Shift device and projector

Abstract

The present invention provides a shift device and projector that can improve the accuracy of the movement of projection optical devices. [Solution] The shift device is a shift device that moves a projection optical device that projects an image in a first direction perpendicular to the optical axis of the projection optical device, and comprises a first moving member for moving the projection optical device, a frame having an opening through which the projection optical device is inserted and which movably supports the first moving member, a first drive unit that applies a first driving force to the first moving member to move the first moving member along the first direction, and a first guide unit that guides the movement of the first moving member along the first direction, wherein the first drive unit and the first guide unit are arranged on a virtual first straight line along the first direction, with the opening in between.

Description

Technical Field

[0001] The present disclosure relates to a shift device and a projector.

Background Art

[0002] Conventionally, a projector including a lens shift mechanism that supports a projection lens and moves the projection lens in two directions within a plane orthogonal to the optical axis of the projection lens has been known (see, for example, Patent Document 1). In the projector described in Patent Document 1, the lens shift mechanism includes a base portion, a first moving portion, a second moving portion, a first driving portion, a second driving portion, a first guiding mechanism, and a second guiding mechanism.

[0003] [[ID=仃]] The base portion is a member that supports the entire lens shift mechanism, and an opening through which a portion on the light incident side of the projection lens is inserted is formed at the center of the base portion. The first moving portion has a first moving main body portion disposed in front of the base portion. The second moving portion is disposed in front of the first moving portion and supports the projection lens. The first driving portion is provided on the base portion and moves the first moving portion in the left - right direction. The second driving portion is provided on the first moving portion and moves the second moving portion along the up - down direction.

[0004] The first guiding mechanism guides the movement of the first moving portion along the left - right direction with respect to the base portion, and the second guiding mechanism guides the movement of the second moving portion along the up - down direction. Each guiding mechanism has a slide guiding device. The slide guide device comprises a first guide member, a second guide member, and a plurality of rolling members, and the first guide member and the second guide member are configured to slide relative to each other along the longitudinal direction. In the slide guide device of the first guide mechanism, the second guide member is fixed to the base portion, and the first guide member is fixed to the first moving portion. In the slide guide device of the second guide mechanism, the second guide member is fixed to the first moving portion, and the first guide member is fixed to the second moving portion. With each guide mechanism equipped with such a slide guide device, the movement of the first moving portion can be defined as linear motion along the left-right direction, and the movement of the second moving portion can be defined as linear motion along the up-down direction. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2016-038532 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the slide guide device described in Patent Document 1 is not only relatively large in size, but its cost is also relatively high. As a result, the size of the lens shift mechanism equipped with the slide guide device tends to increase, and the cost of the lens shift mechanism tends to increase. In contrast, it is conceivable to construct a lens shift mechanism inexpensively by configuring a guide mechanism that guides the moving object using, for example, a guide pin and a guide groove into which the guide pin is inserted. However, depending on the positional relationship between such a guide mechanism and the drive unit that applies the driving force to the moving object, a moment that rotates the moving object may be generated when the driving force is applied to the moving object. In such a case, the moving object may move obliquely to the direction perpendicular to the optical axis of the projection lens, making it impossible to achieve accurate shifting of the projection lens. In this case, there is a problem in that the image quality projected by the projection lens deteriorates. Therefore, there has been a demand for a configuration that can improve the accuracy of the movement of the projection optical device. [Means for solving the problem]

[0007] A shift device according to a first aspect of the present disclosure is a shift device for moving a projection optical device that projects an image in a first direction perpendicular to the optical axis of the projection optical device, comprising: a first moving member for moving the projection optical device; a frame having an opening through which the projection optical device is inserted and which movably supports the first moving member; a first drive unit for applying a first driving force to the first moving member to move the first moving member along the first direction; and a first guide unit for guiding the movement of the first moving member along the first direction, wherein the first drive unit and the first guide unit are arranged on a virtual first straight line along the first direction, with the opening in between.

[0008] A projector according to a second aspect of the present disclosure comprises a light source, an optical modulator for modulating light emitted from the light source, a projection optical device for projecting the light modulated by the optical modulator, and a shift device according to the first aspect for moving the projection optical device. [Brief explanation of the drawing]

[0009] [Figure 1] A perspective view showing the external appearance of a projector in one embodiment. [Figure 2] A schematic diagram showing the configuration of an image projection device in one embodiment. [Figure 3] A perspective view showing a projection optical device and a shift device in one embodiment. [Figure 4] A perspective view showing a projection optical device and a shift device in one embodiment. [Figure 5] A perspective view showing a shift device in one embodiment. [Figure 6] A perspective view showing a shift device in one embodiment. [Figure 7] An exploded perspective view showing a shift device in one embodiment. [Figure 8]Exploded perspective view of a shift device in an embodiment. [Figure 9] Exploded perspective view of a frame, a first moving member, and a second moving member in an embodiment. [Figure 10] Exploded perspective view of a frame, a first moving member, and a second moving member in an embodiment. [Figure 11] View showing a frame in an embodiment. [Figure 12] View showing a first moving member in an embodiment. [Figure 13] View showing a first moving member in an embodiment. [Figure 14] View showing a second moving member in an embodiment. [Figure 15] Perspective view showing a first feed screw and a first meshing member in an embodiment. [Figure 16] Perspective view showing a first feed screw and a first meshing member in an embodiment. [Figure 17] Cross-sectional view showing a first feed screw and a first meshing member in an embodiment. [Figure 18] Cross-sectional view showing a shift device in an embodiment. [Figure 19] Cross-sectional view showing a frame and a first moving member in an embodiment. [Figure 20] Cross-sectional view showing a second feed screw and a second meshing member in an embodiment. [Figure 21] Cross-sectional view showing a shift device in an embodiment. [Figure 22] Cross-sectional view showing a shift device in an embodiment.

Mode for Carrying Out the Invention

[0010] Hereinafter, an embodiment of the present disclosure will be described based on the drawings. [Schematic Configuration of Projector] FIG. 1 is a perspective view showing the appearance of a projector 1 according to the present embodiment. The projector 1 according to this embodiment is a display device that modulates light emitted from a light source to form image light corresponding to an image signal and projects the formed image light onto a projection surface. As shown in Figure 1, the projector 1 includes an outer casing 2.

[0011] [Outer casing configuration] The outer casing 2 has a front section 21, a rear section 22, a top section 23, a bottom section 24, a right side section 25, and a left side section 26, and is formed in a substantially rectangular parallelepiped shape. The front section 21 has a projection port 211. The projection port 211 exposes a part of the projection optical device 36 of the image projection device 3, which will be described later. The top surface 23 exposes two dials D1 and D2 for operating the shift device 4, which will be described later. The bottom portion 24 is provided with a plurality of legs 241 that contact the mounting surface on which the projector 1 is installed.

[0012] [Configuration of the image projection device] Figure 2 is a schematic diagram showing the configuration of the image projection device 3. The projector 1 includes an image projection device 3 housed inside the outer casing 2. The image projection device 3 projects image light corresponding to the image signal. As shown in Figure 2, the image projection device 3 comprises a light source 30, a uniformizing device 31, a color separation device 32, a relay device 33, an image forming device 34, an optical component housing 35, a projection optical device 36, and a shift device 4.

[0013] The light source 30 emits light. Although not shown in the diagram, the light source 30 comprises a solid-state light-emitting element such as an LD (Laser Diode) and a wavelength conversion element that converts the wavelength of at least a portion of the light emitted from the solid-state light-emitting element. The light source 30 may also include a discharge light source lamp such as an ultra-high pressure mercury lamp. The uniformizing device 31 equalizes the illuminance distribution of the light emitted from the light source 30. The light with the equalized illuminance distribution passes through the color separation device 32 and the relay device 33 to illuminate the modulation region of the light modulation device 343 of the image forming apparatus 34, which will be described later. The uniformizing device 31 includes two lens arrays 311 and 312, a polarization conversion element 313, and a superimposed lens 314. The color separation device 32 separates the light incident from the uniformizing device 31 into red, green, and blue light. The color separation device 32 comprises two dichroic mirrors 321 and 322, and a reflective mirror 323 that reflects the blue light separated by the dichroic mirror 321.

[0014] The relay device 33 is installed in the optical path of the red light, which is longer than the optical paths of the other colored light, in order to suppress the loss of red light. The relay device 33 comprises an incident lens 331, a relay lens 333, and reflective mirrors 332 and 334. In this embodiment, the relay device 33 is installed on the optical path of the red light. However, this is not the only option; for example, the colored light with a longer optical path than the other colored light may be blue light, and the relay device 33 may be installed on the optical path of the blue light.

