JP6624275B2 - Image display device - Google Patents

Description

  The present invention relates to the technical field of an image display device such as a head-up display.

  Conventionally, an image display device such as a head-up display or a laser projector has been proposed. For example, Patent Document 1 discloses a HUD (Head Up Display: Head Up Display) including a display that projects a display image, and a combiner that displays a virtual image by receiving light projected from the display. I have.

  It is preferable that such an image display device displays an image so that the image can be observed at a desired viewpoint position (for example, a viewpoint position at which visibility is good for an observer). That is, it is preferable that such an image display device displays an image so that an observer located at a desired viewpoint position can observe the image. Therefore, the HUD described in Patent Document 1 moves a combiner in order to display an image at a desired viewpoint position.

  In addition to Patent Document 1, Patent Documents 2 to 4 are cited as prior art documents.

JP 2006-062501 A JP-T-2007-517254 WO 2013/153655 pamphlet Patent No. 5075595

  However, in the technology described in Patent Literature 1, the image display device needs to move a relatively large combiner in order to display an image so that the image can be observed at a desired viewpoint position. . For this reason, in the technology described in Patent Literature 1, the image display device needs to newly include a relatively complicated and large-sized drive mechanism for moving the combiner. Therefore, there is a technical problem that the cost and size of the image display device increase.

  The problems to be solved by the present invention include those described above as examples. The present invention provides an image projection apparatus capable of relatively easily displaying an image so that the image can be observed at a desired viewpoint position (for example, a viewpoint position at which visibility is good for an observer). The task is to

In order to solve the above-mentioned problem, an image display device includes: an emitting unit that emits a laser beam; and a laser beam emitted by the emitting unit is regularly arranged along a scanning surface on which the laser beam scans. Diffusing means including a plurality of optical elements for diffusing light, and light formed by the laser light on the scanning surface such that the laser light is diffused in a desired diffusion direction by each of the plurality of optical elements. Adjusting means for adjusting the formation position of the spot with respect to each of the plurality of optical elements. An image displayed by the laser light by changing a formation position of the light spot based on a shift amount that is a shift amount of the light spot with respect to a center of the optical element according to the desired diffusion direction; Adjusts the viewpoint position at which can be observed.

FIG. 2 is a block diagram illustrating a configuration of an image display device according to the present embodiment. FIG. 2 is a plan view showing the screen viewed from a direction (Z-axis direction) along an optical path of laser light, and a cross-sectional view taken along line II-II ′ of the screen. A plan view showing a scanning position detection plate observed from a direction along the optical path of the laser light, showing a positional relationship between a micro lens provided in the screen and a light receiving element provided in the scanning position detection plate, at the center of the lens surface of the micro lens. On the other hand, when the center of the laser spot is shifted along the direction intersecting with the scanning direction of the laser light, and when the laser spot is not shifted, the light receiving element of the laser light transmitted through the micro lens is shown by a micro lens and a light receiving element. FIG. 4 is a cross-sectional view of the element and a graph showing a relationship between a difference signal output from a pair of light receiving elements and a shift amount (shift amount) of the center of the laser spot with respect to the center of the lens surface of the micro lens. FIG. 5 is an explanatory diagram showing a state of diffusion of laser light LB by a screen when a diffusion angle of laser light in each microlens is relatively small and large. FIG. 7 is an explanatory diagram showing a relationship between a shift amount of a forming position of a beam spot along a direction intersecting a scanning direction of a laser beam LB with respect to a center of a lens surface of a microlens and a diffusion direction of a laser beam in each microlens. FIG. 9 is an explanatory diagram showing a beam spot formation position with respect to the center of the lens surface of the microlens when the image display device displays an image observable from a desired viewpoint position. FIG. 9 is an explanatory diagram showing a beam spot formation position with respect to the center of the lens surface of the microlens when the image display device displays an image observable from a desired viewpoint position. FIG. 9 is an explanatory diagram illustrating an example in which images are displayed at a plurality of viewpoint positions. FIG. 9 is an explanatory diagram illustrating an example in which images are displayed at a plurality of viewpoint positions.

  Hereinafter, embodiments of the image display device will be described in order.

<1>
The image display device according to the present embodiment includes: an emission unit that emits a laser beam; and a plurality of emission units that are regularly arranged along a scanning surface on which the laser beam emitted by the emission unit scans and each diffuse the laser beam. A diffusing unit including an optical element, and a light spot formed by the laser light on the scanning surface, such that the laser light is diffused in a desired diffusion direction by each of the plurality of optical elements. Adjusting means for adjusting the formation position of each of the plurality of optical elements.

  According to the image display device of the present embodiment, the emitting unit emits a laser beam. The laser beam is a laser beam used to display an image (in other words, to project or draw). The laser beam emitted from the emission unit is applied to the scanning surface so as to scan the scanning surface of the diffusion unit. The laser beam scans the scanning surface to draw an intermediate image on the scanning surface. The laser light applied to the scanning surface is diffused by each of the plurality of optical elements. The diffused laser light reaches the observer. As a result, the observer can observe an image corresponding to the intermediate image drawn on the scanning surface by the laser light as a virtual image (or as a real image in some cases).

  In the present embodiment, in particular, the adjusting unit can adjust the formation position of the light spot on the scanning surface. More specifically, the adjusting means adjusts the light spot forming position for each of the plurality of optical elements (in other words, the relative positional relationship between each of the plurality of optical elements and the light spot forming position). I do.

  Here, when the formation position of the light spot with respect to each optical element changes, the diffusion direction of the laser light diffused by each optical element changes. When the diffusion direction of the laser light changes, the viewpoint position at which the image displayed by the laser light can be observed changes. Conversely, by adjusting the diffusion direction of the laser light that is diffused by each optical element, an image can be observed at a desired viewpoint position (for example, a viewpoint position where visibility is good for an observer). It is estimated that the image is displayed as follows.

  As described above, the adjustment of the formation position of the light spot on the scanning surface leads to the adjustment of the diffusion direction of the laser light. Further, adjustment of the diffusion direction of the laser light leads to adjustment of a viewpoint position at which an image displayed by the laser light can be observed. Therefore, the adjusting means can adjust the diffusion direction of the laser light by adjusting the position where the light spot is formed on the scanning surface. As a result, the adjusting means can adjust the viewpoint position at which the image displayed by the laser light can be observed. For example, the adjusting unit adjusts the formation position of the light spot on the scanning surface so that the laser light is diffused in a desired diffusion direction by the diffusion unit, so that an image can be observed at a desired viewpoint position. Thus, the viewpoint position at which the image can be observed can be adjusted. As a result, the image display device can display an image so that the image can be observed at a desired viewpoint position (for example, a viewpoint position at which visibility is good for an observer).

