U.S. patent application number 12/328371 was filed with the patent office on 2010-06-10 for magnetically actuated system.
This patent application is currently assigned to Microvision, Inc.. Invention is credited to Dean R. Brown, Matthew Ellis, Randall B. Sprague.
Application Number | 20100141366 12/328371 |
Document ID | / |
Family ID | 42230408 |
Filed Date | 2010-06-10 |
United States Patent
Application |
20100141366 |
Kind Code |
A1 |
Sprague; Randall B. ; et
al. |
June 10, 2010 |
Magnetically Actuated System
Abstract
A magnetically actuated system includes a conductor and a
magnetic field apparatus to generate a magnetic field. The magnetic
field apparatus includes magnets and magnetically permeable
materials to focus the magnetic field in areas of the conductor
that produce a drive torque when the conductor carries a
current.
Inventors: |
Sprague; Randall B.;
(Hansville, WA) ; Brown; Dean R.; (Lynnwood,
WA) ; Ellis; Matthew; (Austin, TX) |
Correspondence
Address: |
MICROVISION, INC.
6222 185TH AVENUE NE
REDMOND
WA
98052
US
|
Assignee: |
Microvision, Inc.
Redmond
WA
|
Family ID: |
42230408 |
Appl. No.: |
12/328371 |
Filed: |
December 4, 2008 |
Current U.S.
Class: |
335/219 |
Current CPC
Class: |
H01F 7/066 20130101;
H04N 9/312 20130101; G02B 26/085 20130101; H04N 9/3129 20130101;
G02B 26/101 20130101 |
Class at
Publication: |
335/219 |
International
Class: |
H01F 1/00 20060101
H01F001/00 |
Claims
1. An apparatus comprising: a first magnet oriented with a south
pole facing down and a north pole facing up; a second magnet
oriented parallel to the first magnet, the second magnet having a
north pole facing down and a south pole facing up; a third magnet
between, and oriented perpendicular to, the first and second
magnets, the third magnet having a south pole facing the second
magnet and a north pole facing the first magnet; and a movable
platform having a conductive coil nominally oriented in a platform
plane above the first, second, and third magnets.
2. The apparatus of claim 1 wherein the movable platform includes a
gimballed structure allowing the movable platform to rotate out of
the platform plane on a first axis, the movable platform further
including a reflective part that can rotate relative to the
gimballed structure on a second axis substantially 90 degrees from
the first axis.
3. The apparatus of claim 2 wherein the third magnet orientation is
misaligned with respect to the first and second axes of the movable
platform.
4. The apparatus of claim 1 further comprising: a fourth magnet
above the first magnet and the platform plane, the fourth magnet
having a south pole facing up and a north pole facing down; and a
fifth magnet above the second magnet and the platform plane, the
fifth magnet having a south pole facing down and a north pole
facing up.
5. The apparatus of claim 4 further comprising: at least one
focusing plate of magnetically permeable material positioned
between the platform plane and the fourth and fifth magnets to
focus a resulting magnetic field in the platform plane.
6. An apparatus comprising: a first magnet oriented with a south
pole facing down and a north pole facing up; a second magnet
oriented parallel to the first magnet, the second magnet having a
north pole facing down and a south pole facing up; a movable
platform having a conductive coil nominally oriented in a platform
plane above the first and second magnets; and a magnetically
permeable core beneath the movable platform and between the first
and second magnets.
7. The apparatus of claim 6 wherein the movable platform includes a
gimballed structure allowing a portion of the movable platform to
rotate out of the platform plane on two separate axes substantially
90 degrees apart.
8. The apparatus of claim 7 wherein the conductive coil has an
inner outline and the magnetically permeable core is oriented
beneath, and within the inner outline of, the conductive coil.
9. The apparatus of claim 8 wherein the inner outline of the
conductive coil is elliptical.
10. The apparatus of claim 6 further comprising: a third magnet
above the first magnet and the platform plane, the third magnet
having a south pole facing up and a north pole facing down; and a
fourth magnet above the second magnet and the platform plane, the
fourth magnet having a south pole facing down and a north pole
facing up.