[0015] The image forming apparatus 34 forms image light from light incident from the color separation device 32 and the relay device 33. Specifically, the image forming apparatus 34 modulates the incident red, green, and blue light, and synthesizes the modulated light to form image light. The image forming apparatus 34 includes three field lenses 341, three incident polarizers 342, three light modulators 343, three field angle compensating plates 344, and three exit polarizers 345, which are provided according to the incident color light, and one color synthesis element 346. The optical modulator 343 modulates the incident light according to the image signal. That is, the optical modulator 343 modulates the light emitted from the light source 30. The optical modulator 343 includes an optical modulator 343R for red light, an optical modulator 343G for green light, and an optical modulator 343B for blue light. In this embodiment, the optical modulator 343 is made up of a transmissive liquid crystal panel, and the liquid crystal light bulb is made up of an incident polarizer 342, an optical modulator 343, and an exit polarizer 345. The color synthesis element 346 synthesizes the colored light modulated by the light modulators 343B, 343G, and 343R to form image light. In this embodiment, the color synthesis element 346 is composed of a cross dichroic prism, but it is not limited to this and can also be composed of, for example, multiple dichroic mirrors.

[0016] The optical component housing 35 houses the above-described devices 31 to 34 inside. The image projection device 3 has an illumination optical axis Ax, which is the optical axis in its design, and the optical component housing 35 holds the devices 31 to 34 at predetermined positions along the illumination optical axis Ax. The light source 30 and the projection optical device 36 are positioned at predetermined positions along the illumination optical axis Ax. The projection optical device 36 is a projection lens that magnifies and projects the image light formed by the image forming apparatus 34 onto the projection surface. In other words, the projection optical device 36 projects light modulated by the light modulation devices 343B, 343G, and 343R. The projection optical device 36 is configured as a lens assembly in which multiple lenses are housed within a cylindrical lens barrel 361, for example.

[0017] [Shift device configuration] Figure 3 is a perspective view showing the projection optical device 36 and shift device 4 as seen from the image light emission side, and Figure 4 is a perspective view showing the projection optical device 36 and shift device 4 as seen from the image light incidence side. Furthermore, Figures 5 and 6 are perspective views showing the shift device 4 with the projection optical device 36 omitted from the illustration. More specifically, Figure 5 is a perspective view showing the shift device 4 as seen from the image light emission side, and Figure 6 is a perspective view showing the shift device 4 as seen from the image light incidence side. The shift device 4 supports the lens barrel 361 of the projection optical device 36 and moves the projection optical device 36 in two directions perpendicular to the lens optical axis of the projection optical device 36. As shown in Figures 3 to 6, the shift device 4 comprises a frame 5, a first moving member 6, a second moving member 7, a drive device 8, a transmission device 9, and dials D1 and D2. In the following description, the three mutually orthogonal directions will be referred to as the +X direction, the +Y direction, and the +Z direction. In this embodiment, the +Z direction is the direction along the lens optical axis of the projection optical device 36. More specifically, the +Z direction is the direction along which the image light travels along the lens optical axis of the projection optical device 36. The +X direction is the rightward direction when viewing the shift device 4 from the light emission side, and the +Y direction is the upward direction when viewing the shift device 4 from the light emission side. That is, the +Z direction is the direction from the rear part 22 to the front part 21, the +X direction is the direction from the left side part 26 to the right side part 25, and the +Y direction is the direction from the bottom part 24 to the top part 23. Furthermore, the direction opposite to the +Z direction is defined as the -Z direction, the direction opposite to the +X direction is defined as the -X direction, and the direction opposite to the +Y direction is defined as the -Y direction. Therefore, "looking at the shift device 4 from the +Z direction" is synonymous with "looking at the shift device 4 from the image light emission side," and "looking at the shift device 4 from the -Z direction" is synonymous with "looking at the shift device 4 from the image light incidence side."

[0018] [Dial Configuration] As described above, dials D1 and D2 are exposed on the top surface 23 and accept rotational operation around a rotation axis along the +Y direction. That is, dials D1 and D2 are rotated by the user. Dials D1 and D2 are attached to the frame 5 by the first mounting member 911 of the transmission device 9, which will be described later. Dial D1 applies a rotational force to the drive unit 8 that shifts the projection optical device 36 along the +Y direction. Dial D2 applies a rotational force to the drive unit 8 that shifts the projection optical device 36 along the +X direction. Dial D2 is positioned in the -X direction relative to Dial D1.

[0019] [Configuration of the transmission device] Figures 7 and 8 are exploded perspective views of the shift device 4 with dials D1, D2 and transmission device 9 removed, viewed from the +Z direction. More specifically, Figure 7 is an exploded perspective view of the shift device 4 viewed from the +X and +Y directions, and Figure 8 is an exploded perspective view of the shift device 4 viewed from the -X and -Y directions. First, let's explain the configuration of the transmission device 9. The transmission device 9 transmits the rotation of dials D1 and D2 to the drive device 8. The transmission device 9 includes a mounting member 91, a first transmission unit 92, and a second transmission unit 93.

[0020] [Configuration of mounting components] The mounting member 91 supports the dials D1 and D2 and the first transmission unit 92 and the second transmission unit 93, and is attached to the frame 5 or the first moving member 6. The mounting member 91 includes a first mounting member 911, a second mounting member 912, and a third mounting member 913. In this embodiment, each of the mounting members 911 to 913 is made of sheet metal. The first mounting member 911 pivotally supports the dials D1 and D2 and the first gear 931 which constitutes the second transmission unit 93. The first mounting member 911 is fixed to a surface facing the +Y direction in a frame 5 which is substantially rectangular when viewed from the +Z direction. The second mounting member 912 pivotally supports the shaft gear 921 and gears 922-924 that constitute the first transmission unit 92, and the first lead screw 81 of the drive unit 8, which will be described later. That is, the second mounting member 912 has a pin-shaped support portion 9121 that rotatably supports the first lead screw 81 about a rotation axis along the +Y direction. The second mounting member 912 is fixed to the surface of the frame 5 facing the -Y direction. The third mounting member 913 supports the second gear 932 and the third gear 933 that constitute the second transmission unit 93, as well as the second lead screw 82 of the drive unit 8, which will be described later. Specifically, the third mounting member 913 has a pin-shaped support portion 9131 that rotatably supports the second lead screw 82 about a rotation axis along the +X direction. The third mounting member 913 is fixed to the surface of the first moving member 6 that faces the -X direction.

[0021] [Configuration of the first transmission unit] The first transmission unit 92 transmits the rotational force of the dial D1 to the first lead screw 81 of the drive unit 8, thereby rotating the first lead screw 81 in response to the user's rotational operation on the dial D1, and consequently shifting the projection optical device 36 along the +Y direction. The first transmission unit 92 includes a shaft gear 921, a first gear 922, a second gear 923, and a third gear 924. The shaft gear 921 and gears 922-924 are reduction gears rotatably supported by a second mounting member 912 around a rotation axis along the +Y direction. The shaft gear 921 is connected to the dial D1 and rotates integrally with the dial D1. The first gear 922 meshes with the shaft gear 921, the second gear 923 meshes with the first gear 922, and the third gear 924 meshes with the second gear 923 and the first lead screw 81. In this way, the rotational force of dial D1 is transmitted to the first lead screw 81 via shaft gear 921 and gears 922-924. As a result, the first lead screw 81 rotates around a rotation axis along the +Y direction.

[0022] [Configuration of the second transmission unit] The second transmission unit 93 transmits the rotational force of the dial D2 to the second lead screw 82 of the drive unit 8, causing the second lead screw 82 to rotate in response to the user's rotational operation on the dial D2, thereby shifting the second moving member 7 and the projection optical device 36 along the +X direction. The second transmission unit 93 includes a first gear 931 pivotally supported on the first mounting member 911, and second gears 932 and third gears 933 pivotally supported on the third mounting member 913. Gears 931 to 933 constitute a reduction gear.

[0023] The first gear 931 is mounted on the surface of the first mounting member 911 facing the -Y direction, so as to be rotatable about a rotation axis along the +Y direction. As shown in Figure 8, the first gear 931 meshes with a gear portion D21 provided at the -Y end of the dial D2, and rotates in conjunction with the rotation of the dial D2. The second gear 932 is mounted on the third mounting member 913 so as to be rotatable about a rotation axis along the +Y direction. The second gear 932 meshes with the first gear 931 and the third gear 933, respectively. More specifically, the second gear 932 is a two-stage gear having two meshing portions 9321 and 9322, where meshing portion 9321 meshes with the first gear 931 and meshing portion 9322 meshes with the third gear 933. The third gear 933 is mounted on the third mounting member 913 on a surface facing the +X direction, so as to be rotatable about a rotation axis along the +X direction. The third gear 933 meshes with the second gear 932 and the second lead screw 82, respectively, and rotates the second lead screw 82 by the rotational force transmitted from the second gear 932. The third gear 933 is a two-stage gear having two meshing parts 9331 and 9332. Meshing part 9331 meshes with the meshing part 9322 of the second gear 932, and meshing part 9332 meshes with the second lead screw 82. In this way, the second gear 932 and the third gear 933 constitute a bevel gear that converts the rotation axis.

