JP2017016106A - Optical path change apparatus and projection type video display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical path change apparatus capable of moving an image to a projection surface in two orthogonal directions and projecting the image onto the projection surface with a minimum necessary number of control members.SOLUTION: Points of actuation of actuators 101A, 101B, and 101C are disposed at respective positions of vertexes A, B, and C of a triangle ABC drawn virtually on a plane in parallel to a parallel flat surface of a parallel flat glass 108, and the respective actuators drive the parallel flat glass 108 to be movable forward and backward in a normal direction at the points of the vertexes A, B, and C. From a viewpoint in the normal direction, a center of gravity O of the parallel flat glass 108 is contained inside of the virtually drawn triangle ABC.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an optical path changing device for moving a projection position of an image, and a projection image display device using the same.

  Japanese Patent Laid-Open No. 2004-228561 supports four pieces of parallel flat glass between four corners of a flat plate glass between a fixed pixel type display element that performs light modulation of an image and a quadrangular parallel flat glass that moves a pixel position of a projected image. A pixel position moving apparatus having a structure including the piezoelectric element is disclosed. In this pixel position moving device, it is necessary to use four piezoelectric elements and to control the four piezoelectric elements asymmetrically in order to perform pixel movement.

JP 2007-206567 A

  The present disclosure provides an optical path change that enables simple control and rotation of an optical member for moving the projection position of an image (pixel) about two rotation axes that are orthogonal to each other by three actuators. An apparatus and a projection display apparatus using the same are provided.

  The optical path changing device of the present disclosure includes an optical member having a parallel plate surface for changing an optical path, and a first actuator, a second actuator, and a third actuator. The first actuator, the second actuator, and the third actuator are respectively connected to the optical member with three vertex positions of a triangle virtually drawn on a plane parallel to the parallel plate surface of the optical member as action points. The three vertex positions are driven so as to freely advance and retract in the normal direction of the parallel flat plate surface. When viewed from the normal direction, the center of gravity of the optical member is included inside the triangle.

  According to the present disclosure, it is possible to project an image by moving the image in two directions orthogonal to each other using three actuators.

1 is an external perspective view of an optical path changing device according to Embodiment 1. FIG. Plan view of optical path changing apparatus according to Embodiment 1 Schematic diagram of a voice coil motor used as an actuator of an optical path changing device according to the present disclosure The block diagram which shows the structure of the optical path change apparatus which concerns on this indication The figure for demonstrating the principle of the optical path change by the inclination operation | movement of the parallel plate glass which concerns on this indication The figure for demonstrating the inclination operation | movement of the parallel plate glass which concerns on Embodiment 1. FIG. The figure which shows the rotating shaft of the parallel plate glass which concerns on this indication The figure for demonstrating the principle of the optical path change and pixel shift of input image light by the inclination operation | movement of the parallel plate glass concerning this indication Plan view of an optical path changing apparatus according to Embodiment 2 The figure for demonstrating the inclination operation | movement of the parallel plate glass which concerns on Embodiment 2. FIG. The figure which shows the structure of the projection type video display apparatus concerning this indication

  Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of already well-known matters and repeated descriptions for substantially the same configuration may be omitted. This is to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

  The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment 1)
(Constitution)
FIG. 1 is a perspective view showing a structure of an optical path changing device 100 for driving an optical member in the present embodiment. FIG. 2 is a plan view of the optical path changing device 100.

  As shown in FIG. 1, the optical path changing apparatus 100 includes a circular parallel flat glass 108 that is an optical member, three actuators 101A, 101B, and 101C that drive the actuator, and each of the actuators 101A, 101B, and 101C. And connecting members 106a, 106b, 106c connected to the parallel flat glass 108. The end of the circular parallel flat glass 108 is connected to the movable parts 107a, 107b, and 107c of the actuators 101A, 101B, and 101C by connecting members 106a, 106b, and 106c, and the actuators 101A, 101B, and 101C are connected to each other. The parallel flat glass 108 is supported. In this case, the movable portions 107a, 107b, and 107c of the actuators 101A, 101B, and 101C are power points, and the connection points between the ends of the circular parallel flat glass 108 and the connection members 106a, 106b, and 106c are the action points. . Position sensors 102a, 102b, and 102c for detecting the position are attached to the movable portions 107a, 107b, and 107c, respectively.