11. The apparatus of claim 10 further comprising: at least one
focusing plate of magnetically permeable material positioned
between the platform plane and the third and fourth magnets to
focus a resulting magnetic field in the platform plane.
12. The apparatus of claim 11 wherein the conductive coil has an
outer outline and the focusing plates are shaped to be outside the
outer outline of the conductive coil.
13. An apparatus comprising: a first magnet oriented with a south
pole facing down and a north pole facing up; a second magnet
oriented parallel to the first magnet, the second magnet having a
north pole facing down and a south pole facing up; a movable
platform having a conductive coil nominally oriented in a platform
plane above the first and second magnets; a third magnet above the
first magnet and the platform plane, the third magnet having a
south pole facing up and a north pole facing down; a fourth magnet
above the second magnet and the platform plane, the fourth magnet
having a south pole facing down and a north pole facing up; and at
least one focusing plate of magnetically permeable material
positioned between the platform plane and the third and fourth
magnets to focus a resulting magnetic field in the platform
plane.
14. The apparatus of claim 13 wherein the movable platform includes
a reflective surface facing up, and the third and fourth magnets
are shaped to allow light to impinge on the reflective surface.
15. The apparatus of claim 13 wherein the conductive coil has an
outer outline and the focusing plates are shaped to be outside the
outer outline of the conductive coil.
16. The apparatus of claim 15 further comprising a magnetically
permeable core positioned between the first and second magnets and
beneath the movable platform.
17. A projection apparatus comprising: a light source to produce
light; a mirror to reflect the light, the mirror mounted on a
movable platform, the movable platform including a conductive coil;
at least one magnet to produce a magnetic field; and at least one
piece of magnetically permeable material positioned to modify the
magnetic field in the conductive coil.
18. The projection apparatus of claim 17 wherein the at least one
piece of magnetically permeable material includes two focusing
plates in a plane parallel to a plane of the conductive coil when
the movable platform is at rest.
19. The projection apparatus of claim 18 wherein the two focusing
plates are positioned on a first side of the movable platform in
common with the mirror, and wherein the at least one magnet
includes two magnets on an opposite side of the movable
platform.
20. The projection apparatus of claim 19 wherein the at least one
piece of magnetically permeable material further comprises a core
of material positioned between the two magnets on the opposite side
of the movable platform.
Description
FIELD
[0001] The present invention relates generally to magnetically
actuated systems, and more specifically to magnet field generation
used in magnetically actuated systems.
BACKGROUND
[0002] Magnetic actuation makes use of "Lorentz Forces" in which a
force on a current-carrying conductor is related to the current in
the conductor and the strength of a magnetic field across the
conductor. The force exerted is perpendicular to the direction of
the current in the conductor and perpendicular to the magnetic
field.
[0003] In magnetically actuated systems, power efficiency can be
gained by using larger magnets to create a stronger magnetic field.
The larger magnets, however, are heavier and increase volume
requirements of the resulting system. On the other hand, volume and
weight can be reduced by increasing the current in the conductor,
but this is at the expense of increased power consumption.
Accordingly, one can see that a trade-off exists between power
consumption and weight/volume in magnetically actuated systems.
[0004] It is desirable to reduce both power consumption and
weight/volume in magnetically actuated systems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 shows a cross-section of a magnetically actuated
system in accordance with various embodiments of the present
invention;
[0006] FIG. 2 shows a perspective view of a magnetically actuated
device having a movable platform with a conductive coil;
[0007] FIGS. 3-5 show perspective views of various magnetically
actuated systems with multiple magnets beneath a conductive
coil;
[0008] FIGS. 6-8 show magnetic fields in the magnetically actuated
system of FIG. 5;
[0009] FIGS. 9-11 show perspective views of various magnetically
actuated systems with multiple magnets and a magnetically permeable
core beneath a conductive coil;
[0010] FIGS. 12-14 show perspective views of various magnetically
actuated systems with multiple magnets and magnetic field focusing
plates;
[0011] FIGS. 15-17 show magnetic fields in the magnetically
actuated system of FIG. 14;
[0012] FIG. 18 shows a color laser projection apparatus; and
[0013] FIG. 19 shows a mobile device in accordance with various
embodiments of the present invention.