[0024] [Frame structure] Figures 9 and 10 are exploded perspective views showing the frame 5, the first moving member 6, and the second moving member 7. Of these, Figure 9 is an exploded perspective view showing the frame 5 etc. as seen from the +Z direction, and Figure 10 is an exploded perspective view showing the frame 5 etc. as seen from the -Z direction. For the sake of explanation, the transmission device 9 and dials D1 and D2 are omitted from the illustration in Figures 9 and 10. Frame 5 supports the first moving member 6, the second moving member 7, the drive unit 8, the transmission unit 9, and the dials D1 and D2. Frame 5 is rectangular in shape when viewed from the +Z direction, and at least a portion of frame 5 overlaps with the first moving member 6 and the second moving member 7 when viewed from the +Z direction. As shown in Figures 9 and 10, frame 5 is connected to the second movable member 7 by a connecting member CM, which will be described later, and the first movable member 6 is sandwiched between it and the second movable member 7.

[0025] Figure 11 shows frame 5 as viewed from the +Z direction. As shown in Figures 9 to 11, frame 5 has an opening 51 in its approximate central portion through which the lens barrel 361 of the projection optical device 36 is inserted along the +Z direction. In addition, as shown in Figures 9 and 11, frame 5 has a first guide groove 52, a first guide recess 53, a protrusion 54, and a through-hole 55 provided on the first surface 5A facing the +Z direction.

[0026] As shown in Figure 11, the first guide groove 52 is located in the +Y direction relative to the opening 51 and extends along the +Y direction. Together with the first guide pin 63, which will be described later, of the first movable member 6 inserted into the first guide groove 52, the first guide groove 52 constitutes the first guide portion GD1 that guides the movement of the first movable member 6 along the +Y direction. The first guide groove 52 is formed in a substantially U-shape facing the -Y direction when viewed from the +Z direction. As shown in Figure 11, the first guide groove 52 has a first inner surface 521 facing the +X direction, a second inner surface 522 facing the -X direction, and a third inner surface 523 facing the -Y direction.

[0027] The first inner surface 521 and the second inner surface 522 guide the movement of the first guide pin 63, which is inserted into the first guide groove 52 from the +Z direction, along the +Y direction, and consequently guide the movement of the first moving member 6 along the +Y direction. The third inner surface 523 connects the +Y direction end of the first inner surface 521 and the +Y direction end of the second inner surface 522. Alternatively, instead of the through-hole 55 described later, the third inner surface 523 may define the +Y direction end of the first movable member 6. In this case, the movement of the first movable member 6 in the +Y direction may be restricted by the first guide pin 63 contacting the third inner surface 523.

[0028] The first guide recess 53 is located in the -Y direction relative to the opening 51 and extends along the +Y direction. That is, the first guide recess 53 is located on the opposite side of the opening 51 from the first guide groove 52. The first guide recess 53 has a first inner surface 531 facing the +X direction, a second inner surface 532 facing the -X direction, and a third inner surface 533 facing the -Y direction. The first guide recess 53 is recessed in the -Z direction to avoid the first meshing member SM1 and the first lead screw 81, and is also a recess that guides the movement of the first movable member 6, to which the first meshing member SM1 is fixed, along the +Y direction. More specifically, a part of the first movable member 6 is positioned between the first inner surface 531 and the second inner surface 532, and each inner surface 531, 532 guides the movement of the first movable member 6 along the +Y direction. At the bottom of the first guide recess 53, a support portion 534 is erected in the +Z direction in the portion corresponding to the periphery of the opening 51. The support portion 534 rotatably supports the +Y direction end of the first lead screw 81 about a rotation axis along the +Y direction.

[0029] As shown in Figures 9 and 11, the protrusions 54 are provided projecting in the +Z direction from each of the four corners of the rectangular first surface 5A. That is, the frame 5 has four protrusions 54. The surface 54A facing the +Z direction in each protrusion 54 is a sliding surface on which the first movable member 6 slides, and is a restricting surface that restricts the rotation of the first movable member 6 about a rotation axis along the +Y direction. The rotation of the first movable member 6 about a rotation axis along the +Y direction is also restricted by the sliding surface on the second movable member 7 on which the first movable member 6 slides. The through-hole 55 is provided on the surface 54A of each protrusion 54 and penetrates the protrusion 54 along the +Z direction. The insertion pin 73 of the second movable member 7, described later, is inserted through the through-hole 55 in the -Z direction. The inner edge of the through-hole 55 defines the movable end of the first movable member 6 along the +Y direction. That is, when the first movable member 6 moves relative to the frame 5 in the +Y direction, the insertion pin 73 of the second movable member 7, which moves integrally with the first movable member 6 in the +Y direction, contacts the portion of the inner edge of the through-hole 55 in the +Y direction, thereby restricting the movement of the second movable member 7, and consequently the first movable member 6, in the +Y direction. Similarly, when the first movable member 6 moves relative to the frame 5 in the -Y direction, the insertion pin 73 of the second movable member 7, which moves integrally with the first movable member 6 in the -Y direction, contacts the portion in the -Y direction at the inner edge of the through-hole 55, thereby restricting the movement of the second movable member 7, and consequently the first movable member 6, in the -Y direction.

[0030] As shown in Figure 10, the frame 5 is oriented in the -Z direction and has a second surface 5B opposite to the first surface 5A. The frame 5 has a recess 56 provided on the second surface 5B and a connecting member 57 disposed within the recess 56. The recesses 56 are located at each of the four corners of the rectangular second surface 5B and are recessed in the +Z direction. In other words, the frame 5 has four recesses 56, and each recess 56 corresponds to a protrusion 54.

[0031] The connecting members 57 are positioned within each recess 56. The connecting members 57 are connected to insertion pins 73 that pass through the through-holes 55, maintaining the spacing between the frame 5, the first movable member 6, and the second movable member 7. The connecting members 57 comprise a plate 571, a screw pin 572, and a biasing member 573. The plate 571 is formed in a substantially rectangular shape that is elongated in the +X direction and is slidably positioned within the recess 56 along the +Y direction. The plate 571 has an elongated hole that is elongated in the +X direction, through which a screw pin 572 is inserted along the +Z direction. The screw pin 572 is inserted through the elongated hole and through-hole 55 of the plate 571 in the +Z direction and fixed to the insertion pin 73 of the second movable member 7. This connects the frame 5 and the second movable member 7 while the first movable member 6 is held in place. The biasing member 573 is interposed between the head of the screw pin 572 and the plate 571. In this embodiment, the biasing member 573 is composed of a compression coil spring and applies a biasing force to the head of the screw pin 572 and the plate 571 in a direction that moves them apart from each other. This biasing force causes the frame 5 and the first movable member 6 to be pressed towards the second movable member 7. Furthermore, this biasing force biases the head of the screw pin 572 away from the second movable member 7, causing the second movable member 7, to which the screw pin 572 is fixed, to be pulled towards the frame 5, thereby pressing the second movable member 7 against the frame 5.

[0032] [Configuration of the first movable member] The first movable member 6 is positioned in the +Z direction relative to the frame 5 and is supported by the frame 5 so as to be movable along the +Y direction. More specifically, the frame 5, the first movable member 6, and the second movable member 7 are positioned in the order of frame 5, first movable member 6, and second movable member 7 in the +Z direction, with the first movable member 6 positioned between frame 5 and second movable member 7 in the +Z direction. That is, the first movable member 6 is positioned in the -Z direction relative to the second movable member 7. As shown in Figures 9 and 10, the first movable member 6 is formed in a substantially rectangular shape when viewed from the ±Z direction. The first movable member 6 has an opening 61 through which a part of the lens barrel 361 of the projection optical device 36 is inserted along the +Z direction, and through-holes 62 provided at the four corners of the first movable member 6. In addition, the first movable member 6 has a first surface 6A facing the +Z direction and a second surface 6B facing the -Z direction. The through-hole 62 penetrates the first movable member 6 along the +Z direction. The insertion pin of the second movable member 7 is inserted through the through-hole 62 from the -Z direction. On the second surface 6B, the surface surrounding the through-hole 62 is in contact with the surface 54A of the projection 54 and is a sliding surface that slides along surface 54A when the first movable member 6 moves along the +Y direction. On the first surface 6A, the surface surrounding the through-hole 62 is in contact with the second movable member 7 and is a sliding surface on which the second movable member 7 slides when the second movable member 7 moves along the +X direction.