  As shown in FIGS. 1 and 2, the connecting members 106 a to 106 c to which the movable portion 107 of the actuator 101 is connected are connected to the outer periphery of the parallel flat glass 108. It is possible to draw a virtual triangle ABC having three connection points as vertices A, B, and C. The triangle ABC is substantially parallel to the parallel plate surface of the parallel plate glass 108. The actuators 101A, 101B, and 101C drive the parallel flat glass 108 at the vertices A, B, and C so as to freely advance and retract in the normal direction. The center of gravity O of the parallel flat glass 108 is included inside the triangle ABC that is virtually drawn when viewed from the normal direction.

  When two rotation axes (horizontal X axis and vertical Y axis) that pass through the center of gravity O and are orthogonal to each other are set on the parallel plate surface of the parallel plate glass 108 or a plane parallel to the parallel plate surface, the vertex A of the triangle ABC is set. And the vertex C are arranged at positions symmetrical with respect to the X axis corresponding to the horizontal (horizontal) direction of the screen surface on which the image light transmitted through the parallel flat glass 108 is projected. A straight line connecting the vertex A and the vertex C of the triangle ABC is arranged in parallel to the Y axis. Further, when the XY plane is a screen surface on which image light transmitted through the parallel flat glass 108 is projected, a straight line connecting the vertex A and the vertex C of the triangle ABC corresponds to the vertical (vertical) direction of the screen. It is parallel to the Y axis which is the rotation axis. Here, the normal direction of the parallel flat glass 108 is perpendicular to the XY plane when the plane of the triangle ABC exists on a plane (XY plane) including the X axis and the Y axis in FIG. Direction. In FIG. 2, points YU and YD are intersections of the outer periphery of the parallel flat glass 108 and the Y axis, and points XR and XL are intersections of the outer periphery of the parallel flat glass 108 and the X axis.

  In this embodiment, a voice coil motor (VCM) is used as the actuators 101A to 101C. FIG. 3 shows an example of the structure of a voice coil motor used as the actuator 101, in which permanent magnets with different magnetic poles (N-pole permanent magnet 1012 and S-pole permanent magnet 1013) are arranged at a constant distance inside the yoke 1011. Arranged to face each other. The movable part 107 is arranged between the permanent magnets 1012, 1013 arranged opposite to each other.

  A guide window 1070 is opened in the movable portion 107, and the yoke 1011 is inserted through the guide window 1070. The movable portion 107 is provided with a coil 1014, and the coil 1014 is disposed between the permanent magnets 1012 and 1013 arranged to face each other. When a drive signal current is passed through the coil 1014, the movable portion 107 moves in the direction of the arrow (uniaxial direction). The movable portion 107 moves in the positive direction or the negative direction from the reference position, with the amount of movement changing according to the magnitude of the signal current flowing through the coil 1014. The amount of movement of the movable portion 107 is detected by the position detection circuits 103a to 103c shown in FIG. 4 based on a signal from the position sensor 102 attached to the movable portion 107. There is a slight gap between the movable portion 107 to which the coil 1014 is attached and the permanent magnets 1012 and 1013. Therefore, when a force in a direction perpendicular to the uniaxial direction driven by the drive signal current is applied, the movable portion 107 is displaced by a permissible distance by the slight gap. In the voice coil motor, the moment can be reduced by fixing a magnet having a large mass and using a lightweight coil on the movable portion side.

  FIG. 4 is a block diagram illustrating a configuration of a drive unit that drives the optical path changing device 100. The three actuators 101A, 101B, and 101C are driven by the drive circuits 104a, 104b, and 104c shown in FIG. The drive circuits 104a to 104c are controlled in accordance with a control signal from one microcomputer 105. The actuators 101A to 101C are driven by the drive signal currents from the drive circuits 104a to 104c so that the movable portions 107a to 107c advance and retreat in one axis direction (direction parallel to the optical axis). The positions of the movable parts 107a to 107c are detected by the position detection circuits 103a to 103c based on signals from the position sensors 102a to 102c provided in the movable parts 107a to 107c. The position detection circuits 103a to 103c amplify signals from the position sensors 102a to 102c with a predetermined gain to generate detection signals. Detection signals from the position detection circuits 103 a to 103 c are input to the microcomputer 105. The microcomputer 105 constantly monitors the positions (or movement amounts) of the movable portions 107a to 107c of the actuators 101A to 101C based on this detection signal, and servo-controls the actuators 101A to 101C.