DESCRIPTION OF EMBODIMENTS
[0014] In the following detailed description, reference is made to
the accompanying drawings that show, by way of illustration,
specific embodiments in which the invention may be practiced. These
embodiments are described in sufficient detail to enable those
skilled in the art to practice the invention. It is to be
understood that the various embodiments of the invention, although
different, are not necessarily mutually exclusive. For example, a
particular feature, structure, or characteristic described herein
in connection with one embodiment may be implemented within other
embodiments without departing from the spirit and scope of the
invention. In addition, it is to be understood that the location or
arrangement of individual elements within each disclosed embodiment
may be modified without departing from the scope of the invention.
The following detailed description is, therefore, not to be taken
in a limiting sense, and the scope of the present invention is
defined only by the appended claims, appropriately interpreted,
along with the full range of equivalents to which the claims are
entitled. In the drawings, like numerals refer to the same or
similar functionality throughout the several views.
[0015] FIG. 1 shows a cross-section of a magnetically actuated
system in accordance with various embodiments of the present
invention. Magnetically actuated system 100 includes lower magnetic
field (B-field) apparatus 160, upper B-field apparatus 150, and
magnetically actuated device 110. Magnetically actuated device 110
includes a conductive coil seen in cross-section at 112. The upper
and lower B-field apparatuses produce a magnetic field across
conductive coil 112. The B-field is shown by arrows 120.
[0016] In some embodiments, lower B-field apparatus 160 includes
multiple magnets having various orientations. These magnets work
together to "focus" B-field 120 into an area of the conductive coil
where the resulting force will have the greatest effect. In other
embodiments, lower B-field apparatus 160 includes multiple magnets
and a magnetically permeable core to aid in focusing the resulting
B-field.
[0017] In some embodiments, upper B-field apparatus 150 includes
multiple magnets having various orientations, and in other
embodiments, upper B-field apparatus 150 includes multiple magnets
and "focusing plates" made of magnetically permeable material. The
various embodiments of the present invention combine different
permutations of magnets and magnetically permeable materials to
focus the B-field in areas of the conductive coil where greater
Lorentz forces are desired. These permutations are shown in, and
described below with reference to, FIGS. 3-17.
[0018] FIG. 2 shows a perspective view of a magnetically actuated
device having a movable platform with a conductive coil. Device 110
includes movable platform 240 and mirror 216. In embodiments
represented by FIG. 2, movable platform 240 is a gimballed
structure coupled to the frame of device 110 by flexures 210 and
212, and mirror 216 is coupled to movable platform 240 by flexures
220 and 222. Movable platform 240 has a conductive coil 112 capable
of carrying current. In some embodiments, flexures 210 and/or 212
include conductors to carry current to and from conductive coil
112.
[0019] Flexures 210 and 212 allow movable platform 240 to move in
one angular dimension (also referred to as a "drive axis").
Likewise, flexures 220 and 222 allow mirror 216 to move on a second
drive axis. In embodiments represented by FIG. 2, the two drive
axes are 90 degrees apart, but this is not a limitation of the
present invention.
[0020] In operation, various B-field apparatuses impose a magnetic
field 120 on conductive coil 112. The magnetic field imposed on the
conductive coil has a component in the plane of the coil, and is
oriented at roughly 45.degree. with respect to the two drive axes.
The in-plane current in the coil windings interacts with the
in-plane magnetic field to produce out-of-plane Lorentz forces on
the conductors. Since the drive current forms a loop on movable
platform 240, the current reverses sign across the drive axes. This
means the Lorentz forces also reverse sign across the drive axes,
resulting in a torque in the plane of and normal to the magnetic
field. This combined torque produces responses in the two scan
directions depending on the frequency content of the torque.
[0021] In embodiments represented by FIG. 2, one magnetic field is
used to produce angular movement of the mirror on both drive axes.
In order to cause movement of platform 240, the B-field 120 has a
component perpendicular to, and in the plane of, the conductive
coil 112. Furthermore, required drive power can be reduced if the
intensity of these in-plane perpendicular B-field vector components
are increased. The drive torque is related to the product of the
normal component of the magnetic B field and the coil drive
current. Thus, a 10% increase in B field will allow a 10% decrease
in current. Because the power required to drive the coil current is
related to the square of the current, a 10% increase in B field
will result in a 21% decrease in drive power.