[0033] Figure 12 shows the first moving member 6 as viewed from the -Z direction. As shown in Figure 12, the first movable member 6 has a first guide pin 63 provided on the second surface 6B and a first placement portion 64 on which the first engaging member SM1 is positioned. The first guide pin 63 is provided in the portion of the opening 61 in the +Y direction and protrudes in the -Z direction. The first guide pin 63 is formed in a cylindrical shape when viewed from the -Z direction and is inserted into the first guide groove 52 of the frame 5 from the -Z direction when the frame 5 and the first movable member 6 are assembled. In other words, the first guide pin 63, together with the first guide groove 52, constitutes the first guide portion GD1 that guides the movement of the first movable member 6 along the +Y direction. The first placement section 64 is located on the opposite side of the opening 61 from the first guide pin 63. That is, the first placement section 64 is located in the -Y direction relative to the opening 61. The first engagement member SM1 is placed in the first placement section 64. The first engagement member SM1 is fixed to the first placement section 64 by a fixing member such as a screw. The first interlocking member SM1 will be described in detail later.

[0034] Figure 13 shows the first moving member 6 as viewed from the +Z direction. As shown in Figure 13, the first movable member 6 has a second guide groove 65 and a second guide recess 66 provided on the first surface 6A. The second guide groove 65 is located in the +X direction relative to the opening 61 and extends along the +X direction. Together with the second guide pin 74 of the second movable member 7, which is inserted into the second guide groove 65 (described later), the second guide groove 65 constitutes the second guide portion GD2 that guides the movement of the second movable member 7 along the +X direction. The second guide groove 65 is formed in an elongated oval shape that is long in the +X direction when viewed from the +Z direction. The second guide groove 65 has a first inner surface 651 facing the +Y direction, a second inner surface 652 facing the -Y direction, a third inner surface 653 facing the -X direction, and a fourth inner surface 654 facing the +X direction.

[0035] The first inner surface 651 and the second inner surface 652 guide the movement of the second guide pin 74, which is inserted into the second guide groove 65 from the +Z direction, along the +X direction, and consequently guide the movement of the second moving member 7 along the +X direction. The third inner surface 653 and the fourth inner surface 654 are contact surfaces that the second guide pin 74 can contact. The third inner surface 653 restricts the movement of the second guide pin 74 in the +X direction by contacting it when the second guide pin 74 moves in the +X direction, and consequently restricts the movement of the second movable member 7 in the +X direction. The fourth inner surface 654 restricts the movement of the second guide pin 74 in the -X direction by contacting it when the second guide pin 74 moves in the -X direction, and consequently restricts the movement of the second movable member 7 in the -X direction. In other words, the third inner surface 653 and the fourth inner surface 654 define the movable ends of the second movable member 7 in the range of movement along the +X direction.

[0036] The second guide recess 66 is located in the -X direction relative to the opening 61 and extends along the +X direction. That is, the second guide recess 66 is located on the opposite side of the opening 61 from the second guide groove 65. The second guide recess 66 has a first inner surface 661 facing the +Y direction, a second inner surface 662 facing the -Y direction, and a third inner surface 663 facing the -X direction. The second guide recess 66 avoids the second meshing member SM2 and the second lead screw 82, and also guides the movement of the second movable member 7, to which the second meshing member SM2 is fixed, along the +X direction. More specifically, a part of the second movable member 7 is positioned between the first inner surface 661 and the second inner surface 662, and each inner surface 661, 662 guides the movement of the second movable member 7 along the +X direction. At the bottom of the second guide recess 66, a support portion 664 is erected in the +Z direction in the portion corresponding to the periphery of the opening 61. The support portion 664 rotatably supports the +X end of the second lead screw 82 about a rotation axis along the +X direction.

[0037] [Configuration of the second movable member] As shown in Figures 9 and 10, the second movable member 7 is positioned in the +Z direction relative to the frame 5 and is connected to the frame 5 by a connecting member 57. That is, of the frame 5, the first movable member 6, and the second movable member 7, the second movable member 7 is positioned furthest in the +Z direction and holds the lens barrel 361 of the projection optical device 36. The second movable member 7 has a first surface 7A facing the +Z direction and a second surface 7B facing the -Z direction, and also has an opening 71 approximately in the center through which a part of the lens barrel 361 of the projection optical device 36 is inserted along the +Z direction. As shown in Figure 9, the second movable member 7 has a holding portion 72 around the opening 71 that holds the lens barrel 361. As shown in Figure 3, the holding portion 72 holds the flange 362 provided on the lens barrel 361.

[0038] Figure 14 shows the second moving member 7 as viewed from the -Z direction. As shown in Figures 10 and 14, the second movable member 7 has an insertion pin 73, a second guide pin 74, and a second arrangement portion 75 provided on the second surface 7B. The insertion pins 73 are provided at each of the four corners of the second surface 7B of the roughly rectangular second movable member 7. Each insertion pin 73 protrudes from the second surface 7B in the -Z direction, and after each insertion pin 73 is inserted through the corresponding through-hole 55, the screw pin 572 of the connecting member 57 described above is fixed to each insertion pin 73 from the -Z direction. The surface around the insertion pin 73 on the second surface 7B is in contact with the surface around the through-hole 62 on the first surface 6A of the first movable member 6, and is a sliding surface that slides along the surface around the through-hole 62 when the second movable member 7 moves along the +X direction. The rotation of the second movable member 7 around the axis of rotation along the +X direction is restricted by the surface around the insertion pin 73 on the second surface 7B and the surface around the corresponding through-hole 62.

[0039] The second guide pin 74 is provided in the portion of the opening 61 that is in the +X direction and protrudes in the -Z direction. The second guide pin 74 is formed in a cylindrical shape when viewed from the -Z direction and is inserted into the second guide groove 65 of the first moving member 6 from the -Z direction when the first moving member 6 and the second moving member 7 are combined. In other words, the second guide pin 74, together with the second guide groove 65, constitutes the second guide portion GD2 that guides the movement of the second moving member 7 along the +X direction. The second placement section 75 is located on the opposite side of the opening 61 from the first guide pin 63. That is, the second placement section 75 is located in the -X direction relative to the opening 61. The second engagement member SM2 is placed in the second placement section 75. The second engagement member SM2 is fixed to the second placement section 75 by a fixing member such as a screw. The second interlocking member SM2 will be described in detail later.

[0040] [Drive System Configuration] The drive unit 8 moves the first movable member 6 and the second movable member 7 by the rotational force transmitted from the transmission unit 9. As shown in Figures 7 to 10, the drive unit 8 has a first lead screw 81 and a second lead screw 82.

[0041] [Configuration of the first lead screw] The first lead screw 81 corresponds to the first drive unit. The first lead screw 81 is positioned between the second mounting member 912 shown in Figures 7 and 8 and the support member 534 shown in Figure 11, and is rotatably supported by the second mounting member 912 and the support member 534 around a rotation axis along the +Y direction. The first lead screw 81 rotates around the rotation axis by the rotational force of the dial D1 transmitted by the first transmission unit 92. The first lead screw 81 then meshes with the first engagement member SM1, moving the first moving member 6, to which the first engagement member SM1 is connected, along the +Y direction.

[0042] Figure 15 is a perspective view of the first feed screw 81 and the first meshing member SM1, which constitute the drive unit 8, as seen from the +Y direction, and Figure 16 is a perspective view of the first feed screw 81 and the first meshing member SM1 as seen from the -Y direction. Figure 17 is a diagram showing cross-sections of the first feed screw 81 and the first meshing member SM1 along the XY plane. As shown in Figures 15 to 17, the first lead screw 81 has a first gear 811 and a second gear 812, as well as a biasing member 813 as shown in Figure 17, and these are combined to form the screw.

[0043] The first gear 811 is a gear that meshes with the third gear 924 of the first transmission unit 92. The first gear 811 has a hole 8111, a meshing portion 8112, an opening 8113, and a protrusion 8114. The hole 8111 is a hole into which the support portion 9121 provided in the second mounting member 912 is inserted. As a result, the first gear 811 is supported by the second mounting member 912 so as to be rotatable about a rotation axis Rx1 along the +Y direction. The meshing portion 8112 is provided on the outer circumferential surface of the first gear 811, centered on the rotation axis Rx1, and meshes with the third gear 924. The openings 8113 are provided at two locations on either side of the protrusion 8114 in a direction perpendicular to the rotation axis Rx1, and each opening 8113 passes through the first gear 811 along the +Y direction. The insertion portion 8123 of the second gear 812 is inserted into each opening 8113. As shown in Figure 17, the protruding portion 8114 is a part that protrudes in the +Y direction from around the hole portion 8111 and is formed in the shape of a bottomed cylinder. The protruding portion 8114 is inserted into the interior of the second gear 812 when the first gear 811 and the second gear 812 are assembled.

