projector

Abstract

To provide a projector with which it is possible to project an enlarged image having the same resolution to first and second projection positions by switching therebetween.SOLUTION: The projector comprises a light modulation element and a projection mechanism. The projection mechanism has a first optical system, a second optical system, and a shift mechanism that moves the second optical system. The shift mechanism moves the second optical system to a first position and to a second position different from the first position, in a direction orthogonal to the optical axis of the second optical system. When the second optical system is at the first position, the projection mechanism causes projection image light to go through a first projection optical system composed of the second and first optical systems and projects a first enlarged image of projection image to a first projection position. When the second optical system is at the second position, the projection mechanism causes the projection image light to go through a second projection optical system composed only of the second optical system and projects a second enlarged image of projection image to a second projection position that is different from the first projection position at a field angle that is different from the field angle of the first projection optical system.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a projector. [Background technology]

[0002] Patent Document 1 describes a projector that uses a projection optical system to enlarge projection images displayed in different first and second display regions of a single image display element and project them onto different first and second planes. In this document, the first display region is larger than the second display region. The projection optical system includes a first optical system that projects onto the first plane, a second optical system that projects onto the second plane, and a common optical system that causes the projection image displayed in the first display region of the image display element to enter the first optical system and the projection image displayed in the second display region of the image display element to enter the second optical system. The optical axis of the first optical system coincides with the optical axis of the common optical system. The second optical system is composed of two mirrors located at a distance from the optical axis of the common optical system. The first angle of view projected by the first optical system and the common optical system and the second angle of view projected by the second optical system and the common optical system overlap, and the first image and the second image are simultaneously projected onto the first and second planes, respectively. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2019 / 064977 publication Summary of the Invention [Problem to be solved by the invention]

[0004] In the above projector, the image display element is divided into a first display area, a second display area, and an overlapping area. Therefore, since the area of the image display element is divided into an area projected onto the first plane and an area projected onto the second plane, there is a risk that the resolution will be significantly reduced. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, a projection optical system of the present invention includes a light modulation element that forms a projection image, and a projection mechanism that enlarges and projects projection image light of the projection image emitted from the light modulation element, wherein the projection mechanism includes a first optical system, a second optical system that is positioned between the first optical system and the light modulation element, and a projection mechanism that projects the projection image light of the projection image emitted from the light modulation element. No. and a shift mechanism for moving the second optical system, wherein the shift mechanism moves the second optical system in a direction perpendicular to the optical axis of the second optical system to a first position and a second position different from the first position, and when the second optical system is at the first position, the projection mechanism passes the projection image light through a first projection optical system consisting of the second optical system and the first optical system to project a first enlarged image of the projection image at the first projection position, and when the second optical system is at the second position, the projection mechanism passes the projection image light through a second projection optical system consisting only of the second optical system to project a second enlarged image of the projection image at a second projection position different from the first projection position with a different angle of view from the angle of view of the first projection optical system. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a projector according to an embodiment of the present invention. [Figure 2] FIG. [Figure 3] 1 is a ray diagram that schematically illustrates the entire projection mechanism of the first embodiment. [Figure 4] FIG. 3 is a ray diagram of the projection mechanism of the first embodiment. [Figure 5] FIG. 4 is a ray diagram of a projection mechanism of a second embodiment in the first embodiment. [Figure 6] 3A and 3B are diagrams illustrating the positional relationship between the projection optical system and the display area of the liquid crystal panel. [Figure 7] 4 is a diagram showing the MTF on the enlargement side of the projection mechanism of the first form in Example 1. FIG. [Figure 8] 10 is a diagram showing the MTF on the enlargement side of the projection mechanism of the second embodiment in Example 1. FIG. [Figure 9] FIG. 10 is a ray diagram that schematically illustrates the entire projection mechanism of the second embodiment. [Figure 10] FIG. 10 is a ray diagram of a projection mechanism of a first embodiment in the second embodiment. [Figure 11] FIG. 10 is a ray diagram of a projection mechanism of a second embodiment in the second embodiment. [Figure 12] FIG. 10 is a ray diagram that schematically illustrates the entire projection mechanism of the third embodiment. [Figure 13] FIG. 10 is a ray diagram of a projection mechanism of a first embodiment in the third embodiment. [Figure 14] FIG. 10 is a ray diagram of a projection mechanism of a second embodiment in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] DETAILED DESCRIPTION OF THE INVENTION A projector according to an embodiment of the invention will be described in detail below with reference to the drawings.

[0008] (projector) 1 is a schematic configuration diagram of a projector equipped with a projection mechanism 3 of the present invention. As shown in Fig. 1, the projector 1 is equipped with an image forming unit 2 that forms a projection image to be projected onto a screen S, a projection mechanism 3 that enlarges the projection image light of the projection image emitted from the image forming unit 2 and projects it onto the screen S, and a control unit 4 that controls the operation of the image forming unit 2.

[0009] (Image generation optical system and control unit) The image forming unit 2 includes a light source 10, a first integrator lens 11, a second integrator lens 12, a polarization conversion element 13, and a superimposing lens 14. The light source 10 is, for example, an ultra-high pressure mercury lamp, a solid-state light source, or the like. The first integrator lens 11 and the second integrator lens 12 each have a plurality of lens elements arranged in an array. The first integrator lens 11 splits the light beam from the light source 10 into a plurality of beams. Each lens element of the first integrator lens 11 focuses the light beam from the light source 10 near each lens element of the second integrator lens 12.

