VIRTUAL IMAGE DISPLAY AND METHOD FOR ADJUSTING VIRTUAL IMAGE DISPLAY

Abstract

To provide a virtual image display device that can correct the deviation between left and right video positions even if the deviation newly occurs after optical systems are assembled.SOLUTION: A virtual image display device 100 comprises: a first display device 100A for the right eye; a second display device 100B for the left eye; lens barrels BRa, BRb as assembling members AS that assemble the first display device 100A and the second display device 100B; and first and second correction units COa, COb as post-assembly adjusting devices AA that adjust a display state for the first display device 100A and the second display device 100B assembled by the assembling members AS.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a virtual image display device, such as a head-mounted display, that enables the formation and observation of a virtual image. [Background technology]

[0002] In a binocular virtual image display device that enables the formation and observation of virtual images, like a head-mounted display, the optical axes of the left and right optical systems are adjusted to align the left and right image positions. For example, a known device uses an elastic sealing member to prevent foreign matter from entering during tasks such as adjusting the position of the optical system (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-160115 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, even if the optical system is assembled with high precision using a technique such as that of Patent Document 1, there is a possibility that a new deviation in the optical axis of the optical system may occur during the process of mounting the board and assembling the exterior after the assembly of the optical system. In particular, even a slight deviation in the image position between the left and right may impose a great burden on the user (wearer). [Means for solving the problem]

[0005] A virtual image display device according to one aspect of the present invention includes a first display device for the right eye, a second display device for the left eye, an assembly member for assembling the first display device and the second display device, and a post-assembly adjustment device for adjusting the display state of the first display device and the second display device assembled by the assembly member. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is an external perspective view for explaining an overview of a virtual image display device according to a first embodiment. [Diagram 2] FIG. 1 is a diagram showing an example of an optical system that constitutes a virtual image display device. [Diagram 3] FIG. 2 is a partially enlarged view for explaining each part and an optical path of an optical system. [Figure 4] FIG. 11 is a perspective view for explaining an example of alignment during assembly of the optical system. [Diagram 5] FIG. 11 is a plan view conceptually showing alignment when assembling an optical system. [Figure 6] 11A and 11B are conceptual diagrams illustrating positional deviation in a display state. [Figure 7] FIG. 13 is a plan view conceptually showing an example of a state after the optical system is assembled. [Figure 8] 8 is a plan view conceptually showing adjustment of the display state after the optical system shown in FIG. 7 is assembled. [Figure 9] FIG. 11 is a block diagram for explaining an example of image processing for adjusting a display state. [Figure 10] FIG. 2 is a conceptual diagram showing an example of a display surface of a display element. [Figure 11] FIG. 13 is an external perspective view illustrating a modified example of the virtual image display device. [Figure 12] FIG. 11 is a block diagram illustrating an example of image processing for adjusting a display state in a virtual image display device according to a second embodiment. [Figure 13] FIG. 11 is an external perspective view for explaining an overview of a virtual image display device according to a third embodiment. [Figure 14] FIG. 2 is a side cross-sectional view illustrating an example of an internal structure of the virtual image display device. [Figure 15] 11A and 11B are conceptual diagrams for explaining correction of generated distortion and rotation. [Figure 16] FIG. 13 is an external perspective view illustrating a modified example of the virtual image display device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] [First embodiment] Hereinafter, a virtual image display device according to a first embodiment of the present invention and an optical unit incorporated therein will be described with reference to Fig. 1 etc. Fig. 1 is an external perspective view for explaining an overview of a virtual image display device 100 of this embodiment, Fig. 2 is a diagram showing an example of an optical system constituting the virtual image display device 100, and Fig. 3 is a partially enlarged view for explaining each part and an optical path of the optical system constituting the virtual image display device 100. Fig. 4 is a perspective view showing an enlarged view of a part of the optical system for explaining an example of a state of alignment when assembling the optical system.

[0008] As shown in Fig. 1 etc., the virtual image display device 100 of this embodiment is a head mounted display (HMD) having an appearance like glasses, and allows an observer or wearer US wearing this virtual image display device 100 to recognize an image as a virtual image. In addition, the virtual image display device 100 allows the observer or wearer US to visually recognize or observe an external world image in a see-through manner. The virtual image display device 100 includes a first display device 100A and a second display device 100B.

[0009] 1 and the like, X, Y, and Z are an orthogonal coordinate system, the +X direction corresponds to the horizontal direction in which the eyes EY of the observer or wearer US wearing the virtual image display device 100 are aligned, the +Y direction corresponds to the upward direction perpendicular to the horizontal direction in which the eyes EY are aligned for the wearer US, and the +Z direction corresponds to the forward or front direction for the wearer US. The ±Y directions are parallel to the vertical axis or vertical direction.

[0010] As shown in Fig. 1 and Fig. 2, the first display device 100A and the second display device 100B are parts that form a virtual image for the right eye and a virtual image for the left eye, respectively. The first display device 100A for the right eye includes a first virtual image forming optical unit 101a that covers the area in front of the observer's eye in a see-through manner, and a first image forming main body unit 105a that forms image light ML. The second display device 100B for the left eye includes a second virtual image forming optical unit 101b that covers the area in front of the observer's eye in a see-through manner, and a second image forming main body unit 105b that forms image light ML.

[0011] The first and second image forming main bodies 105a and 105b are each composed of a display element (image element) 80 which is an image forming device, an optical system for forming an image such as a projection lens 30, and further, as shown in Fig. 4, a case member CS and a lens barrel BR which house these optical systems. These are further supported and housed by being covered by a cover-like exterior member 105d.

[0012] As illustrated in FIG. 2, the display element 80 is a panel-type image element (image light generating device), and is, for example, a self-luminous display device such as an organic EL (organic electroluminescence), and forms a color still image or a moving image on a two-dimensional display surface SSa. The display element 80 is driven by a display control circuit (not shown) to perform a display operation. Furthermore, the display element 80 is not limited to an organic EL, and can be replaced with an inorganic EL, an LED array, an organic LED, a laser array, a quantum dot light-emitting element, or the like. The display element 80 is not limited to a self-luminous image light generating device, and may be composed of an LCD or other light modulation element, and may form an image by illuminating the light modulation element with a light source such as a backlight. As the display element 80, instead of an LCD, LCOS (Liquid crystal on silicon, LCoS is a registered trademark), a digital micromirror device, or the like can be used.