<2>
In another aspect of the image display device according to the present embodiment, the adjusting unit diffuses the laser beam in a desired direction by the diffusing unit so that an image displayed by the laser beam has a desired viewpoint position. The position where the light spot is formed is adjusted so that the light spot can be observed.

  According to this aspect, the adjusting unit adjusts the formation position of the light spot on the scanning surface so that the laser light is diffused in the desired diffusion direction by the diffusion unit, so that the image is formed at the desired viewpoint position. The viewpoint position at which the image can be observed can be adjusted so that the image can be observed.

<3>
In another aspect of the image display device according to the present embodiment, the plurality of optical elements are regularly arranged along a scanning direction of the laser light on the scanning surface, and the adjusting unit includes the laser light. The formation position of the light spot is adjusted so that the light spot moves in a direction intersecting the scanning direction of the light spot.

  According to this aspect, the adjusting unit adjusts the formation position of the light spot so that the light spot moves along the direction intersecting the scanning direction of the laser light, so that an image can be observed at a desired viewpoint position. Thus, the viewpoint position at which the image can be observed can be adjusted.

<4>
In another aspect of the image display device of the present embodiment, a viewpoint position at which a first image portion displayed by the laser light diffused by a first optical element of the plurality of optical elements can be observed, A viewpoint position at which a second image portion displayed by the laser light diffused by a second optical element different from the first optical element among the plurality of optical elements can be observed matches or overlaps The position where the light spot is formed is adjusted so that the light spot is formed.

  According to this aspect, the adjustment unit is configured to control the viewpoint position at which the image can be observed so that the image formed by combining the first image portion and the second image portion can be observed at the desired viewpoint position. Can be adjusted.

<5>
In another aspect of the image display device of the present embodiment, a diameter of the light spot is smaller than an arrangement interval between two adjacent optical elements among the plurality of optical elements.

  When the diameter of the light spot is smaller than the interval between the two adjacent optical elements, the adjustment of the formation position of the light spot on the scanning surface is performed by adjusting the diffusion direction of the laser light (further, display by the laser light is performed). (Adjustment of the viewpoint position at which the image to be observed can be observed). Therefore, according to this aspect, the adjusting means adjusts the formation position of the light spot having a diameter smaller than the arrangement interval of the two adjacent optical elements, so that the image displayed by the laser light can be observed. The position can be adjusted.

  Furthermore, according to this aspect, since the diameter of the light spot is relatively small, compared to the case where the diameter of the light spot is not smaller than the arrangement interval between two adjacent optical elements, the light spot is displayed by the laser light. The brightness of the image is increased. As a result, the image display device can display an image having a relatively large luminance so as to be observable at a desired viewpoint position. That is, the image display device can appropriately satisfy both requirements of the luminance of the image and the viewpoint position at which the image can be observed.

<6>
As described above, in another aspect of the image display device in which the diameter of the light spot is smaller than the arrangement interval between two adjacent optical elements, an image displayed by the laser light when the formation position of the light spot is not adjusted is reduced. The diffusion angle of the laser light that can be observed from a predetermined viewpoint position is α, and the diffusion angle of the laser light at which the image can be observed from the predetermined viewpoint position when adjusting the formation position of the light spot is α. Assuming β, the diameter of the light spot is the arrangement interval × β / α.

  According to this aspect, the adjusting unit adjusts the formation position of the light spot having a diameter corresponding to a value obtained by multiplying β / α with the arrangement interval between two adjacent optical elements, The viewpoint position at which the image displayed by the laser light can be observed can be adjusted. Further, the brightness of the image displayed by the laser light becomes α / β times as compared with the case where the diameter of the light spot is not smaller than the arrangement interval between two adjacent optical elements. As a result, the image display device can display an image having a relatively large luminance so as to be observable at a desired viewpoint position.

  The operation and other advantages of the present embodiment will become more apparent from the examples explained below.

  As described above, the image display device according to the present embodiment includes the emission unit, the diffusion unit, and the adjustment unit. Therefore, an image can be displayed relatively easily so that the image can be observed at a desired viewpoint position (for example, a viewpoint position at which visibility is good for an observer).

  Hereinafter, embodiments of the image display device will be described with reference to the drawings. In this embodiment, the description will be given using an example in which the image display device is a head-up display. The head-up display can make a user observe an image as a virtual image. In other words, the head-up display can allow an image to be observed as a virtual image from the position of the user's eyes (a so-called eye point). However, the image display device may be any image display device other than the head-up display (for example, a MEMS display, a projector, or the like).

(1) Configuration of Image Display Device 1 First, the configuration of the image display device 1 of the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram illustrating a configuration of the image display device 1 according to the present embodiment.

  As shown in FIG. 1, the image display device 1 includes a laser light source unit 11 as a specific example of “emission unit”, a condenser lens 13, a MEMS mirror 14 as a specific example of “adjustment unit”, A screen 15, which is a specific example of “diffusion unit”, a scanning position detection plate 16, a combiner 17, and a controller 18 are provided.

  The laser light source unit 11 emits a laser beam LB based on an image signal indicating an image to be displayed by the image display device 1 under the control of a laser controller 181 described later. The laser light source unit 11 emits the laser light LB toward the MEMS mirror 14 via the condenser lens 13.

  Although not shown for simplicity of the drawing, the laser light source unit 11 includes a laser diode that emits red laser light, a laser diode that emits green laser light, and a laser diode that emits blue laser light. May be provided. In this case, it is preferable that the three laser beams emitted from the three laser diodes 111 be combined into one laser beam LB by an optical element included in the laser light source unit 11. As a result, the image display device 1 can display a full-color image.

  The condenser lens 13 is arranged on the optical path of the laser light LB between the laser light source unit 11 and the MEMS scanner 14. The condenser lens 13 condenses the laser light LB emitted by the laser light source unit 11 on the reflection surface of the MEMS scanner 14.

  The MEMS scanner 14 reflects the laser beam LB collected by the condenser lens 13 toward the screen 15. For this reason, the MEMS scanner 14 includes a reflection surface that can reflect the laser beam LB toward the screen 15. The reflection surface included in the MEMS scanner 14 is controlled such that the laser light LB scans the scanning surface 153 (see FIGS. 2A and 2B) of the screen 15 under the control of the MEMS control unit 183 described later. Move around. As a result, the laser beam LB reflected by the MEMS scanner 14 can draw an image (for example, an intermediate image) on the screen 15.