[0010] Polarization conversion element 13 converts the light from second integrator lens 12 into predetermined linearly polarized light. Superimposing lens 14 superimposes the images of each lens element of first integrator lens 11 via second integrator lens 12 onto the display areas of liquid crystal panels 18R, 18G, and 18B, which will be described later.

[0011] The image forming unit 2 also includes a first dichroic mirror 15, a reflecting mirror 16, a field lens 17R, and a liquid crystal panel 18R. The first dichroic mirror 15 reflects the R light, which is a portion of the light beam incident from the superimposing lens 14, and transmits the G light and B light, which are also portions of the light beam incident from the superimposing lens 14. The R light reflected by the first dichroic mirror 15 passes through the reflecting mirror 16 and the field lens 17R and is incident on the liquid crystal panel 18R. The liquid crystal panel 18R is a light modulation element. The liquid crystal panel 18R modulates the R light in accordance with an image signal to form a red projection image.

[0012] The image forming unit 2 further includes a second dichroic mirror 21, a field lens 17G, and a liquid crystal panel 18G. The second dichroic mirror 21 reflects G light, which is a portion of the light beam from the first dichroic mirror 15, and transmits B light, which is a portion of the light beam from the first dichroic mirror 15. The G light reflected by the second dichroic mirror 21 passes through the field lens 17G and enters the liquid crystal panel 18G. The liquid crystal panel 18G is a light modulation element. The liquid crystal panel 18G forms a green projection image by modulating the G light in accordance with an image signal.

[0013] The image forming unit 2 also includes a relay lens 22, a reflecting mirror 23, a relay lens 24, a reflecting mirror 25, a field lens 17B, and a liquid crystal panel 18B. The B light transmitted through the second dichroic mirror 21 passes through the relay lens 22, the reflecting mirror 23, the relay lens 24, the reflecting mirror 25, and the field lens 17B, and is incident on the liquid crystal panel 18B. The liquid crystal panel 18B is a light modulation element. The liquid crystal panel 18B forms a blue projection image by modulating the B light in accordance with an image signal.

[0014] Liquid crystal panels 18R, 18G, and 18B surround cross dichroic prism 19 on three sides. Cross dichroic prism 19 is a prism for light synthesis, and generates a projection image by synthesizing the light modulated by each of liquid crystal panels 18R, 18G, and 18B.

[0015] Here, the projection mechanism 3 enlarges the projection image (the projection image formed by each of the liquid crystal panels 18R, 18G, and 18B) combined by the cross dichroic prism 19 and projects the enlarged image onto the screen S. The screen S is the enlargement-side image formation surface of the projection mechanism 3.

[0016] The control unit 4 includes an image processing unit 6 to which external image signals such as video signals are input, and a display driving unit 7 that drives the liquid crystal panels 18R, 18G, and 18B based on the image signals output from the image processing unit 6.

[0017] Image processing unit 6 converts an image signal input from an external device into an image signal including the gradation of each color. Display drive unit 7 operates liquid crystal panels 18R, 18G, and 18B based on the projection image signals of each color output from image processing unit 6. As a result, image processing unit 6 displays a projection image corresponding to the image signal on liquid crystal panels 18R, 18G, and 18B.

[0018] (Projection mechanism) Below, Examples 1 to 3 will be described as configuration examples of the projection mechanism 3 mounted on the projector 1. In Examples 1 to 3, the projection mechanism 3 includes a projection optical system 30 and a shift mechanism 41. The projection optical system 30 includes a first optical system 31 and a second optical system 32 positioned between the first optical system 31 and the liquid crystal panel 18. The shift mechanism 41 moves the second optical system 32 relative to the liquid crystal panel 18 in a direction perpendicular to the optical axis N of the second optical system 32.

[0019] FIG. 2 is an explanatory diagram of the shift mechanism 41. The shift mechanism 41 includes, for example, a holder 42 that holds the second optical system 32 of the projection optical system 30, a support 43 that supports the holder 42 so that it can move in a direction perpendicular to the optical axis N of the second optical system 32, and a drive mechanism 44 that moves the holder 42 to the first position 32A or the second position 32B. In this example, when the holder 42 that holds the second optical system 32 moves to the first position 32A or the second position 32B, the first optical system 31 moves integrally with the second optical system 32. In other words, the holder 42 also holds the first optical system 31. At this time, the optical axis N of the second optical system 32 coincides with the optical axis N of the first optical system 31. The optical axis N of the second optical system 32 is also the optical axis N of the projection optical system 30. Therefore, in this example, the shift mechanism 41 moves the first optical system 31 and the second optical system 32 (projection optical system 30) relative to the liquid crystal panel 18 in a direction perpendicular to the optical axis N of the projection optical system 30.