[0013] The projection lens 30 is a projection optical system including a plurality of optical elements (four lenses in the example shown in FIG. 2) arranged along the direction in which the optical axis (entrance side optical axis) AX extends (optical axis direction), as shown in FIG. 2, for example. Also, as shown in comparison with the upper column α1 and the lower column α2 in FIG. 3, the plurality of lenses constituting the projection lens 30 are housed and supported by a lens barrel BR integrally molded by, for example, resin molding. The optical elements constituting the projection lens 30, i.e., the four lenses, can be configured to include aspherical lenses including both non-axisymmetric aspherical surfaces and axisymmetric aspherical surfaces. In this case, the intermediate image can be formed inside the light guiding member in cooperation with the optical surface or reflecting surface of the light guiding member (light guiding member 10, 10a, 10b) of the first and second virtual image forming optical units 101a and 101b described later.

[0014] In the following description, for example, when distinguishing between the right eye and the left eye, the display element 80 for the right eye may be described as display element 80a, and the display element 80 for the left eye may be described as display element 80b. Similarly, the projection lens 30 may be described as projection lenses 30a and 30b, the case members CS as case members CSa and CSb, and the lens barrel BR as lens barrel BRa and BRb.

[0015] The first and second virtual image forming optical units 101a and 101b guide the image light ML, which is the image light formed by the first and second image forming main body units 105a and 105b, and allow the external light HL and the image light ML to be viewed in an overlapping manner. In the example shown in FIG. 1, the first and second virtual image forming optical units 101a and 101b are not separate bodies but are connected at the center to form a see-through light guiding unit 100C, which is an integrated member. The see-through light guiding unit 100C is a composite light guiding device that provides an image for both eyes to the observer by guiding light. In addition, from a different perspective, the see-through light guiding unit 100C includes a pair of light guiding members 10a and 10b and a central member 50 that is a light-transmitting member, and the first virtual image forming optical unit 101a is formed by the light guiding member 10a and the light-transmitting portion 50A that is the right half of the central member 50. Similarly, the second virtual image forming optical unit 101b is formed by the light guide member 10b and a light transmitting unit 50B that is the left half of the central member 50. The light guide members 10a and 10b may be collectively referred to as the light guide member 10.

[0016] In the above, the projection lens 30 (30a, 30b) and the light guide member 10 (10a, 10b) can be collectively regarded as a light guide system 90 (90a, 90b) that guides the image light ML emitted from the display element 80 (80a, 80b).

[0017] Hereinafter, an example of the light guide of the image light ML by the virtual image display device 100 will be conceptually described with reference to FIG. 3 and the like. As described above, the virtual image display device 100 is composed of the first display device 100A and the second display device 100B. However, as shown in FIG. 2 and the like, the first display device 100A and the second display device 100B have the same structure with optical symmetry (mirror symmetry). Therefore, in FIG. 3, only the first display device 100A is shown and only the configuration on the right eye side is described, and the description of the second display device 100B is omitted. In FIG. 3 and the like, x, y, and z are an orthogonal coordinate system, the z direction corresponds to the optical axis direction of the optical system constituting the first display device 100A, the x direction and the y direction correspond to the in-plane direction in the panel surface of the display element 80b (80) with the z direction as the normal direction, the x direction corresponds to the horizontal direction, and the y direction corresponds to the vertical direction.

[0018] As illustrated in FIG. 3, the light guide member 10a of the first virtual image forming optical unit 101a has first to fifth surfaces S11 to S15 as side surfaces having optical functions. Among these, the first surface S11 and the fourth surface S14 are adjacent to each other, and the third surface S13 and the fifth surface S15 are adjacent to each other. In addition, the second surface S12 is disposed between the first surface S11 and the third surface S13. A half mirror layer is provided on the surface of the second surface S12. This half mirror layer is a reflective film (semi-transmissive reflective film) having optical transparency, and is formed by depositing a metal reflective film or a dielectric multilayer film, and has an appropriate reflectance for image light. In other words, the light guide member 10a has a transmissive reflective surface that covers the viewer's eyes when worn.

[0019] Of the first virtual image forming optical unit 101a, the light transmitting unit 50A is a member (auxiliary optical block) that assists the see-through function of the light guiding member 10a, and is fixed integrally with the light guiding member 10a to form one first virtual image forming optical unit 101a. The light transmitting unit 50A has a first transmitting surface S51, a second transmitting surface S52, and a third transmitting surface S53 as side surfaces having an optical function. The second transmitting surface S52 is disposed between the first transmitting surface S51 and the third transmitting surface S53. The first transmitting surface S51 is on a surface extending from the first surface S11 of the light guiding member 10a, the second transmitting surface S52 is a curved surface joined and integrated with the second surface S12, and the third transmitting surface S53 is on a surface extending from the third surface S13 of the light guiding member 10. In other words, the first surface S11 and the first transmitting surface S51 are adjacent to each other, and similarly, the third surface S13 and the third transmitting surface S53 are adjacent to each other, all of which are aligned flush with each other to form a smooth surface.

[0020] Hereinafter, the optical path of the image light ML will be briefly described with reference to FIG. 3 and the like. When the image light ML is emitted from the display element 80a, the light guide member 10a causes the image light ML to be incident from the projection lens 30. That is, the light guide member 10a receives the image light ML and guides it toward the eye EY of the observer or wearer US by reflection at the first to fifth surfaces S11 to S15 and the like. Specifically, the image light ML from the projection lens 30 first enters the fourth surface S14 and is reflected at the fifth surface S15, enters the fourth surface S14 again from the inside and is totally reflected, enters the third surface S13 and is totally reflected, and enters the first surface S11 and is totally reflected. The image light ML totally reflected at the first surface S11 enters the second surface S12, partially transmits through the half mirror layer provided on the second surface S12, is partially reflected, and enters the first surface S11 again and passes through. The image light ML that has passed through the first surface S11 is incident as a substantially parallel light beam on the eye EY of the wearer US or the position where the exit pupil EP, which is an equivalent position thereof, is formed. In other words, the wearer US observes an image using the image light ML as a virtual image.

[0021] As described above, the first virtual image forming optical unit 101a allows the wearer US to view the image light through the light guide member 10a, and allows the wearer US to observe an external image with little distortion through cooperation between the light guide member 10a and the light transmitting unit 50A. At this time, since the third surface S13 and the first surface S11 are substantially parallel planes (visual aberration is approximately 0), the external light HL hardly generates aberrations. Similarly, the third transmitting surface S53 and the first transmitting surface S51 are substantially parallel planes. Furthermore, since the third transmitting surface S53 and the first surface S11 are substantially parallel planes, the external light HL hardly generates aberrations. As a result, the wearer US observes an external image without distortion through the central member 50 as a light transmitting member.

[0022] 2 and the like has a similar configuration to the above-described first display device 100A. As a result, the wearer US can observe a virtual image through binocular vision while observing the outside world.