[0044] The second gear 812 is a cylindrical body positioned in the +Y direction relative to the first gear 811 and is combined with the first gear 811. That is, the second gear 812 rotates integrally with the first gear 811 around the rotation axis Rx1. The end of the second gear 812 opposite to the first gear 811, i.e., the end in the +Y direction, is supported by the support portion 534. The second gear 812 has an insertion opening 8121, a meshing portion 8122, an insertion portion 8123, and an internal boss 8124. The insertion opening 8121 penetrates the second gear 812 along the +Y direction. The insertion opening 8121 communicates with the hole 8111, and the support portion 9121 is inserted into the insertion opening 8121. The meshing portion 8122 is composed of helical teeth provided on the outer circumferential surface centered on the rotation axis Rx1. The meshing portion 8122 meshes with the meshing portion SM11 of the first meshing member SM1, which will be described later. The insertion portion 8123 protrudes in the -Y direction from the -Y end face of the second gear 812. The insertion portion 8123 is provided at two locations on either side of the insertion opening 8121, and each insertion portion 8123 is inserted into the corresponding opening 8113. As a result, the second gear 812 rotates integrally with the first gear 811. The internal boss 8124 is a cylindrical portion that protrudes in the -Y direction from the +Y end of the second gear 812 and surrounds the insertion opening 8121. The internal boss 8124 is inserted into the protruding portion 8114 when the first gear 811 and the second gear 812 are assembled.

[0045] As shown in Figure 17, the biasing member 813 is positioned inside the second gear 812 and applies a biasing force to the first gear 811 and the second gear 812 in a direction that moves them apart from each other. In this embodiment, the biasing member 813 is composed of a compression coil spring, and one end of the biasing member 813 contacts the +Y direction end of the protrusion 8114 of the first gear 811. The other end of the biasing member 813 contacts the inner surface of the second gear 812 where the internal boss 8124 protrudes in the -Y direction.

[0046] [Configuration of the first interlocking member] The first meshing member SM1 meshes with the first feed screw 81 and is fixed to the first positioning portion 64 of the first moving member 6 by a screw SC. In other words, the first meshing member SM1 is a part of the first moving member 6. As shown in Figures 15 to 17, the first meshing member SM1 has a meshing portion SM11 and a pair of fixing portions SM13 that sandwich the meshing portion SM11. The meshing portion SM11 has an arc-shaped meshing surface SM12 that covers half of the circumferential circumference of the second gear 812, and the meshing surface SM12 has multiple teeth that mesh with the helical teeth of the meshing portion 8122. In other words, the meshing portion SM11 meshes with the meshing portion 8122 of the second gear 812. For this reason, the meshing portion SM11 can be described as a load region to which a driving force is applied from the first lead screw 81 for the first moving member 6 to move along the +Y direction. Of the pair of fixing parts SM13, one fixing part SM13 extends in the +X direction from the +X end of the meshing part SM11, and the other fixing part SM13 extends in the -X direction from the -X end of the meshing part SM11. The pair of fixing parts SM13 are fixed to the first placement part 64 by a plurality of screws SC, thereby fixing the first meshing member SM1 to the first moving member 6. Then, when the dial D1 is rotated, the first feed screw 81 rotates via the first transmission unit 92. As a result, the first moving member 6, to which the first meshing member SM1 that meshes with the first feed screw 81 is fixed, moves in the direction along the rotation axis of the first feed screw 81, that is, along the +Y direction.

[0047] [Positional relationship between the first lead screw and the first guide section] Figure 18 shows a cross-section of the shift device 4 along the XY plane. More specifically, Figure 18 shows a cross-section of the shift device 4 along the XY plane passing through the center of the first feed screw 81 in the +Z direction. The positional relationship between the first lead screw 81 and the first guide part GD1 will be explained below. In this embodiment, the first lead screw 81, which serves as the first drive unit, and the first guide pin 63 and the first guide groove 52, which constitute the first guide unit GD1, are arranged on a virtual straight line L1 along the first direction, the +Y direction, with the opening 51 in between. That is, the first lead screw 81, the first guide pin 63, and the first guide groove 52 are arranged on the same virtual straight line L1 along the +Y direction, with the opening 51 in between, when viewed from the ±Z direction. The virtual straight line L1 corresponds to the first straight line and is a virtual line provided between the first inner surface 521 and the second inner surface 522 of the first guide groove 52. In this embodiment, it coincides with the rotation axis of the first lead screw 81.

[0048] Here, if the first lead screw 81, the first guide pin 63, and the first guide groove 52 are not positioned on the same virtual straight line L1 along the +Y direction, when the first lead screw 81 applies a driving force to move the first moving member 6 along the +Y direction, a rotational moment is generated that rotates the first moving member 6 around the contact point between the first guide pin 63 and the first guide groove 52. In such a case, the first moving member 6 may move while tilting with respect to the +Y direction, rather than moving in a straight line along the +Y direction. In such a case, the movement of the projection optical device 36 by the shift device 4 may cause the projection position of the image to shift from the position desired by the user. In contrast, in this embodiment, the first lead screw 81, the first guide pin 63, and the first guide groove 52 are arranged on the same virtual straight line L1 along the +Y direction. This suppresses the generation of the rotational moment described above. Therefore, the oblique movement of the first moving member 6 with respect to the +Y direction can be suppressed, and the projection position of the image can be prevented from shifting.

[0049] [Positional relationship between the meshing portion, which is the load area in the first moving member, and the third inner surface, which is the regulating surface] Figure 19 is a cross-sectional view of the frame 5 and the first moving member 6 along the YZ plane, showing the positional relationship between the meshing portion SM11 of the first meshing member SM1 and the third inner surface 523 that constitutes the first guide portion GD1. Note that the first lead screw 81 is not shown in Figure 19. In this embodiment, the movable end of the first movable member 6 in the ±Y direction is defined by the inner edge of the through-hole 55 through which the insertion pin 73 of the second movable member 7, which moves integrally with the first movable member 6 in the ±Y direction, is inserted. Alternatively, as described above, the movement of the first movable member 6 in the +Y direction may be restricted by the first guide pin 63 of the first movable member 6 contacting the third inner surface 523 that forms the first guide groove 52 of the frame 5. In this case, the positional relationship between the third inner surface 523 as the first restricting surface and at least a part of the meshing portion SM11 as the first load area will be explained. In this embodiment, as shown in Figure 19, the third inner surface 523 as the first regulating surface and at least a portion of the meshing portion SM11, which is the first load region to which driving force is applied from the first lead screw 81 in the first meshing member SM1, are arranged on the same virtual plane VP1 that is orthogonal to the +Z direction. That is, the third inner surface 523 and at least a portion of the meshing portion SM11 are arranged on the same virtual plane VP1 that is orthogonal to the optical axis of the projection optical device 36. Furthermore, the first reference portion, the first guide pin 63, the third inner surface 523, and at least a portion of the meshing portion SM11 are arranged on a virtual straight line L2 along the +Y direction.

[0050] The virtual surface VP1 is located between the end of the first guide pin 63 in the +Z direction and the end of the third inner surface 523 in the +Z direction, which is located in the -Z direction, and the end of the first guide pin 63 in the -Z direction and the end of the third inner surface 523 in the -Z direction, which is located in the +Z direction. The +Z direction corresponds to the first optical axis direction along the optical axis of the projection optical device 36, and the -Z direction corresponds to the second optical axis direction along the optical axis of the projection optical device 36. In this embodiment, the virtual surface VP1 is located between the +Z end of the third inner surface 523 and the -Z end of the first guide pin 63. That is, the virtual surface VP1 is located between the virtual surface VP2, which passes through the +Z end of the third inner surface 523 and is perpendicular to the +Z direction, and the virtual surface VP3, which passes through the -Z end of the first guide pin 63 and is perpendicular to the +Z direction.

[0051] Here, if the first guide pin 63, the third inner surface 523, and the meshing portion SM11 are not on the same plane, for example, if the first moving member 6 moves in the +Y direction and attempts to move further in the +Y direction from a state where the first guide pin 63 is in contact with the third inner surface 523, a rotational moment is generated that tilts the first moving member 6 with respect to a plane perpendicular to the optical axis of the projection optical device 36, centered on the contact point between the first guide pin 63 and the third inner surface 523. When the first moving member 6 is tilted with respect to the plane perpendicular to the optical axis of the projection optical device 36 due to this rotational moment, the focus position of the projected image by the projection optical device 36 shifts, and the projected image deteriorates.