[0020] For convenience, in the following description, three mutually orthogonal axes are referred to as the X-axis, Y-axis, and Z-axis. The direction along the optical axis N of the projection optical system 30 is referred to as the Z-axis direction. In the Z-axis direction, the side where the first optical system 31 is located is referred to as the first direction Z1, and the side where the second optical system 32 is located is referred to as the second direction Z2. The up-down direction is referred to as the Y-axis direction. In the Y-axis direction, one side is referred to as the upper side Y1, and the other side is referred to as the lower side Y2.

[0021] The drive mechanism 44 includes a drive unit 45 that moves the holder 42 to the first position 32A or the second position 32B in the Y-axis direction. The drive mechanism 44 includes a selector 46 that selectively positions the projection optical system 30 at the first position 32A or the second position 32B. The drive unit 45 is a drive source such as a motor. The selector 46 is a switch or the like that allows the user to select each position of the projection optical system 30. The control unit 4 includes a shift control unit 47 that drives and controls the drive unit 45. The shift control unit 47 stores position information of the holder 42, and drives and controls the drive unit 45 to position the holder 42 at the first position 32A or the second position 32B based on the position information selected by the selector 46.

[0022] When the selection unit 46 selects to place the projection optical system 30 at the first position 32A, the drive unit 45 is driven and controlled to place the holding unit 42 at the first position 32A. When the selection unit 46 selects to place the second optical system 32 at the second position 32B, the drive unit 45 is driven and controlled to place the projection optical system 30 at the second position 32B. This causes the shift mechanism 41 to move the projection optical system 30 to the first position 32A or the second position 32B in the Y-axis direction.

[0023] When the projection optical system 30 is at the first position 32A, the shift mechanism 41 moves the projection optical system 30 upward Y1. When the projection optical system 30 is at the second position 32B, the shift mechanism 41 moves the projection optical system 30 downward Y2. Here, when the projection optical system 30 is at the first position 32A, the optical axis N1 of the projection optical system 30 is located above the liquid crystal panel 18 at Y1, and when the projection optical system 30 is at the second position 32B, the optical axis N2 of the projection optical system 30 is located below the liquid crystal panel 18 at Y2. Note that the shift mechanism 41 may be configured to move the projection optical system 30 in the X-axis direction.

[0024] In the explanation of the projection mechanism of each of Examples 1 to 3, the first mode is when the projection optical system 30 is disposed at the first position 32A, and the second mode is when the projection optical system 30 is disposed at the second position 32B, and these are shown side by side. Also, in each of Examples 1 to 3, in the light ray diagrams of the projection mechanism, the liquid crystal panel 18R, the liquid crystal panel 18G, and the liquid crystal panel 18B are represented as the liquid crystal panel 18.

[0025] Example 1 FIG. 3 is a ray diagram that schematically illustrates the entire projection mechanism 3A of Example 1. FIG. 4 is a ray diagram of the projection mechanism 3A in a first embodiment of Example 1. FIG. 5 is a ray diagram of the projection mechanism 3A in a second embodiment of Example 1. FIG. 6 is a diagram that explains the positional relationship between the projection optical system 30 and the display area of the liquid crystal panel 18. Note that in FIG. 3, the ray of the projection mechanism 3A in the first embodiment and the ray of the projection mechanism 3A in the second embodiment are overlapped. In FIGS. 4 and 5, the shift mechanism is omitted. FIG. 6 shows an outline of the external shapes of the projection optical system 30 and the liquid crystal panel 18 in a plan view.

[0026] 3, in the first configuration, the projection mechanism 3A projects a first enlarged image projected from the first optical system 31 onto a first screen S1 located at a first projection position, and in the second configuration, the projection mechanism 3A projects a second enlarged image projected from the second optical system 32 onto a second screen S2 located at a second position different from the first position. In this example, the first screen S1 and the second screen S2 are parallel to each other, and the first screen S1 is located in the second direction Z2 from the second screen S2.

[0027] As shown in FIG. 3, the projection mechanism 3A of the first embodiment and the projection mechanism 3A of the second embodiment have different angles of view, and the projection mechanism 3A of the first embodiment is capable of wider-angle projection than the projection mechanism 3A of the second embodiment. In FIG. 3, the light beams reaching each screen S from the projection mechanism 3A of this example are schematically shown as light beams F1 to F4. Light beam F1 is the light beam that reaches the position with the lowest image height. Light beam F4 is the light beam that reaches the position with the highest image height. Light beams F2 and F3 are light beams that reach positions between light beams F1 and F4. Also, as shown in FIG. 3, the first projection distance of the projection mechanism 3A of the first embodiment is shorter than the second projection distance of the projection mechanism 3A of the second embodiment.

[0028] (First embodiment of the first embodiment) 3 and 4, in the projection mechanism 3A of the first embodiment, the projection optical system 30 is placed at a first position 32A by a shift mechanism. In the projection mechanism 3A of the first embodiment, a first projection optical system 30A is configured, which is made up of a first optical system 31 and a second optical system 32.

[0029] The liquid crystal panel 18 of the image forming unit 2 is disposed on a reduction-side image forming surface of the first projection optical system 30A. The first screen S1 is disposed on an enlargement-side image forming surface of the first projection optical system 30A.

