PIXEL SHIFT DEVICE AND PROJECTOR

Abstract

To provide a pixel shifting device and a projector capable of improving rigidity of a frame at low cost without enlarging a device configuration.SOLUTION: A pixel shifting device comprises: an optical member; a first frame that holds the optical member and oscillates around a first oscillation axis; a second frame that is arranged on the periphery of the first frame, is coupled to the first frame, and oscillates around a second oscillation axis; a base that is arranged on the periphery of the second frame and is coupled to the second frame; a first actuator that oscillates the first frame with respect to the second frame; a second actuator that is provided in an area at a side at which the first actuator is arranged in the second frame, and oscillates the second frame with respect to the base; and a frame reinforcement member that is provided in an area as a side at which the first actuator and the second actuator are arranged in the second frame, and has a first surface having contact with a surface of the second frame.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a pixel shifting device and a projector. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there are projectors equipped with a pixel shift device that shifts the optical path of image light emitted from a light modulation device such as a liquid crystal panel (for example, see Patent Document 1 below). The pixel shift device in the above projector includes a first frame that holds an optical member, a second frame that is arranged around the first frame and connects the first frame, a base member that is arranged around the second frame and connects the second frame, a first actuator that oscillates the first frame relative to the second frame about a first oscillation axis, and a second actuator that oscillates the second frame about a second oscillation axis relative to the base member.

[0003] In the above pixel shift device, the first actuator and the second actuator are arranged together on one side along the axial direction of the second oscillation shaft, thereby adopting a layout that can efficiently cool the actuator, which is a heat source when driven. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-91343 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the pixel shift device, for example, the second frame can be more easily oscillated by using a lightweight material as a material for forming the second frame. However, in the pixel shift device, the first actuator and the second actuator are arranged in a concentrated manner on one side of the second frame, and therefore, the stress caused by the driving of the actuators is concentrated on one side of the second frame, which may affect durability. To address this, measures such as forming the second frame from a lightweight and high-strength material or increasing the second moment of area of ​​the second frame can be considered, but taking these measures will result in new problems such as increased costs, an increased size of the device configuration, or reduced workability. Therefore, there has been a demand for a new technology that can improve the rigidity of the frame without causing problems such as increased costs, an increased size of the device configuration, and reduced workability. [Means for solving the problem]

[0006] In order to solve the above problem, according to one embodiment of the present invention, there is provided a pixel shifting device comprising: an optical member; a first frame that holds the optical member and oscillates around a first oscillation axis; a second frame that is arranged around the first frame and connected to the first frame and oscillates around a second oscillation axis perpendicular to the first oscillation axis; a base that is arranged around the second frame and connected to the second frame; a first actuator that oscillates the first frame relative to the second frame between the first frame and the second frame; a second actuator that is provided in an area of ​​the second frame on the side where the first actuator is arranged and oscillates the second frame relative to the base; and a frame reinforcing member that is provided in an area of ​​the second frame on the side where the first actuator and the second actuator are arranged and has a first surface that contacts a surface of the second frame.

[0007] According to another aspect of the present invention, there is provided a projector comprising an image generating section that generates image light, a projection optical system that projects the image light, and an image shifting device of the above aspect that is arranged between the image generating section and the projection optical system and shifts the optical path of the image light from the image generating section. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating a schematic configuration of a projector according to an embodiment. [Diagram 2] 1 is an explanatory diagram showing the principle of increasing the resolution by shifting the optical path of image light; [Diagram 3] FIG. 2 is a plan view of a pixel shifting device. [Figure 4] 4 is a cross-sectional view taken along line IV-IV in FIG. 3. [Diagram 5] 4 is a diagram showing the positional relationship between a pixel shift device and an image generating unit. FIG. [Figure 6] FIG. 4 is a perspective view showing a configuration of a main part of a second frame. [Figure 7] 13 is an enlarged view showing a schematic configuration of a main part of a pixel shifting device according to a modified example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Note that the drawings used in the following description may show characteristic parts in an enlarged scale for the sake of convenience in order to make the characteristics easier to understand, and the dimensional ratios of each component may not necessarily be the same as in reality.

[0010] FIG. 1 is a diagram showing a schematic configuration of a projector according to the present embodiment. As shown in FIG. 1, a projector 1 of this embodiment includes a light source 2, a color separation optical system 3, an image generating section 4, a projection optical system 6, and a pixel shifting device .

[0011] Hereinafter, the positional relationship of each component may be explained using the XYZ coordinate system shown in the drawings. In each drawing, the Y axis is an axis along the projection direction of the image light LT onto the screen SCR in the projector 1. The X axis is an axis perpendicular to the Y axis and along the width direction of the screen SCR. The Z axis is an axis perpendicular to the X axis and Y axis and along the up-down direction of the screen SCR.

[0012] In this embodiment, for example, both directions along the Z axis are collectively referred to as the "up-down direction Z" in the projector 1, the direction toward the +Z direction is the "upper side," and the direction toward the -Z direction is the "lower side." Furthermore, both directions along the X axis are collectively referred to as the "left-right direction X" in the projector 1, the direction toward the +X direction is the "right side," and the direction toward the -X direction is the "left side." Furthermore, both directions along the Y axis are collectively referred to as the "front-rear direction Y" in the projector 1, the direction toward the +Y direction is the "front side," and the direction toward the -Y direction is the "rear side." Note that the up-down direction Z, the left-right direction X, and the front-rear direction Y are names used simply to explain the positional relationship of each component of the projector 1, and do not define the actual installation posture or orientation of the projector 1.

[0013] The light source 2 is configured with, for example, a laser light source, a wavelength conversion element, etc. The light source 2 collects blue laser light emitted from the laser light source as excitation light with a collecting lens, causes it to enter a wavelength conversion element containing a phosphor, and emits white light WL consisting of blue laser light and yellow fluorescence. Note that the light source 2 is not limited to a configuration using a laser light source and a wavelength conversion element, and may be configured to use, for example, a laser light source alone, an LED (Light Emitting Diode), or a discharge type light source lamp.

[0014] The image generating unit 4 has a light modulation device 4R that emits red image light, a light modulation device 4G that emits green image light, a light modulation device 4B that emits blue image light, and a light combining element 5. The image generating unit 4 modulates the light emitted from the light source 2 based on image information to generate image light LT.

[0015] The color separation optical system 3 includes a first dichroic mirror 7a, a second dichroic mirror 7b, a first reflecting mirror 8a, a second reflecting mirror 8b, a third reflecting mirror 8c, a relay lens 9a, and a relay lens 9b. The color separation optical system 3 separates the white light WL emitted from the light source 2 into red light LR, green light LG, and blue light LB.

[0016] The first dichroic mirror 7a separates the white light WL emitted from the light source 2 into red light LR, green light LG, and blue light LB. The first dichroic mirror 7a transmits the red light LR and reflects the green light LG and blue light LB. The second dichroic mirror 7b separates the mixed light of the green light LG and blue light LB into the green light LG and blue light LB. The second dichroic mirror 7b reflects the green light LG and transmits the blue light LB.

[0017] The first reflecting mirror 8a is disposed in the optical path of the red light LR. The first reflecting mirror 8a reflects the red light LR transmitted by the first dichroic mirror 7a toward the optical modulation device 4R. The second reflecting mirror 8b and the third reflecting mirror 8c are disposed in the optical path of the blue light LB. The second reflecting mirror 8b and the third reflecting mirror 8c guide the blue light LB transmitted by the second dichroic mirror 7b to the optical modulation device 4B.