[0023] When making the above-mentioned configuration, alignment is performed so that the virtual image display positions on the left and right coincide with each other. Specifically, the positions of the display element 80 and the projection lens 30 are adjusted as shown in FIG. 4 as an example.

[0024] In the illustrated example, a recessed portion DG is provided on the side of the lens barrel BR (BRa, BRb), and a protrusion portion PR is provided on the side of the case member CS corresponding to the recessed portion DG. A slight gap is provided between the recessed portion DG and the protrusion portion PR to allow position adjustment. When joining the lens barrel BR and the case member CS, they are fitted together, and an adhesive that should be an ultraviolet-curable resin is applied to the recessed portion DG and the protrusion portion PR (not shown). As a result, the lens barrel BR and the case member CS are fixed at a desired position while allowing the relative positional relationship between them to be adjusted. When joining the lens barrel BR and the case member CS, a sealing member may be wrapped around the space between the lens barrel BR and the case member CS to seal the space between the lens barrel BR and the case member CS without any gaps.

[0025] Here, in the manufacturing process (production process) of constructing the optical system that forms the above-mentioned image, the alignment of each optical system is very important. In particular, in the case of a configuration in which the first display device 100A and the second display device 100B are provided and images are viewed by the left and right eyes, as in the virtual image display device 100 of the above-mentioned configuration, not only alignment for one eye but also alignment taking into consideration the balance between the right eye side and the left eye side is important. More specifically, in a state in which the lens barrels BRa, BRb that house the left and right projection lenses 30a, 30b, respectively, are assembled to the see-through light guide unit 100C, it is necessary to perform highly accurate positioning when attaching the case members CSa, CSb that house the display elements 80a, 80b to the lens barrels BRa, BRb (panel adjustment process). Furthermore, it is necessary to perform highly accurate angle adjustment (optical axis adjustment) of each part. For example, in order to maintain a balance between the left and right viewing states, it is necessary to make the angle error within about ±0.2°.

[0026] In order to perform high-precision relative positioning between the left and right sides so as to satisfy the above conditions, one possible mode is to use an adjustment device FA consisting of a pair of image pickup elements (cameras) FCa, FCb and an image processing device FI to perform alignment (position adjustment) when assembling the optical system, as shown in the upper column β1 of the plan view conceptually shown in Figure 5.

[0027] To explain the above alignment (position adjustment) in more detail, first, the image pickup elements FCa and FCb are installed at the formation position of the exit pupil EP assumed as the positions of the left and right eyes EY of the wearer US (see FIG. 2, etc.), while a temporary image is displayed from the optical system temporarily assembled in a position adjustable state. The image pickup elements FCa and FCb capture the temporary image, and the imaging result is sent to the image processing device FI. The image processing device FI calculates the deviation of each part of the optical system from the above imaging result (corresponding to the visual state of the wearer US) of the image pickup elements FCa and FCb assumed as the left and right eyes, and changes the relative positional relationship of each optical system temporarily assembled in an adjustably manner according to the calculation result. Although not shown, jigs are attached to the lens barrels BRa, BRb that house the projection lenses 30a, 30b and the display elements 80a, 80b (or the case members CSa, CSb that house the display elements 80a, 80b shown in Figure 4), making it possible to make the necessary physical position changes depending on the calculation results as described above.

[0028] In the above manner, the optical system is assembled in a state that satisfies the desired accuracy. In the above case, for example, the lens barrels BRa, BRb and the case members CSa, CSb shown in FIG. 4 function as members for assembling the optical systems in a state in which the positions have been adjusted, that is, as an assembly member AS for assembling the first display device 100A and the second display device 100B in a desired positional relationship. In other words, the lens barrels BRa, BRb, etc. as the assembly members AS adjust the relative posture of the left and right in the optical system constituting the virtual image display device 100. In the following, the unit in which the optical systems constituting the first and second display devices 100A, 100B are assembled by the lens barrels BRa, BRb, etc. is referred to as the optical unit OU. The optical unit OU assembled in the above manner is further assembled with various members such as the cover-like exterior member 105d, various control circuit boards, cameras, wiring members, temples, etc. (not shown), and various decorations, etc., as illustrated in the lower column β2, so that the virtual image display device 100 becomes a product that can be provided to end users (consumers).

[0029] Here, as described with reference to β1 in the upper column of FIG. 5, the optical unit OU immediately after the optical system is assembled with high precision allows viewing without any misalignment between the left and right image positions. In other words, referring to the conceptual diagram illustrated in FIG. 6, the images IM1 and IM2 of the images (virtual images) viewed by the right eye EYa and the left eye EYb of the wearer US, conceptually illustrated in the first column γ1, are naturally recognized by the wearer US as images IMA in a matched state without any misalignment, as conceptually illustrated in the second column γ2. This means that, for the optical path of the image light ML illustrated in FIG. 2, the image light ML emitted as the same image position on the left and right is incident at the same angle on the eye EY (the position where the exit pupil EP is formed).

[0030] In contrast, as described with reference to the lower column β2 of FIG. 5, after the optical unit OU is assembled with high accuracy, some distortion occurs in the optical unit OU during the process of assembling other members, and the angle of incidence of the image light ML differs between the left and right. As a result, as conceptually shown in the third column γ3 and the fourth column γ4 of FIG. 6, the images IM1 and IM2 may be misaligned. In the example shown in the third column γ3, the image is misaligned in the horizontal direction in which the observer's eyes EY are aligned, that is, in the X direction (or x direction). On the other hand, in the example shown in the fourth column γ4, the image is misaligned in the direction perpendicular to the horizontal direction in which the observer's eyes EY are aligned, that is, in the Y direction (or y direction). It is considered that, within a certain range, the wearer US, that is, humans, will process these misalignments in the brain to regard them as the same image. However, such a state places a significant burden on the wearer US, and for example, if the wearer views the image for a long time, the wearer US may be greatly fatigued. In particular, the influence of the misalignment in the up-down direction (y direction, vertical direction) exemplified in Column 4 γ4 is large, and it is desirable to reduce it as much as possible. In addition, depending on the viewing conditions, it is desirable to closely match the left-right direction (horizontal direction) exemplified in Column 4 γ4. For example, when performing 3D display by intentionally shifting the convergence, it is necessary to cause an intended amount of misalignment on the left and right from the matched state.

[0031] Furthermore, in addition to the above-mentioned vertical and horizontal image misalignment, image distortion and rotation may also occur, and it may be necessary to correct these as well. It may also be possible to perform corrections while taking into account distortion and rotation that originally occur in the optical system.

[0032] Therefore, in this embodiment, for an optical unit OU that has already been assembled using assembly members AS such as the lens barrels BRa, BRb and case members CSa, CSb, it is possible to adjust (correct) the display state of the first display device 100A and the second display device 100B even after assembly, especially even after other members other than the optical system (for example, a cover-like exterior member 105d, etc.) have been assembled.