[0030] The first optical system 31 includes three lenses L11 to L13. The lenses L11 to L13 are arranged in this order from the enlargement side to the reduction side. The second optical system 32 includes four lenses L21 to L24. The lenses L21 to L24 are arranged in this order from the enlargement side to the reduction side. A diaphragm 51 is arranged between the lenses L21 and L22. The diaphragm 51 is an aperture diaphragm that is set to define the F-number.

[0031] 4 and 6, when the projection optical system 30 is at the first position 32A, the optical axis N1 of the projection optical system 30 is located above Y1 the liquid crystal panel 18. In other words, the liquid crystal panel 18 is located below Y2 the optical axis N1 of the projection optical system 30.

[0032] 3 and 4, the light beam emitted from the liquid crystal panel 18 passes through the second optical system 32 and then travels upward Y1 along the optical axis N1. The light beam emitted from the second optical system 32 passes through the first optical system 31 and is then enlarged and projected upward Y1 to reach the first screen S1. That is, the projection mechanism 3A passes the projection image light through a first projection optical system 30A consisting of the second optical system 32 and the first optical system 31, and projects a first enlarged image onto the first screen S1.

[0033] (Second embodiment of the first embodiment) 3 and 5, in the projection mechanism 3A of the second embodiment, the projection optical system 30 is disposed at the second position 32B by the shift mechanism. More specifically, when the projection optical system 30 moves from the first position 32A to the second position 32B, the projection optical system 30 is moved downward Y2 by the shift mechanism and disposed at the second position 32B. In the projection mechanism 3A of the second embodiment, a second projection optical system 30B is configured that is composed of only the second optical system 32.

[0034] The liquid crystal panel 18 of the image forming unit 2 is disposed on a reduction-side image forming surface of the second projection optical system 30B. The second screen S2 is disposed on an enlargement-side image forming surface of the second projection optical system 30B.

[0035] 5 and 6, when the projection optical system 30 is at the second position 32B, the optical axis N2 of the projection optical system 30 is located at a position Y2 below the liquid crystal panel 18. In other words, the liquid crystal panel 18 is located at a position Y1 above the optical axis N2 of the projection optical system 30. The liquid crystal panel 18 forms a projected image of the same shape in the first and second configurations.

[0036] 3 and 5, the light beam emitted from the liquid crystal panel 18 passes through the second optical system 32, is enlarged and projected downward Y2 along the optical axis N2, and reaches the second screen S2. That is, the projection mechanism 3A passes the projected image light through the second projection optical system 30B, which is composed only of the second optical system 32, and projects a second enlarged image onto the second screen S2 at a different angle of view from the angle of view of the first projection optical system 30A.

[0037] (lens data) The lens data for the first projection optical system 30A in the first embodiment is as follows. Surface numbers are assigned in order from the enlargement side to the reduction side. The symbols refer to the lens, cross dichroic prism, and liquid crystal panel. R is the radius of curvature. d is the on-axis surface spacing. nd is the refractive index for the d-line. νd is the Abbe number for the d-line. The units of R and d are mm.

[0038] Code Surface number R d nd vd S1 0 0.00000 478.881632 L11 1 70.00000 6.284397 1.743972 44.85 2 23.48106 18.624820 L12 3 70.00000 2.000000 1.743972 44.85 4 27.58649 34.234393 L13 5 -89.48399 20.000000 1.668587 32.20 6 -38.52206 52.000000 L21 7 -30.83096 3.000000 1.493154 67.03 8 -75.13558 10.000000 L22,51 9 19.10319 3.000000 1.654590 33.24 10 15.19880 20.000000 L23 11 237.38194 7.000000 1.620410 60.32 12 -30.44543 10.000000 L24 13 28.93771 6.394419 1.641320 56.50 14 252.89129 10.000000 19 15 0.00000 24.720000 1.516800 64.17 16 0.00000 0.100000 18 17 0.00000 0.000000

[0039] Furthermore, when the focal length is f, the projection distance is D, the half angle of view θ, and the F-number is Fn, the data of the first projection optical system 30A in the first embodiment is as follows:

[0040] f 6.4693mm D 478mm θ 64.0° Fn 2.05

[0041] The lens data for the second projection optical system 30B in the second embodiment is as follows. Surface numbers are assigned in order from the magnification side to the reduction side. The symbols refer to the lens, cross dichroic prism, and liquid crystal panel. R is the radius of curvature. d is the on-axis surface spacing. nd is the refractive index for the d-line. νd is the Abbe number for the d-line. The units of R and d are mm.

[0042] Code Surface number R d nd vd S2 0 0.00000 1707.335643 L21 7 -30.83096 3.000000 1.493154 67.03 8 -75.13558 10.000000 L22,51 9 19.10319 3.000000 1.654590 33.24 10 15.19880 20.000000 L23 11 237.38194 7.000000 1.620410 60.32 12 -30.44543 10.000000 L24 13 28.93771 6.394419 1.641320 56.50 14 252.89129 10.000000 19 15 0.00000 24.720000 1.516800 64.17 16 0.00000 0.100000 18 17 0.00000 0.000000

[0043] Furthermore, when the focal length is f, the projection distance is D, the half angle of view θ, and the F-number is Fn, the data of the second projection optical system 30B in the second embodiment is as follows:

[0044] f 23.3575mm D 1840mm θ 18.0° Fn 2.05

[0045] Here, when the projection distance of the first projection optical system 30A is the first projection distance D1 and the projection distance of the second projection optical system 30B is the second projection distance D2, the second projection distance D2 is three times or more the first projection distance D1.