[0022] The various embodiments of the present invention are
described relative to the magnetically actuated device shown in
FIG. 2. For example, as shown in FIG. 2, the conductive coil is
elliptical and on a gimballed movable platform with a mirror having
drive axes at substantially 90 degrees to the drive axes of the
movable platform. The various embodiments of the invention may be
utilized with any magnetically actuated device and are not limited
to the device as shown in FIG. 2. For example, magnet assemblies
and magnetically actuated systems described below can be utilized
to provide a Lorentz force on any conductor having any shape on any
movable platform.
[0023] FIG. 3 shows a perspective view of a magnetically actuated
system with multiple magnets beneath a conductive coil. Conductive
coil 112 is shown "floating" above the rest of the assembly to
provide a visual indication of where the coil resides in a complete
system. The remaining details of the magnetically actuated device
(e.g., device 110, FIGS. 1, 2) have been omitted from FIG. 3 so as
not to obscure the remainder of the figure. This convention is also
followed in many of the remaining figures.
[0024] Conductive coil 112 is said to be nominally in a "platform
plane." When the conductive coil is at rest, it is in the platform
plane, and when it is moving, it may have an angular displacement
relative to the platform plane. This terminology has been selected
to refer to the plane in which the coil resides, and is not meant
to imply any further structural limitations. Further, various
embodiments are described using terms such as "above," "below,"
"up," "down," etc. These terms have been selected to allow the
description of relative placement and orientation of components and
are not meant to imply any absolute orientation.
[0025] Magnets 310, 320, and 330 form a lower B-field apparatus
such as lower B-field apparatus 160 (FIG. 1). Magnets 310, 320, and
330 are permanent magnets situated beneath conductive coil 112, and
having various magnetic orientations. For example, magnet 310 has a
north pole facing down and a south pole facing up; magnet 320 is
oriented parallel to magnet 310 with a north pole facing up and a
south pole facing down; and magnet 330 is between, and oriented
perpendicular to, magnets 310 and 320 with a north pole facing
magnet 320 and south pole facing magnet 310. Magnets 310 and 320
are oriented perpendicular to the platform plane, whereas magnet
330 is oriented parallel to the platform plane.
[0026] In some embodiments, conductive coil 112 is on a gimballed
structure (240, FIG. 2) allowing the conductive coil 112 to rotate
relative to the platform plane on a first axis, and the gimballed
structure includes a reflective part (mirror 216, FIG. 2) that can
rotate relative to the gimballed structure on a second axis.
[0027] In some embodiments, magnet 330 is oriented such that it is
misaligned with respect to the two axes of the movable platform.
For example, as shown in FIG. 3, conductive coil 112 is elliptical
in shape with the two drive axes on the major and minor ellipse
axes. Magnet 330, however, is oriented such that it does not align
with either of the drive axes. By intentionally misaligning magnet
330 with respect to the drive axes, the generated B-field can be
positioned to cross the conductive coil at a point in the ellipse
where drive torque is needed. See B-field 120 in FIG. 2.
[0028] Magnets 310 and 320 are shown generally having an "L" shape,
but this is not a limitation of the present invention. In some
embodiments, magnets 310 and 320 are triangular, and in other
embodiments, magnets 310 and 320 are rectangular. Magnets 310, 320,
and 330 are mounted to base plate 302. In some embodiments, base
plate 302 is made of a magnetically permeable material to aid in
"closing" the magnetic circuit, although this is not a limitation
of the present invention.
[0029] FIG. 4 shows a perspective view of the magnetically actuated
system of FIG. 3 with two additional magnets. Magnets 410 and 420
form an upper B-field apparatus such as upper B-field apparatus 150
(FIG. 1). Magnets 410 and 420 are placed above the platform plane
with magnetic orientations parallel to the magnetic orientation of
magnets 310 and 320. For example, magnet 410 has a south pole
facing down and a north pole facing up, and magnet 420 has a north
pole facing down and a south pole facing up.