  The screen 15 is a transmission screen through which the laser light LB reflected by the MEMS scanner 14 passes. Here, the configuration of the screen 15 will be described with reference to FIGS. 2 (a) and 2 (b). FIG. 2A is a plan view showing the screen 15 viewed from a direction (Z-axis direction) along the optical path of the laser light LB. FIG. 2B is a cross-sectional view taken along the line II-II ′ of the screen shown in FIG. 2A and 2B, the screen 15 will be described using an XYZ coordinate system including an X axis, a Y axis, and a Z axis that are orthogonal to each other, for convenience of description.

  As shown in FIGS. 2A and 2B, the screen 15 is a plate-shaped member irradiated with the laser light LB (in other words, scanned by the laser light LB1). However, the screen 15 may be a member having a shape (for example, a disk shape) different from the plate shape.

  The screen 15 includes a microlens array 151 in which a plurality of microlenses 152 are arranged. As shown in FIG. 2B, each micro lens 152 diffuses (in other words, disperses) the laser light LB incident on the lens surface of the micro lens 152. Therefore, the microlens array 151 diffuses the laser beam LB at a diffusion angle determined according to the curvature of the microlens 152 constituting the microlens array 151 and the like.

  The microlens array 151 is regularly (in other words, periodically) arranged along the scanning direction (Y-axis direction in FIG. 2) of the laser light LB indicated by the dotted arrow in FIG. A plurality of micro lenses 152 are included. A lens group composed of a plurality of microlenses 152 regularly arranged along the scanning direction of the laser light LB has a direction X crossing the scanning direction of the laser light LB (in FIG. 2A and FIG. (Axial direction). That is, the plurality of micro lenses 152 are arranged in a matrix or a lattice.

  The outer shape of each lens surface of the plurality of micro lenses 152 is a regular hexagon in plan view (that is, on the XY plane). However, the outer shape of at least one lens surface of the plurality of microlenses 152 has an arbitrary shape other than a regular hexagon in plan view (for example, a circle, a square, an arbitrary rectangle, or any other shape). There may be.

  The characteristics (for example, the outer shape and curvature of the lens surface) of the plurality of micro lenses 152 are the same. However, at least some of the characteristics of the plurality of microlenses 152 may be different from at least some of the other characteristics of the plurality of microlenses 152.

  The shape of one lens surface of each micro lens 152 is a convex lens shape. The other lens surface of each micro lens 152 has a planar shape.

  The plurality of microlenses 152 are arranged such that the lens surface of each microlens 152 intersects the optical path of the laser light LB. Therefore, the lens surfaces of the plurality of microlens arrays 152 (particularly, the lens surfaces irradiated with the laser light LB) constitute a scanning surface 153 on which the laser light LB scans. Therefore, the scanning surface 153 is a surface that intersects the optical path of the laser light LB.

  The laser beam LB applied to the scanning surface 153 forms a laser spot LS on the scanning surface 153. The laser spot LS moves with the scanning of the laser beam LB. For example, the laser light LB scans the scanning surface 153 so as to be sequentially diffused by the plurality of micro lenses 152. In this case, the laser spot LS moves so as to be sequentially positioned on the lens surfaces of the plurality of microlenses 152 with the scanning of the laser beam LB.

  The spot diameter of the laser spot LS is smaller than the arrangement interval between two adjacent micro lenses 152. Therefore, the laser light source unit 11 may emit an appropriate laser beam LB such that the spot diameter of the laser spot LS is smaller than the interval between two adjacent microlenses 152. Alternatively, the image display device 1 adjusts the beam diameter of the laser light LB emitted from the laser light source unit 11 so that the spot diameter of the laser spot LS is smaller than the arrangement interval between two adjacent microlenses 152. (For example, a beam expander).

  Referring again to FIG. 1, the scanning position detection plate 16 is a member arranged to be adjacent to the screen 15 along the optical path of the laser light LB. The scanning position detection plate 16 is a member that detects a scanning position of the laser beam LB on the screen 15. That is, the scanning position detection plate 16 is a member that detects the formation position of the laser spot LS on the scanning surface 153 of the screen 15.

  Here, the configuration of the scanning position detection plate 16 will be described with reference to FIGS. 3 (a) to 3 (e). FIG. 3A is a plan view showing the scanning position detection plate 16 observed from a direction along the optical path of the laser light LB. FIG. 3B is a cross-sectional view of the microlens 152 and the light receiving element 162 showing a positional relationship between the micro lens 152 provided in the screen 15 and the light receiving element 162 provided in the scanning position detection plate 16. FIG. 3C shows the laser beam transmitted through the microlens 152 when the center of the laser spot LS is not displaced from the center of the lens surface of the microlens 152 along the direction intersecting the scanning direction of the laser beam LB. FIG. 9 is a cross-sectional view of the microlens 152 and the light receiving element 162, showing how light is received by the light receiving element 162 of LB. FIG. 3D shows a laser transmitted through the microlens 152 when the center of the laser spot LS is shifted from the center of the lens surface of each microlens 152 along a direction intersecting the scanning direction of the laser light LB. FIG. 9 is a cross-sectional view of the microlens 152 and the light receiving element 162, showing how light LB is received by the light receiving element 162. FIG. 3E is a graph showing a relationship between a difference signal output from the pair of light receiving elements 162 and a shift amount (shift amount) of the center of the laser spot LS with respect to the center of the lens surface of the micro lens 152. In FIG. 3, similarly to the description of the screen 15, the scanning position detection plate 16 will be described using an XYZ coordinate system including an X-axis, a Y-axis, and a Z-axis, which are orthogonal to each other, for convenience of description.

  As shown in FIG. 3A, the scanning position detection plate 16 is a plate-shaped member. However, the scanning position detection plate 16 may be a member having a shape (for example, a disk shape) different from the plate shape.

  The scanning position detection plate 16 is arranged such that a detection surface 161 which is a surface facing the screen 15 among the surfaces of the scanning position detection plate 16 is parallel to the scanning surface 153 of the screen 15. In at least a part of the detection surface 161 of the scanning position detection plate 16, a plurality of light receiving elements 162 arranged along a direction (X-axis direction) intersecting the scanning direction of the laser light LB are arranged. I have. In the example shown in FIG. 2, both ends of the microlens array 151 (scanning surface 153) along the scanning direction (Y-axis direction) of the laser light LB overlap with each of the two ends along the optical path (Z-axis direction) of the laser light LB. A plurality of light receiving elements 162 arranged in a direction (X-axis direction) intersecting with the scanning direction of the laser light LB are arranged in a partial area of the detection surface 161.