[0033] Hereinafter, adjustment of the display state in the virtual image display device 100 after assembly by the assembly member AS will be described with reference to Fig. 7 etc. Fig. 7 is a plan view conceptually showing an example of the virtual image display device 100 in a state in which other members are further attached after the assembly of the optical system constituting the optical unit OU, and Fig. 8 is a plan view conceptually showing adjustment of the display state in the virtual image display device 100 shown in Fig. 7. Fig. 9 is a block diagram for explaining an example of image processing for adjusting the display state under the circumstances of Fig. 8.

[0034] Here, in an example shown in Figure 7 etc., a case will be described in which, as an optical adjustment after assembly of the above optical system, adjustment of the panel display position (adjustment of the display area) on the display surface SSa of the display element 80 is performed by digital adjustment (correction) to enable adjustment of the display state.

[0035] First, FIG. 7 shows an example of the virtual image display device 100 in a state where each part such as a control device (controller) CT is attached after the optical unit OU is assembled. That is, an example of the virtual image display device 100 is shown as a tentatively finished product that can be delivered to an end user (consumer, purchaser). However, in this case, as a result of going through the installation process of each part after the assembly of the optical unit OU, a deviation such as distortion occurs in the optical system constituting the optical unit OU, and this deviation needs to be corrected. That is, after the virtual image display device 100 is assembled into a finished product, the deviation of the left and right image positions caused by the assembly after the assembly of the optical unit OU is corrected.

[0036] 7, the example virtual image display device 100 is provided with a control device CT for performing various controls such as control and output of image information to be displayed and reception of various operation commands from the wearer US, and the first display device 100A and the second display device 100B are connected to the control device CT via cables CB (CBa, CBb). The control device CT is provided with a main control unit MP composed of a CPU and the like, as well as an image branching unit VB, and is provided with a first output unit GOa that outputs image data to the first display device 100A for the right eye and a second output unit GOb that outputs image data to the second display device 100B for the left eye.

[0037] Furthermore, in the illustrated example, the first display device 100A is provided with a first correction unit COa, and the second display device 100B is provided with a second correction unit COb, as a correction circuit unit for adjusting the display state. The first correction unit COa includes a first correction amount memory CMa and a first correction circuit CCa. Similarly, the second correction unit COb includes a second correction amount memory CMb and a second correction circuit CCb. Note that the first display device 100A and the second display device 100B, as well as the first correction unit COa and the second correction unit COb, may be regarded as the optical unit OU. That is, the optical unit OU may include not only optical members but also circuit boards and the like. The optical unit OU including the circuit boards and the like constituting the first correction unit COa and the like may also be a product that is the subject of commercial trading.

[0038] Information on the necessary correction amount can be written into the first and second correction amount memories CMa and CMb, and the first and second correction circuits CCa and CCb correct the image, i.e. adjust the panel display position (adjust the display area), based on the contents recorded in the first and second correction amount memories CMa and CMb. That is, by inputting the necessary correction amount (adjustment amount) into the first and second correction amount memories CMa and CMb, the first and second correction units COa and COb function as a post-assembly adjustment device AA that adjusts the display state of the first display device 100A and the second display device 100B that have undergone a process after the assembly of the optical unit OU. Note that the first and second correction units COa and COb as the post-assembly adjustment device AA perform different conversion processing on one and the other of the video signals branched into two according to the first display device 100A and the second display device 100B after branching. That is, the first correction unit COa and the second correction unit COb perform conversion processing separately and independently.

[0039] Hereinafter, with reference to FIGS. 8 and 9, the adjustment of the display state in the virtual image display 100 illustrated in FIG. 7, that is, the adjustment of the display area (adjustment method) will be described.

[0040] First, as shown in Fig. 8, the display state after the optical system is assembled is adjusted using an adjustment device NA consisting of a pair of image pickup elements (cameras) NCa, NCb and an image processing device NI for the virtual image display device 100 illustrated in Fig. 7. That is, the adjustment device NA measures the correction amounts to be recorded in the first and second correction amount memories CMa, CMb.

[0041] To explain the measurement of the correction amount (measurement of the adjustment amount of the display area) in more detail, first, the image pickup elements NCa and NCb are installed at the formation position of the exit pupil EP assumed as the position of the left and right eyes EY of the wearer US (see FIG. 2, etc.), while a temporary image is displayed from the optical system that has already been assembled and fixed. The image pickup elements NCa and NCb pick up the temporary image, and the imaging result is sent to the image processing device NI. The image processing device NI calculates the deviation of each part of the optical system from the imaging result (corresponding to the visual state of the wearer US) of the image pickup elements NCa and NCb assumed as the left and right eyes. Furthermore, according to the calculation result, the image processing device NI measures the correction amount required for each of the first display device 100A and the second display device 100B (measurement of the adjustment amount of the display area), and the measurement result is output to the first and second correction units COa and COb. That is, information regarding the necessary correction amount (adjustment amount of the display area) is input to the first and second correction amount memories CMa and CMb of the first and second correction units COa and COb.

[0042] FIG. 9 is a block diagram for explaining a more specific example of the first correction unit COa and the second correction unit COb described above. In the illustrated example, the first correction circuit CCa of the first correction unit COa is composed of a right-eye distortion correction unit DCa, a right-eye pixel conversion position adjustment unit PAa, and a right-eye rotation correction unit RCa. The right-eye distortion correction unit DCa is a correction circuit (distortion correction circuit) for correcting distortion caused by the optical system for the entire image to be displayed for the right eye. The right-eye pixel conversion position adjustment unit PAa is an adjustment circuit (conversion position adjustment circuit) for adjusting the conversion position (deviation correction) for the top, bottom, left, and right in pixel units of the display position. The right-eye rotation correction unit RCa is a correction circuit (rotation correction circuit) for correcting rotation caused by the optical system for the entire image to be displayed for the right eye. These appropriately acquire information from a correction amount memory CM, i.e., a first correction amount memory CMa, as necessary. Incidentally, as in the embodiment using the adjustment device NA illustrated in FIG. 8, the correction amount is input in advance as an external input to the correction amount memory CM (first correction amount memory CMa).

[0043] Similarly, with regard to the second correction unit COb, the second correction circuit CCb is composed of a distortion correction unit DCb for the left eye, a pixel conversion position adjustment unit PAb for the left eye, and a rotation correction unit RCb for the left eye, which acquire information appropriately from the correction amount memory CM, i.e., the second correction amount memory CMb, as necessary.