[0030] Magnets 410 and 310 form a top/bottom magnet pair with south
poles facing each other, and magnets 320 and 420 form a top/bottom
magnet pair with north poles facing each other. As shown in later
figures, magnetic flux lines emerge from the north poles of magnets
320, 420, and 330, pass through the conductive coil, and enter the
south poles of magnets 310, 410, and 330.
[0031] Magnets 410 and 420 are oriented to allow light to enter
from above. In some embodiments, a reflective part (e.g., mirror
216, FIG. 2) is positioned within conductive coil 112, and is used
to reflect the light that enters from above. Magnets 410 and 420
are shown as "L" shaped, but this is not a limitation of the
present invention. In some embodiments, any shape that allows light
to enter may be used. In other embodiments, for example in
magnetically actuated systems not related to light reflection,
magnets 410 and 420 may be placed partially or completely above the
conductive coil.
[0032] FIG. 5 shows a perspective view of the magnetically actuated
system of FIG. 4 with the addition of a top plate. In some
embodiments, top plate 510 is made of a magnetically permeable
material to aid in "closing" the magnetic circuit, although this is
not a limitation of the present invention. Further, top plate 510
includes a hole above the conductive coil to allow light to enter.
In embodiments represented by FIG. 5, light can enter through the
hole in top plate 510 and be reflected at various angles that
depend on a current driven through the conductive coil.
[0033] FIGS. 6-8 show magnetic fields in the magnetically actuated
system of FIG. 5. FIG. 6 is a top view, and FIGS. 7 and 8 are side
views. In the top view of FIG. 6, magnetic flux lines in the
platform plane are shown. Accordingly, the arrows show the strength
and orientation of the magnetic field that contributes to drive
torque. As can be seen by the flux lines in FIG. 6, the magnetic
field is focused to provide the greatest drive torque in the upper
right corner and lower left corner of the conductive coil. This
corresponds to B-field 120 (FIG. 2).
[0034] FIGS. 7 and 8 show magnetic flux lines relative to the
platform plane. The platform plane is shown at 710. As can be seen
in FIGS. 7 and 8, the flux lines are substantially parallel to the
platform plane when crossing the conductive coil.
[0035] FIG. 9 shows a perspective view of a magnetically actuated
system with multiple magnets and a magnetically permeable core
beneath a conductive coil. Magnets 910 and 920 and core 930 form a
lower B-field apparatus such as lower B-field apparatus 160 (FIG.
1). Magnets 910 and 920 are permanent magnets situated beneath
conductive coil 112, and having opposite magnetic orientations. For
example, magnet 910 has a north pole facing down and a south pole
facing up; and magnet 920 is oriented parallel to magnet 910 with a
north pole facing up and a south pole facing down. Magnets 910 and
920 are oriented perpendicular to the platform plane.
[0036] Core 930 is made from a magnetically permeable material such
as steel. Core 930 is positioned between magnets 910 and 920
beneath the conductive coil. Conductive coil 112 has an inner
outline and an outer outline when viewed from above. In some
embodiments, when viewed from above, core 930 is entirely within
the inner outline of conductive coil 112. An example cross-section
that illustrates this relationship is shown in FIG. 15.
[0037] Core 930 provides a lower reluctance path for the magnetic
field, so the magnetic field passing through conductive coil 112
tends to enter and exit core 930 (and the inner outline of the
core) at closer to 90 degrees. This provides more drive torque for
a given magnetic field strength.
[0038] Magnets 910 and 920 are shown generally having an "L" shape,
but this is not a limitation of the present invention. In some
embodiments, magnets 910 and 920 are triangular, and in other
embodiments, magnets 910 and 920 are rectangular. Magnets 910 and
920 are mounted to base plate 902. In some embodiments, base plate
902 is made of a magnetically permeable material to aid in
"closing" the magnetic circuit, although this is not a limitation
of the present invention.
[0039] FIG. 10 shows a perspective view of the magnetically
actuated system of FIG. 9 with two additional magnets. Magnets 1010
and 1020 form an upper B-field apparatus such as upper B-field
apparatus 150 (FIG. 1). Magnets 1010 and 1020 are placed above the
platform plane with magnetic orientations parallel to the magnetic
orientation of magnets 910 and 920. For example, magnet 1010 has a
south pole facing down and a north pole facing up, and magnet 1020
has a north pole facing down and a south pole facing up.