(Operation)
The operation of the optical path changing apparatus 100 configured as described above will be described below.

  FIG. 5 is a diagram for explaining the principle that the optical path is changed by the inclination of the parallel flat glass 108. When the main surface of the parallel flat glass 108 is orthogonal to the input light beam Li as shown by the solid line in FIG. 5, the input light beam Li travels straight and parallel without being refracted on the incident surface of the parallel flat glass glass 108. It passes through the flat glass 108. Since the light beam and the light exit surface are orthogonal to each other on the exit surface of the parallel flat glass 108, the input light beam Li travels straight without being refracted. For this reason, when the input light beam Li is video light, the image (pixel) does not move.

  On the other hand, when the parallel plate glass 108 is not orthogonal to the input light beam Li as shown by the broken line in FIG. 5, the input light beam Li is refracted at the incident surface of the parallel plate glass 108 and then the parallel plate glass 108. It goes straight inside and refracts and exits at the exit surface.

  The angle of refraction when entering the parallel flat glass 108 is equal to the angle of refraction when exiting from the parallel flat glass 108. For this reason, when the input light beam Li is image light, the image light of the output light beam Lo moves in parallel according to the inclination of the parallel flat glass 108. As a result, the display position of the image output from the parallel flat glass 108 and projected is moved.

  FIG. 6 is a diagram for explaining the principle of the method of inclining the parallel flat glass 108. 6A shows a state in which the parallel flat glass 108 is orthogonal to the optical axis of the image light, FIG. 6B shows a state in which the parallel flat glass 108 is inclined with the X axis as the rotation axis, and FIG. The parallel flat glass 108 is shown tilted about the Y axis as the rotation axis.

  From the state shown in FIG. 6A, for example, the movable portion 107a of the actuator 101A is displaced downward, the actuator 101B and the actuator 101C are synchronized, and the parallel flat glass 108 is moved upward by a displacement corresponding to the displacement of the actuator 101A. Displace to. Accordingly, the parallel flat glass 108 can be displaced as shown in FIG. 6B with the X axis as the rotation axis. Also in the case of displacement with the Y axis as the rotation axis, the movable portions 107a and 107c of the actuator 101A and the actuator 101C are displaced downward, and the actuator 101B is displaced upward. As a result, the Y axis can be displaced as shown in FIG. That is, the parallel flat glass 108 can be tilted by displacing the actuators 101 arranged with the X axis or the Y axis interposed therebetween in opposite directions.

  Utilizing such a principle, the parallel flat glass 108 can be tilted by the actuators 101A to 101C, whereby the input image light can be projected to a plurality of different positions.

  7 and 8 are diagrams for explaining the control of the actuators 101A to 101C for tilting the parallel flat glass 108. FIG.

  As shown in FIG. 7, the X axis and the Y axis intersect at the surface center on the same plane. The center of the plane substantially coincides with the center of gravity O of the parallel flat glass 108. In a state where the center of the surface is maintained at a fixed position, the display position of the pixel can be moved two-dimensionally by tilting the parallel flat glass 108 by tilting the X axis and the Y axis. The operation of the actuators 101A to 101C for moving the display position of the pixel will be described with reference to FIG.

  FIG. 8 is a diagram for explaining the operation of the actuators 101A to 101C for moving the display position of the pixel. (A)-(d) of FIG. 8 is a figure for demonstrating the control state of the parallel plate glass 108. FIG. FIG. 8E is a diagram showing the display position of the pixel that moves with the inclination of the parallel flat glass 108.