[0046] In this example, the first projection distance D1 is 478 mm, and the second projection distance D2 is 1840 mm. Therefore, the second projection distance D2 is 3.85 times the first projection distance D1.

[0047] Furthermore, when the half angle of view of the first projection optical system 30A is defined as the first angle of view, and the half angle of view of the second projection optical system 30B is defined as the second angle of view, the first angle of view is three times or more the second angle of view.

[0048] In this example, the first angle of view θ1 is 64.0° and the second angle of view θ2 is 18.0°. Therefore, the first angle of view is 3.55 times the second angle of view.

[0049] (Action and effect) The projector 1 of this example includes a liquid crystal panel 18 that forms a projection image, and a projection mechanism 3 that enlarges and projects projection image light of the projection image emitted from the liquid crystal panel 18. The projection mechanism 3 includes a first optical system 31, a second optical system 32 located between the first optical system 31 and the liquid crystal panel 18, and a shift mechanism 41 that moves the first optical system 31 and the second optical system 32 (projection optical system 30) relative to the liquid crystal panel 18. The shift mechanism 41 moves the projection optical system 30 between a first position 32A and a second position 32B different from the first position 32A in the Y-axis direction orthogonal to the optical axis N of the second optical system 32. When the projection optical system 30 is at the first position 32A, the projection mechanism 3 projects a first enlarged image onto a first screen S1 located at a first projection position, via the projection image light through a first projection optical system 30A consisting of the second optical system 32 and the first optical system 31. When the projection optical system 30 is at the second position 32B, the projection mechanism 3 projects a second enlarged image onto the second screen S2 located at the second projection position at a different angle of view from the angle of view of the first projection optical system 30A by passing the projection image light through the second projection optical system 30B consisting only of the second optical system 32. The liquid crystal panel 18 forms projection images of the same shape when the first optical system 31 and the second optical system 32 are at the first position 32A and the second position 32B.

[0050] According to this example, in a projector that can selectively change the first projection optical system 30A and the second projection optical system 30B, which have different angle of view and projection positions, the first projection optical system 30A and the second projection optical system 30B enlarge and project the projection image light of a projection image of the same shape, so that the resolution of each enlarged image projected onto the first screen S1 and the second screen S2 can be made the same.

[0051] In this example, when the second optical system 32 is moved by the shift mechanism 41, the first optical system 31 moves integrally with the second optical system 32. Therefore, compared to a configuration in which the first optical system 31 is fixed and only the second optical system 32 moves, it is possible to suppress misalignment of the optical axes of the first optical system 31 and the second optical system 32.

[0052] In this example, the second optical system 32 includes the diaphragm 51. Therefore, since the second optical system 32, which is common to the first projection optical system 30A and the second projection optical system 30B, includes the diaphragm, the size of the light beam passing through the diaphragm 51 in the first projection optical system 30A and the second projection optical system 30B is equivalent. Therefore, the F-numbers of the first projection optical system 30A and the second projection optical system 30B can be made equivalent.

[0053] In this example, when the projection distance of the first projection optical system 30A is the first projection distance D1 and the projection distance of the second projection optical system 30B is the second projection distance D2, the second projection distance D2 is three times or more the first projection distance D1. Specifically, the second projection distance D2 is 3.85 times the first projection distance D1. Therefore, the projector 1 of this example can project an enlarged image onto two screens with significantly different projection distances by selectively changing the first projection optical system 30A and the second projection optical system 30B.

[0054] In this example, if the half angle of view of the first projection optical system 30A is defined as the first angle of view and the half angle of view of the second projection optical system 30B is defined as the second angle of view, the first angle of view is three times or more the second angle of view. Specifically, the first angle of view is 3.55 times the second angle of view. Therefore, the projector 1 in this example can significantly change the angle of view during projection by selectively changing the first projection optical system 30A and the second projection optical system 30B.

[0055] In this example, the shift mechanism 41 includes a holder 42 that holds the second optical system 32, a support 43 that supports the holder 42 movably in the Y-axis direction perpendicular to the optical axis N, and a driver 45 that moves the holder 42 to position the projection optical system 30 at the first position 32A or the second position 32B. The controller 4 includes a shift controller 47 that drives and controls the driver 45 to position the projection optical system 30 at the first position 32A or the second position 32B. Therefore, the shift controller 47 can control the movement of the projection optical system 30 to the first position 32A or the second position 32B.

[0056] In this example, the shift mechanism 41 includes a selection unit 46 for selectively disposing the projection optical system 30 at the first position 32A or the second position 32B. When the selection unit 46 selects to dispose the projection optical system 30 at the first position 32A, the shift control unit 47 drives and controls the drive unit 45 to dispose the projection optical system 30 at the first position 32A. Furthermore, when the selection unit 46 selects to dispose the projection optical system 30 at the second position 32B, the shift control unit 47 drives and controls the drive unit 45 to dispose the second optical system 32 at the second position 32B. Therefore, by selecting the position of the projection optical system 30 using the selection unit 46, the user can easily change the second optical system 32 to each position.

