I.sub.a1, I.sub.b1, I.sub.c1, I.sub.d1) according to the adjusting
images shown in FIG. 6(ii) are captured. Then, based on the
capturing result, the unit image information correcting unit 150
determines the correction parameters to be used when unit image
information is corrected. Subsequently, the determined correction
parameters are stored in the correction parameter storing unit 152,
and then, based on the correction parameters, a plurality of unit
image information are generated from original image
information.
[0144] Thus, if original image information A is input from the
video signal receiving unit 160 to the unit image information
generating unit 120, the unit image information generating unit 120
generates unit image information based on original image
information A. In this situation, since unit image information is
corrected by the correction parameters, unit image information
A.sub.1* to A.sub.n* are generated. Therefore, the respective
projector units 130 project the unit images corresponding to unit
image information A.sub.1* to A.sub.n* onto the transmissive screen
108. In this situation, since the multi-projection display 100 is
already adjusted, as shown in FIG. 6(iii), the projection images
(I.sub.a2, I.sub.b2, I.sub.c2, I.sub.d2) from the respective
projector units 130 are aligned precisely.
[0145] Moreover, in the first adjustment operation and the second
adjustment operation, for example, as shown in FIG. 7 (A case in
which the inclinations between the respective unit images projected
exist) or FIG. 8 (A case in which the inclinations between the
respective unit images projected do not exist), the correction may
be performed such that reference lines of the adjusting images in
adjacent two projector units 130 comply with each other, or the
operation may be executed such that the reference line of the
adjusting image in one projector unit 130 is captured.
[0146] In both cases, it is needed to turn on only the light source
in adjacent two projector units 130 or it is needed to turn on only
the light source in one projector unit 130.
[0147] However, according to the multi-projection display 100 of
the first exemplary embodiment, since the LED light sources 132R,
132G, and 132B which can acquire the stable emitting state
immediately after turning on are used as the light source of the
respective projector units 130, it is possible to drastically
shorten the time required for the above-mentioned adjustment
operation.
[0148] Third Adjustment Operation
[0149] (An Adjustment Operation to Brightness and/or Colors of the
Unit Images by the Unit Image Information Correcting Unit 150)
[0150] The third adjustment operation will now be described. For
the purpose of simple description, an adjustment of an overlapped
region in adjacent two projector units (Temporarily, referred to as
PJU.sub.a and PJU.sub.b) will be described.
[0151] First, as shown in FIG. 9, a weight function in the
overlapped region is added to a pixel value of unit image
information such that the projection images (I.sub.a2, I.sub.b2)
from the adjacent projector units PJU.sub.a and PJU.sub.b are
connected smoothly to each other. In this situation, as the weight
function, as shown in FIG. 10, a weight function taking .gamma.
correction into consideration is used. By doing so, as shown in
FIG. 11, the projection images from the adjacent projector units
PJU.sub.a and PJU.sub.b are connected to each other. As a result,
as shown in FIGS. 12A to 12C, the projection images from the
adjacent two projector units are favorably synthesized and smoothly
connected to each other.
[0152] In the multi-projection display 100 according to the first
exemplary embodiment, when two unit image information are generated
based on original image information relating to an original image
(FIG. 12A), the unit images (FIG. 12B) are generated such that they
are smoothly connected to each other on the transmissive screen 108
(FIG. 12C). Thus, the projection images from the adjacent two
projector units PJU.sub.a and PJU.sub.b are favorably synthesized
and smoothly connected to each other.
[0153] In the multi-projection display 100 according to the first
exemplary embodiment, the unit image information correcting unit
150 has a function of correcting the brightness and/or color for
every pixel in the plurality of projector units 130.
[0154] For this reason, it is possible to highly match the
projection images from the respective projector units 130, and thus
it is possible to project an image extremely true to original image
information onto the screen.
[0155] In this case, the unit image information correcting unit 150
may have a function of correcting the unit image to the brightness
and/or color for every pixel in the respective projector units 130
by comparing all of the adjusting image, which are formed by a
plurality of adjusting unit images to be projected by the plurality
of projector units 130 with an original adjusting image.
[0156] The multi-projection display 100 according to the first
exemplary embodiment may include a correction parameter automatic
acquiring device to capture the adjusting image in certain
circumstances to automatically acquire the correction
parameters.