[0018] The light modulation device 4G is composed of a green liquid crystal panel 4GP and polarizing plates (not shown) provided on the entrance side and exit side of the green liquid crystal panel 4GP. The light modulation device 4G has a first light exit surface 40G, and is disposed so that the first light exit surface 40G faces the projection optical system 6.

[0019] The light modulation device 4R is composed of a red liquid crystal panel 4RP and polarizing plates (not shown) provided on the entrance side and exit side of the red liquid crystal panel 4RP. The light modulation device 4R has a second light exit surface 40R, and is disposed facing the right side (+X) in the left-right direction X perpendicular to the front-rear direction Y in which the light modulation device 4G and the projection optical system 6 are aligned.

[0020] The light modulation device 4B is composed of a blue liquid crystal panel 4BP and polarizing plates (not shown) provided on the entrance side and exit side of the blue liquid crystal panel 4BP. The light modulation device 4B has a third light exit surface 40B, and is disposed so that the third light exit surface 40B faces the second light exit surface 40R of the light modulation device 4R. In other words, the light modulation device 4B is disposed so that the third light exit surface 40B faces the left side (-X) in the left-right direction X. In particular, in the projector 1 of this embodiment, in order to display brighter images, large panels are used as the liquid crystal panels 4RP, 4GP, and 4BP of the light modulation devices 4R, 4G, and 4B, as described above.

[0021] Hereinafter, the red liquid crystal panel 4RP, the green liquid crystal panel 4GP, and the blue liquid crystal panel 4BP may be collectively referred to as the liquid crystal panels 4RP, 4GP, and 4BP, respectively.

[0022] The light modulation device 4R modulates the red light LR of the white light WL emitted from the light source 2 using a red liquid crystal panel 4RP in response to an image signal. The light modulation device 4G modulates the green light LG of the white light WL emitted from the light source 2 using a green liquid crystal panel 4GP in response to an image signal. The light modulation device 4B modulates the blue light LB of the white light WL emitted from the light source 2 using a blue liquid crystal panel 4BP in response to an image signal. In this way, each of the light modulation devices 4R, 4G, and 4B generates image light corresponding to each color light.

[0023] A field lens 11R that collimates the red light LR that is incident on the optical modulation device 4R is disposed on the optical incident side of the optical modulation device 4R. A field lens 11G that collimates the green light LG that is incident on the optical modulation device 4G is disposed on the optical incident side of the optical modulation device 4G. A field lens 11B that collimates the blue light LB that is incident on the optical modulation device 4B is disposed on the optical incident side of the optical modulation device 4B.

[0024] The light combining element 5 is composed of a substantially cubic cross dichroic prism. The light combining element 5 combines the color lights emitted from the light emission surfaces 40R, 40G, and 40B of the light modulation devices 4R, 4G, and 4B to generate image light LT.

[0025] The projection optical system 6 is composed of a plurality of projection lenses. The projection optical system 6 enlarges and projects the image light LT synthesized by the image generating unit 4 onto the screen SCR. As a result, a color image is displayed on the screen SCR.

[0026] The pixel shift device 10 is disposed on the optical path of the image light LT between the light combining element 5 of the image generating unit 4 and the projection optical system 6. The projector 1 shifts the optical path of the image light LT using the pixel shift device 10, thereby causing a so-called pixel shift, and can display an image with a higher resolution than the resolution of each of the liquid crystal panels 4RP, 4GP, and 4BP on the screen SCR. For example, if each of the liquid crystal panels 4RP, 4GP, and 4BP is a full high-definition compatible liquid crystal panel, a 4K image can be displayed.

[0027] Here, the principle of increasing the resolution by shifting the optical path will be briefly explained with reference to Fig. 2. Fig. 2 is an explanatory diagram showing the principle of increasing the resolution by shifting the optical path of the image light LT. As described below, the pixel shifting device 10 has an optical member 20 which is a light-transmitting substrate that transmits the image light LT, and by changing the posture of this optical member 20, the optical path of the image light LT is shifted by utilizing refraction.

[0028] The pixel shift device 10 swings the optical member 20 in two directions: a first swing direction around a first swing axis J1 intersecting the optical axis AX, and a second swing direction around a second swing axis J2 intersecting the optical axis AX and the first swing axis J1. When the optical member 20 swings in the first swing direction, the optical path of the light incident on the optical member 20 shifts to a first direction F1 shown in FIG. 2. When the optical member 20 swings in the second swing direction, the optical path of the light incident on the optical member 20 shifts to a second direction F2 intersecting the first direction F1 shown in FIG. 2. As a result, the pixel Px displayed on the screen SCR is displayed at a position shifted in the first direction F1 and the second direction F2 intersecting the first direction F1. In this embodiment, the first direction F1 corresponds to the left-right direction X, and the second direction F2 corresponds to the up-down direction Z.

[0029] The projector 1 increases the apparent number of pixels by combining the shift of the optical path in the first direction F1 and the shift of the optical path in the second direction F2, thereby increasing the resolution of the image light LT projected on the screen SCR. For example, as shown in FIG. 2, the pixel Px is moved to a position shifted by 1 / 2 pixel in each of the first direction F1 and the second direction F2. This makes it possible to move the image display position on the screen SCR to an image display position P2 shifted by 1 / 2 pixel from the image display position P1 along the first direction F1, an image display position P3 shifted by 1 / 2 pixel from the image display position P1 along the first direction F1 and the second direction F2, and an image display position P4 shifted by 1 / 2 pixel from the image display position along the second direction F2. FIG. 2 shows the flow of the shift operation from A to B to C to D, focusing on a 1 / 4 region of the pixel Px.

[0030] As shown in Fig. 2, an optical path shift operation is performed so that an image is displayed at each of the image display positions P1, P2, P3, and P4 for a certain period of time, and the display contents of each of the liquid crystal panels 4RP, 4GP, and 4BP are changed in synchronization with the optical path shift operation. This allows pixels A, B, C, and D, which appear to be smaller than pixel Px, to be displayed. For example, if the pixels A, B, C, and D are displayed at a frequency of 60 Hz overall, it is necessary to cause each of the liquid crystal panels 4RP, 4GP, and 4BP to display at four times the speed corresponding to the image display positions P1, P2, P3, and P4. In other words, the display frequency, or so-called refresh rate, of each of the liquid crystal panels 4RP, 4GP, and 4BP is 240 Hz.

[0031] In the example shown in FIG. 2, the first direction F1 and the second direction F2 are mutually orthogonal directions, and are the arrangement directions of the pixels Px displayed in a matrix on the screen SCR. Instead of this configuration, the first direction F1 and the second direction F2 do not have to be mutually orthogonal directions, and may be inclined with respect to the arrangement direction of the pixels Px. Even in such a shift direction, the pixels Px can be moved to the image display positions P1, P2, P3, and P4 shown in FIG. 2 by appropriately combining the pixel shifts in the first direction F1 and the second direction F2. In addition, the shift amount of the image display position is not limited to 1 / 2 pixel, and may be, for example, 1 / 4 or 3 / 4 of the pixel Px.

[0032] Next, a description will be given of the configuration of the pixel shifting device 10. Fig. 3 is a plan view of the pixel shifting device 10. Fig. 3 is a plan view of the pixel shifting device 10 viewed from the -Y side toward the +Y side. As shown in FIG. 3, the pixel shifting device 10 includes an optical member 20, a first frame 21, a second frame 22, a base 23, a pair of first oscillation axis forming portions 24, a pair of first actuators 25, a pair of second actuators 26, and a frame reinforcing member 30. FIG. 3 shows a state in which the pixel shifting device 10 does not change the attitude of the optical member 20, that is, the pixel shifting device 10 is not in operation.