  The plurality of light receiving elements 162 are arranged so as to have a predetermined positional relationship with the plurality of micro lenses 152. Specifically, as shown in FIG. 3B, a pair of light receiving elements 162 adjacent in a direction (X-axis direction) intersecting the scanning direction of the laser light LB corresponds to one microlens array 152. , A plurality of light receiving elements 162 are arranged. In other words, as shown in FIG. 3B, a pair of light receiving elements 162 and one microlens array 152 adjacent to each other along a direction (X-axis direction) intersecting the scanning direction of the laser light LB are formed by the laser light LB. A plurality of light receiving elements 162 are arranged adjacent to each other along the optical path (Z-axis direction). In particular, the plurality of light receiving elements 162 are arranged along the optical path of the laser light LB such that the center of the lens surface of each micro lens 152 and the boundary between the pair of light receiving elements 162 are aligned.

  Since the plurality of light receiving elements 162 are arranged so as to have a predetermined positional relationship with the plurality of micro lenses 152, the laser light LB of the laser light LB is determined based on the light receiving results of the pair of light receiving elements 162 corresponding to each micro lens 152. The formation position of the laser spot LS with respect to each micro lens 152 along the direction intersecting the scanning direction is detected. Specifically, as shown in FIG. 3C, when the center of the laser spot LS is not displaced from the center of the lens surface of each micro lens 152 along a direction intersecting the scanning direction of the laser beam LB. Is, the laser light LB is evenly applied to the pair of light receiving elements 162 corresponding to each micro lens 152. Therefore, the signal level of the difference signal (so-called push-pull signal) of the light receiving result of the pair of light receiving elements 162 corresponding to each micro lens 152 becomes zero. On the other hand, as shown in FIG. 3D, when the center of the laser spot LS is displaced from the center of the lens surface of each micro lens 152 along a direction intersecting the scanning direction of the laser light LB, The laser light LB is not evenly applied to the pair of light receiving elements 162 corresponding to each micro lens 152. Therefore, the signal level of the difference signal of the light reception result of the pair of light receiving elements 162 corresponding to each micro lens 152 does not become zero.

  For this reason, as shown in FIG. 3E, the signal level of the difference signal is based on the center of the lens surface of each micro lens 152, and the laser spot LS along the direction intersecting with the scanning direction of the laser light LB. The signal level is in accordance with the center shift amount (shift amount). That is, the signal level of the difference signal is a signal level corresponding to the formation position of the laser spot LS with respect to each microlens 152 along the direction intersecting the scanning direction of the laser light LB. Therefore, based on the signal level of the difference signal of the light reception result of the pair of light receiving elements 162 corresponding to each micro lens 152, the position where the laser spot LS is formed for each micro lens 152 along the direction intersecting the scanning direction of the laser light LB. Is detected. Conversely, if control is performed to match the signal level of the difference signal to the desired signal level, the position at which the laser spot LS is formed is adjusted along the direction crossing the scanning direction of the laser beam LB.

  3A to 3E, a pair of light receiving elements 162 adjacent to each other along a direction (X-axis direction) intersecting with the scanning direction of the laser beam LB corresponds to one microlens array 152. , A plurality of light receiving elements 162 are arranged. In this case, as described above, based on the signal level of the difference signal, the shift amount of the center of the laser spot LS along the direction intersecting with the scanning direction of the laser beam LB with respect to the center of the lens surface of each microlens 152 Is detected. On the other hand, the plurality of light receiving elements 162 are arranged such that four light receiving elements 162 adjacent in a grid along the scanning direction of the laser beam LB and a direction intersecting the scanning direction correspond to one microlens array 152. May be. In this case, the shift amount of the center of the laser spot LS along an arbitrary direction based on the center of the lens surface of each micro lens 152 is detected based on the signal level of the difference signal.

  In FIG. 1 again, the combiner 17 reflects the laser light LB (that is, diffused light) transmitted through the screen 15 toward the observer. As a result, the observer can observe an image displayed by the laser light LB transmitted through the screen 15 (in other words, an image formed on the screen 15 by the laser light LB) as a virtual image.

  The controller 18 is a central processing unit that controls the image display device 1. In this embodiment, in particular, the controller 18 includes a laser control unit 181 and a MEMS control unit 183, which is a specific example of “adjustment unit”, as logical processing blocks implemented therein.

  The laser controller 181 controls the laser light source unit 11. Specifically, the laser control unit 181 determines an emission pattern of the laser light LB by the laser light source unit 11 based on the image signal. Thereafter, the laser control unit 181 controls the laser light source unit 11 to emit the laser beam LB in the determined emission pattern while synchronizing with the swing timing of the MEMS scanner 14 swinging under the control of the MEMS control unit 183. I do.

  The MEMS control unit 183 controls the MEMS scanner 14. Specifically, the MEMS control unit 183 controls the MEMS scanner 14 so that the MEMS scanner 14 moves in synchronization with the emission pattern of the laser light LB by the laser light source unit 11. That is, the MEMS control unit 183 controls the MEMS scanner 14 so that the laser light LB reflected by the MEMS scanner 14 appropriately scans the scanning surface 153 of the screen 15.

  In addition, the MEMS control unit 183 controls the MEMS scanner 14 based on the detection result of the scanning position detection unit 16 so as to adjust the formation position of the laser spot LS on the scanning surface 153. More specifically, based on the detection result of the scanning position detection unit 16, the MEMS control unit 183 forms a laser spot LS forming position (for example, the scanning of the laser light LB) along a direction intersecting the scanning direction of the laser light LB. The MEMS scanner 14 is controlled so as to adjust the position of the laser spot LS with respect to each microlens 152 along the direction crossing the direction. In this case, the MEMS control unit 183 adjusts the formation position of the laser spot LS by, for example, adjusting the swing mode (eg, swing timing, swing angle, swing amount, and the like) of the MEMS scanner 14. The MEMS scanner 14 is controlled as described above. The adjustment operation of the formation position of the laser spot LS performed under the control of the MEMS control unit 182 will be described later in detail (see FIGS. 5A to 5E).

(2) Relationship between luminance of image and viewpoint position at which image can be observed Subsequently, with reference to FIG. 4, luminance of an image displayed by laser light LB diffused by screen 15 and the image can be observed. The relationship with the various viewpoint positions will be described. FIG. 4A is an explanatory diagram illustrating a state of diffusion of the laser light LB by the screen 15 when the diffusion angle of the laser light LB in each micro lens 152 is relatively small. FIG. 4B is an explanatory diagram showing a state of diffusion of the laser light LB by the screen 15 when the diffusion angle of the laser light LB in each micro lens 152 is relatively large.

  As shown in FIG. 4A, when the diffusion angle of the laser light LB in each micro lens 152 is relatively small, each micro lens 152 diffuses the laser light LB toward a relatively narrow range. . When the diffusion angle of the laser light LB is relatively small (that is, each micro lens 152 diffuses the laser light LB toward a relatively narrow range), the laser light LB reaching the observer located at a certain viewpoint position Becomes relatively large. When the light amount of the laser light LB reaching the observer becomes relatively large, the observer recognizes that the luminance of the image displayed by the laser light LB is relatively large (that is, relatively high).