[0040] Magnets 1010 and 910 form a top/bottom magnet pair with
south poles facing each other, and magnets 920 and 1020 form a
top/bottom magnet pair with north poles facing each other. As shown
in later figures, magnetic flux lines emerge from the north poles
of magnets 920 and 1020, pass through the conductive coil, and
enter the south poles of magnets 910 and 1010.
[0041] Magnets 1010 and 1020 are oriented to allow light to enter
from above. In some embodiments, a reflective part (e.g., mirror
216, FIG. 2) is positioned within conductive coil 112, and is used
to reflect the light that enters from above. Magnets 1010 and 1020
are shown as "L" shaped, but this is not a limitation of the
present invention. In some embodiments, any shape that allows light
to enter may be used. In other embodiments, for example in
magnetically actuated systems not related to light reflection,
magnets 1010 and 1020 may be placed partially or completely above
the conductive coil.
[0042] FIG. 11 shows a perspective view of the magnetically
actuated system of FIG. 10 with the addition of a top plate. In
some embodiments, top plate 1110 is made of a magnetically
permeable material to aid in "closing" the magnetic circuit,
although this is not a limitation of the present invention.
Further, top plate 1110 includes a hole above the conductive coil
to allow light to enter. In embodiments represented by FIG. 11,
light can enter through the hole in top plate 1110 and be reflected
at various angles that depend on a current driven through the
conductive coil.
[0043] FIG. 12 shows show a perspective view of a magnetically
actuated system with multiple magnets and magnetic field focusing
plates. FIG. 12 shows magnets 910 and 920, core 930, base plate
902, and conductive coil 112, all of which are described above with
reference to FIG. 9. FIG. 12 also shows focusing plates 1210 and
1220.
[0044] Focusing plates 1210 and 1220 are made from a magnetically
permeable material and placed at or above the platform plane
outside the outer outline of the conductive coil. This placement
provides a low reluctance path for the magnetic field near areas of
the coil where high B-field strength is desired.
[0045] As shown in FIG. 12, focusing plates 1210 and 1220 may be
used in conjunction with core 930, although this is not a
limitation of the present invention. For example, in some
embodiments, focusing plates 1210 and 1220 are used in systems that
do not include core 930. Also for example, in some embodiments,
focusing plates 1210 and 1220 are used in system with three magnets
beneath the platform plane, such as the embodiments shown in FIG.
3.
[0046] FIG. 13 shows magnets 1010 and 1020 placed above focusing
plates 1210 and 1220. The combination of magnets 1010 and 1020 and
focusing plates 1210 and 1220 form an upper B-field apparatus such
as upper B-field apparatus 150 (FIG. 1). Magnets 1010 and 1020 are
described above with reference to FIG. 10.
[0047] FIG. 14 shows top plate 1110 placed above magnets 1010 and
1020. Top plate 1110 is described above with reference to FIG. 11.
The difference between FIG. 11 and FIG. 14 is the addition of
focusing plates 1210 and 1220.
[0048] FIGS. 15-17 show magnetic fields in the magnetically
actuated system of FIG. 14. FIG. 15 is a top view, and FIGS. 16 and
17 are side views. In the top view of FIG. 15, magnetic flux lines
in the platform plane are shown. Accordingly, the arrows show the
strength and orientation of the magnetic field that contributes to
drive torque. As can be seen by the flux lines in FIG. 15, the
magnetic field is focused by the focusing plates and the permeable
core to be more perpendicular to the conductive coil in more
places. Accordingly, more of the available B-field contributes to
drive torque.
[0049] FIGS. 16 and 17 show magnetic flux lines relative to the
platform plane. The platform plane is shown at 710 just below the
focusing plates. As can be seen in FIGS. 16 and 17, the flux lines
are substantially parallel to the platform plane when crossing the
conductive coil.
[0050] FIG. 18 shows a color laser projection apparatus. System
1800 includes image processing component 1802, laser light sources
1810, 1820, and 1830. Projection system 1800 also includes mirrors
1803, 1805, and 1807, filter/polarizer 1850, magnetically actuated
system 100, mirror 216, driver 1892, and digital control component
1890.