[0033] The pixel shift device 10 shifts the optical path of the image light LT according to the attitude of the optical member 20 on which the image light LT is incident from the image generation unit 4. The shift amount of the optical path of the image light LT is determined according to the degree of change in attitude of the optical member 20 (see FIG. 2).

[0034] The optical member 20 is a member that uses refraction to shift the optical path of the image light LT incident from the image generation unit 4. When the pixel shift device 10 is in a reference position where the incident angle of the image light LT with respect to the optical member 20 is 0°, the normal direction of the optical member 20 coincides with the front-rear direction Y.

[0035] For example, a substantially square white glass plate is used as the optical member 20. By using white glass plate having excellent strength, the rigidity of the entire optical member 20 is increased, so that distortion occurring in the optical member 20 can be suppressed. The material of the optical member 20 is not limited to white plate glass, but may be any material that is optically transparent and capable of refracting light, and may be various glass materials such as borosilicate glass and quartz glass. Alternatively, various crystal materials such as quartz and sapphire, and various resin materials such as polycarbonate resin and acrylic resin may be used. The shape of the optical member 20 is not limited to a substantially square shape, but may be a rectangle, a diamond, or an ellipse.

[0036] The first frame 21 is a frame that holds the optical member 20 and swings around a first swing axis J1. The first swing axis J1 of the first frame 21 is a virtual axis that passes through the center of the optical member 20 supported by the first frame 21.

[0037] The first frame 21 is a metallic frame in the shape of a picture frame, and is disposed around the optical member 20. The first frame 21 supports the outer periphery of the optical member 20, thereby housing the optical member 20 with its front and back surfaces exposed. The first frame 21 is made of a metal material having a predetermined rigidity, such as stainless steel. The optical member 20 is fixed to the first frame 21 by an adhesive. Note that the first frame 21 is not limited to a picture frame shape, and may be any member that supports at least a portion of the optical member 20.

[0038] The second frame 22 is a frame that oscillates around a second oscillation axis J2 perpendicular to the first oscillation axis. The second oscillation axis J2 of the second frame 22 is a virtual axis that is perpendicular to the first oscillation axis J1 and passes through the center of the optical member 20 supported by the first frame 21.

[0039] The second frame 22 is made of a plate material that is substantially octagonal in plan view, and has a substantially octagonal opening 222H. The first frame 21 that holds the optical member 20 is disposed inside the opening 22H of the second frame 22. That is, the second frame 22 is made of a frame-shaped member that surrounds the first frame 21, and is disposed around and connected to the first frame 21.

[0040] The second frame 22 is connected to the first frame 21 via a pair of first oscillation shaft forming portions 24. The second frame 22 is connected to the base 23 via a first connecting shaft portion 28b of a base connecting member 28 and a second connecting shaft portion 34b of a frame reinforcing member 30, which will be described later. The configurations of the pair of first oscillation shaft forming portions 24, the base connecting member 28, and the frame reinforcing member 30 will be described later. Based on this configuration, in the pixel shifting device 10 of this embodiment, the optical member 20 supported by the second frame 22 via the first frame 21 can change its posture by rotating around the second oscillation axis J2 relative to the base 23.

[0041] In this embodiment, the second frame 22 and the first frame 21 are arranged so that at least a portion of them overlap in the front-rear direction Y. That is, the second frame 22 and the first frame 21 are arranged so that at least a portion of them are on the same plane parallel to the XZ plane. Note that the second frame 22 may have a shape that surrounds the periphery of the first frame 21 when viewed in a plan view in the front-rear direction Y, and the position of the second frame 22 relative to the first frame 21 may be shifted in the front-rear direction Y. That is, the second frame 22 and the first frame 21 may be arranged so that their positions are shifted from each other in the front-rear direction Y.

[0042] The base 23 is made of a metal member such as aluminum, etc. The base 23 has an opening 230, a first second frame fixing portion 231, a second second frame fixing portion 232, and a pair of second coil holders 234.

[0043] The opening 230 is composed of a first opening 230a and a second opening 230b that communicate with each other. The second frame 22 is located inside the first opening 230a of the opening 230, and the frame reinforcing member 30 is located inside the second opening 230b of the opening 230. The first second frame fixing portion 231 fixes the base connecting member 28 located on the upper side (+Z) in the up-down direction Z of the second frame 22. The second frame fixing portion 232 fixes the frame reinforcing member 30 located on the lower side (−Z) in the up-down direction Z of the second frame 22. The pair of second coil holders 234 respectively hold the coils of a pair of second actuators 26 described later. The pair of second coil holders 234 are provided so as to face, respectively, a pair of second magnet holders 35 provided on a frame reinforcing member 30 described later in a direction perpendicular to the second oscillation axis J2 of the base 23. That is, the base 23 is disposed around the second frame 22 and is connected to the second frame 22 .

[0044] In this embodiment, the second frame 22 and the base 23 are disposed so as to overlap at least partially in the front-rear direction Y. That is, the second frame 22 and the base 23 are disposed so that at least a portion of each other is on the same plane parallel to the XZ plane. Note that the base 23 may have a shape that surrounds the periphery of the second frame 22 when viewed in a plan view in the front-rear direction Y, and the position of the base 23 relative to the second frame 22 may be shifted in the front-rear direction Y. That is, the second frame 22 and the base 23 may be disposed in a state in which their positions are shifted from each other in the front-rear direction Y.

[0045] The pair of first oscillation shaft forming parts 24 are disposed on both sides of the first frame 21 in the left-right direction X, which is a direction along the first oscillation axis J1, and connect the first frame 21 and the second frame 22. In the case of the present embodiment, the pair of first oscillation shaft forming parts 24 are formed integrally with the first frame 21, but the pair of first oscillation shaft forming parts 24 and the first frame 21 may be formed separately.

[0046] The pair of first oscillation shaft forming parts 24 are fixed to the surface 22b of the second frame 22 via screw members 223. The surface 22b of the second frame 22 faces the rear side (-Y) in the front-rear direction Y, and is the surface on the side where the image generating unit 4 is disposed with respect to the pixel shifting device 10.

[0047] In the pixel shifting device 10 of this embodiment, the pair of first oscillation shaft forming portions 24 are arranged symmetrically with respect to the second oscillation shaft J2. In this embodiment, the pair of first oscillation shaft forming portions 24 being arranged symmetrically means that each of the first oscillation shaft forming portions 24 has a similar shape, and when one forming portion is folded back with respect to the second oscillation shaft J2, it overlaps with the other forming portion. According to the pixel shifting device 10 of this embodiment, the first frame 21 and the second frame 22 are connected in a well-balanced manner by the pair of first oscillation shaft forming portions 24, so that the optical member 20 can be oscillated around the first oscillation shaft J1 in a stable state.

[0048] The pair of first oscillation shaft forming portions 24 has a pair of connecting shaft portions 240 and a pair of beams 241. The pair of connecting shaft portions 240 are located on the first oscillation axis J1 of the first frame 21, and connect the outer side surface 21a of the first frame 21 and the inside of the second frame 22 in a manner that allows the first frame 21 to swing. The pair of connecting shaft portions 240 respectively protrude from surfaces that face opposite to each other among the four outer side surfaces 21a of the rectangular frame-shaped first frame 21, and connect the first frame 21 and the second frame 22. Based on this configuration, in the pixel shift device 10 of this embodiment, the optical member 20 supported by the first frame 21 can rotate relative to the second frame 22 about the first oscillation axis J1 to change its posture.