  However, when the diffusion angle of the laser light LB in each microlens 152 is relatively small, the area where all of the laser light diffused by the plurality of microlenses 152 of the screen 15 reaches becomes relatively narrow. That is, when the diffusion angle of the laser beam LB in each micro lens 152 is relatively small, the viewpoint position at which the entire image displayed by the laser beam LB diffused by the screen 15 can be observed is within a relatively narrow range. Will be distributed. For example, in the example shown in FIG. 4A, at the viewpoint position A1, all of the laser light diffused by the plurality of microlenses 152 included in the screen 15 arrives. The entire displayed image is observable. On the other hand, at the viewpoint position A2, the laser light LB diffused by a part of the plurality of microlenses 152 of the screen 15 corresponding to the pixels D and E does not reach. In other words, at the viewpoint position A2, the laser LB does not reach while the laser light LB is scanning some of the microlenses 152 corresponding to the pixels D and E. Therefore, at the viewpoint position A2, the entire image displayed by the laser light LB diffused by the screen 15 cannot be observed. Typically, at the viewpoint position A2, a part of an image displayed by the laser light LB diffused by the screen 15 (for example, an image lacking the pixels D and E) is observed.

  As described above, when the diffusion angle of the laser light LB in each micro lens 152 becomes relatively small, the brightness of the image displayed by the laser light LB becomes relatively large, but the image displayed by the laser light LB is observed. Possible viewpoint positions are distributed in a relatively narrow range. Therefore, the observer who observes the image displayed by the image display device 1 needs to adjust the observer's viewpoint to a viewpoint position distributed in a relatively narrow range (that is, a viewpoint position at which the image can be observed). Be restricted. In other words, it may be difficult for an observer who observes the image displayed by the image display device 1 to observe the image from a desired viewpoint position.

  Therefore, in order to widen the distribution range of the viewpoint position at which the image displayed by the laser light LB can be observed, a countermeasure to increase the diffusion angle of the laser light LB in each micro lens 152 relatively is assumed. Note that the diffusion angle of the laser beam LB in each micro lens 152 increases as the spot diameter of the laser spot LS increases.

  In this case, as shown in FIG. 4B, the area where all of the laser light diffused by the plurality of microlenses 152 provided in the screen 15 reaches becomes relatively large. That is, when the diffusion angle of the laser light LB in each microlens 152 is relatively large, the viewpoint position at which the entire image displayed by the laser light LB diffused by the screen 15 can be observed is relatively large. It will be distributed over a wide range. For example, in the example shown in FIG. 4B, at the viewpoint position B1, all of the laser light diffused by the plurality of microlenses 152 included in the screen 15 reaches, and thus the laser light LB diffused by the screen 15 causes The entire displayed image is observable. As can be seen by comparing FIGS. 4A and 4B, the distribution range of the viewpoint position B1 is wider than the distribution range of the viewpoint position A1.

  However, when the diffusion angle of the laser light LB in each micro lens 152 is relatively large, each micro lens 152 diffuses the laser light LB toward a relatively wide range. When the diffusion angle of laser light LB is relatively large (that is, each micro lens 152 diffuses laser light LB toward a relatively wide range), laser light LB reaching an observer located at a certain viewpoint position Is relatively small. When the amount of the laser light LB reaching the observer is relatively small, the observer recognizes that the brightness of the image displayed by the laser light LB is relatively small (that is, relatively low).

  As described above, when the diffusion angle of the laser light LB in each microlens 152 becomes relatively large, the viewpoint position at which the image displayed by the laser light LB can be observed is distributed in a relatively wide range, but the laser light LB is distributed. , The brightness of the image displayed becomes relatively small. Therefore, the observer may observe a relatively dark image.

  In other words, it is difficult for the image display device 1 to display an image that is relatively large in luminance and can be observed from a desired viewpoint position only by adjusting the diffusion angle of the laser beam LB in each microlens 152. It is presumed that there is.

  Therefore, the image display apparatus 1 of the present embodiment first maintains a state in which the diffusion angle of the laser beam LB in each micro lens 152 is relatively small (for example, the spot diameter of the laser spot LS is set to two adjacent micro lenses). By making the pitch smaller than the arrangement pitch of 152 (or smaller than the diameter of the lens surface of each micro lens 152), the brightness of the displayed image is increased. Then, the image display device 1 displays an image that can be observed from a desired viewpoint position by adjusting the diffusion direction of the laser light LB in each micro lens 152. As a result, the image display device 1 can display an image whose luminance is relatively large and which can be observed from a desired viewpoint position.

  In order to adjust the diffusion direction of the laser light LB in each microlens 152, the image display device 1 forms a laser spot LS along a direction intersecting the scanning direction of the laser light LB (for example, the scanning direction of the laser light LB). (The position at which the laser spot LS is formed with respect to each microlens 152 along the direction intersecting with).

  Hereinafter, the adjustment operation of the formation position of the laser spot LS performed for adjusting the diffusion direction of the laser beam LB in each micro lens 152 will be further described.

(3) Adjusting operation of laser spot LS forming position by MEMS control unit 183 Next, referring to FIGS. 5A to 5B and FIGS. 6 and 7, the laser spot LS by the MEMS control unit 183 will be described. The adjustment operation of the formation position of will be described. FIGS. 5A to 5E respectively show a shift amount of the formation position of the beam spot LS along a direction intersecting the scanning direction of the laser beam LB with respect to the center of the lens surface of the microlens 152, and each microlens 152. FIG. 4 is an explanatory diagram showing a relationship between a laser beam LB and a diffusion direction in FIG. FIG. 6 is an explanatory diagram showing the formation position of the beam spot LS with respect to the center of the lens surface of the micro lens 152 when the image display device 1 displays an image observable from the desired viewpoint position # 6. FIG. 7 is an explanatory diagram illustrating the formation position of the beam spot LS with respect to the center of the lens surface of the micro lens 152 when the image display device 1 displays an image that can be observed from the desired viewpoint position # 7.

  As shown in FIGS. 5A to 5E, the laser light in each microlens 152 is formed according to the formation position of the laser spot LS with respect to each microlens 152 along the direction intersecting the scanning direction of the laser light LB. The LB diffusion direction changes. More specifically, when a certain microlens 152 is irradiated with the laser beam LB, the position of the laser spot LS along a direction intersecting the scanning direction of the laser beam LB with respect to the certain microlens 152 is determined. Then, the diffusion direction of the laser light LB in the certain micro lens 152 changes. Hereinafter, a description will be given of a case where the laser beam LB is irradiated to the microlens 152 # 5 as an example.