[0157] For this reason, for example, when the correction parameters
need to be determined again (Acquired again. For example, three
months lapse after acquiring again), the correction parameter
automatic acquiring device may operate automatically to acquire the
correction parameters again. Further, when the regular time comes
every day (For example, at 4 a.m.), the correction parameter
automatic acquiring device may operate automatically to acquire the
correction parameters again. Thus, without troubling the user, it
is possible to maintain smooth image quality, and further
convenience is enhanced.
[0158] Further, even though the characteristics of the LED light
sources 132R, 132G, and 132B or the liquid crystal devices 134R,
134G, and 134B are changed by variation per hour, the correction
parameters corresponding to the change in characteristic can be
automatically acquired. Thus, it is possible to constantly suppress
deterioration of image quality due to the variation per hour.
Second Exemplary Embodiment
[0159] FIG. 13 is a schematic showing a construction of a
multi-projection display according to a second exemplary
embodiment. FIG. 14 is a schematic illustrating advantages of the
multi-projection display according to the second exemplary
embodiment.
[0160] The multi-projection display 200 according to the second
exemplary embodiment is constructed such that an optical axis of a
projection light flux from each of the projector units 230 is
orthogonal to the screen surface of the transmissive screen 208, as
shown in FIG. 13.
[0161] For this reason, the unit images from the respective
projector units 230 do not have trapezoidal distortion. As a
result, advantages in the multi-projection display 200 according to
the second exemplary embodiment are as shown in FIG. 14, unlike
FIG. 6 showing advantages in the multi-projection display 100
according to the first exemplary embodiment.
[0162] However, in the multi-projection display 200 according to
the second exemplary embodiment, since the LED light sources (not
shown) which can acquire the stable emitting state immediately
after turning on (instantly turned on) are used as the light source
of the respective projector units 230. Thus, it is possible to
obtain the same advantages as those of the multi-projection display
100 according to the first exemplary embodiment.
Third Exemplary Embodiment
[0163] FIG. 15 is a block schematic showing an outline of a
multi-projection display according to the third exemplary
embodiment. FIGS. 16A and 16B are schematics illustrating
advantages of the multi-projection display according to the third
exemplary embodiment. FIG. 16A is a schematic showing advantages in
the case in which the unit image has trapezoidal distortion, and
FIG. 16B is a schematic showing advantages in the case in which the
unit image does not have trapezoidal distortion.
[0164] As shown in FIG. 15, the multi-projection display 300
according to the third exemplary embodiment has a construction of a
control unit different from the multi-projection displays 100 and
200 according to the first exemplary embodiment and the second
exemplary embodiment. That is, in the multi-projection display 300
according to the third exemplary embodiment, the control unit 112
has a construction excluding the optical correcting device 154 from
the construction of the control unit 110 in the multi-projection
display 100 and 200 according to the first exemplary embodiment and
the second exemplary embodiment.
[0165] However, in the multi-projection display 300 according to
the third exemplary embodiment, the LED light sources (not shown)
which can acquire the stable emitting state immediately after
turning on (instantly turned on) are used as the light source of
the respective projector units 130. Thus, it is possible to obtain
the same advantages as those of the multi-projection display 100
and 200 according to the first exemplary embodiment and the second
exemplary embodiment.
[0166] Further, the multi-projection display 300 according to the
third exemplary embodiment can correct the unit images without
using the optical correcting device. Thus, it is possible to
simplify the structure. Further, it has an advantage in that it is
possible to reduce design costs and enhance reliability. In
particular, the multi-projection display 300 can be suitably used
as a rear surface projection type multi-projection display in which
the projector units are fixedly arranged in the housing.
[0167] Moreover, in the multi-projection display 300 according to
the third exemplary embodiment, the unit image information is
corrected only by the working of the unit image information
correcting unit 150, without using the optical correcting device.
Thus, hereinafter, the adjustment method will be described.
[0168] Display State Before Correcting
[0169] Referring to FIG. 15, if original image information A is
inputted from the video signal receiving unit 160 to the unit image
information generating unit 120, the unit image information
generating unit 120 generates unit image information A.sub.1 to
A.sub.n based on original image information. The respective
projector units 130 project the unit images corresponding to unit
image information A.sub.1 to A.sub.n onto the screen. Therefore, on
the screen, the projection images relating to the respective unit
images from the respective projector units 130 are projected. In
this situation, since the multi-projection display 100 is in a
state before correcting, the distorted projection images (I.sub.a0,
I.sub.b0, I.sub.c0, I.sub.d0) as shown in FIG. 16A are
projected.