[0049] The pair of beams 241 extend from each of the pair of connecting shaft portions 240 along the second oscillation axis J2 along the surface 22b of the second frame 22. The strength of the second frame 22 is increased at the portion where the pair of beams 241 are provided. According to the pixel shift device 10 of the present embodiment, by providing the beams 241 of the pair of first oscillation axis forming portions 24 on the surface 22b of the second frame 22, it is possible to increase the strength of the peripheral region of the connecting portion of the second frame 22 with the first frame 21.

[0050] In this embodiment, each of the pair of beams 241 is disposed so as to straddle the first oscillation axis J1. Each of the beams 241 is disposed on both sides of the first oscillation axis J1. In this embodiment, each of the pair of beams 241 is disposed symmetrically with respect to the first oscillation axis J1. Based on this configuration, the beams 241 of the first oscillation axis forming portion 24 can increase the strength of the portion of the second frame 22 extending in the up-down direction Z perpendicular to the first oscillation axis J1 in a well-balanced manner.

[0051] A first length L1 of each beam 241 in the vertical direction Z along the second oscillation axis J2 corresponds to a second length L2 of the first frame 21 in the vertical direction Z along the second oscillation axis J2. In this specification, the first length L1 and the second length L2 being corresponding means that the first length L1 and the second length L2 are substantially equal. Note that the first length L1 and the second length L2 being substantially equal includes not only a state in which the first length L1 and the second length L2 are completely equal, but also a state in which one of the first length L1 and the second length L2 is larger or smaller than the other by about several millimeters. Note that the first length L1 in the vertical direction Z of the beam 241 may be equal to the length in the vertical direction Z of the optical member 20 held by the first frame 21.

[0052] According to this configuration, a pair of beams 241 having a length equivalent to that of the first frame 21 are arranged overlapping on the second frame 22, thereby sufficiently increasing the rigidity of the second frame 22. Therefore, even when the pixel shift device 10 of the present embodiment uses the second frame 22 made of a thin and lightweight material, sufficient rigidity can be ensured for the second frame 22, thereby realizing a reduction in size and weight of the device itself.

[0053] 4 is a cross-sectional view of a main part of the pixel shift device 10. FIG 4 is a cross-sectional view taken along line IV-IV in FIG 3. As shown in FIG. 4, the pair of beams 241 extend in the vertical direction Z along the second oscillation axis J2, rise along the front-to-rear direction Y which is the normal direction of the surface 22b of the second frame 22, and have a standing wall portion 243 which extends in the vertical direction Z along the second oscillation axis J2.

[0054] The standing wall portion 243 is provided at the end portion 241a of each of the pair of beams 241 on the base 23 side. In the case of this embodiment, the standing wall portion 243 extends toward the projection optical system 6 along the outer surface 22c of the second frame 22. By providing the standing wall portion 243, the pair of beams 241 have a cross section along the XY plane that is substantially L-shaped, and the second moment of area can be increased compared to a structure without the standing wall portion 243. Therefore, the pair of beams 241 can increase the rigidity of the second frame 22 while minimizing the first length L1 in the vertical direction Z. Therefore, the pixel shift device 10 of this embodiment can efficiently increase the rigidity of the second frame 22 while suppressing an increase in weight by suppressing the length of the pair of beams 241.

[0055] 3, when viewed in a plan view in the front-rear direction Y which is the normal direction of the surface 22b of the second frame 22, both end portions 245 of each of the pair of beams 241 in the up-down direction Z along the second oscillation axis J2 have oblique sides 246 whose length in the up-down direction Z increases from the first frame 21 side toward the base 23 side. That is, both end portions 245 of each of the beams 241 have a shape in which the width in the up-down direction Z increases in a tapered manner from the inside to the outside of the second frame 22 due to the oblique sides 246.

[0056] The inventors performed a simulation in which the planar shape of each of the beams 241 was rectangular, that is, in which both ends of each of the beams 241 were not tapered. This simulation confirmed that making the planar shape of each of the beams 241 rectangular did not contribute to the rigidity of each of the beams 241. In contrast to this, in the pixel shifting device 10 of the present embodiment, by providing the oblique sides 246 at both ends 245 of each beam 241 as described above, it is possible to reduce the weight of each beam 241 while ensuring the rigidity of each beam 241.

[0057] Here, the resonance frequency of the second frame 22 changes depending on the length of the pair of beams 241. In the pixel shift device 10 of this embodiment, the length of the pair of beams 241 is appropriately adjusted to set the resonance frequency of the second frame 22 to a desired value. Specifically, in the pixel shift device 10 of this embodiment, the length of the pair of beams 241 is appropriately adjusted to shift the resonance frequency of the second frame 22 to a high frequency. This makes it possible to suppress the occurrence of resonance in the second frame 22 without increasing the size or thickness. Therefore, according to the pixel shift device 10 of this embodiment, it is possible to provide a highly reliable pixel shift device in which the occurrence of problems due to resonance is suppressed while miniaturizing the device configuration.

[0058] In this manner, in the pixel shift device 10 of this embodiment, a pair of beams 241 of a pair of first oscillation axis forming portions 24 connecting the first frame 21 and the second frame 22 are formed along the surface 22b of the second frame 22, thereby increasing the strength of the second frame 22 on which each beam 241 is arranged.

[0059] The pair of first oscillation axis forming portions 24 include beams 241 extending from a connecting axis portion 240 that connects the first frame 21 and the second frame 22, which support the optical element 20 on the first oscillation axis J1, onto the surface 22b of the second frame 22 in the vertical direction Z along the second oscillation axis J2, thereby efficiently increasing the strength of the second frame 22 in the vicinity of the connecting portion with the first frame 21.

[0060] For example, when a load is applied due to an impact caused by vibration during transportation of the projector 1 or by accidentally dropping the projector 1, a particularly large load is generated around the joint of the second frame 22 with the first frame 21 that supports the optical member 20. In contrast, the pixel shift device 10 of the present embodiment can suppress deformation or damage of the second frame 22 by increasing the strength of the joint of the second frame 22 with the first frame 21 by using the pair of first oscillation shaft forming parts 24 as described above. Therefore, the pixel shift device 10 of the present embodiment has high reliability with improved resistance to impact loads.

[0061] The base connecting member 28 is a member that connects the second frame 22 and the base 23 on the second oscillation axis J2. The base connecting member 28 has a base fixing portion 28a, a first connecting shaft portion 28b, and a frame fixing portion 28c. The base connecting member 28 is fixed to the base 23 and the second frame 22 via screw members 223.

[0062] The frame fixing portion 28c fixes the base connecting member 28 to an upper end portion located on the upper side (+Z) in the vertical direction Z of the second frame 22. The base fixing portion 28a fixes the base connecting member 28 to the first second frame fixing portion 231 of the base 23. The first connecting shaft portion 28b connects between the frame fixing portion 28c and the base fixing portion 28a, and causes the second frame 22 to swing relative to the base 23 around the second swing axis J2. The base connecting member 28 may be formed integrally with the second frame 22.

[0063] Each of the pair of first actuators 25 generates a driving force between the first frame 21 and the second frame 22 to swing the first frame 21 relative to the second frame 22 . Each of the pair of first actuators 25 has a first magnet 25a arranged on the first frame 21, which is disposed on a second oscillation axis J2 perpendicular to the first oscillation axis J1, and a first coil 25b arranged on the base 23 and facing the first magnet 25a.