[0051] In operation, image processing component 1802 receives video
data on node 1801, receives a pixel clock from digital control
component 1890, and produces commanded luminance values to drive
the laser light sources when pixels are to be displayed. Image
processing component 1802 may include any suitable hardware and/or
software useful to produce color luminance values from video data.
For example, image processing component 1802 may include
application specific integrated circuits (ASICs), one or more
processors, or the like.
[0052] Laser light sources 1810, 1820, and 1830 receive commanded
luminance values and produce light. Each light source produces a
narrow beam of light which is directed to mirror 216 via guiding
optics. For example, blue laser light source 1830 produces blue
light which is reflected off mirror 1803 and is passed through
mirrors 1805 and 1807; green laser light source 1820 produces green
light which is reflected off mirror 1805 and is passed through
mirror 1807; and red laser light source 1810 produces red light
which is reflected off mirror 1807. At 1809, the red, green, and
blue light are combined. The combined laser light is reflected off
filter/polarizer 1850 on its way to mirror 216. After reflecting
off mirror 216, the laser light passes through filter/polarizer
1850 to create an image at 1880.
[0053] In some embodiments, mirror 216 rotates on two axes in
response to electrical stimuli received on node 1893 from driver
1892. For example, mirror 216 (FIG. 2) rotates on two axes in
response to the interaction between current in conductive coil 112
and B-field 120.
[0054] Magnetically actuated system 100 may be any of the
embodiments described herein. For example, system 100 may include
any of the systems described with reference to FIGS. 3-17.
Projector 1800 is described as an example application, and the
various embodiments of the invention are not so limited. For
example, the compact magnet assemblies described herein may be used
with other mechanically actuated systems without departing from the
scope of the present invention.
[0055] FIG. 19 shows a mobile device in accordance with various
embodiments of the present invention. Mobile device 1900 may be a
hand held projection device with or without communications ability.
For example, in some embodiments, mobile device 1900 may be a
handheld projector with little or no other capabilities. Also for
example, in some embodiments, mobile device 1900 may be a device
usable for communications, including for example, a cellular phone,
a smart phone, a personal digital assistant (PDA), a global
positioning system (GPS) receiver, or the like. Further, mobile
device 1900 may be connected to a larger network via a wireless
(e.g., WiMax) or cellular connection, or this device can accept
data messages or video content via an unregulated spectrum (e.g.,
WiFi) connection.
[0056] Mobile device 1900 includes scanning projection device 1901
to create an image with light 1908. Similar to other embodiments of
projection systems described above, mobile device 1900 may include
a projector with one or more magnetically actuated systems
described above.
[0057] In some embodiments, mobile device 1900 includes antenna
1906 and electronic component 1905. In some embodiments, electronic
component 1905 includes a receiver, and in other embodiments,
electronic component 1905 includes a transceiver. For example, in
global positioning system (GPS) embodiments, electronic component
1905 may be a GPS receiver. In these embodiments, the image
displayed by scanning projection device 1901 may be related to the
position of the mobile device. Also for example, electronic
component 1905 may be a transceiver suitable for two-way
communications. In these embodiments, mobile device 1900 may be a
cellular telephone, a two-way radio, a network interface card
(NIC), or the like.
[0058] Mobile device 1900 also includes memory card slot 1904. In
some embodiments, a memory card inserted in memory card slot 1904
may provide a source for video data to be displayed by scanning
projection device 1901. Memory card slot 1904 may receive any type
of solid state memory device, including for example, Multimedia
Memory Cards (MMCs), Memory Stick DUOs, secure digital (SD) memory
cards, and Smart Media cards. The foregoing list is meant to be
exemplary, and not exhaustive.
[0059] Mobile device 1900 also includes data connector 1920. In
some embodiments, data connector 1920 can be connected to one or
more cables to receive analog or digital video data for projection
by scanning projection device 1901. In other embodiments, data
connector 1920 may mate directly with a connector on a device that
sources video data.
[0060] Although the present invention has been described in
conjunction with certain embodiments, it is to be understood that
modifications and variations may be resorted to without departing
from the scope of the invention as those skilled in the art readily
understand. Such modifications and variations are considered to be
within the scope of the invention and the appended claims.
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