  For example, as shown on the left side of FIG. 5A, the shift amount of the formation position of the beam spot LS along the direction intersecting the scanning direction of the laser beam LB with respect to the center of the lens surface of the micro lens 152 # 5 is -d1. Assume that it is. 5 (a) to 5 (e), a shift toward the right with respect to the traveling direction of the laser beam LB (from FIG. 5 (a) to FIG. 5 (e), a direction from the left to the right). The amount (in FIGS. 5A to 5E, the amount of shift toward the lower side in the drawing) is defined as a positive shift amount. In this case, as shown in the center of FIG. 5A, the diffusion direction of the laser light LB in the micro lens 152 # 5 is the first direction D1.

  The right side of FIG. 5A illustrates the diffusion of the laser beam LB that scans along one scanning line on the scanning surface 153 under the condition that the shift amount of the formation position of the beam spot LS is −d1. 3 shows the angle distribution (ie, the diffusion distribution of the laser beam LB by the screen 15). In other words, on the right side of FIG. 5A, the laser beam LB that scans along one scanning line on the scanning surface 153 under the condition that the shift amount of the formation position of the beam spot LS is −d1 is the screen. 15 shows a projection distribution of the laser beam LB on the virtual projection plane when the laser light LB is projected on a virtual projection plane after being diffused by the laser light 15. Therefore, on the right side of FIG. 5A, an area where the laser light LB reaches (a relatively bright area) indicates a viewpoint position at which an image displayed by the laser light LB can be observed. 5B to FIG. 5E, the same laser light LB as that on the right side of FIG. 5A except that the shift amount of the formation position of the beam spot LS is different. 3 shows the distribution of the diffusion angle.

  Subsequently, as shown on the left side of FIG. 5B, the MEMS control unit 183 controls the MEMS scanner so that the shift amount of the formation position of the beam spot LS changes from −d1 to −d2 (where d1> d2). It is assumed that 14 swing modes are adjusted. In this case, as shown in the center of FIG. 5B, the diffusion direction of the laser light LB in the micro lens 152 # 5 changes to a second direction D2 different from the first direction D1. As a result, as shown on the right side of FIG. 5B, a region where the laser light diffused by the microlens 152 # 5 reaches (that is, a viewpoint position at which an image displayed by the laser light LB can be observed) ) Also changes.

  Subsequently, as shown on the left side of FIG. 5C, the MEMS control unit 183 adjusts the swing mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS changes from -d2 to 0. Assume the case. In this case, as shown in the center of FIG. 5C, the diffusion direction of the laser light LB in the micro lens 152 # 5 changes to a third direction D3 different from the first direction D1 and the second direction D2. . As a result, as shown on the right side of FIG. 5C, the region where the laser light diffused by the microlens 152 # 5 reaches (that is, the viewpoint position where the image displayed by the laser light LB can be observed) ) Also changes.

  Subsequently, as shown on the left side of FIG. 5D, when the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS changes from 0 to + d2. Is assumed. In this case, as shown in the center of FIG. 5D, the diffusion direction of the laser beam LB in the micro lens 152 # 5 changes from the first direction D1 to a fourth direction D4 different from the third direction D3. . As a result, as shown on the right side of FIG. 5D, a region where the laser light diffused by the microlens 152 # 5 reaches (that is, a viewpoint position at which an image displayed by the laser light LB can be observed) ) Also changes.

  Subsequently, as shown on the left side of FIG. 5E, the MEMS control unit 183 adjusts the oscillating mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS changes from + d2 to + d1. Is assumed. In this case, as shown in the center of FIG. 5E, the diffusion direction of the laser beam LB in the micro lens 152 # 5 changes from the first direction D1 to a fifth direction D5 different from the fourth direction D4. . As a result, as shown on the right side of FIG. 5E, a region where the laser light diffused by the microlens 152 # 5 reaches (that is, a viewpoint position at which an image displayed by the laser light LB can be observed) ) Also changes.

  As described above, it can be seen that the diffusion direction of the laser light LB in each microlens 152 changes according to the formation position of the laser spot LS with respect to each microlens 152 along the direction intersecting the scanning direction of the laser light LB. Then, conversely, if the formation position of the laser spot LS is adjusted for each microlens 152, each microlens 152 can diffuse the laser light LB in a desired diffusion direction corresponding to a desired viewpoint position. Is assumed.

  For example, as shown in FIG. 6, it is assumed that the image display device 1 displays an image observable from the viewpoint position # 6.

  In this case, the MEMS control unit 183 adjusts the swing mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the microlens 152 # A corresponding to the pixel A becomes −d61. In this case, the microlens 152 # A emits the laser beam LB in the diffusion direction # 6A corresponding to the viewpoint position # 6 (that is, the diffusion direction # 6A in which the laser beam LB can reach the viewpoint position # 6). To spread.

  Similarly, the MEMS control unit 183 adjusts the oscillating mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the microlens 152 # B corresponding to the pixel B becomes −d62. In this case, the micro lens 152 # B causes the laser beam LB to move in the diffusion direction # 6B corresponding to the viewpoint position # 6 (that is, the diffusion direction # 6B that allows the laser beam LB to reach the viewpoint position # 6). To spread.

  Similarly, the MEMS control unit 183 adjusts the swing mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the microlens 152 # C corresponding to the pixel C becomes zero. In this case, the microlens 152 # C causes the laser beam LB to move in the diffusion direction # 6C corresponding to the viewpoint position # 6 (that is, the diffusion direction # 6C in which the laser beam LB can reach the viewpoint position # 6). To spread.

  Similarly, the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 such that the shift amount of the formation position of the beam spot LS with respect to the microlens 152 # D corresponding to the pixel D becomes + d62. In this case, the microlens 152 # D transmits the laser light LB toward the diffusion direction # 6D corresponding to the viewpoint position # 6 (that is, the diffusion direction # 6D that allows the laser light LB to reach the viewpoint position # 6). To spread.

  Similarly, the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the micro lens 152 # E corresponding to the pixel E becomes + d61. In this case, the microlens 152 # E emits the laser beam LB in the diffusion direction # 6E corresponding to the viewpoint position # 6 (that is, the diffusion direction # 6E in which the laser beam LB can reach the viewpoint position # 6). To spread.

  The MEMS control unit 183 performs beam spots on the other microlenses 152 such that the other microlenses 152 diffuse the laser beam LB in the diffusion direction corresponding to the viewpoint position # 6. The swinging mode of the MEMS scanner 14 is adjusted so that the shift amount of the LS formation position becomes a predetermined amount.