  In FIG. 8, a broken line arrow indicates an output light beam Lo when the input light beam Li is perpendicularly incident on the parallel plate glass 108, that is, when the parallel plate glass 108 is in a horizontal position. In this case, if the input light beam Li is image light, the output light beam Lo is displayed as a pixel at a position “f” shown in FIG. Hereinafter, this state is referred to as a “reference state”. By driving each of the actuators 101A to 101C, the parallel flat glass 108 can be tilted, and the display position of the pixel can be shifted to the positions “a” to “d”.

  In FIG. 8, the points XR, XL, YU, and YD are the intersections of the outer periphery of the parallel flat glass 108 shown in FIG. 2, the X axis, and the Y axis, respectively.

  The position “a” shown in FIG. 8E is the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (first state) shown in FIG. Indicates. That is, in the first state, as shown in FIG. 8A-1, the YU point is moved downward by the actuator 101A, and the YD point is moved upward by the actuator 101B and the actuator 101C by the same amount as the displacement amount of the YU point. Just move. Along with this movement, as shown in FIG. 8A-2, the XL point is moved downward by the actuator 101B, and the XL point is moved upward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Thereby, a pixel can be displayed at the position “a” shown in FIG.

  The position “b” shown in FIG. 8E is the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (second state) shown in FIG. 8B. Indicates. That is, in the second state, as shown in FIG. 8B-1, the YU point is moved upward by the actuator 101A, and the YD point is moved downward by the actuator 101B and the actuator 101C by the same amount as the displacement amount of the YU point. Just move. Along with this movement, as shown in FIG. 8B-2, the XL point is moved downward by the actuator 101B, and the XR point is moved upward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Thereby, a pixel can be displayed at the position “b” shown in FIG.

  The position “c” shown in FIG. 8E is the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (third state) shown in FIG. 8C. Indicates. That is, in the third state, as shown in FIG. 8C-1, the YU point is moved upward by the actuator 101A, and the YD point is moved downward by the actuator 101B and the actuator 101C by the same amount as the displacement amount of the YU point. Just move. Along with this movement, as shown in FIG. 8C-2, the XL point is moved upward by the actuator 101B, and the XL point is moved downward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Thereby, a pixel can be displayed at the position “c” shown in FIG.

  The position “d” shown in FIG. 8E is the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (fourth state) shown in FIG. 8D. Indicates. That is, in the fourth state, as shown in FIG. 8D-1, the YU point is moved downward by the actuator 101A, and the YD point is moved upward by the actuator 101B and the actuator 101C by the same amount as the displacement amount of the YU point. Just move. Along with this movement, as shown in FIG. 8 (d-2), the XL point is moved upward by the actuator 101B, and the XL point is moved downward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Put it in a state. Thereby, a pixel can be displayed at the position “d” shown in FIG.

  By inputting the image light to the parallel flat glass at the timing when the first to fourth states shown in (a) to (d) of FIG. 8 are reached, four different positions “a” shown in (e) of FIG. "-" D "can display pixels.

(Effect etc.)
The optical path changing apparatus 100 according to the present embodiment includes parallel flat glass 108 for changing an optical path, and actuators 101A to 101C having movable parts 107a to 107c that are controlled to move in one axis direction by a drive signal. The connecting members 106a to 106c connect the end portion of the parallel flat glass 108 and the movable portions 107a to 107c of the actuator. The center of gravity O of the parallel flat glass 108 is positioned inside the triangle ABC having apexes A, B, and C as connection points between the connecting members 106 a to 106 c and the end of the parallel flat glass 108. The position detection circuits 103a to 103c detect the movement amounts of the movable parts 107a to 107c of the actuators 101A to 101C from the position sensors 102a to 102c and output detection signals. The microcomputer 105 controls the movement of the movable parts 107a to 107c of the actuators 101A to 101C based on this detection signal.

  With this configuration, by controlling the amount of displacement of the movable parts 107a to 107c in combination with the actuator, it is possible to control the tilt of the parallel flat glass 108 using two orthogonal axes (X axis and Y axis) as rotation axes. It becomes. Thus, by applying a signal for controlling the movement amount of the movable portions 107a to 107c to the three actuators 101A to 101C, the horizontal and vertical movement of the projected image can be realized. Therefore, it is possible to realize an optical path changing device that can easily control the direction of movement of the image display position.