[0064] The pair of first actuators 25 are disposed symmetrically on both sides in the vertical direction Z with respect to the first oscillation axis J1 as the center with respect to the optical member 20 held by the first frame 21. Since the pair of first actuators 25 are positioned at an equal distance from the first oscillation axis J1, each of the driving forces can be transmitted in a well-balanced manner to the first frame 21 holding the optical member 20. Therefore, the pixel shift device 10 of this embodiment can rotate the first frame 21 around the first oscillation axis J1 without bias by the pair of first actuators 25.

[0065] The first magnet 25a is disposed on the first frame 21 via a magnet holding plate 27. Specifically, the first magnet 25a is disposed on the outer surface 21a of the first frame 21. Second Swing axis J2 The magnet is placed in a first magnet holder 21b provided in a position above the magnet. The magnet holding plate 27 is made of a metal such as iron and functions as a back yoke. The magnets used for the first magnet 25a include neodymium magnets and other magnets. Any permanent magnet with a certain magnetic force is acceptable. Samarium cobalt magnets, ferromagnets, etc. The magnet may be a ferrite magnet or an alnico magnet.

[0066] The first coil 25b is disposed on the inner surface 22a of the second frame 22 via a coil holder material 36. The coil holder material 36 is fixed to the base 23, and the first coil 25b and the first magnet 25a are disposed facing each other with a gap therebetween. The coil holder material 36 is made of a metal such as iron, and functions as a back yoke. The first coil 25b is formed of a coil wire wound around the coil holder material 36.

[0067] In addition, the positions of the first magnet 25a and the first coil 25b may be swapped, with the first magnet 25a being placed in a magnet holder extending from the base 23 and the first coil 25b being placed in a coil holder material provided on the outer surface 21a of the first frame 21.

[0068] Each of the pair of second actuators 26 is a device that is disposed between the second frame 22 and the base 23 and swings the second frame 22 relative to the base 23 . Similar to the first actuator 25, the pair of second actuators 26 are desirably arranged symmetrically on both sides in the left-right direction X about the second oscillation axis J2 with respect to the optical member 20 held by the second frame 22 via the first frame 21, thereby improving the transmission efficiency of each driving force. In other words, it is desirably to arrange the pair of second actuators 26 on the first oscillation axis J1.

[0069] Here, the pixel shift device 10 and the image generating unit in the projector 1 of this embodiment This section explains the positional relationship with 4. FIG. 5 is a diagram showing the positional relationship between the pixel shifting device 10 and the image generating unit 4. teeth XY plane FIG. As shown in FIG. 5, the image generating unit 4 includes light modulation devices 4R, 4G, and 4B and a light combining element 5. They are held together via frame member F to form a unit. In the projector 1 of the present embodiment, the light modulation device 4 R, 4B are brought into close proximity to the pixel shifting device 10. In the image generating unit 4 of this embodiment, the width of the light modulation devices 4R, 4G, and 4B is the same as that of the light combining element 5. It is larger than its width. In the pixel shift device 10 of this embodiment, the light modulation device 4G and the projection optical system 6 are arranged In the front-rear direction Y, the light modulation device 4R and the light modulation device 4B are located on the projection optical system 6 side. The front ends 4R1 and 4B1 overlap the pixel shift device 10. The front ends 4R1, 4B1 of the optical modulator 4B and the pixel shift device 10 are closely connected to each other. More specifically, the front ends 4R1 and 4B1 of the optical modulators 4R and 4B are adjacent to each other. Adjacent to the first frame 21, the second frame 22 and the base 23 of the element shift device 10 They are arranged in such a way that

[0070] In the pixel shift device 10 of this embodiment, the strength of the second frame 22 is increased by providing the first oscillation shaft forming portion 24, so that even if the second frame 22 is increased in size, it is not necessary to increase the thickness in order to improve the strength. In this manner, in the pixel shift device 10 of this embodiment, the thickness of the second frame 22 can be reduced, so that the front ends 4R1, 4B1 of the optical modulation devices 4R, 4B and the pixel shift device 10 can be disposed close to each other in the front-rear direction Y, thereby achieving a reduction in the size of the device configuration.

[0071] On the other hand, in the projector 1 of this embodiment, the front end portions 4R1, 4B1 of the light modulation devices 4R, 4B are positioned close to the second frame 22 and the base 23 of the pixel shifting device 10, making it difficult to position the second actuator on the first oscillation axis J1.

[0072] Therefore, in the pixel shift device 10 of this embodiment, a pair of second actuators 26 are held by actuator holders 29 provided on one side (-Z) in the vertical direction Z along the second oscillation axis J2 with respect to the first oscillation axis J1. The actuator holders 29 are provided so as to form pairs with the second actuators 26.

[0073] The pair of actuator holding parts 29 are located on the lower side (-Z) opposite the first oscillation axis J1 with respect to the first actuator 25. In the case of this embodiment, the pair of second actuators 26 are disposed further below (-Z) than the first actuator 25, which is located on the lower side (-Z) of the optical member 20.

[0074] The pair of actuator holding portions 29 are provided in regions of the second frame 22 and the base 23 that extend downward (-Z) in the up-down direction Z. The pair of actuator holding portions 29 are composed of a pair of second magnet holders 35 of a frame reinforcing member 30 described below and a pair of second coil holders 234 of the base 23.

[0075] Each second actuator 26 has a magnet and a coil arranged at a predetermined interval in the direction along the first oscillation axis J1. Specifically, each second actuator 26 has, in the direction along the first oscillation axis J1 intersecting the second oscillation axis J2, a second magnet 26a arranged in a second magnet holder 35 of the second frame 22 constituting the actuator holding part 29, and a second coil 26b arranged in a second coil holder 234 of the base 23 constituting the actuator holding part 29 and facing the second magnet 26a.

[0076] The second magnet 26a is disposed in the second magnet holder 35 via a magnet holding plate 27 which functions as a back yoke. The second coil holder 234 which holds the second coil 26b functions as a back yoke. The second magnet 26a and the second coil 26b have the same configuration as the first magnet 25a and the first coil 25b that constitute the first actuator 25, and therefore a description thereof will be omitted.

[0077] The positions of the second magnet 26a and the second coil 26b may be interchanged, with the second magnet 26a being disposed on the base 23 side and the second coil 26b being disposed on the second frame 22 side.

[0078] As described above, in the pixel shift device 10 of this embodiment, the second actuator 26 is provided in an area on the side of the second frame 22 where the first actuator 25 is disposed. More specifically, the pixel shift device 10 of this embodiment employs a structure in which the first actuator 25 and the second actuator 26 are collectively disposed on the lower side (-Z) of the optical member 20 in the up-down direction Z along the second oscillation axis J2.

[0079] According to the projector 1 of the present embodiment, by consolidating the second actuators 26 on one side of the first actuator 25, it is possible to arrange the pixel shift device 10 in a state in close proximity to the image generation unit 4 in the front-rear direction Y. For this reason, the projector 1 of the present embodiment can be made compact in the dimension in the front-rear direction Y. In addition, the pixel shift device 10 can efficiently capture the image light LT emitted from the projection optical system 6 of the image generation unit 4, and the light utilization efficiency of the image light LT can be improved.

[0080] On the other hand, in the pixel shift device 10 of this embodiment, as described above, it is necessary to place the second actuator 26 below (-Z) the first actuator 25. For this reason, the second frame 22 of this embodiment has an extension portion 220 that extends on the opposite side of the first oscillation axis J1 with respect to the first actuator 25 and on one axial side (-Z) along the second oscillation axis J2, as shown in Figs. 3 and 6, and holds a magnet, which is a component of the second actuator 26, via a frame reinforcing member 30 fixed to the extension portion 220.