  As a result, all of the laser beams diffused by the plurality of microlenses 152 of the screen 15 reach the viewpoint position # 6. Therefore, the observer located at the viewpoint position # 6 can observe the entire image displayed by the laser light LB diffused by the screen 15. That is, the image display device 1 can display an image observable from the viewpoint position # 6.

  On the other hand, for example, as shown in FIG. 7, the image display device 1 newly replaces the image observable from the viewpoint position # 6 with an image observable from the viewpoint position # 7 different from the viewpoint position # 6. Assume that it is displayed.

  In this case, the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the microlens 152 # A corresponding to the pixel A changes from -d61 to -d71. In this case, the microlens 152 # A moves the laser toward the diffusion direction # 7A corresponding to the viewpoint position # 7 (that is, the diffusion direction # 7A that allows the laser light LB to reach the viewpoint position # 7). Diffuses light LB.

  Similarly, the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the micro lens 152 # B corresponding to the pixel B changes from -d62 to -d72. In this case, the micro lens 152 # B causes the laser beam LB to move in the diffusion direction # 7B corresponding to the viewpoint position # 7 (that is, the diffusion direction # 7B that allows the laser beam LB to reach the viewpoint position # 7). To spread.

  Similarly, the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the microlens 152 # C corresponding to the pixel C changes from 0 to -d73. In this case, the micro lens 152 # C causes the laser beam LB to move in the diffusion direction # 7C corresponding to the viewpoint position # 7 (that is, the diffusion direction # 7C in which the laser beam LB can reach the viewpoint position # 7). To spread.

  Similarly, the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the microlens 152 # D corresponding to the pixel D changes from + d62 to -d74. In this case, the microlens 152 # D outputs the laser light LB toward the diffusion direction # 7D corresponding to the viewpoint position # 7 (that is, the diffusion direction # 7D that allows the laser light LB to reach the viewpoint position # 7). To spread.

  Similarly, the MEMS control unit 183 adjusts the swinging mode of the MEMS scanner 14 so that the shift amount of the formation position of the beam spot LS with respect to the micro lens 152 # E corresponding to the pixel E changes from + d61 to -d75. In this case, the microlens 152 # E emits the laser light LB toward the diffusion direction # 7E corresponding to the viewpoint position # 7 (that is, the diffusion direction # 7E that allows the laser light LB to reach the viewpoint position # 7). To spread.

  The MEMS control unit 183 performs beam spots on the other microlenses 152 so that the other microlenses 152 diffuse the laser beam LB in the diffusion direction corresponding to the viewpoint position # 7. The swinging mode of the MEMS scanner 14 is adjusted so that the shift amount of the LS formation position becomes a predetermined amount.

  As a result, all of the laser beams diffused by the plurality of microlenses 152 of the screen 15 reach the viewpoint position # 7. Therefore, the observer located at the viewpoint position # 7 can observe the entire image displayed by the laser light LB diffused by the screen 15. Alternatively, even when the observer's viewpoint moves from the viewpoint position # 6 to the viewpoint position # 7, the observer still observes the entire image displayed by the laser light LB diffused by the screen 15. Can be.

  As described above, the image display device 1 of the present embodiment can increase the brightness of the displayed image by maintaining a state where the diffusion angle of the laser beam LB in each microlens 152 is relatively small. . Furthermore, the image display device 1 of the present embodiment can display an image that can be observed from a desired viewpoint position by adjusting the diffusion direction of the laser light LB in each microlens 152. In other words, the image display apparatus 1 of the present embodiment adjusts the diffusion direction of the laser beam LB in each microlens 152 to substantially distribute the viewpoint position at which the image can be observed in a relatively wide range. Can be done. As a result, the image display device 1 can display an image whose luminance is relatively large and which can be observed from a desired viewpoint position.

  Adjustment of the formation position of the laser spot LS leads to adjustment of the diffusion direction of the laser light LB in the microlens 152, typically when the spot diameter of the laser spot LS is smaller than the arrangement pitch of the microlenses 152. It is. That is, when the spot diameter of the laser spot LS is larger than the arrangement pitch of the microlenses 152, the adjustment of the formation position of the laser spot LS does not or does not easily lead to the adjustment of the diffusion direction of the laser light LB in the microlens 152. Therefore, in addition to or instead of the purpose of increasing the brightness of the image, the laser spot LS is also adjusted for the purpose of realizing the adjustment of the diffusion direction of the laser beam LB in the microlens 152 by adjusting the formation position of the laser spot LS. Is preferably smaller than the arrangement pitch of the micro lenses 152.

  Here, when the image display device 1 displays an image observable from a certain viewpoint position, the diffusion angle of the laser beam LB in the microlens 152 is defined as β. On the other hand, when the image display device of the comparative example that does not adjust the formation position of the laser spot LS displays an image image that can be observed from the same viewpoint position, the diffusion angle of the laser beam LB in the microlens 152 is defined as α. . In this case, it is preferable that the spot diameter of the laser spot LS and the arrangement pitch of the micro lenses 152 have a relationship of: spot diameter of the laser spot LS = array pitch of the micro lenses 152 × (β / α). In this case, both the image display device 1 and the image display device of the comparative example can display an image observable from a certain viewpoint position. On the other hand, the brightness of the image displayed by the image display device 1 is (α / β) times the brightness of the image displayed by the image display device of the comparative example. Therefore, the image display device 1 can display an image observable from a certain viewpoint position with relatively large brightness as compared with the image display device of the comparative example.

  In addition, in this embodiment, the image display device 1 can display an image observable from a desired viewpoint position by adjusting the swinging mode of the MEMS scanner 14. That is, the image display device 1 can display an image that can be observed from a desired viewpoint position without moving the combiner 17 (or other physical components) having a relatively large size. Therefore, a relatively low cost and a relatively small size of the image display device 1 are realized.

  The configuration and operation of the image display device 1 described with reference to FIGS. 1 to 7 are examples. Therefore, at least part of the configuration and operation of the image display device 1 may be appropriately modified. Hereinafter, an example of modification of at least a part of the configuration and operation of the image display device 1 will be described.

  The MEMS control unit 183 may automatically adjust the oscillating mode of the MEMS scanner 14 according to the viewpoint position of the observer. For example, the MEMS control unit 183 may automatically adjust the swing mode of the MEMS scanner 14 so as to display an image observable from the viewpoint position of the observer. In this case, it is preferable that the image display device 1 detects the viewpoint position of the observer or obtains information on the viewpoint position of the observer. Alternatively, the MEMS control unit 183 may adjust the oscillating mode of the MEMS scanner 14 in accordance with the contents of an instruction of the observer specifying the viewpoint position. For example, the MEMS control unit 183 may adjust the swing mode of the MEMS scanner 14 so as to display an image that can be observed from a viewpoint position designated by the observer.