(Embodiment 2)
The optical path changing device disclosed in the second embodiment is different from the first embodiment in the arrangement and operation of the actuators 101A to 101C. Therefore, in the second embodiment, this difference will be described, and a description overlapping that of the first embodiment will be omitted.

  FIG. 9 shows the arrangement of the actuators 101A to 101C of the optical path changing device 110 disclosed in the second embodiment.

  The connecting members 106a to 106c to which the movable portions 107a to 107c of the actuators 101A to 101C are coupled are vertices A, B, and C of an isosceles triangle ABC virtually drawn on the outer periphery of the parallel flat glass 108 as shown in FIG. It is connected to the position. The center of gravity O of the parallel flat glass 108 is disposed inside the isosceles triangle ABC. In addition, when two rotation axes (X axis and Y axis) orthogonal to each other through the center of gravity O of the parallel flat glass are set, the vertex B (second vertex) shared by the two equilateral sides of the isosceles triangle ABC is Arranged on the X-axis. This apex B is at the same position as the XL point that is the intersection of the outer periphery of the circular parallel flat glass 108 and the X axis, and the connecting member 106b connected to the actuator 101B (second actuator) is connected to the apex B. Be placed.

  A connecting member 106a connected to the actuator 101A (first actuator) is disposed at the vertex A of the isosceles triangle ABC. In addition, a connecting member 106c connected to the actuator 101C (third actuator) is disposed at the vertex C of the isosceles triangle ABC. At this time, a straight line (base AC) connecting the vertex A and the vertex C is parallel to a rotation axis (Y axis in FIG. 9) different from the rotation axis where the vertex B is arranged. In addition, the vertexes A to C to which the coupling members 106a to 106c are coupled serve as the action points of the actuators 101A to 101C, and the actuators 101A to 101C have the parallel flat glass 108 at the vertexes A to C in the normal direction of the parallel flat plate surface. Drive forward and backward.

  The actuator 101A and the actuator 101C drive around the X axis (first rotation axis, in the example of FIG. 9, the symmetry axis and the X axis are coaxial) that is parallel to the symmetry axis of the isosceles triangle ABC. . Driving around the Y axis (second rotation axis) orthogonal to the X axis is performed by the actuators 101A to 101C.

  FIG. 10 is a diagram for explaining the principle of the method of inclining the parallel flat glass 108. 10A shows a state in which the parallel flat glass 108 is orthogonal to the optical axis of the image light, FIG. 10B shows a state in which the parallel flat glass 108 is inclined with the X axis as the rotation axis, and FIG. The parallel flat glass 108 is shown tilted about the Y axis as the rotation axis.

  From the state shown in FIG. 10A, for example, the movable portion 107b of the actuator 101B is not displaced, the movable portion 107a of the actuator 101A is displaced downward, and the movable portion 107c of the actuator 101C is moved from the state shown in FIG. It is displaced upward by the same displacement amount as that of the movable portion 107a. Accordingly, the parallel flat glass 108 can be inclined as shown in FIG. 10B with the X axis as the rotation axis. Further, as shown in FIG. 10C, the movable portion 107b of the actuator 101B is displaced upward, the actuator 101A and the actuator 101C are synchronized, and the displacement amount at the point XR shown in FIG. 9 becomes the same displacement amount as the point XL. It is displaced downward so that it becomes. Thereby, the parallel flat glass 108 can be inclined with the Y axis as the rotation axis. That is, the parallel flat glass 108 can be tilted by displacing the actuators 101 arranged with the X axis or the Y axis interposed therebetween in opposite directions.

  The operation of the actuators 101A to 101C for moving the display position of the pixel will be described with reference to FIG. 8 described in the first embodiment.

  Similarly to the case described in the first embodiment, each of the actuators 101A to 101C is driven to incline the parallel flat glass 108, and the display positions of the pixels shown in FIG. d ".

  In FIG. 8, the points XR, XL, YU, and YD are the intersections of the outer periphery of the parallel flat glass 108 shown in FIG. 9, the X axis, and the Y axis.