[0044] Hereinafter, various signal processes and image formation based thereon will be briefly described. For example, when a video signal is input to the control device (controller) CT and image data (video signals) for the left and right corresponding to the video signal are output from the video branching unit VB, in the first correction unit COa for the right eye, first, the distortion correction unit DCa for the right eye performs distortion correction on the entire image, then the pixel position is adjusted in the pixel conversion position adjustment unit PAa for the right eye, and finally, the rotation correction unit RCa for the right eye performs rotation correction on the entire image. The image data (video signals) that have undergone the above-mentioned processes are output to the display driver DDa for the right eye that constitutes the display element 80a, and the image light ML corresponding to the image data (video signals) is emitted from the OLED panel OPa for the right eye that also constitutes the display element 80a.

[0045] It should be noted that the second correction unit COb for the left eye, the OLED panel OPb for the left eye constituting the display element 80b, and the OLED panel OPb for the left eye function in the same manner with respect to image formation for the left eye.

[0046] In addition, in the above description, for convenience of explanation, the first correction circuit CCa is composed of three elements, namely, a distortion correction unit DCa for the right eye, a pixel conversion position adjustment unit PAa for the right eye, and a rotation correction unit RCa for the right eye, but in reality, the first correction circuit CCa can be composed of one chip (circuit) that performs processing corresponding to these. The same is true for the second correction circuit CCb of the second correction unit COb.

[0047] Hereinafter, a specific embodiment of the adjustment process of the video signal will be described with reference to a conceptual diagram of the display surface SSa of the display element 80 illustrated in FIG. 10. Here, as an example, the input video signal (screen resolution) is 1920×1080 (FHD), and the display area on the display surface SSa of the display element 80 corresponding to this is the display area IM. In contrast, the number of effective pixels of the panel on the display surface SSa of the display element 80 is 1960×1120=(1920+40)×(1080+40). That is, in the figure, the display effective area IME indicating the maximum area of ​​the display surface SSa of the display element 80 is wider than the display area IM of the display element 80 corresponding to the input video signal, and a margin area MD for adjustment of ±20 pixels is provided on the top, bottom, left and right. In other words, the display area IM of the display element 80 is narrower than the display effective area IME of the display element 80, and the display element 80 has a margin area MD for making the display area IM variable in the display effective area IME. In the above-described configuration, the first and second correction units COa, COb serving as the post-assembly adjustment device AA, for example in the right-eye and left-eye pixel conversion position adjustment units PAa, PAb, are capable of adjusting the position of the virtual image to be viewed not only in the X direction (left-right direction, horizontal direction), which is the first direction in which the first display device 100A and the second display device 100B are aligned, but also in the Y direction (up-down direction, vertical direction), which is the second direction intersecting the X direction.

[0048] In the illustrated example, the margin area MD in each direction is set so that the display position of the effective display area IME can be shifted by adding 10 pixels above, 30 pixels below, 5 pixels to the left, and 35 pixels to the right to the display area IM when the original video signal is in the standard position. In this embodiment, as described with reference to FIG. 4 and the like, positioning is performed in a panel adjustment process in which the case members CSa and CSb are attached to the lens barrels BRa and BRb, and the display area IM is aligned to the standard position at the time of positioning. In order to enable the above-mentioned processing, the first and second correction units COa and COb as the post-assembly adjustment device AA have a video processing circuit that converts the input video signal and outputs it to the display element 80, and in particular, includes an enlargement processing circuit that converts (performs resolution conversion) into a video signal with a larger number of pixels than the input video signal, that is, into a video signal corresponding to the effective display area IME in the display element 80.

[0049] In this embodiment, in addition to the above-mentioned misalignment correction in the up, down, left, and right directions using each margin, rotation adjustment, etc. are also performed, and in this case, if information at the end of the image is cut off due to the rotation, etc., it may be displayed in a cut-off state. Alternatively, for example, a limit may be set on the rotation, etc. depending on the position shift amount (misalignment correction amount). In other words, the first and second correction units COa and COb as the post-assembly adjustment device AA may be configured to perform at least one of a parallel movement of the display position and a rotation of the display position, or both, within the range of the number of pixels of the video signal increased by the conversion in the enlargement processing circuit.

[0050] Moreover, the amount of adjustment (±20 pixels) that can be handled as the deviation correction in the above case corresponds to about ±0.3° up, down, left, and right when converted into deviation of the optical axis (angle deviation). On the other hand, the amount of adjustment during positioning in each process of assembling the optical system, such as the panel adjustment process described with reference to Figures 4 and 5, can be set to allow, for example, an adjustment of about ±3° up, down, left, and right in terms of the optical axis angle. In other words, the adjustment amount during assembly using the assembly members AS of the lens barrels BRa, BRb, etc. is greater than the adjustment amount during re-adjustment in the first and second correction units COa, COb as the post-assembly adjustment device AA.

[0051] In the above, the lens barrels BRa, BRb, etc., as the mounting members AS, are physical position adjustments that adjust the relative positions of the display elements 80a, 80b and the light guide systems 90a, 90b while mounting, and the first and second correction units COa, COb, as the post-assembly adjustment device AA, are electronic position adjustments by digital processing (image processing) that adjust the display areas of the display elements 80a, 80b. Note that the virtual image display device 100 can be a product that is the subject of commercial trading regardless of whether or not it is adjusted by the post-assembly adjustment device AA, and the manufacturing process (one step in the manufacturing method) of the virtual image display device 100 may or may not include adjustment by the post-assembly adjustment device AA.

[0052] As described above, the virtual image display device 100 according to the present embodiment includes the first display device 100A for the right eye, the second display device 100B for the left eye, the lens barrels BRa, BRb, etc., as the assembly members AS for assembling the first display device 100A and the second display device 100B, and the first and second correction units COa, COb as the post-assembly adjustment device AA for adjusting the display state of the first display device 100A and the second display device 100B assembled by the assembly members AS. In the virtual image display device 100, even if a new image position shift occurs between the left and right after the first display device 100A and the second display device 100B are assembled by the assembly members AS such as the lens barrels BRa, BRb, the shift can be corrected by adjusting the display state of the first display device 100A and the second display device 100B by the first and second correction units COa, COb as the post-assembly adjustment device AA.

[0053] Hereinafter, a modified example of the virtual image display device 100 according to the present embodiment will be described with reference to an external perspective view shown in FIG. 11. In this modified example, the first display device 100A and the second display device 100B are separate and independent, and the first display device 100A and the second display device 100B are connected via a frame 102. In this respect, that is, in that the frame 102 functions as an assembly member AS for assembling the optical system constituting the first display device 100A and the optical system constituting the second display device 100B, it is different from the embodiment illustrated in FIG. 1 and the like in which the optical system is connected by the see-through light guide unit 100C to form an integrated member. Even in this case, it is possible to perform the assembly of the optical system (optical unit OU) with high accuracy, and even if a new deviation in image position between the left and right occurs after the assembly of the optical system (optical unit OU), the deviation can be corrected.