  The above-described screen 15 is a transmission screen that transmits the laser beam LB. However, a reflective screen that reflects the laser beam LB may be used as the screen 15.

  The screen 15 may include, in addition to or in place of the microlens array 151, any optical element in which element portions or element regions capable of diffusing the laser light LB are periodically arranged. The screen 15 may be any optical element in which element portions or element regions capable of diffusing the laser light LB are periodically arranged in addition to or instead of the microlens array 151. An example of such an optical element is a diffractive optical element (DOE: Diffractive Optical Element).

  The image display device 1 may display the same or different images at a plurality of viewpoint positions in addition to or instead of displaying an image at a single viewpoint position. Hereinafter, an example in which images are displayed at a plurality of viewpoint positions will be described with reference to FIGS. 8 and 9. 8 and 9 are explanatory diagrams each showing an example of displaying an image at a plurality of viewpoint positions.

  As shown in FIG. 8, the MEMS control unit 183 determines that the microlenses 152 # A and 152 # B located relatively on one side (the upper side in FIG. 8) of the screen 15 correspond to the viewpoint position # 8-1. The shift amount of the formation position of the beam spot LS with respect to each of the micro lenses 152 # A and 152 # B may be adjusted so that the laser light LB is diffused in the diffusion direction # 8-1. On the other hand, the MEMS control unit 183 determines that the micro lenses 152 # C, 152 # D, and 152 # E located relatively on the other side (the lower side in FIG. 8) of the screen 15 correspond to the viewpoint position # 8-2. The shift amount of the formation position of the beam spot LS with respect to each of the micro lenses 152 # C, 152 # D and 152 # E may be adjusted so as to diffuse the laser light LB in the diffusion direction # 8-2. . The MEMS control unit 183 also causes all the other microlenses 152 to diffuse the laser light LB in the diffusion direction corresponding to one of the viewpoint positions # 8-1 and # 8-2. Alternatively, the shift amount of the formation position of the beam spot LS with respect to the other micro lenses 152 may be adjusted. As a result, the image display device # 1 displays the first image observable from the viewpoint position # 8-1 and the second image observable from the viewpoint position # 8-2 (however, the second image is the first image (Which may be the same as or different from the image of the above) can be displayed substantially simultaneously. For example, when the image display device # 1 is mounted on a vehicle, the image display device # 1 controls both the viewpoint position # 8-1 corresponding to the driver's seat and the viewpoint position # 8-2 corresponding to the passenger seat. Can be displayed substantially simultaneously. Alternatively, for example, when the image display device # 1 is mounted on a vehicle, the image display device # 1 can display an image corresponding to a speedometer that can be observed from a viewpoint position # 8-1 that is relatively looked down from above. It is possible to display navigation images observable from viewpoint position # 8-2, which is relatively relatively viewed from below, at substantially the same time.

  As illustrated in FIG. 9, the MEMS control unit 183 determines that two adjacent microlenses 152 along a direction intersecting the scanning direction of the laser beam LB (in FIG. 9, the vertical direction) correspond to different diffusion directions corresponding to different viewpoint positions. The amount of shift of the formation position of the beam spot LS with respect to the micro lens 152 may be adjusted so that the laser beam LB is diffused toward. For example, the MEMS control unit 183 controls the micro lenses 152 # B and 152 # D such that the micro lenses 152 # B and 152 # D diffuse the laser light LB in the diffusion direction # 8-1 corresponding to the viewpoint position # 8-1. And the shift amount of the formation position of the beam spot LS with respect to each of the beam spots 152 and 152 # D. On the other hand, for example, the MEMS control unit 183 causes the micro lenses 152 # A, 152 # C, and 152 # E to diffuse the laser light LB in the diffusion direction # 8-2 corresponding to the viewpoint position # 8-2. Alternatively, the shift amount of the formation position of the beam spot LS with respect to each of the micro lenses 152 # A, 152 # C, and 152 # E may be adjusted.

  In addition, the present invention can be appropriately changed within a scope that does not contradict the gist or idea of the invention that can be read from the claims and the entire specification, and an image display device with such a change is also a technical idea of the present invention. include.

DESCRIPTION OF SYMBOLS 1 Image display apparatus 11 Laser light source unit 13 Condensing lens 14 MEMS scanner 15 Screen 151 Microlens array 152 Microlens 153 Scanning surface 16 Scanning position detection plate 161 Detection surface 162 Light receiving element 17 Combiner 18 Controller 181 Laser control unit 183 MEMS control unit LB laser light LS laser spot

Claims (5)

Emitting means for emitting laser light;
Diffusion means including a plurality of optical elements that are regularly arranged along a scanning surface scanned by the laser light emitted by the emission means and each diffuse the laser light,
Forming position of a light spot formed by the laser light on the scanning surface with respect to each of the plurality of optical elements so that the laser light is diffused in a desired diffusion direction by each of the plurality of optical elements. and an adjustment means for adjusting the,
An image displayed by the laser light by changing a formation position of the light spot based on a shift amount that is a shift amount of the light spot with respect to a center of the optical element according to the desired diffusion direction; An image display device for adjusting a viewpoint position at which an image can be observed . The plurality of optical elements includes one or more first optical elements, and one or more second optical elements different from the one or more first optical elements,
The adjusting means enables a first image portion displayed by the laser light diffused by the one or more first optical elements to be observed at a first viewpoint position, and the one or more second Changing a formation position of the light spot so that a second image portion displayed by the laser light diffused by an optical element can be observed at a second viewpoint position different from the first viewpoint position;
The image display device according to claim 1, wherein: The plurality of optical elements are arranged along a scanning direction of the laser beam, and the plurality of first optical elements are arranged along the scanning direction and a plurality of second optical elements arranged differently from the plurality of first optical elements. And an element,
The adjusting unit changes the position of the light spot with respect to each of the plurality of first optical elements according to a first shift amount, and adjusts the plurality of second optical elements according to a second shift amount. Changing the formation position of the light spot with respect to each of
The image display device according to claim 1, wherein: A detecting means for detecting a viewpoint position of the observer,
The adjusting means changes the formation position of the light spot so that a viewpoint position at which an image displayed by the laser light becomes observable is a viewpoint position detected by the detection means.
The image display device according to claim 1. A viewpoint position designating means for designating a viewpoint position;
The adjusting unit changes the formation position of the light spot so that a viewpoint position at which an image displayed by the laser light can be observed is a viewpoint position designated by the line-of-sight position designation unit.
The image display device according to claim 1.

Images