  The position “a” shown in FIG. 8E indicates the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (first state) as shown in FIG. Show. That is, in the first state, as shown in FIG. 8A-1, the YU point is moved downward by the actuator 101A, and the YD point is moved upward by the actuator 101C by the same amount as the displacement of the YU point. . Along with this movement, as shown in FIG. 8 (a-2), the XL point is moved downward by the actuator 101B, and the XL point is moved upward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Put it in a state. Therefore, the actuator 101A and the actuator 101C move the displacement amount obtained by adding the displacement amount by the control around the X axis and the displacement amount by the control around the Y axis. Thereby, a pixel can be displayed at the position “a” shown in FIG.

  The position “b” shown in FIG. 8E indicates the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (second state) as shown in FIG. 8B. Show. That is, in the second state, as shown in FIG. 8B-1, the YU point is moved upward by the actuator 101A, and the YD point is moved downward by the actuator 101C by the same amount as the displacement of the YU point. . Along with this movement, as shown in FIG. 8B-2, the XL point is moved downward by the actuator 101B, and the XL point is moved upward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Put it in a state. Thereby, a pixel can be displayed at the position “b” shown in FIG.

  The position “c” shown in FIG. 8E indicates the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (third state) as shown in FIG. 8C. Show. That is, in the third state, as shown in FIG. 8C-1, the YU point is moved upward by the actuator 101A, and the YD point is moved downward by the actuator 101C by the same amount as the displacement of the YU point. . Along with this movement, as shown in FIG. 8 (c-2), the XL point is moved upward by the actuator 101B, and the XL point is moved downward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Put it in a state. Thereby, a pixel can be displayed at the position “c” shown in FIG.

  The position “d” shown in FIG. 8E indicates the position of the pixel displayed on the projection plane when the parallel flat glass 108 is in the state (fourth state) as shown in FIG. 8D. Show. That is, in the fourth state, as shown in FIG. 8D-1, the YU point is moved downward by the actuator 101A, and the YD point is moved upward by the actuator 101C by the same amount as the displacement of the YU point. . Along with this movement, as shown in FIG. 8 (d-2), the XL point is moved upward by the actuator 101B, and the XL point is moved downward by the same amount as the displacement of the XL point by the actuator 101A and the actuator 101C. Put it in a state. Thereby, a pixel can be displayed at the position “d” shown in FIG.

(Effect etc.)
In the present embodiment, triangles having apexes A, B, and C as the three connection points of the connection members 106a to 106c connected to the parallel flat glass 108 form an isosceles triangle ABC. Then, the three actuators 101A to 101C are arranged such that the vertex (second vertex) shared by the two equilateral sides of the isosceles triangle ABC is located on one of the two rotation axes (X axis, Y axis) orthogonal to each other. Be placed. As a result, the displacement amount of the movable portion is controlled by simpler control than in the first embodiment, and the tilt control of the parallel flat glass 108 is performed around two axes (X axis and Y axis) orthogonal to each other. Can be done.

  In this embodiment, as shown in FIG. 9, the isosceles triangle ABC is such that the vertex B shared by the two equilaterals is located on the X axis and the vertices A and C are line symmetric with respect to the X axis. Although arranged, the vertex B may be located on the Y axis and the vertexes A and C may be arranged symmetrically with respect to the Y axis. However, since it is necessary to move the pixels in the vertical direction of the screen more accurately than in the horizontal direction, the vertex is symmetrical with respect to the X axis which is the rotation axis of the parallel flat glass 108 for moving the pixels in the vertical direction. It is desirable to arrange A and C and arrange the vertex B on the X axis.

  Further, in the present embodiment, as shown in FIG. 9, the base AC of the isosceles triangle ABC that defines the action point of the actuator 101 for rotating the parallel flat glass 108 is shorter than the equilateral BA and BC. This is because if the base AC is lengthened, the distance between the base AC and the Y axis becomes too short, and the moment required when the Y axis is used as the rotation axis becomes too large. Conversely, if the base AC is made too short, the distance between the vertices A and C and the X axis becomes too short, and the moment required when the X axis is used as the rotation axis becomes too large. Therefore, in consideration of the moment for rotating the parallel flat glass 108, the distances between the vertices A and C and the X and Y axes are substantially equal, that is, the angle AOC (the line segment OA and the line segment). It is desirable to arrange the vertices A and C so that the angle formed by the OC is 90 degrees.