[0170] First Adjustment Operation
[0171] (An Adjustment Operation to the Shapes, the Positions and/or
the Inclinations of the Unit Images by the Unit Image Information
Correcting Unit 150)
[0172] The first adjustment operation will be described.
[0173] Next, if adjusting image information B is input from the
adjusting image information storing unit 122 to the unit image
information generating unit 120, the unit image information
generating unit 120 generates adjusting unit image information
B.sub.1 to B.sub.n (not shown) based on adjusting image information
B. The respective projector units 130 project the unit images
corresponding to adjusting unit image information B.sub.1 to
B.sub.n onto the screen. In this situation, since the
multi-projection display 300 is in a state before correcting,
similar to the above description, the distorted projection images
(I.sub.a0, I.sub.b0, I.sub.c0, I.sub.d0), as shown in FIG. 16A, are
projected.
[0174] Next, with the image-capturing element 142 of the
image-capturing device 140, the respective projection images
(I.sub.a0, I.sub.b0, I.sub.c0, I.sub.d0) relating to the adjusting
images shown in FIG. 16A are captured. Then, based on the capturing
result, the unit image information correcting unit 150 determines
the correction parameters to be used when unit image information is
corrected. Subsequently, the determined correction parameters are
stored in the correction parameter storing unit 152. Then, based on
the correction parameters, a plurality of unit image information
are generated from original image information.
[0175] Thus, if original image information A is input from the
video signal receiving unit 160 to the unit image information
generating unit 120, the unit image information generating unit 120
generates unit image information based on original image
information A. But in this situation, since unit image information
is corrected by the correction parameters, unit image information
A.sub.1* to A.sub.n* (not shown) are generated. Therefore, the
respective projector units 130 project the unit images
corresponding to unit image information A.sub.1* to A.sub.n* onto
the screen. In this situation, since the multi-projection display
300 is already adjusted, as shown in FIG. 16B, the projection
images (I.sub.a2, I.sub.b2, I.sub.c2, I.sub.d2) from the respective
projector units 130 are located precisely.
[0176] Second Adjustment Operation
[0177] (An Adjustment Operation to Brightness and/or Colors of the
Unit Images by the Unit Image Information Correcting Unit 150)
[0178] The second adjustment operation will be described. For the
purpose of simple description, an adjustment of an overlapped
region in adjacent two projector units (Temporarily, referred to as
PJU.sub.a and PJU.sub.b) will be described.
[0179] First, as shown in FIG. 9, a weight function in the
overlapped region is added to a pixel value of unit image
information such that the projection images (I.sub.a2, I.sub.b2)
from the adjacent projector units PJU.sub.a and PJU.sub.b are
smoothly connected to each other. In this situation, as the weight
function, as shown in FIG. 10, a weight function taking .gamma.
correction into consideration is used. By doing so, as shown in
FIG. 11, the projection images from the adjacent projector units
PJU.sub.a and PJU.sub.b are connected to each other. As a result,
as shown in FIGS. 12A to 12C, the projection images from the
adjacent two projector units are favorably synthesized and smoothly
connected to each other.
[0180] In the multi-projection display 300 according to the third
exemplary embodiment, when two unit image information is generated
based on original image information relating to an original image
(FIG. 12A), the unit images (FIG. 12B) are generated such that they
are smoothly connected to each other on the transmissive screen
(FIG. 12C). Thus, the projection images from the adjacent two
projector units PJU.sub.a and PJU.sub.b are favorably synthesized
and smoothly connected to each other.
Fourth Exemplary Embodiment
[0181] FIG. 17 is a schematic showing an outline of a
multi-projection display according to a fourth exemplary
embodiment. FIGS. 18 and 19 are schematics illustrating advantages
of the multi-projection display according to the fourth exemplary
embodiment. FIG. 18A shows a case in which the highest brightness
level white display is made in an entire screen of the
multi-projection display according to the first exemplary
embodiment. FIG. 18B shows a case in which the highest brightness
level white display is made in an entire screen of the
multi-projection display according to the fourth exemplary
embodiment.
[0182] As shown in FIG. 17, the multi-projection display 400
according to the fourth exemplary embodiment may include a
solid-state light source control unit 170 to control the amount of
emitted light of the LED light sources 132R, 132G, and 132B for
every projector unit 130, in addition to the construction of the
multi-projection display 100 according to the first exemplary
embodiment. The solid-state light source control unit 170 has a
function of controlling the amount of emitted light of the LED
light sources 132R, 132G, and 132B for every liquid crystal device
134R, 134G or 134B.