[0057] FIG. 7 shows the projection mechanism 3A of the first embodiment. expansion FIG. 8 shows the MTF of the second embodiment. Projection mechanism 3A expansion 7 and 8 show the MTF on the side of the image. The horizontal axis in FIG. 7 and FIG. 8 represents the spatial frequency. The vertical axis represents the contrast reproduction ratio. 3A has high resolution in the first and second forms.

[0058] Example 2 FIG. 9 is a ray diagram that schematically illustrates the entire projection mechanism 3B of Example 2. FIG. 10 is a ray diagram of the projection mechanism 3B in the first mode of Example 2. FIG. 11 is a ray diagram of the projection mechanism 3B in the second mode of Example 2. Note that in FIG. 9, the ray of light from the projection mechanism 3B in the first mode and the ray of light from the projection mechanism 3B in the second mode are superimposed. The projection mechanism 3B of Example 2 differs from the projection mechanism 3A of Example 1 in that it includes a first reflecting member 33. Note that other configurations of the projection mechanism 3B of Example 2 are the same as those of the projection mechanism 3A of Example 1, and therefore, the same reference numerals are used to designate corresponding configurations, and their description will be omitted.

[0059] 9, the projection mechanism 3B includes a first reflecting member 33 disposed on the enlarged side of the first projection optical system 30A and configured to change the projection direction of the first projection optical system 30A. In the first configuration, the projection mechanism 3B deflects the projection direction of the first enlarged image projected from the first optical system 31 using the first reflecting member 33, projecting the first enlarged image onto a first screen S1 located at a first projection position. In the second configuration, the projection mechanism 3B projects the second enlarged image projected from the second optical system 32 onto a second screen S2 located at a second position different from the first position. In this example, the first screen S1 and the second screen S2 intersect, and the first screen S1 is located above the second screen S2 at a position Y1.

[0060] As shown in FIG. 9, the projection mechanism 3B of the first embodiment and the projection mechanism 3B of the second embodiment have different angles of view, and the projection mechanism 3B of the first embodiment is capable of wider-angle projection than the projection mechanism 3B of the second embodiment. In FIG. 9, the light beams reaching each screen S from the projection mechanism 3B of this example are schematically shown as light beams F1 to F4. Light beam F1 is the light beam that reaches the position with the lowest image height. Light beam F4 is the light beam that reaches the position with the highest image height. Light beams F2 and F3 are light beams that reach positions between light beams F1 and F4. Also, as shown in FIG. 9, the first projection distance of the projection mechanism 3B of the first embodiment is shorter than the second projection distance of the projection mechanism 3B of the second embodiment.

[0061] (First embodiment of Example 2) As shown in FIGS. 9 and 10, in the projection mechanism 3B of the first embodiment, the projection optical system 30 is placed at a first position 32A by the shift mechanism.

[0062] The first reflecting member 33 is disposed on the enlargement side of the first optical system 31. The first reflecting member 33 is disposed above the optical axis N of the projection optical system 30 in a first direction Z1 from the first optical system 31. The first reflecting member 33 is made of a plane mirror. The first reflecting member 33 is inclined downward in the second direction Z2.

[0063] 10, when the projection optical system 30 is at the first position 32A, the optical axis N1 of the projection optical system 30 is located above Y1 the liquid crystal panel 18. In other words, the liquid crystal panel 18 is located below Y2 the optical axis N1 of the projection optical system 30.

[0064] As shown in FIGS. 9 and 10 , light rays emitted from the liquid crystal panel 18 pass through the second optical system 32 and then travel upward in the direction Y1 along the optical axis N1. Light rays emitted from the second optical system 32 pass through the first optical system 31 and then travel upward in the direction Y1. The light rays emitted from the first optical system 31 are reflected upward in the direction Y1 and the second direction Z2 by the first reflecting member 33. The light rays whose projection direction is deflected by the first reflecting member 33 are enlarged and projected upward in the direction Y1 and the second direction Z2 and reach the first screen S1. That is, the projection mechanism 3B projects a first enlarged image onto the first screen S1 by passing the projection image light through the first projection optical system 30A, which is composed of the second optical system 32 and the first optical system 31, and the first reflecting member 33.

[0065] (Second embodiment of the second embodiment) As shown in FIGS. 9 and 11, in the projection mechanism 3B of the second embodiment, the projection optical system 30 is placed at a second position 32B by the shift mechanism.

[0066] 11, when the projection optical system 30 is at the second position 32B, the optical axis N2 of the projection optical system 30 is located at a point Y2 below the liquid crystal panel 18. In other words, the liquid crystal panel 18 is located at a point Y1 above the optical axis N2 of the projection optical system 30.

[0067] 9 and 11, the light beam emitted from the liquid crystal panel 18 passes through the second optical system 32, is enlarged and projected downward Y2 along the optical axis N2, and reaches the second screen S2. That is, the projection mechanism 3B passes the projection image light through the second projection optical system 30B, which is composed only of the second optical system 32, and projects a second enlarged image onto the second screen S2 at a different angle of view from the angle of view of the first projection optical system 30A.