[0052] In contrast, in this embodiment, since the first guide pin 63, the third inner surface 523, and at least a part of the meshing portion SM11 are located on the same virtual plane VP1, even if the first moving member 6 attempts to move further in the +Y direction from the state in which the first guide pin 63 is in contact with the third inner surface 523, the generation of the rotational moment can be suppressed. Therefore, degradation of the projected image can be suppressed. Furthermore, a portion of the insertion pin 73, a portion of the periphery of the through-hole 55 in the ±Y direction, and at least a portion of the meshing portion SM11 may be arranged on the same virtual plane perpendicular to the optical axis of the projection optical device 36.

[0053] [Configuration of the second lead screw and the second engagement member] Figure 20 shows a cross-section of the second lead screw 82 and the second meshing member SM2 along the XY plane. As shown in Figure 20, the second lead screw 82, which serves as the second drive unit, is rotatable around a rotation axis Rx2 along the +X direction and has the same configuration and function as the first lead screw 81. That is, the second lead screw 82 has a first gear 821, a second gear 822, and a biasing member 823, similar to the first gear 811, the second gear 812, and the biasing member 813. The first gear 821 has a hole 8211, a meshing portion 8212, an opening 8213, and a protruding portion 8214, similar to the hole 8111, meshing portion 8112, opening 8113, and protruding portion 8114. The second gear 822 has an insertion opening 8221, a meshing portion 8222, an insertion portion 8223, and an internal boss 8224, similar to the insertion opening 8121, meshing portion 8122, insertion portion 8123, and internal boss 8124.

[0054] The second meshing member SM2 has the same configuration and function as the first meshing member SM1 and is fixed to the second placement portion 75 of the second movable member 7. That is, the second meshing member SM2 has a meshing portion SM21, a meshing surface SM22 and a pair of fixing portions SM23, similar to the meshing portion SM11, meshing surface SM12 and pair of fixing portions SM13. When dial D2 is rotated, the second lead screw 82 rotates via the second transmission unit 93. As a result, the second moving member 7, to which the second meshing member SM2 that meshes with the second lead screw 82 is fixed, moves in the direction along the rotation axis of the second lead screw 82, i.e., in the +X direction. At this time, the second moving member 7 moves along the first moving member 6, so the member on which the second moving member 7 slides can also be said to be the first moving member 6 supported by the frame 5.

[0055] [Positional relationship between the second lead screw and the second guide section] Figure 21 shows a cross-section of the shift device 4 along the XY plane. More specifically, Figure 21 shows a cross-section of the shift device 4 along the XY plane passing through the center of the second lead screw 82 in the +Z direction. As shown in Figure 21, the second lead screw 82, which serves as the second drive unit, and the second guide pin 74 and second guide groove 65, which constitute the second guide GD2, are arranged on a virtual straight line L3 along the second direction, the +X direction, with the opening 61 in between. That is, the second lead screw 82 and the second guide GD2 are arranged on the same virtual straight line L3 along the +X direction. The virtual straight line L3 corresponds to the second straight line and is a virtual line provided between the first inner surface 651 and the second inner surface 652 of the second guide groove 65, and in this embodiment, it coincides with the rotation axis Rx2 of the second lead screw 82.

[0056] [Positional relationship between the meshing portion, which is the load area in the second moving member, and the third inner surface, which is the regulating surface] Figure 22 is a diagram showing cross-sections of the first moving member 6 and the second moving member 7 along the XZ plane, illustrating the positional relationship between the meshing portion SM21 of the second meshing member SM2 and the third inner surface 653 that constitutes the second guide portion GD2. Note that the second lead screw 82 is not shown in Figure 22. As shown in Figure 22, the third inner surface 653, which serves as the first regulating surface, and at least a portion of the meshing portion SM21, which is the second load region to which driving force is applied from the second lead screw 82 in the second meshing member SM2, are located on the same virtual plane VP4 perpendicular to the +Z direction. That is, the third inner surface 653 and at least a portion of the meshing portion SM21 are located on the same virtual plane VP4 perpendicular to the optical axis of the projection optical device 36. Furthermore, the second reference portion, the second guide pin 74, the third inner surface 653 which defines the moving end of the second moving member 7 in the +X direction, and at least a portion of the meshing portion SM21 are arranged on a virtual straight line L4 along the +X direction. In this embodiment, the second guide pin 74, the fourth inner surface 654 that defines the moving end of the second moving member 7 in the -X direction, and at least a portion of the meshing portion SM21 are arranged on the same virtual plane VP4 perpendicular to the +Z direction, and further arranged on a virtual straight line L4 along the +X direction.

[0057] [Effects of the Embodiment] The projector 1 according to this embodiment, as described above, provides the following effects. The projector 1 comprises a light source 30, a light modulator 343 that modulates the light emitted from the light source 30, a projection optical device 36 that projects the light modulated by the light modulator 343, and a shift device 4 that moves the projection optical device 36.

[0058] The shift device 4 is a shift device that moves the projection optical device 36, which projects an image, in the +X direction and the +Y direction, which are perpendicular to the optical axis of the projection optical device 36 and are mutually perpendicular. The +X direction corresponds to one of the first and second directions, and the +Y direction corresponds to the other of the first and second directions. The direction along the optical axis is the +Z direction. In the following explanation, the +Y direction will be considered the first direction. The shift device 4 comprises a frame 5, a first moving member 6, a first lead screw 81, and a first guide GD1. The first moving member 6 moves the projection optical device 36 along the +Y direction. The frame 5 has an opening 51 through which a portion of the projection optical device 36 is inserted, and supports the first moving member 6 so that it can move. The first lead screw 81 corresponds to the first drive unit and applies a first driving force to the first moving member 6, causing it to move along the +Y direction. The first guide unit GD1 guides the movement of the first moving member 6 along the +Y direction. The first lead screw 81 and the first guide GD1 are positioned on a virtual straight line L1 along the +Y direction, with the opening 51 in between. The virtual straight line L1 corresponds to the first straight line.

[0059] In this configuration, the first lead screw 81 and the first guide GD1 are positioned on a virtual straight line L1 with the opening 51 in between. As a result, when viewed from the +Z direction, neither the first lead screw 81 nor the first guide GD1 is misaligned with the other in the +X direction which is perpendicular to the +Y direction. Therefore, even when a driving force along the +Y direction is applied to the first moving member 6 by the first lead screw 81, the generation of a rotational moment that rotates the first moving member 6 in the plane perpendicular to the optical axis can be suppressed. Consequently, when such a driving force is applied, the first moving member 6 can be moved along the +Y direction, thus suppressing the first moving member 6 from moving obliquely with respect to the +Y direction. Therefore, since the first moving member 6 can be moved along the +Y direction without employing a slide guide device, the straight-line stability of the projection optical device 36 along the +Y direction can be improved. This allows the projection optical device 36 to be shifted stably, and the degradation of the projected image can be suppressed.

[0060] In the shift device 4, the first guide section GD1 includes a first guide pin 63 provided on the first moving member 6, which is one of the frame 5 and the first moving member 6, and a first guide groove 52 provided on the other member, extending in the +Y direction, and in which the first guide pin 63 is located. The first guide pin 63 is arranged to be movable along the +Y direction within the first guide groove 52. With this configuration, the first guide section GD1 can be made up of a first guide pin 63 and a first guide groove 52, so the first guide section GD1 can be easily constructed. Therefore, the shift device 4 can be constructed at low cost.

[0061] In the shift device 4, the virtual straight line L1 is located between the first inner surface 521 facing the +X direction and the second inner surface 522 facing the -X direction in the first guide groove 52. With this configuration, the virtual straight line L1 is located between the first inner surface 521 and the second inner surface 522 in the +X direction, which suppresses the generation of the rotational moment when the first driving force along the +Y direction acts on the first moving member 6. Therefore, when the first moving member 6 moves along the +Y direction due to the first driving force, the oblique movement of the first moving member 6 with respect to the +Y direction can be suppressed.

[0062] In the shift device 4, the first drive unit is a first lead screw 81 that is mounted on the frame 5 by a second mounting member 912 so as to be rotatable about a rotation axis Rx1 along the +Y direction, and applies a first driving force to the first moving member 6 by rotating. The virtual straight line L1 coincides with the rotation axis Rx1 of the first lead screw 81. With this configuration, when the first lead screw 81 is rotated and the first moving member 6 moves along the +Y direction, the generation of the rotational moment can be suppressed.