[0183] For this reason, the multi-projection display 400 according
to the fourth exemplary embodiment has the following advantages, in
addition to the advantages in the multi-projection display 100
according to the first exemplary embodiment.
[0184] According to the multi-projection display 400 of the fourth
exemplary embodiment, as shown in FIG. 18B, it is possible to
control separately the amount of emitted light of the LED light
sources 132R, 132G, and 132B for every projector unit 130. Thus, it
is possible to absorb the difference of the brightness
characteristics or the color characteristics for every projector
unit 130 by controlling the amount of emitted light of the LED
light sources 132R, 132G, and 132B. For this reason, as shown in
FIGS. 19A and 19B, there is no need to use the gradation source in
the electro-optical modulating device 134R, 134G, and 134B. Thus,
there is no case in which the number of effective gradations
inherent in the multi-projection display is lowered or the dynamic
range becomes narrow.
[0185] Further, according to the multi-projection display 400 of
the fourth exemplary embodiment, it is possible to control
separately the amount of emitted light of the LED light sources
132R, 132G, and 132B for every liquid crystal device 134R, 134G or
134B. Thus, it is also possible to absorb the difference of the
brightness characteristics or the color characteristics by
controlling the amount of emitted light of the LED light sources
132R, 132G, and 132B.
[0186] In the multi-projection display 400 according to the fourth
exemplary embodiment, as shown in FIG. 18B, in order to absorb the
difference of the brightness characteristic for every projector
unit 130, in the projector units (projector units projecting the
unit images Ia, Ib and Id) other than the projector unit having the
lowest brightness level (projector unit projecting the unit image
Ic), the amount of emitted light of the LED light sources is
lowered such that the brightness level in the projector units
complies with the brightness level in the projector unit having the
lowest brightness level.
[0187] In the multi-projection display 400 according to the fourth
exemplary embodiment, the amount of emitted light of the LED light
sources is controlled for every color light component.
[0188] In the multi-projection display 400 according to the fourth
exemplary embodiment, the solid-state light source control unit 170
may separately control voltages to be supplied to the LED light
sources 132R, 132G, and 132B or may separately control the emitting
periods of the LED light sources 132R, 132G, and 132B, for every
projector unit 130 and/or for every liquid crystal device 134R,
134G or 134B. In any cases, it is possible to easily decrease or
increase brightness of the LED light sources 132R, 132G, and
132B.
Fifth Exemplary Embodiment
[0189] FIGS. 20A and 20B are schematics illustrating advantages of
a multi-projection display according to a fifth exemplary
embodiment.
[0190] The multi-projection display 500 (not shown) according to
the fifth exemplary embodiment includes the solid-state light
source control unit 172 (not shown) to control the amount of
emitted light of the LED light sources 132R, 132G, and 132B for
every projector unit 130, similar to the multi-projection display
400 according to the fourth exemplary embodiment. Further, the
solid-state light source control unit 172 has a function of
controlling the amount of emitted light of the LED light sources
132R, 132G, and 132B for every liquid crystal device 134R, 134G or
134B, similar to the multi-projection display 400 according to the
fourth exemplary embodiment.
[0191] In the multi-projection display 500 according to the fifth
exemplary embodiment, the solid-state light source control unit 172
also has a function of dynamically controlling the amount of
emitted light of the LED light sources 132R, 132G, and 132B, in
addition to the above-mentioned function.
[0192] For this reason, the multi-projection display 500 according
to the fifth exemplary embodiment has the following advantages, in
addition to the advantages in the multi-projection display 400
according to the fourth exemplary embodiment.
[0193] As shown in FIG. 20B, in the case in which a totally dark
screen is displayed (for example, a case in which a night scene in
a movie is displayed), instead of or in addition to lowering the
transmittance of the liquid crystal devices 134R, 134G, and 134B,
by decreasing the amount of emitted light of the LED light sources
132R, 132G, and 132B, it is possible to make an entire screen dark.
Further, as shown in FIG. 20A, in the case in which a totally
bright screen is displayed (for example, a case in which an outdoor
scene in the daytime in a movie is displayed), instead of or in
addition to increasing the transmittance of the liquid crystal
devices 134R, 134G, and 134B, by increasing the amount of emitted
light of the LED light sources 132R, 132G, and 132B, it is possible
to make the entire screen bright.