[0054] Second Embodiment Hereinafter, the virtual image display device according to the second embodiment will be described with reference to Fig. 12. Note that this embodiment is similar to the first embodiment except for a part of the image processing content for adjusting the display state after the optical system is assembled, and the overall appearance is similar to that described with reference to Fig. 1 in the first embodiment, so illustrations are omitted and the above-mentioned figures are to be referred to as appropriate as necessary.

[0055] FIG. 12 is a block diagram illustrating an example of image processing for adjusting the display state in the virtual image display device of this embodiment, and corresponds to FIG.

[0056] As is clear when compared with Figure 9, the example shown in Figure 12 differs from the first embodiment in that, of the first correction unit COa and the second correction unit COb, the first correction circuit CCa and the second correction circuit CCb are provided with a right eye reduction correction unit SRa and a left eye reduction correction unit SRb.

[0057] For example, in one aspect exemplified in the first embodiment, as described with reference to Fig. 10, the display area IM corresponding to the input video signal is narrower than the effective display area IME of the display surface SSa, and a margin area MD is provided to make the display area IM variable. From another perspective, the input video signal corresponds to 1920 x 1080 (FHD), while the number of effective pixels in the display element 80 is 1960 x 1120, which is larger than the input video signal, making it possible to provide the margin area MD.

[0058] However, there may be cases where the display element 80 used is equivalent to, for example, 1920×1080 (FHD) like the input video signal. In such cases, it may not be possible to secure a sufficient area equivalent to the margin area MD in Fig. 10, and if position adjustment or rotation adjustment is performed as a correction, there is a possibility that information at the edge of the screen will be largely lost.

[0059] In contrast to this, in the present embodiment, the first correction unit COa and the second correction unit COb as the image processing circuits are provided with a right-eye reduction correction unit SRa and a left-eye reduction correction unit SRb, and by performing reduction processing in advance to provide a margin on the periphery, position adjustment and rotation adjustment are possible without causing information loss, thereby making it possible to prevent such information loss. That is, in the present embodiment, the first and second correction units COa and COb as the post-assembly adjustment device AA are configured to include the right-eye and left-eye reduction correction units SRa and SRb as reduction processing circuits that convert the input video signal into a video signal with a smaller number of pixels than the number of pixels of the effective display area IME of the display element 80 (perform resolution conversion) as the image processing circuit.

[0060] In the example of Fig. 12, for example, among the parts constituting the first correction unit COa, first, the distortion correction unit DCa for the right eye performs distortion correction on the entire image, then the right eye reduction correction unit SRa performs reduction processing, and then the pixel position is adjusted by the right eye pixel conversion position adjustment unit PAa, and finally, the right eye rotation correction unit RCa performs rotation correction on the entire image. The same process is also performed in the second correction unit COb provided with the left eye reduction correction unit SRb.

[0061] In the above embodiment, for example, the first and second correction units COa, COb as the post-assembly adjustment device AA may perform at least one of a parallel translation of the display position and a rotation of the display position, or both, within the range of the difference between the number of pixels of the video signal reduced by conversion in the right eye and left eye reduction correction units SRa, SRb, which are reduction processing circuits, and the number of pixels of the effective display area IME in the display element 80.

[0062] In this embodiment as well, even if a new misalignment in the image position between the left and right occurs after assembly of the optical system (optical unit OU), the misalignment can be corrected by adjusting the display state of the first display device 100A and the second display device 100B using the first and second correction units COa and COb as the post-assembly adjustment device AA.

[0063] Third Embodiment Hereinafter, the virtual image display device according to the third embodiment will be described with reference to Fig. 13 and the like. Fig. 13 is an external perspective view for explaining an overview of the virtual image display device 300 of this embodiment, and Fig. 14 is a side cross-sectional view for explaining an example of the internal structure of the virtual image display device 300. Fig. 15 is a conceptual diagram for explaining correction of distortion and rotation occurring in the virtual image display device 300.

[0064] 13 and 14, this embodiment is different from the first embodiment in which light is guided in the lateral direction (X direction, horizontal direction) in that light is guided in the longitudinal direction (Y direction, vertical direction). Meanwhile, the post-assembly adjustment device AA in this embodiment is similar to the first and second correction units COa, COb (see FIG. 8, etc.) illustrated in the first embodiment, etc., and therefore a detailed description thereof will be omitted.

[0065] 13, the virtual image display device 300 in this embodiment has a first display device 300A for the right eye, a second display device 300B for the left eye, and a bridge portion 302 as a support member connecting them at the center. That is, the bridge portion 302 functions as an assembly member AS for assembling the optical system constituting the first display device 300A and the optical system constituting the second display device 300B together.

[0066] Since the first display device 300A and the second display device 300B are optically symmetrical (mirror symmetrical) and have the same structure, FIG. 14 shows only the first display device 300A, and the illustration and description of the second display device 100B are omitted.

[0067] 14, in the virtual image display device 300 of the present embodiment, the first display device 300A for the right eye includes, as optical elements, a display element 380 and a light guide system 390. The light guide system 390 guides the image light ML from the display element 380 to the position where the exit pupil EP is formed.

[0068] The display element 380 is similar to the display element 80 of the first embodiment and the like, and therefore a description thereof will be omitted here, and matters related to its shape will be described later.

[0069] The light guide system 390 includes a projection optical system 321, a prism 322, and a see-through mirror 323. The projection optical system 321 collects the image light ML emitted from the display element 380 into a state close to a parallel light beam. In the illustrated example, the projection optical system 321 is a single lens, and has an entrance surface and an exit surface. The prism 322 has an entrance surface, an internal reflection surface, and an exit surface, and refracts the image light ML emitted from the projection optical system 321 while making it enter the entrance surface, totally reflects it at the internal reflection surface, and refracts it while making it exit from the exit surface. The see-through mirror 323 reflects the image light ML emitted from the prism 322 toward an exit pupil EP. The exit pupil EP is a position where the image light from each point on the display surface SSa is incident so as to be superimposed from an angle direction corresponding to the position of each point on the display surface SSa in a predetermined divergent state or parallel state. The illustrated light guide system 390 has a field of view (FOV) of 44°. The display area of ​​a virtual image by the light guide system 390 is rectangular, and the 44° is in the diagonal direction.