[0068] (Action and effect) In the projector 1 of this example, the projection mechanism 3B includes a first reflecting member 33 that is disposed on the enlargement side of the first projection optical system 30A and changes the projection direction of the first projection optical system 30A. Therefore, the projector 1 of this example can change the position of the first screen S1 by the first reflecting member 33. Furthermore, the projector 1 of this example has the same configuration as the projector 1 of Example 1 except that the projection mechanism 3B includes the first reflecting member 33, and therefore can obtain the same effects as the projector 1 of Example 1.

[0069] Example 3 FIG. 12 is a ray diagram that schematically illustrates the entire projection mechanism 3C of Example 3. FIG. 13 is a ray diagram for the projection mechanism 3C in the first embodiment of Example 3. FIG. 14 is a ray diagram for the projection mechanism 3C in the second embodiment of Example 3. Note that in FIG. 12, the ray of light for the projection mechanism 3C in the first embodiment and the ray of light for the projection mechanism 3C in the second embodiment are superimposed. The projection mechanism 3C of Example 3 differs from the projection mechanism 3A of Example 1 in that it includes a second reflecting member 34. Note that other configurations of the projection mechanism 3C of Example 3 are the same as those of the projection mechanism 3A of Example 1, and therefore, the same reference numerals are used for corresponding configurations, and their description will be omitted.

[0070] 12, the projection mechanism 3C includes a second reflecting member 34 that is disposed on the enlarged side of the second projection optical system 30B and that changes the projection direction of the second projection optical system 30B. In the first configuration, the projection mechanism 3C projects a first enlarged image projected from the first optical system 31 onto a first screen S1 located at a first projection position, and in the second configuration, the projection mechanism 3C deflects the projection direction of a second enlarged image projected from the second optical system 32 using the second reflecting member 34, and projects the second enlarged image onto a second screen S2 located at a second position different from the first position. In this example, the first screen S1 and the second screen S2 are perpendicular to each other, and the first screen S1 is located below the second screen S2 at a position Y2.

[0071] As shown in FIG. 12, the projection mechanism 3C of the first embodiment and the projection mechanism 3C of the second embodiment have different angles of view, and the projection mechanism 3C of the first embodiment is capable of wider-angle projection than the projection mechanism 3C of the second embodiment. In FIG. 12, the light beams reaching each screen S from the projection mechanism 3C of this example are schematically shown as light beams F1 to F4. Light beam F1 is the light beam that reaches the position with the lowest image height. Light beam F4 is the light beam that reaches the position with the highest image height. Light beams F2 and F3 are light beams that reach positions between light beams F1 and F4. Also, as shown in FIG. 12, the first projection distance of the projection mechanism 3C of the first embodiment is shorter than the second projection distance of the projection mechanism 3C of the second embodiment.

[0072] (First embodiment of the third embodiment) As shown in FIGS. 12 and 13, in a projection mechanism 3C of the first embodiment, the projection optical system 30 is placed at a first position 32A by a shift mechanism.

[0073] 13, when the projection optical system 30 is at the first position 32A, the optical axis N1 of the projection optical system 30 is located above Y1 the liquid crystal panel 18. In other words, the liquid crystal panel 18 is located below Y2 the optical axis N1 of the projection optical system 30.

[0074] 12 and 13, the light beam emitted from the liquid crystal panel 18 passes through the second optical system 32 and then travels upward Y1 along the optical axis N1. The light beam emitted from the second optical system 32 passes through the first optical system 31 and is then enlarged and projected upward Y1 to reach the first screen S1. That is, the projection mechanism 3C projects the first enlarged image onto the first screen S1 by passing the projection image light through the first projection optical system 30A, which is made up of the second optical system 32 and the first optical system 31.

[0075] (Second embodiment of the third embodiment) As shown in FIGS. 12 and 14, the projection mechanism 3C of the second embodiment is placed at the second position 32B by the shift mechanism.

[0076] The second reflecting member 34 is disposed below the optical axis N of the projection optical system 30 at a position Y2, and in the first direction Z1 from the first optical system 31. The second reflecting member 34 is made of a plane mirror. The second reflecting member 34 is inclined downward Y2 as it extends in the second direction Z2.

[0077] 14, when the projection optical system 30 is at the second position 32B, the optical axis N2 of the projection optical system 30 is located at a point Y2 below the liquid crystal panel 18. In other words, the liquid crystal panel 18 is located at a point Y1 above the optical axis N2 of the projection optical system 30.

[0078] 12 and 14, the light beam emitted from the liquid crystal panel 18 passes through the second optical system 32 and then travels downward along the optical axis N2 in the direction Y2. The light beam emitted from the second optical system 32 is reflected upward in the direction Y1 and the second direction Z2 by the second reflecting member 34. The light beam deflected by the second reflecting member 34 is enlarged and projected upward in the direction Y1 and the second direction Z2, and reaches the second screen S2. That is, the projection mechanism 3C projects the projected image light through the second projection optical system 30B, which is composed only of the second optical system 32, and the second reflecting member 34, to project a second enlarged image onto the second screen S2 at a different angle of view from the angle of view of the first projection optical system 30A.