[0194] For this reason, it is possible to increase the number of
effective gradations or the dynamic range, which results in a high
image quality multi-projection display having an excellent black
level.
Sixth Exemplary Embodiment
[0195] FIG. 21 is a schematic illustrating advantages of a
multi-projection display according to a sixth exemplary
embodiment.
[0196] The multi-projection display 600 (not shown) according to
the sixth exemplary embodiment includes the solid-state light
source control unit 174 (not shown) to control the amount of
emitted light of the LED light sources 132R, 132G, and 132B for
every projector unit 130 and for every liquid crystal device 134R,
134G or 134B, similar to the multi-projection display 500 according
to the fifth exemplary embodiment. Further, the solid-state light
source control unit 174 also has a function of dynamically
controlling the amount of emitted light of the LED light sources
132R, 132G, and 132B, similarly to the multi-projection display 500
according to the fifth exemplary embodiment.
[0197] In the multi-projection display 600 according to the sixth
exemplary embodiment, the solid-state light source control unit 174
also has a function of dynamically controlling the amount of
emitted light of the LED light sources 132R, 132G, and 132B for
every projector unit 130, in addition to the above-mentioned
function.
[0198] For this reason, the multi-projection display 600 according
to the sixth exemplary embodiment has the following advantages, in
addition to the advantages in the multi-projection display 500
according to the fifth exemplary embodiment.
[0199] That is, as shown in FIG. 21, in the case in which an image
in which a bright screen and a dark screen exist in one screen is
displayed, it is possible for the multi-projection display to
exhibit the expression ability exceeding the number of effective
gradation or the dynamic range inherent in the multi-projection
display. In addition, it is possible to perform high image quality
display.
Seventh Exemplary Embodiment
[0200] A multi-projection display 700 (not shown) according to the
seventh exemplary embodiment includes the solid-state light source
control unit 176 (not shown) to control the amount of emitted light
of the LED light sources 132R, 132G, and 132B for every projector
unit 130 and for every liquid crystal device 134R, 134G or 134B,
similar to the multi-projection display 600 according to the sixth
exemplary embodiment. Further, the solid-state light source control
unit 176 also has a function of dynamically controlling the amount
of emitted light of the LED light sources 132R, 132G, and 132B for
every projector unit 130.
[0201] The multi-projection display 700 according to the seventh
exemplary embodiment includes the liquid crystal devices 134R,
134G, and 134B (not shown), which perform writing twice or more to
one unit image information, as the liquid crystal device. Further,
in the multi-projection display 700 according to the seventh
exemplary embodiment, the solid-state light source control unit 176
has a function of allowing the solid-state light source to emit
during one frame outside at least the first writing period of the
liquid crystal devices 134R, 134G, and 134B.
[0202] FIGS. 22A to 22C are schematics illustrating operations of
the multi-projection display according to the seventh exemplary
embodiment. FIG. 22A shows a two-time speed driving liquid crystal
device, FIG. 22B shows a three-time speed driving liquid crystal
device, and FIG. 22C shows a four-time speed driving liquid crystal
device.
[0203] According to the multi-projection display 700 of the seventh
exemplary embodiment, as shown in FIGS. 22A to 22C, writing is
performed twice or more to one unit screen information, and a
liquid crystal device of a so-called n-time speed driving (here, n
is a natural number of 2 or more) is used. Further, the solid-state
light source is allowed to emit outside at least the first writing
period of the liquid crystal device. Thus, it becomes possible to
project intermittently the projection images onto the screen. For
this reason, it is possible to alleviate the tailing phenomenon
which is a defect of the hold type display, and further it is
possible to perform moving picture display smoothly with favorable
quality.
[0204] Further, in the first writing period, since the liquid
crystal molecules do not yet sufficiently respond, it is not easy
to raise contrast of the liquid crystal device. However, according
to the multi-projection display 700 of the seventh exemplary
embodiment, since the solid-state light source is allowed to emit
outside the first writing period, in the liquid crystal device and
the multi-projection display, it has an advantage that it is
possible to further enhance contrast.
Eighth Exemplary Embodiment
[0205] FIGS. 23A and 23B are schematics showing operations of a
multi-projection display according to an eighth exemplary
embodiment. The multi-projection display 800 (not shown) according
to the eighth exemplary embodiment includes the solid-state light
source control unit 178 (not shown) to control the amount of
emitted light of the LED light sources 132R, 132G, and 132B for
every projector unit 130 or for every liquid crystal device 134R,
134G or 134B, similarly to the multi-projection display 600
according to the sixth exemplary embodiment. Further, the
solid-state light source control unit 178 has a function of
dynamically controlling the amount of emitted light of the LED
light sources 132R, 132G, and 132B for every projector unit
130.