(Embodiment 3)
The optical path changing device disclosed in the first and second embodiments can be applied to the projection display apparatus 200.

  FIG. 11 is a diagram for describing a configuration of an optical system of the projection display apparatus 200 to which the optical path changing apparatuses 100 and 110 according to the present disclosure are applied. In the following description, an XYZ orthogonal coordinate system is set as shown in FIG.

  First, the illumination optical system 300 of the projection display apparatus 200 will be described. The laser light source is composed of a plurality of blue semiconductor lasers 301 in order to realize a high-luminance illumination device. The laser light emitted from each blue semiconductor laser 301 is collimated by the corresponding collimator lens 302. The light emitted from the collimator lens 302 becomes substantially parallel light, and the entire luminous flux is condensed by the condenser lens 303, passes through the diffuser plate 304, and is converted into substantially parallel light again by the lens 305. The laser beam converted into substantially parallel light by the lens 305 is incident on a dichroic mirror 306 disposed at approximately 45 degrees with respect to the optical axis.

  The diffusion plate 304 is a glass flat plate, and a diffusion surface with fine irregularities is formed on one side. The dichroic mirror 306 has a characteristic of reflecting light in the wavelength region of the blue semiconductor laser 301 and transmitting light in other wavelength regions.

  The laser light incident on the dichroic mirror 306 in the −X direction is reflected by the dichroic mirror 306 and emitted in the −Z direction. Thereafter, the laser light is collected by the condenser lenses 307 and 308 to excite the phosphor formed on the phosphor wheel 320.

  The phosphor wheel 320 is provided with a segment in which a red phosphor and a green phosphor are formed in a circumferential direction on a disk-shaped substrate, and further provided with an opening as a light transmission region.

  Red light and green light obtained from the red phosphor and green phosphor of the phosphor wheel 320 are emitted from the phosphor wheel 320. These red light and green light are substantially collimated by the condenser lenses 308 and 307, pass through the dichroic mirror 306, collected by the condenser lens 317, and enter the rod integrator 318.

  On the other hand, the blue light of the blue semiconductor laser 301 that has passed through the opening of the phosphor wheel 320 travels along the path of the lens 309, the lens 310, the mirror 311, the lens 312, the mirror 313, the lens 314, the mirror 315, and the lens 316, and is dichroic. The light is reflected by the mirror 306, collected by the condenser lens 317, and enters the rod integrator 318. The lenses 312, 314, and 316 function as relay lenses.

  The light emitted from the rod integrator 318 is incident on a total reflection prism 335 including a pair of prisms 333 and 334 through lenses 330, 331, and 332, and a DMD (Digital Mirror Device) 336 that is a light modulation element. Incident light is modulated and emitted as image light. The lenses 330 and 331 have a relay lens, and the lens 332 has a function of causing the light on the exit surface of the rod integrator 318 to form an image on the DMD 336.

  The image light emitted from the DMD 336 enters the optical path changing device 120. As the optical path changing device 120, the optical path changing devices 100 and 110 disclosed in the first and second embodiments can be used. The light transmitted through the optical path changing device 120 enters the projection lens 337, and the light emitted from the projection lens 337 is enlarged and projected on the screen as image light.

  The wobbling display can be performed by the projection display apparatus 200 by using the function of moving the display position of the image light of the optical path changing apparatus 120. Here, the wobbling display is a method of displaying different images while shifting the display position a plurality of times during one frame period of the input image, and equivalently improving the resolution of the display image, and is also called pixel shift display. . The microcomputer 105 shown in FIG. 4 drives the actuator 101 with a control signal synchronized with the driving of the DMD 336.

(Other embodiments)
As described above, Embodiments 1 to 3 have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to embodiments that have been changed, replaced, added, omitted, and the like. Moreover, it is also possible to combine each component demonstrated in the said Embodiment 1-3 and it can also be set as new embodiment. Therefore, other embodiments will be exemplified below.