[0081] As described above, in the pixel shift device 10 of this embodiment, the distance from the second actuator 26 to the optical member 20 is greater than the distance from the first actuator 25 to the optical member 20, so that the driving force of the second actuator 26 is less likely to be transmitted to the optical member 20.

[0082] In contrast, in the pixel shift device 10 of this embodiment, the driving force of the second actuator 26 is efficiently transmitted to the optical member 20 side, thereby allowing the second frame 22 to easily oscillate, so that the second frame 22 is made of a lightweight material such as aluminum.

[0083] Generally, lightweight materials such as aluminum have low rigidity, so that the second frame 22 made of a lightweight material may suffer from reduced durability or deformation due to the concentration of stress generated by the driving forces of the first actuator 25 and the second actuator 26. In particular, in the projector 1 of the present embodiment, in order to display bright images as described above, large panels are used as the liquid crystal panels 4RP, 4GP, and 4BP of the light modulation devices 4R, 4G, and 4B, which increases the size of the optical member 20, and as a result, the sizes of the first frame 21 and the second frame 22 also increase. If such a large second frame 22 is made of the above-mentioned lightweight member, there is a concern that the risk of the above-mentioned deterioration in durability and deformation may further increase.

[0084] In the pixel shift device 10 of this embodiment, the rigidity of the second frame 22 is increased by providing a frame reinforcing member 30 in a region on the side where the first actuator 25 and the second actuator 26 are collectively arranged in the second frame 22, specifically, in the extension portion 220. The frame reinforcing member 30 and the peripheral configuration of the second frame 22 on which the frame reinforcing member 30 is provided will be described below.

[0085] FIG. 6 is a perspective view showing the configuration of a main part of the second frame 22 on which the frame reinforcing member 30 is provided. 6, the frame reinforcing member 30 is made of, for example, austenitic stainless steel sheet metal and has a predetermined rigidity. The frame reinforcing member 30 may be made of a single plate material or may be divided into two plate materials as long as the purpose of sufficiently increasing the rigidity of the second frame 22 can be achieved.

[0086] The frame reinforcing member 30 is fixed to an extension portion 220 located on the lower side (-Z) of the second frame 22 in the up-down direction Z via a screw member 223. The frame reinforcing member 30 includes a main body portion 31 having a substantially U-shaped shape in a plan view, a second magnet holder 35 that holds a magnet of the second actuator 26 described below, and a base connecting portion 34 that is connected to a second second frame fixing portion 232 of the base 23.

[0087] The main body 31 of the frame reinforcement member 30 has a first surface 31a in contact with the surface 22b of the second frame 22 and a second surface 31b opposite to the first surface 31a. The main body 31 of the frame reinforcement member 30 includes a first wall portion 32 extending in the left-right direction X, and a pair of second wall portions 33 extending downward (-Z) in the up-down direction Z from both ends of the first wall portion 32.

[0088] In this embodiment, the first wall portion 32 is provided with a pair of pin holes 32a into which a pair of pins 22P provided on the surface 22b of the second frame 22 are inserted. By forming one of the pair of pin holes 32a as an elongated hole, it is possible to improve the workability when positioning the frame reinforcing member 30 and the second frame 22, regardless of the dimensional variation between the pair of pins 22P.

[0089] The second magnet holder 35 is a portion of the second surface 31b of the main body 31 that rises from the end portion 33a of each second wall portion 33 toward the rear side (-Y) in the front-rear direction Y and extends in the up-down direction Z. In the case of this embodiment, a portion of the second magnet holder 35 protrudes downward (-Z) in the up-down direction Z with respect to the second wall portion 33. In other words, the length of the second magnet holder 35 in the front-rear direction Y is longer than the length of the second wall portion 33 in the front-rear direction Y. Therefore, the second magnet holder 35 of the frame reinforcing member 30 is capable of holding a larger magnet. In this embodiment, the second magnet holder 35 corresponds to the "rising wall portion."

[0090] The second magnet holder 35 has a support plate 35a that supports a magnet and a locking claw 35b that locks the magnet supported by the support plate 35a, and is capable of stably holding the magnet. In the present embodiment, by providing the second magnet holder 35 as the rising wall portion, it is possible to improve the strength without increasing the size of the frame reinforcing member 30. In addition, by using the rising wall portion as a magnet holder, it is possible to prevent the frame reinforcing member from becoming large.

[0091] The base connecting portion 34 includes a base fixing portion 34a and a second connecting shaft portion 34b. The base fixing portion 34a is a portion that fixes the frame reinforcing member 30 to the second frame fixing portion 232 of the base 23. The second frame fixing portion 232 has a support surface 232a that supports the base fixing portion 34a, and a positioning pin 232b that protrudes from the support surface 232a. The second connecting shaft portion 34b is located on the second swing axis J2 and swingably connects the second frame 22 to the base 23 on the lower side (-Z) in the up-down direction Z. In this embodiment, the second connecting shaft portion 34b corresponds to the "connecting shaft portion." In the present embodiment, since the frame reinforcing member 30 includes the second connecting shaft portion 34b, it is possible to reduce the number of parts. Furthermore, by forming the second connecting shaft portion 34b with the frame reinforcing member 30, it is possible to improve the durability of the second connecting shaft portion 34b.

[0092] In this embodiment, the base fixing portion 34a is provided with a notch 34a1 through which a positioning pin 232b provided on the support surface 232a of the second frame fixing portion 232 is inserted. The position of the frame reinforcing member 30 relative to the base 23 is regulated by inserting the positioning pin 232b into the notch 34a1 of the base fixing portion 34a.

[0093] In this manner, the pixel shift device 10 of the present embodiment can increase the rigidity of the second frame 22 by providing the frame reinforcing member 30 to the extension portion 220 where the first actuator 25 and the second actuator 26 of the second frame 22 are concentrated.

[0094] As a result, in the pixel shift device 10 of this embodiment, deformation of the second frame 22 that oscillates around the second oscillation axis J2 is suppressed, so that the posture of the optical member 20 held via the first frame 21 can be controlled with high precision. Furthermore, since the second frame 22 is unlikely to deform, for example, the second frame 22 or the optical member 20 held by the second frame 22 via the first frame 21 can be prevented from moving in the front-rear direction Y and coming into contact with the image generating unit 4. Therefore, the pixel shifting device 10 of the present embodiment can be disposed in a state in which the pixel shifting device 10 is close to the image generating unit 4 in the front-rear direction Y. Therefore, the projector 1 of the present embodiment can be made smaller in size in the front-rear direction Y. Therefore, the pixel shifting device 10 of the present embodiment efficiently captures the image light LT emitted from the projection optical system 6 of the image generating unit 4, and the light utilization efficiency of the image light LT can be improved.

[0095] In addition, because deformation of the second frame 22 is unlikely to occur, the driving force of the second actuator 26 can be efficiently used to rotate the second frame 22. Therefore, the current supplied to the second actuator 26 to tilt the optical member 20 by the same angle is reduced, and the power consumption of the second actuator 26 can be reduced.

[0096] Next, the operation of the pixel shifting device 10 of the present embodiment will be described. In the pixel shift device 10 of this embodiment, in each first actuator 25, a magnetic field is generated by energizing the first coil 25b using a circuit board (not shown), and the magnetic field repels or attracts the first magnet 25a, thereby generating a force between the first magnet 25a and the first coil 25b in a direction intersecting the first oscillation axis J1. This causes the first frame 21 to oscillate around the first oscillation axis J1. As described above, the first frame 21 is connected to the second frame 22 by the connecting shaft parts 240 of the pair of first oscillation shaft forming parts 24 located at both ends in the direction along the first oscillation axis J1, so that the optical member 20 fixed to the first frame 21 can oscillate around the first oscillation axis J1 relative to the second frame 22.