[0070] The projection optical system 321 and the prism 322 are housed in a case 51 together with a display element 380. The case 51 is formed of a light-shielding material, and includes a drive circuit (not shown) for operating the display element 380. The opening of the case 51 has a size that does not block the image light ML traveling from the prism 322 to the see-through mirror 323. The opening of the case 51 can be covered with a light-transmitting protective cover rather than being a simple opening. The see-through mirror 323 is supported by the case 51 via a support plate 54. The case 51 or the support plate 54 is supported by a bridge portion 302 (see FIG. 13), and the support plate 54 and the see-through mirror 323 form an exterior member 303. An inner lens 331 is disposed behind the see-through mirror 323.

[0071] The light guide system 390 is an off-axis optical system. That is, the projection optical system 321, the prism 322, and the see-through mirror 323 constituting the light guide system 390 are arranged to form an off-axis optical system. The fact that the light guide system 390 is an off-axis optical system means that the optical path is bent as a whole before and after the light ray is incident on at least one reflecting surface or refracting surface in the optical elements 321, 322, and 323 constituting the light guide system 390. In addition, the optical axis AX of the light guide system 390, which is an off-axis optical system as described above, is arranged in a Z-shape when viewed in cross section. That is, in the figure, the optical path from the projection optical system 321 to the internal reflecting surface, the optical path from the internal reflecting surface to the see-through mirror 323, and the optical path from the see-through mirror 323 to the exit pupil EP are arranged to be folded back in two stages in a Z-shape.

[0072] In the drawing, the intermediate image MM is formed between the prism 322 and the see-through mirror 323.

[0073] The exit pupil EP is also subjected to the external light HL that has passed through the see-through mirror 323. That is, the wearer US wearing the virtual image display device 300 can observe a virtual image formed by the image light ML superimposed on an external image.

[0074] In particular, in the virtual image display device 300 as described above, distortion occurs due to the light guide system 390 configured by an off-axis optical system. In this embodiment, the first and second correction units COa and COb (see FIG. 8, etc.) of the post-assembly adjustment device AA perform correction that also takes into account the distortion occurring in the light guide system 390. Specifically, as conceptually shown in FIG. 15, a series of processes are performed to perform correction that generates an inverse distortion so as to cancel the generated aberration (distortion). In other words, the first and second correction units COa and COb as distortion correction circuits perform distortion correction that cancels the distortion formed by the light guide system 390. First, in FIG. 15, when an image in the display area IM shown in the first state M1 shown in the first column δ1 is used as the original image, distortion correction is performed on the image, and the display area IM in the effective display area IME becomes the second state M2 shown in the second column δ2. In the second state M2, the image is inverted vertically and horizontally with respect to the original image in the first state M1, taking into account inversion in the optical system. From the second state M2, further resolution conversion (e.g., reduction conversion, etc.) is performed, resulting in the third state M3 shown in the third column δ3. Further rotation correction is performed, resulting in the fourth state M4 shown in the fourth column δ4, and finally translation is performed to reach the fifth state M5 shown by the dashed line in the fifth column δ5.

[0075] As a modified example of the above, the distortion correction units DCa, DCb for the right eye and the left eye serving as distortion correction circuits for canceling out the distortion formed by the light guide system 390 may perform correction to different degrees depending on the wavelength band of the image light HL to be emitted from the display element 80. That is, as in the sixth state M6 shown in the sixth column δ6 corresponding to the second state M2 shown in the second column δ2 in Fig. 15, the degree of distortion correction of the display regions IMa, IMb, IMc corresponding to the red (R), green (G), and blue (B) wavelength bands of the image light HL may differ.

[0076] As described above, in this embodiment, even if a new misalignment in the image position between the left and right occurs after the optical system is assembled with high precision using the bridge portion 302 as the assembly member AS, the misalignment can be corrected by adjusting the display state of the first display device 300A and the second display device 300B using the post-assembly adjustment device AA.

[0077] [Modifications and Others] The present invention has been described above based on the embodiments, but the present invention is not limited to the above embodiments and can be embodied in various forms without departing from the spirit of the present invention. For example, the following modifications are also possible.

[0078] In the above-mentioned embodiments, the post-assembly adjustment device AA that adjusts the display state after assembly by the assembly member AS is shown to be performed by image processing (electronic processing) using a correction circuit such as the first and second correction units COa and COb, but the post-assembly adjustment device AA constituting the virtual image display device 100, 300, etc. is not limited to the above, and various forms are considered to be possible. For example, in combination with the first and second correction units COa and COb, or instead of this, a mechanism capable of centering, such as a jig JG as exemplified in FIG. 16, may be provided to perform correction as post-assembly adjustment using a physical mechanism. Note that FIG. 16 is a diagram corresponding to FIG. 14, and in one example of FIG. 16, in the state shown in FIG. 14, the jig JG abuts against a side of the projection optical system 321 that does not have an optical function, enabling centering of the projection optical system 321.

[0079] Furthermore, in the above, the first and second correction amount memories CMa, CMb and the first and second correction circuits CCa, CCb constituting the first and second correction units COa, COb as the post-assembly adjustment device AA can be in various forms. For example, in the above example, these are provided separately on the left and right, but they may be stored in one memory without being separated on the left and right. In addition, the first and second correction amount memories CMa, CMb and the first and second correction circuits CCa, CCb may be configured by memories or circuits shared with other various memories provided in the virtual image display device 100, for example. In addition to providing these inside the display devices 100A, 100B of the virtual image display device 100, forms in which they are provided in various places are considered. For example, a configuration in which they are provided in the control device (controller) CT illustrated in FIG. 7, etc. is also considered.

[0080] In addition, while the lens barrel BR, case member CS, frame 102, and bridge portion 302 are shown above as examples of the assembly member AS, various assembly members AS that enable assembly between the first display device 100A etc. and the second display device 100B etc. can be used. For example, even in the case of an optical system that does not have a lens barrel etc. and is composed of a prism, a fixing member or adhesive member for positioning the prism can be said to correspond to the assembly member AS. In addition, for example, a joint portion when joining multiple prisms etc. can also be said to correspond to the assembly member AS.

[0081] In the above, for example, the adjustment margin MD is set to ±20 pixels in the up, down, left and right directions, but various other aspects are possible for the adjustment margin. For example, the number of margins may be different in the up and down direction (y direction, vertical direction) and the left and right direction (x direction, horizontal direction), that is, the possible adjustment amount may be different. For example, when an optical system is formed by an integrated member having the see-through light guide unit 100C shown in FIG. 1 or the like, or when the optical system is assembled by the bridge portion 302 shown in FIG. 13, if a torsional stress or the like occurs in each process after the assembly of the optical system, a larger deviation may occur in the up and down direction (y direction) than in the left and right direction (x direction). On the other hand, as described with reference to FIG. 6, the deviation in the up and down direction (y direction), i.e., the vertical direction, has a larger effect, and there are cases where it is strong to want to reduce it as much as possible. Therefore, for example, it is possible to make the correction amount in the up and down direction (y direction, vertical direction) larger than the correction amount in the left and right direction (x direction, horizontal direction).