  In the above-described embodiment, the configuration in which the parallel flat glass that moves the input light beam is held on the outer periphery of the parallel flat glass has been described, but the method for supporting the parallel flat glass is not limited thereto. You may hold | maintain by arrange | positioning a parallel plate glass in a frame and arrange | positioning a connection part with an actuator in the arm part extended from the frame. Further, the parallel plate glass does not need to be circular, and may have any shape as long as there is a plane through which the optical path passes. In the optical path changing device, an example using a transparent plate as an optical element and a voice coil motor as an actuator has been described. However, the optical element is not limited to this, and the optical element may be a lens group, and a piezoelectric element is used as an actuator. It may be used.

  In the above-described embodiment, only the case of driving around two orthogonal axes has been described. However, a driving function with one axis or a switching function between one axis driving and two axis driving may be included. In the case of uniaxial drive, the vertices shared by the two equilateral sides of the isosceles triangle are arranged on the rotation axis, and the actuators arranged at the remaining two vertex positions (arranged symmetrically with respect to the rotation axis). The drive may be executed with

  In the above embodiment, the illumination optical system using a laser light source has been described. However, the present invention is not limited to this, and an illumination optical system using a lamp light source, an LED light source, or the like may be used. The optical path changing device is disposed between the DMD 336 and the projection lens 337, but may be disposed between the DMD 336 and the projection surface, and may be inserted after the projection lens 337, for example.

  The above-described embodiments are for illustrating the technique in the present disclosure, and various modifications, replacements, additions, omissions, and the like can be made within the scope of the claims and their equivalents.

  The present disclosure can be applied to a projection display apparatus such as a projector.

100, 110, 120 Optical path changing device 101, 101A, 101B, 101C Actuator 102, 102a, 102b, 102c Position sensor 103a, 103b, 103c Position detection circuit 104a, 104b, 104c Drive circuit 105 Microcomputer 106a, 106b, 106c Connecting member 107, 107a, 107b, 107c Movable part 108 Parallel flat glass 200 Projection type image display device 300 Illumination optical system 301 Blue semiconductor laser 302 Collimator lens 303, 307, 308, 317 Condensing lens 304 Diffuser plate 305, 309, 310 Lens 306 Dichroic mirror 311, 313, 315 Mirror 312, 314, 316 Lens 318 Rod integrator 320 Phosphor wheel 330, 331 32 lens 333, 334 prism 335 total reflection prism 336 DMD
337 Projection lens

Claims (8)

An optical member having a parallel plate surface for changing the optical path;
Three vertices of a triangle virtually drawn on a plane parallel to the parallel flat plate surface of the optical member are connected to the optical member as operating points, and the three vertex positions are connected to the parallel flat plate surface. A first actuator, a second actuator, and a third actuator, each of which is driven to move forward and backward in the normal direction,
The optical path changing device, wherein the center of gravity of the optical member is included inside the triangle as viewed from the normal direction. The optical member is driven around a first rotation axis and a second rotation axis that are orthogonal to the center of gravity of the optical member and parallel to the parallel plate surface,
The optical path changing device according to claim 1, wherein one side of the triangle is parallel to the second rotation axis.   The optical path changing device according to claim 2, wherein the second rotation axis corresponds to a vertical direction of a screen on which image light transmitted through the optical member is projected.   4. The optical path changing device according to claim 2, wherein two vertices of the triangle are arranged at positions symmetrical with respect to the first rotation axis. 5.   5. The optical path changing device according to claim 4, wherein the first rotation axis corresponds to a horizontal direction of a screen on which image light transmitted through the optical member is projected.   The optical path changing device according to claim 2, wherein the triangle is an isosceles triangle. The second actuator acts on a second vertex shared by two equilateral sides of the isosceles triangle,
The first actuator and the third actuator act on the first vertex and the third vertex, respectively.
The first rotation axis is parallel to the symmetry axis of the isosceles triangle, the first actuator and the third actuator perform driving around the first rotation axis, and the second rotation axis. The optical path changing device according to claim 6, wherein the first actuator, the second actuator, and the third actuator perform rotation driving. A light source;
A light modulation element that modulates light from the light source into video light by a video signal;
A projection optical system for enlarging and projecting the image light;
The optical path changing device according to any one of claims 1 to 7, disposed between the light modulation element and the projection optical system,
Projection-type image display device with

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