[0063] In the shift device 4, the first feed screw 81 has a first gear 811, a second gear 812, and a biasing member 813. The first gear 811 receives the rotational force necessary to rotate the first lead screw 81. The second gear 812 rotates integrally with the first gear 811. The second gear 812 has helical teeth on its outer surface that are aligned in the +Y direction and mesh with the first meshing member SM1 which is fixed to the first moving member 6. The biasing member 813 is provided between the first gear 811 and the second gear 812 in the +Y direction. The biasing member 813 biases the second gear 812 in a direction away from the first gear 811 along the +Y direction. With this configuration, looseness between the first feed screw 81 and the support portion 534 and the second mounting member 912 can be suppressed, and contact between the second gear 812 of the first feed screw 81 and the first meshing member SM1 can be made easier. As a result, the free rotation of the dial D1 can be reduced, and consequently, the projection optical device 36 can be moved in response to the operation of the dial D1. Therefore, the operability of the shift device 4 can be improved. Furthermore, by providing the biasing member 813 inside the first lead screw 81, the size of the shift device 4 along the +Y direction can be reduced compared to the case where the biasing member is positioned to apply a biasing force to the entire first lead screw 81 to maintain the contact state between the second gear 812 and the first meshing member SM1. Therefore, the shift device 4 can be miniaturized. Furthermore, the second lead screw 82, which is positioned between the support portion 664 and the third mounting member 913 and engages with the second meshing member SM2, has the same configuration as the first lead screw 81. Therefore, the second lead screw 82 can also achieve the same effects as described above.

[0064] In the shift device 4, the frame 5 has a first meshing member SM1 which engages with the first lead screw 81 on the first moving member 6, and a first guide recess 53 which guides the movement of the first moving member 6 along the +Y direction. The first guide recess 53 is provided on the opposite side of the opening 51 from the first guide portion GD1. With this configuration, the movement of the first moving member 6 along the +Y direction is guided by the first guide portion GD1 and the first guide recess 53. This allows the first moving member 6 to move stably along the +Y direction.

[0065] The shift device 4 includes a second moving member 7, a second lead screw 82, and a second guide section GD2. The second moving member 7 moves the projection optical device 36 along the +X direction. The second lead screw 82 corresponds to a second drive unit. The second lead screw 82 applies a driving force to the second moving member 7, causing it to move along the +X direction. The second guide section GD2 guides the movement of the second moving member 7 along the +X direction. The second lead screw 82 and the second guide section GD2 are positioned on a virtual straight line L3 along the +X direction. The virtual straight line L3 corresponds to a virtual second straight line. With this configuration, similar to the first moving member 6, it is possible to suppress the generation of a rotational moment that rotates the second moving member 7 when it moves along the +X direction by the second lead screw 82. Therefore, since it is possible to suppress the second moving member 7 from moving obliquely with respect to the +X direction, the second moving member 7 can be moved along the +X direction, and the straight-line stability of the projection optical device 36 along the +X direction can be improved.

[0066] [Variations of the Embodiment] This disclosure is not limited to the embodiments described above, and any modifications and improvements that can achieve the objectives of this disclosure are included. In the above embodiment, the shift device 4 is equipped with dials D1 and D2 operated by the user, and the rotational force of dials D1 and D2 is transmitted to the respective feed screws 81 and 82 of the drive device 8. In other words, the projection optical device 36 is moved manually. However, the present disclosure is not limited to this, and the shift device may also shift the projection optical device 36 electrically.

[0067] In the above embodiment, the first guide portion GD1 is composed of a first guide pin 63 and a first guide groove 52, and the second guide portion GD2 is composed of a second guide pin 74 and a second guide groove 65. However, the configuration of the guide portion is not limited to the above, as long as it can guide the movement of the moving member. For example, the guide portion may be composed of a rib and a groove, or the guide portion and the biasing portion may be integrated, such as in a dovetail groove.

[0068] In the above embodiment, the movement of the first moving member 6 is guided not only by the first guide portion GD1 but also by the first guide recess 53 of the frame 5, and the movement of the second moving member 7 is guided not only by the second guide portion GD2 but also by the second guide recess 66 of the first moving member 6. In other words, there are two configurations for guiding the movement of the moving members. However, the number of configurations for guiding the movement of the moving members can be one or three or more. For example, if the shift device 4 is equipped only with the first guide portion GD1 as a configuration for guiding the movement of the first moving member 6, the length of the first guide groove 52 in the +Y direction may be increased. Furthermore, the first guide recess 53 may restrict the rotation of the first moving member 6 about a rotation axis along the +Y direction, and the second guide recess 66 may restrict the rotation of the second moving member 7 about a rotation axis along the +X direction.

[0069] In the above embodiment, the frame 5, the first movable member 6, and the second movable member 7 are each biased by a connecting member 57 having a biasing member 573. However, the embodiment is not limited to this, and at least one of the frame 5, the first movable member 6, and the second movable member 7 may be biased using an elastic member such as a leaf spring, wire spring, or rubber, and a magnet or the like. Furthermore, the parts that bias the frame 5, the first movable member 6, and the second movable member 7 are not limited to the four corners of each component, but may be located elsewhere, and the number of biasing points is not limited to four. Furthermore, it is not necessary to bias each of the frame 5, the first moving member 6, and the second moving member 7 using a biasing member. For example, the frame 5 and the second moving member 7 that holds the projection optical device 36 may be biased by a biasing member, while the first moving member 6 interposed between the frame 5 and the second moving member 7 does not need to be biased.

[0070] In the above embodiment, the first moving member 6 moves along the +Y direction relative to the frame 5, and the second moving member 7 moves along the +X direction relative to the frame 5. However, the embodiment is not limited to this, and the first moving member 6 may also move along the +X direction, and the second moving member 7 may also move along the +Y direction. Furthermore, the movement directions of the first moving member 6 and the second moving member 7 are not limited to the ±X and ±Y directions, but may also be in a direction inclined with respect to the ±X and ±Y directions.

[0071] In the above embodiment, of the two moving members 6 and 7, the second moving member 7, which is located on the image light emission side, holds the projection optical device 36. However, the embodiment is not limited to this, and the first moving member 6 may also hold the projection optical device 36.

[0072] In the above embodiment, the shift device 4 is described as having a first moving member 6 and a second moving member 7 as moving members for moving the projection optical device 36. However, it is not limited to these, and the number of such moving members may be three or more.

[0073] In the above embodiment, a first lead screw 81 was given as the first drive unit that applies a first driving force to the first moving member 6, and a second lead screw 82 was given as the second drive unit that applies a second driving force to the second moving member 7. However, the embodiment is not limited to these, and a driving force may be applied to the moving members by a configuration other than a lead screw. For example, a lever may be used in at least one of the first drive unit and the second drive unit, and the moving member may be moved by the lever. Furthermore, the biasing members 813 and 823 used in the lead screws 81 and 82 are not limited to compression coil springs, but may be other spring members such as leaf springs and wire springs, or elastic members such as rubber.

[0074] In the above embodiment, the rotational force of dial D1 is transmitted to the first lead screw 81 by gears 921 to 924 constituting the first transmission unit 92, and the rotational force of dial D2 is transmitted to the second lead screw 82 by gears 931 to 933 constituting the second transmission unit 93. However, the number of gears constituting each transmission unit 92, 93 can be changed as appropriate. Furthermore, each transmission unit 92, 93 is not limited to a configuration that transmits rotational force using gears; for example, pulleys may also be used. Furthermore, one of the transmission units 92 and 93 may be omitted. In this case, one of the dials D1 and D2 may be directly connected to one of the lead screws 81 and 82.

[0075] In the above embodiment, the biasing member 813 of the first lead screw 81 is provided between the first gear 811 and the second gear 812. That is, the biasing member 813 is sandwiched between the first gear 811 and the second gear 812. However, the embodiment is not limited to this, and for example, a configuration may be provided in the second mounting member 912 to hold the biasing member 813, and the configuration in which the first gear 811 and the second gear 812 are integrated by the biasing member 813 may be biased to the meshing member.

[0076] In the above embodiment, the first meshing member SM1 is fixed to the first movable member 6 by a screw SC, and the second meshing member SM2 is fixed to the second movable member 7 by a screw SC. However, the embodiment is not limited to this, and the first meshing member SM1 and the first movable member 6 may be integrated in a way that prevents separation. The same applies to the second meshing member SM2 and the second movable member 7.

[0077] In the above embodiment, the projector 1 is provided with three optical modulators 343R, 343G, and 343B. However, the present disclosure is not limited to this and can also be applied to projectors equipped with two or fewer optical modulators, or four or more optical modulators.

[0078] In the above embodiment, the optical modulator 343 is provided with a transmissive liquid crystal panel where the light incident surface and the light output surface are different. However, the optical modulator 343 is not limited to this, and may also be provided with a reflective liquid crystal panel where the light incident surface and the light output surface are the same. Furthermore, any optical modulator capable of modulating the incident light beam to form an image corresponding to image information may be used, such as a device using a micromirror, for example, a DMD (Digital Micromirror Device), or other optical modulators other than liquid crystals.