[0097] In addition, in the pixel shift device 10 of this embodiment, in each second actuator 26, a magnetic field is generated by passing electricity through the second coil 26b using a circuit board (not shown), and the magnetic field repels or attracts the second magnet 26a, thereby generating a force between the second magnet 26a and the second coil 26b in a direction intersecting the second oscillation axis J2. As a result, the second frame 22 oscillates around the second oscillation axis J2. As described above, the first connecting shaft portion 28b and the second connecting shaft portion 34b located at both ends in the direction along the second oscillation axis J2 of the second frame 22 are connected to the base 23, so that the optical member 20 fixed to the second frame 22 via the first frame 21 and the first oscillation axis forming portion 24 can oscillate around the second oscillation axis J2 relative to the base 23.

[0098] In this manner, the pixel shifting device 10 of the present embodiment can control the attitude of the optical member 20 in two axes by utilizing the driving forces of the pair of first actuators 25 and the pair of second actuators 26. The pixel shifting device 10 can shift the optical path of the image light LT emitted from the image generating unit 4 in directions along two axes by changing the attitude of the optical member 20.

[0099] In this embodiment, when the first frame 21 swings around the first swing axis J1, the incident angle of the image light LT to the optical member 20 changes, and the optical path of the image light LT moves in the second direction F2 (see FIG. 2). Also, when the second frame 22 holding the first frame 21 swings around the second swing axis J2, the incident angle of the image light LT to the optical member 20 changes in a direction different from when swinging around the first swing axis J1, and the optical path of the image light LT moves in the first direction F1 (see FIG. 2).

[0100] As described above, the pixel shift device 10 of the present embodiment includes an optical member 20, a first frame 21 that holds the optical member 20 and oscillates around a first oscillation axis J1, a second frame 22 that is arranged around the first frame 21 and connected to the first frame 21 and oscillates around a second oscillation axis J2 perpendicular to the first oscillation axis J1, a base 23 that is arranged around the second frame 22 and connected to the second frame 22, a first actuator 25 that oscillates the first frame 21 relative to the second frame 22 between the first frame 21 and the second frame 22, a second actuator 26 that is provided in an area of ​​the second frame 22 on the side where the first actuator 25 is provided and that oscillates the second frame 22 relative to the base 23, and a frame reinforcing member 30 that is provided in an area of ​​the second frame 22 on the side where the first actuator 25 and the second actuator 26 are provided and has a first surface 31a that contacts a surface 22b of the second frame 22.

[0101] In the pixel shift device 10 of this embodiment, the first actuator 25 and the second actuator 26 are concentrated on one side of the second frame 22 with respect to the first oscillation axis J1, and stress generated by the driving forces of the first actuator 25 and the second actuator 26 is likely to concentrate on the second frame 22. In contrast, in the pixel shift device 10 of this embodiment, the frame reinforcing member 30 increases the rigidity to suppress deformation of the second frame 22, so that the attitude of the optical member 20 held via the first frame 21 can be controlled with high precision. Furthermore, because deformation of the second frame 22 is unlikely to occur, for example, it is possible to prevent the second frame 22 or the optical member 20 held by the second frame 22 via the first frame 21 from moving in the front-rear direction Y and coming into contact with the image generating unit 4. Therefore, the pixel shifting device 10 of the present embodiment can be disposed in a state in which the pixel shifting device 10 is close to the image generating unit 4 in the front-rear direction Y. Therefore, the dimension of the projector 1 of the present embodiment in the front-rear direction Y can be reduced.

[0102] Furthermore, in the pixel shift device 10 of this embodiment, the amount of distortion due to stress of the second frame 22 is reduced by increasing the rigidity with the frame reinforcing member 30, and the attenuation of the vibration of the second actuator 26 is suppressed, so that the second frame 22 can be efficiently swung. Therefore, the driving force of the second actuator 26 can be efficiently used to rotate the second frame 22, so that the second actuator 26 can be driven with less energy.

[0103] Furthermore, according to the pixel shift device 10 of this embodiment, the pair of beams 241 of the pair of first oscillation shaft forming parts 24 connecting the first frame 21 and the second frame 22 are formed along the surface 22b of the second frame 22, thereby increasing the strength of the second frame 22. Therefore, in the pixel shift device 10 of this embodiment, even when a load is applied due to vibration during transportation or an impact caused by a drop, the pair of first oscillation shaft forming parts 24 increase the strength of the connecting part of the second frame 22 with the first frame 21, thereby suppressing deformation or damage of the second frame 22. Therefore, even when a large and lightweight member is used as the second frame 22 by increasing the size of the optical member 20 of the pixel shift device 10, it is possible to impart resistance to impact loads by increasing the strength of the second frame 22. Therefore, according to the pixel shift device 10 of the present embodiment, even when a structure is adopted in which the first actuator 25 and the second actuator 26 are concentrated on one side of the large and lightweight second frame 22, it is possible to provide a highly reliable device in which the second frame 22 is resistant to impact loads.

[0104] According to the projector 1 of the present embodiment, since the pixel shifting device 10 capable of driving the second frame 22 with reduced energy is provided, the power consumption of the projector can be kept small.

[0105] Furthermore, since the projector 1 of this embodiment includes the pixel shift device 10, it has excellent resistance to loads caused by vibrations during transportation or impacts caused by dropping. Furthermore, since a large-sized optical member 20 can be adopted for the pixel shift device 10, large panels can be used for the liquid crystal panels 4RP, 4GP, and 4BP, and bright images can be projected onto the screen SCR.

[0106] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. Furthermore, the specific configurations of the various components constituting the light source device, such as the number, arrangement, shape, and materials, are not limited to those in the above embodiment and can be modified as appropriate.

[0107] Although the pixel shift device 10 in the above embodiment has a pair of the first actuator 25 and the second actuator 26, a configuration having one each of the first actuator 25 and the second actuator 26 may be adopted.

[0108] FIG. 7 shows a modified example of a pixel shift device. Enlarged view showing the main components In addition, in this modified example, In this embodiment, the same reference numerals are used for the same components as those in the above embodiment, and detailed description thereof is omitted. do.

[0109] For example, in the pixel shifting device 10 of the above embodiment, the frame reinforcing member 30 includes the second magnet holder 35, but the magnet holder may be configured as part of the second frame 22 rather than being integrated with the frame reinforcing member.

[0110] As shown in Figure 7, In the pixel shift device 10A of the modified example, the second actuator The second magnet holder 222 that holds the second magnet 26a of the first magnet 26 is a frame reinforcement. It is a separate member from the member 30A and is formed integrally with the second frame 22.

[0111] The frame reinforcing member 30A extends in a direction intersecting with a pair of second magnet holders 222 provided on the second frame 22 and includes a rib 130 disposed between the pair of second magnet holders 222. The rib 130 is a portion that rises from the second surface 31b of the main body portion 31 toward the rear side (-Y) in the front-rear direction Y and extends in the left-right direction X. In this modification, the rib 130 corresponds to the "rising wall portion."

[0112] The ribs 130 of the frame reinforcing member 30A can suppress deformation so that the pair of second magnet holders 222 of the second frame 22 approach each other in the left-right direction X. In other words, by providing the frame reinforcing member 30A of this modification with the ribs 130, the rigidity of the second frame 22 having the second magnet holders 222 can be increased.