[0079] (Action and effect) In the projector 1 of this example, the projection mechanism 3C includes a second reflecting member 34 that is disposed on the enlargement side of the second projection optical system 30B and changes the projection direction of the second projection optical system 30B. Therefore, the projector 1 of this example can change the position of the second screen S2 by using the second reflecting member 34. Furthermore, the projector 1 of this example has the same configuration as the projector 1 of Example 1 except that the projection mechanism 3C includes the second reflecting member 34, and therefore can obtain the same effects as the projector 1 of Example 1.

[0080] (Other embodiments) In the above embodiment, when the second optical system 32 is moved by the shift mechanism 41, the first optical system 31 moves integrally with the second optical system 32. However, the first optical system 31 may be fixed. In this case, the holder 42 holds only the second optical system 32. The shift mechanism 41 moves only the second optical system 32 relative to the liquid crystal panel 18 in a direction perpendicular to the optical axis N of the second optical system 32. Furthermore, when the second optical system 32 is in the first position 32A, the optical axis of the first optical system 31 coincides with the optical axis N of the second optical system 32, and when the second optical system 32 is in the second position 32B, the optical axis of the first optical system 31 does not coincide with the optical axis N of the second optical system 32. In this manner, the shift mechanism 41 moves only the second optical system 32, which simplifies the configuration compared to when both the first optical system 31 and the second optical system 32 are moved.

[0081] The drive mechanism 44 may also be configured to manually move the holding portion 42 .

[0082] Furthermore, the projection mechanism 3 may be configured to include both the first reflecting member 33 and the second reflecting member 34. Furthermore, the first reflecting member 33 and the second reflecting member 34 may be mirrors having curved surfaces such as concave or convex surfaces. [Explanation of symbols]

[0083] 1...projector, 2...image forming unit, 3, 3A, 3B, 3C...projection mechanism, 4...control unit, 6...image processing unit, 7...display driving unit, 10...light source, 11...integrator lens, 12...integrator lens, 13...polarization conversion element, 14...superimposing lens, 15...dichroic mirror, 16...reflection mirror, 17R...field lens, 17G...field lens, 17B...field lens, 18, 18B, 18R, 18G...liquid crystal panel, 19...cross dichroic prism, 21...dichroic mirror, 2 2...relay lens, 23...reflecting mirror, 24...relay lens, 25...reflecting mirror, 30...projection optical system, 30A...first projection optical system, 30B...second projection optical system, 31...first optical system, 32...second optical system, 33...first reflecting member, 34...second reflecting member, 41...shift mechanism, 42...holding portion, 43...supporting portion, 44...driving mechanism, 45...driving portion, 46...selecting portion, 47...shift control portion, 51...aperture, L11 to L13...lenses, L21 to L24...lenses, N...optical axis, S...screen, S1...first screen, S2...second screen.

Claims

1. a light modulation element for forming a projected image; a projection mechanism for enlarging and projecting the projection image light of the projection image emitted from the light modulation element, the projection mechanism includes a first optical system, a second optical system located between the first optical system and the light modulation element, and a shift mechanism that moves the second optical system relative to the light modulation element; the shift mechanism moves the second optical system between a first position and a second position different from the first position in a direction perpendicular to an optical axis of the second optical system; When the second optical system is at the first position, the projection mechanism projects a first enlarged image of the projection image at a first projection position by passing the projection image light through a first projection optical system consisting of the second optical system and the first optical system; A projector characterized in that, when the second optical system is in a second position, the projection mechanism passes the projection image light through a second projection optical system consisting only of the second optical system, and projects a second enlarged image of the projection image at a second projection position different from the first projection position at an angle of view different from the angle of view of the first projection optical system.

2. 2. The projector according to claim 1, wherein when the second optical system is moved by the shift mechanism, the first optical system moves integrally with the second optical system.

3. The projector according to claim 1 , wherein the first optical system is fixed.

4. A projector described in any one of claims 1 to 3, characterized in that when the projection distance of the first projection optical system is defined as a first projection distance and the projection distance of the second projection optical system is defined as a second projection distance, the second projection distance is three times or more the first projection distance.

5. A projector described in any one of claims 1 to 4, characterized in that when the half angle of view of the first projection optical system is defined as a first angle of view and the half angle of view of the second projection optical system is defined as a second angle of view, the first angle of view is three times or more the second angle of view.

6. 6. The projector according to claim 1, wherein the projection mechanism includes a first reflecting member disposed on the enlarged side of the first projection optical system and configured to change the projection direction of the first projection optical system.

7. 7. The projector according to claim 1, wherein the projection mechanism includes a second reflecting member disposed on the enlarged side of the second projection optical system to change the projection direction of the second projection optical system.

8. A control unit is provided. the shift mechanism includes a holding unit that holds the second optical system, a support unit that supports the holding unit so that the holding unit is movable in a direction perpendicular to the optical axis, and a drive unit that moves the holding unit to place the second optical system at the first position or the second position, 8. The projector according to claim 1, wherein the control unit includes a shift control unit that controls the drive unit to position the second optical system at the first position or the second position.

9. the shift mechanism includes a selection unit for selectively placing the second optical system at the first position or the second position, when the selection unit selects to place the second optical system at the first position, the shift control unit controls the drive unit to place the second optical system at the first position; 9. The projector according to claim 8, wherein when the selection unit selects to place the second optical system at the second position, the drive unit is driven and controlled to place the second optical system at the second position.

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