[0079] [Summary of this disclosure] A summary of this disclosure is provided below. [Note 1] A shift device for moving a projection optical device that projects an image in a first direction perpendicular to the optical axis of the projection optical device, A first moving member for moving the aforementioned projection optical device, A frame having an opening through which the projection optical device is inserted, and which movably supports the first movable member, A first drive unit that applies a driving force to the first moving member to move the first moving member along the first direction, A first guide portion that guides the movement of the first moving member along the first direction, Equipped with, The first drive unit and the first guide unit are arranged on a virtual first straight line along the first direction, with the opening in between. A shift device characterized by the following features.

[0080] With this configuration, the first drive unit and the first guide unit are arranged on a virtual first straight line with the opening in between. As a result, when viewed along the optical axis, neither the first drive unit nor the first guide unit is misaligned with respect to the other in a direction perpendicular to the first direction. Therefore, even when a driving force along the first direction is applied to the first moving member by the first drive unit, the generation of a rotational moment that rotates the first moving member can be suppressed. Consequently, when such a driving force is applied, the first moving member can be moved along the first direction, thus suppressing the first moving member from moving obliquely with respect to the first direction. Therefore, since the first moving member can be moved along the first direction without employing the slide guide device described above, the straight-line stability of the projection optical device along the first direction can be improved.

[0081] [Note 2] In the shift device described in Appendix 1, The first guide section is, A first guide pin is provided on one of the first moving member and the frame, The first movable member and the other member of the frame are provided with a first guide groove that extends in the first direction and has the first guide pin positioned inside, The first guide pin is positioned within the first guide groove so as to be movable along the first direction. A shift device characterized by the following features. With this configuration, the first guide section can be made up of a first guide pin and a first guide groove, allowing for a simple construction of the first guide section. Therefore, the shift device can be constructed at a low cost.

[0082] [Note 3] In the shift device described in Appendix 2, The first straight line is located in the first guide groove between a first inner surface that faces a second direction perpendicular to the optical axis and the first direction, and a second inner surface that faces a direction opposite to the second direction. A shift device characterized by the following features. With this configuration, the first straight line is positioned between the first inner surface and the second inner surface in the second direction, thereby suppressing the generation of the rotational moment when a driving force along the first direction acts on the first moving member. Consequently, when the first moving member moves along the first direction due to the driving force, the oblique movement of the first moving member with respect to the first direction can be suppressed.

[0083] [Note 4] In the shift device described in any one of the appendices 1 to 3, The first drive unit is a lead screw that is mounted on the frame so as to be rotatable about a rotation axis along the first direction, and applies the first driving force to the first moving member by rotating. The first straight line coincides with the rotation axis of the lead screw. A shift device characterized by the following features. With this configuration, when the lead screw is rotated and the first moving member moves along the first direction, the generation of the rotational moment can be suppressed.

[0084] [Note 5] In the shift device described in Appendix 4, The aforementioned lead screw is A first gear to which the rotational force that rotates the lead screw is transmitted, A second gear rotates integrally with the first gear, has helical teeth on its outer surface oriented in the first direction, and meshes with the first moving member, A biasing member is provided between the first gear and the second gear, and biases the second gear in a direction that moves away from the first gear along the first direction, A shift device characterized by the following features. This configuration suppresses play between the second gear and the first moving member. Furthermore, by providing a biasing member inside the lead screw, the size of the shift device along the first direction can be reduced compared to the case where the biasing member is positioned to apply a biasing force to the entire lead screw to maintain contact between the second gear and the first moving member. Consequently, the shift device can be miniaturized.

[0085] [Note 6] In the shift device described in Appendix 4 or Appendix 5, The frame has a portion of the first moving member that engages with the lead screw, and a first guide recess that guides the movement of the first moving member along the first direction. The first guide recess is provided on the opposite side of the opening from the first guide portion. A shift device characterized by the following features. With this configuration, the movement of the first moving member along the first direction is guided by the first guide portion and the first guide recess. This allows the first moving member to move stably along the first direction.

[0086] [Note 7] In the shift device described in any one of the appendices 1 to 6, A second moving member moves the projection optical device along a second direction perpendicular to the optical axis and the first direction, A second drive unit that applies a driving force to the second moving member to move the second moving member along the second direction, A second guide portion that guides the movement of the second moving member along the second direction, Equipped with, The second drive unit and the second guide unit are arranged on a virtual second straight line along the second direction. A shift device characterized by the following features. With this configuration, similar to the first moving member, it is possible to suppress the generation of a rotational moment that rotates the second moving member when the second moving member is moved along the second direction by the second drive unit. Therefore, since it is possible to suppress the second moving member from moving obliquely with respect to the second direction, the second moving member can be moved along the second direction without employing the slide guide device described above, and the straight-line stability of the projection optical device along the second direction can be improved.

[0087] [Note 8] Light source and A light modulation device that modulates the light emitted from the aforementioned light source, A projection optical device that projects light modulated by the aforementioned optical modulation device, The projecting optical device comprises a shift device described in any one of the appendices 1 to 7 for moving the aforementioned projection optical device, A projector characterized by the following features. Such projectors can achieve the same effect as the shift device described above, allowing for stable shifting of the projection optical system and suppressing degradation of the projected image. [Explanation of Symbols]

[0088] 1...Projector, 30...Light source, 343...Light modulation device, 36...Projection optics device, 361...Lens barrel, 4...Shift device, 5...Frame, 51...Aperture, 52...First guide groove, 53...First guide recess, 6...First moving member, 61...Aperture, 63...First guide pin, 65...Second guide groove, 66...Second guide recess, 7...Second moving member, 71...Aperture, 74...Second guide pin, 8...Driver Movement mechanism, 81...First lead screw (first drive unit), 811...First gear, 812...Second gear, 813...Biasing member, 82...Second lead screw (second drive unit), 821...First gear, 822...Second gear, 823...Biasing member, GD1...First guide part, GD2...Second guide part, L1...Virtual straight line (first straight line), L3...Virtual straight line (second straight line), SM1...First meshing member, SM2...Second meshing member.

Claims

1. A shift device for moving a projection optical device that projects an image in a first direction perpendicular to the optical axis of the projection optical device, A first moving member for moving the aforementioned projection optical device, A frame having an opening through which the projection optical device is inserted, and which movably supports the first movable member, A first drive unit that applies a first driving force to the first moving member to move the first moving member along the first direction, A first guide portion that guides the movement of the first moving member along the first direction, Equipped with, The first drive unit and the first guide unit are arranged on a virtual first straight line along the first direction, with the opening in between. A shift device characterized by the following features.

2. In the shift device according to claim 1, The first guide section is, A first guide pin is provided on one of the first moving member and the frame, The first movable member and the other member of the frame are provided with a first guide groove that extends in the first direction and has the first guide pin disposed inside, The first guide pin is positioned within the first guide groove so as to be movable along the first direction. A shift device characterized by the following features.

3. In the shift device according to claim 2, The first straight line is located in the first guide groove between a first inner surface that faces a second direction perpendicular to the optical axis and the first direction, and a second inner surface that faces a direction opposite to the second direction. A shift device characterized by the following features.

4. In the shift device according to any one of claims 1 to 3, The first drive unit is a lead screw that is mounted on the frame so as to be rotatable about a rotation axis along the first direction, and applies a first driving force to the first moving member by rotating. The first straight line coincides with the rotation axis of the lead screw. A shift device characterized by the following features.

5. In the shift device according to claim 4, The aforementioned lead screw is A first gear to which the rotational force that rotates the aforementioned lead screw is transmitted, A second gear rotates integrally with the first gear, has helical teeth on its outer surface oriented in the first direction, and meshes with the first moving member. A biasing member is provided between the first gear and the second gear, and biases the second gear in a direction that moves away from the first gear along the first direction. A shift device characterized by the following features.

6. In the shift device according to claim 4, The frame has a portion of the first moving member that engages with the lead screw, and a first guide recess that guides the movement of the first moving member along the first direction. The first guide recess is provided on the opposite side of the opening from the first guide portion. A shift device characterized by the following features.

7. In the shift device according to claim 1 or claim 2, A second moving member moves the projection optical device along a second direction perpendicular to the optical axis and the first direction, A second drive unit that applies a second driving force to the second moving member to move the second moving member along the second direction, A second guide portion that guides the movement of the second moving member along the second direction, Equipped with, The second drive unit and the second guide unit are arranged on a virtual second straight line along the second direction. A shift device characterized by the following features.

8. Light source and A light modulation device that modulates the light emitted from the aforementioned light source, A projection optical device that projects light modulated by the aforementioned optical modulation device, The projected optical device is moved by a shift device according to any one of claims 1 to 3, A projector characterized by the following features.

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