[0113] Furthermore, a rib may be provided that extends in a direction intersecting the pair of second magnet holders 35 provided on the frame reinforcing member 30 of the pixel shift device 10 of the above embodiment. This further increases the rigidity of the frame reinforcing member 30, thereby suppressing deformation of the pair of second magnet holders 35 so that they approach each other in the left-right direction X.

[0114] Furthermore, the frame reinforcing member 30 in the above embodiment is provided integrally with the base connecting portion 34 including the second connecting shaft portion 34b. That is, the frame reinforcing member 30 in the above embodiment employs a configuration in which the base connecting portion that connects the second frame 22 and the base 23 is integral, but the frame reinforcing member may employ a configuration in which the connecting shaft portion is a separate member.

[0115] The following is a summary of this disclosure. (Appendix 1) An optical member; a first frame that holds an optical member and swings around a first swing axis; a second frame disposed around the first frame and connected to the first frame, the second frame swinging about a second swing axis perpendicular to the first swing axis; a base disposed around the second frame and coupled to the second frame; a first actuator between the first frame and the second frame for swinging the first frame relative to the second frame; a second actuator provided in a region of the second frame on a side where the first actuator is disposed, the second actuator causing the second frame to swing relative to the base; a frame reinforcing member provided in an area of ​​the second frame on which the first actuator and the second actuator are disposed, the frame reinforcing member having a first surface in contact with a surface of the second frame; Equipped with 13. A pixel shifting device comprising:

[0116] In a pixel shift device with this configuration, the first actuator and the second actuator are concentrated on one side of the second frame with respect to the first oscillation axis, and stress generated by the driving force of the first actuator and the second actuator is likely to concentrate on the second frame. In contrast, in a pixel shift device with this configuration, the frame reinforcing member increases the rigidity, suppressing deformation of the second frame, and therefore the attitude of the optical member held via the first frame can be precisely controlled. In addition, since the second frame is less likely to deform, for example, the second frame or the optical member held by the second frame via the first frame can be prevented from moving and coming into contact with the image generating unit. Therefore, the pixel shift device can be disposed in close proximity to the image generating unit, thereby achieving miniaturization. In addition, by increasing the rigidity with the frame reinforcing member, the amount of distortion due to stress in the second frame is reduced, and the damping of vibration of the second actuator is suppressed, allowing the second frame to swing efficiently. Therefore, the driving force of the second actuator can be efficiently used to rotate the second frame, allowing the second actuator to be driven with less energy.

[0117] (Appendix 2) the second actuator includes a magnet and a coil; one of the magnet and the coil is disposed on the second frame side, the other of the magnet and the coil is disposed on the base side; 2. The pixel shifting device according to claim 1,

[0118] According to this configuration, the magnet and coil that constitute the second actuator can be disposed on either the second frame or the base.

[0119] (Appendix 3) The second actuator is composed of a pair of actuators arranged on either side of the second oscillation shaft. 3. The pixel shifting device according to claim 2,

[0120] According to this configuration, the pair of second actuators stably secures the swinging force around the second swing axis, thereby stabilizing the change in the attitude of the optical member, thereby enabling the optical path of the image light to be shifted with high precision. In addition, although the provision of the pair of second actuators increases stress, the frame reinforcing member ensures resistance to the stress.

[0121] (Appendix 4) The frame reinforcing member has a rising wall portion rising from a second surface opposite to the first surface. 4. The pixel shifting device according to claim 1,

[0122] According to this configuration, the strength can be improved by providing the rising wall portion without increasing the size of the frame reinforcing member.

[0123] (Appendix 5) A portion of the second actuator is disposed on the rising wall portion of the frame reinforcing member. 5. The pixel shifting device according to claim 4,

[0124] According to this configuration, the components of the second actuator are held by utilizing the rising wall portion, so that an increase in size of the frame reinforcing member can be suppressed.

[0125] (Appendix 6) the second frame has an extension portion that extends on a side opposite to the first swing shaft with respect to the first actuator and on one axial side along the second swing shaft and is coupled to the base; The frame reinforcing member is fixed to the extension portion. 6. The pixel shifting device according to claim 1,

[0126] The second frame is easily deformed due to the extension extending to one side in the axial direction along the second oscillation shaft. In response to this, the frame reinforcing member is fixed to the extension of the second frame, and the extension, which is easily weakened, is efficiently reinforced, thereby effectively suppressing deformation of the second frame.

[0127] (Appendix 7) The frame reinforcing member is located on the second swing shaft and includes a connecting shaft portion that connects the second frame and the base. 7. The pixel shifting device according to claim 1,

[0128] According to this configuration, since the frame reinforcing member includes the connecting shaft, the number of parts can be reduced and the durability of the connecting shaft can be improved.

[0129] (Appendix 8) an image generating unit that generates image light; a projection optical system that projects the image light; and a pixel shifting device according to any one of Supplementary Note 1 to Supplementary Note 7, which is disposed between the image generating unit and the projection optical system and shifts an optical path of the image light from the image generating unit. A projector characterized by:

[0130] According to a projector having this configuration, since a pixel shift device that can drive the second frame with reduced energy is provided, the power consumption of the projector can be kept low. [Explanation of symbols]

[0131] 1...projector, 4...image generating section, 5...light combining element, 6...projection optical system, 10, 10A...pixel shifting device, 20...optical member, 21...first frame, 22...second frame, 22b...surface (surface of second frame), 23...base, 25...first actuator, 26...second actuator, 34b...second connecting shaft section (connecting shaft section), 35...second magnet holder (raised wall section), 130...rib (raised wall section), 220...extension section, J1...first oscillation shaft, J2...second oscillation shaft, LT...image light.

Claims

1. An optical member; a first frame that holds an optical member and swings about a first swing axis; a second frame disposed around the first frame and connected to the first frame, the second frame swinging about a second swing axis perpendicular to the first swing axis; a base disposed around the second frame and coupled to the second frame; a first actuator between the first frame and the second frame for swinging the first frame relative to the second frame; a second actuator provided in a region of the second frame on a side where the first actuator is disposed, the second actuator swinging the second frame relative to the base; a frame reinforcing member provided in an area of ​​the second frame on which the first actuator and the second actuator are disposed, the frame reinforcing member having a first surface in contact with a surface of the second frame, The frame reinforcing member has a rising wall portion rising from a second surface opposite to the first surface.

2. the second actuator includes a magnet and a coil; one of the magnet and the coil is disposed on the second frame side, The pixel shifting device according to claim 1 , wherein the other of the magnet and the coil is disposed on the base side.

3. The pixel shifting device according to claim 2 , wherein the second actuator is composed of a pair of actuators arranged on either side of the second oscillation axis.

4. The pixel shifting device according to claim 1 , wherein a portion of the second actuator is disposed on the rising wall of the frame reinforcing member.

5. the second frame has an extension portion that extends on a side opposite to the first swing shaft with respect to the first actuator and on one axial side along the second swing shaft and is coupled to the base; The pixel shifting device of claim 1 , wherein the frame reinforcing member is fixed to the extension.

6. The pixel shifting device according to claim 1 , wherein the frame reinforcing member is located on the second oscillation shaft and includes a connecting shaft portion that connects the second frame and the base.

7. an image generating unit that generates image light; a projection optical system that projects the image light; 4. A projector comprising: a pixel shifting device according to claim 1, which is disposed between the image generating section and the projection optical system and shifts an optical path of the image light from the image generating section.

Images