[0206] The multi-projection display 800 according to the eighth
exemplary embodiment includes the liquid crystal devices 134R,
134G, and 134B, which perform image writing sequentially for every
screen region during one frame, as the liquid crystal device.
Further, in the multi-projection display 800 according to the
eighth exemplary embodiment, the solid-state light source control
unit 178 has a function of allowing the LED light sources 132R,
132G, and 132B to emit during one frame outside the image writing
periods of the liquid crystal devices 134R, 134G, and 134B.
[0207] For this reason, according to the multi-projection display
800 of the eighth exemplary embodiment, the LED light sources 132R,
132G, and 132B are allowed to emit outside the image writing
periods of the liquid crystal devices 134R, 134G, and 134B. Thus,
it has an advantage that it is possible to further improve contrast
in the multi-projection display.
Ninth Exemplary Embodiment
[0208] FIG. 24 is a schematic showing a construction of a
multi-projection display according to a ninth exemplary
embodiment.
[0209] As shown in FIG. 24, the multi-projection display 900
according to the ninth exemplary embodiment is a front surface
projection type multi-projection display. However, since the LED
light sources (not shown) which can acquire the stable emitting
state immediately after being turned on are used as the light
source of the respective projector units 930, it is possible to
obtain the same advantages as those of the multi-projection display
100 according to the first exemplary embodiment.
Tenth Exemplary Embodiment
[0210] FIGS. 25A and 25B are schematics showing a construction of a
multi-projection display according to a tenth exemplary embodiment.
FIG. 25A is a cross-sectional view as viewed from a side, and FIG.
25B is a front view.
[0211] The multi-projection display 1000 according to the tenth
exemplary embodiment has almost the same construction as that of
the multi-projection display 100 according to the first exemplary
embodiment, but, as shown in FIGS. 25A and 25B, it is different
from the multi-projection display 100 according to the first
exemplary embodiment in that the image-capturing element 142 in the
image-capturing device is arranged in the housing 102 of the
multi-projection display 1000.
[0212] For this reason, the multi-projection display 1000 of the
tenth exemplary embodiment has the following advantages, in
addition to the advantages in the multi-projection display 100
according to the first exemplary embodiment.
[0213] If the image-capturing device is arranged surely in the
housing 102 of the multi-projection display 1000, there is no need
to put the image-capturing device in order after the adjustment
operation is completed. Thus, there is no need to set up the
image-capturing device again every time the projection image is
captured. As a result, the adjustment operation becomes easy and
the adjustment time is also shortened.
[0214] Further, there are advantages that the image-capturing
element 142 can be easily set up at an accurate position to the
transmissive screen 108, and the capturing of the projection image
can be performed accurately and easily.
[0215] In addition, there are advantages that the overall control
unit for processing the capturing result can be easily housed in
the housing 102 and the multi-projection display 1000 can be easily
moved and set up.
[0216] The multi-projection display of exemplary aspects of the
present invention is described based on the above-mentioned
respective exemplary embodiments. But the present invention is not
limited to the above-mentioned respective exemplary embodiments,
and it may be realized in various aspects within a scope without
departing from the subject matter of the present invention. For
example, the following modifications are possible.
[0217] (1) The multi-projection displays 100 to 1000 of the
above-mentioned respective exemplary embodiments use the LED light
source as the solid-state light source, but the present invention
is not limited to the LED light source, for example. Instead of the
LED light source, for example, a semiconductor laser light source,
a solid-state laser light source, or an EL light source may be
used.
[0218] Even in the case of using these solid-state light sources,
it is easy to adjust since the stable emitting state is acquired at
once. Further, it is possible to obtain the multi-projection
display having sufficient brightness and color-rendering
property.
[0219] (2) The multi-projection displays 100 to 1000 of the
above-mentioned respective exemplary embodiments use a transmissive
liquid crystal device as the electro-optical modulating device. But
the present invention is not limited to the transmissive liquid
crystal device. Instead of the transmissive liquid crystal device,
for example, a reflective liquid crystal device or a micromirror
type optical modulating device may be used.
[0220] Even in the case of using these electro-optical modulating
devices, similarly, it is possible to obtain the above-mentioned
advantages of the present invention.
* * * * *