[0082] Furthermore, in the third embodiment, an optical system having a rotationally asymmetric axis has been described. However, the present invention can also be applied to an optical system having a rotationally symmetric axis, for example, a so-called birdbath type.

[0083] In addition, a dimming device that adjusts light by restricting transmitted light can be attached to the outside world side of the first and second virtual image forming optical units 101a, 101b and the see-through mirror 323. The dimming device adjusts the transmittance, for example, electrically. As the dimming device, a mirror liquid crystal, an electronic shade, etc. can be used. The dimming device may adjust the transmittance according to the illuminance of outside light. When the outside light is blocked by the dimming device, only the virtual image that is not affected by the outside image can be observed. In addition, the virtual image display device of the present invention can be applied to a so-called closed-type head-mounted display device (HMD) that blocks outside light and allows only image light to be viewed. In this case, it may be made to correspond to a so-called video see-through product composed of a virtual image display device and an imaging device.

[0084] In the above description, it is assumed that the virtual image display devices 100 and 300 are used by being mounted on the head, but the virtual image display devices 100 and 300 can also be used as handheld displays that are not mounted on the head and are peered into like binoculars. In other words, in the present invention, the head mounted display also includes a handheld display.

[0085] Also, among the above, for example, it is conceivable to configure the optical axis (emission optical axis) AX to extend at an angle of about 10° downward with respect to the forward +Z direction. By orienting the optical axis AX downward at about 10° on the forward side with respect to the horizontal Z axis, it is possible to reduce eye fatigue of the wearer US who observes the virtual image. In this case, the shape of the display element 80 can be appropriately changed as necessary for correction on the panel side.

[0086] In one specific embodiment, the virtual image display device includes a first display device for the right eye, a second display device for the left eye, an assembly member for assembling the first display device and the second display device, and a post-assembly adjustment device for adjusting the display state of the first display device and the second display device assembled by the assembly member.

[0087] In the above-mentioned virtual image display device, even if a new misalignment in the image position between the left and right displays occurs after the first display device and the second display device are assembled using the assembly members, the misalignment can be corrected by adjusting the display state of the first display device and the second display device using the post-assembly adjustment device.

[0088] In a specific aspect, the assembly member adjusts the relative left and right posture when the first display device and the second display device are assembled together. In this case, the assembly member can adjust the relative left and right misalignment to provide a balanced view between the left and right.

[0089] In another aspect, the adjustment amount during assembly using the assembly members is larger than the adjustment amount during re-adjustment by the post-assembly adjustment device. In this case, the assembly members are adjusted to include large deviations to perform highly accurate adjustment, and then the re-adjustment by the post-assembly adjustment device is performed in a manner similar to fine adjustment.

[0090] In yet another aspect, the first display device and the second display device include a panel-type display element and a light guide system that guides image light emitted from the display element, the assembly member assembles the display elements while adjusting the relative positions of the display element and the light guide system, and the post-assembly adjustment device adjusts the display area of ​​the display element. In this case, even if a deviation occurs in the position adjustment during another manufacturing process after the assembly member adjusts the relative position of the light guide system with respect to the panel-type display element, the deviation can be corrected by adjusting the display area of ​​the panel-type display element in the post-assembly adjustment device.

[0091] In still another aspect, the display area of ​​the display element is narrower than the effective display area of ​​the display element, the display element has a margin area in the effective display area for making the display area variable, and the post-assembly adjustment device has a video processing circuit that converts an input video signal and outputs it to the display element. In this case, image processing is possible using the margin area formed by the difference between the effective display area and the display area.

[0092] In still another aspect, the post-assembly adjustment device includes, as a video processing circuit, an enlargement processing circuit that converts an input video signal into a video signal having a larger number of pixels than the input video signal. In this case, the input video signal can be converted into a video signal corresponding to the effective display area of ​​the display element.

[0093] In still another aspect, the post-assembly adjustment device either translates the display position or rotates the display position within the range of the number of pixels of the video signal increased by the conversion in the enlargement processing circuit. In this case, for example, image loss and the like caused by image processing in the post-assembly adjustment device can be suppressed or avoided.

[0094] In still another aspect, the post-assembly adjustment device includes, as a video processing circuit, a reduction processing circuit that converts an input video signal into a video signal having a smaller number of pixels than the number of pixels of the effective display area of ​​the display element. In this case, a margin area for image processing in the post-assembly adjustment device can be secured.

[0095] In yet another aspect, the post-assembly adjustment device either translates the display position or rotates the display position within a range of the difference between the number of pixels of the video signal reduced by conversion in the reduction processing circuit and the number of pixels of the effective display area of ​​the display element. In this case, for example, image loss and the like caused by image processing in the post-assembly adjustment device can be suppressed or avoided.

[0096] In still another aspect, the post-assembly adjustment device performs different conversion processing on one of the two video signals split into two depending on the first display device and the second display device, in which case the conversion processing is adapted to each of the first display device and the second display device.

[0097] In yet another aspect, the image processing circuit includes a distortion correction circuit that performs distortion correction to offset distortion caused by the light guide system, and the distortion correction circuit performs correction to a different degree depending on the wavelength band of the image light to be emitted from the display element. In this case, correction corresponding to chromatic aberration is possible.

[0098] In yet another aspect, the light guide system includes a projection optical system that converges the image light emitted from the display element, a prism that refracts the image light emitted from the projection optical system while making it incident on an entrance surface, totally reflects the image light on an internal reflection surface, and refracts the image light while making it exit from an exit surface, and a see-through mirror that reflects the image light emitted from the prism toward a pupil position and transmits external light. In this case, the see-through mirror, the projection optical system, and the prism can further improve the optical performance while making the device more compact.

[0099] In yet another aspect, a Z-shaped optical path is formed by folding the light in two stages, first at the internal reflection surface of the prism and then at the see-through mirror. In this case, by folding the light path in a Z shape, it is possible to reduce the size of the device.

[0100] In yet another aspect, the light guide system forms an off-axis optical system, in which case the optical system can be made compact, and thus the entire device can be made compact, while maintaining the resolution.

[0101] In still another aspect, the post-assembly adjustment device adjusts the position of the virtual image to be viewed in a second direction intersecting with a first direction in which the first display device and the second display device are aligned. In this case, the display position of the virtual image can be adjusted in the direction in which the first display device and the second display device are aligned, that is, in the vertical direction relative to the horizontal direction in which the observer's eyes are aligned.

[0102] In one specific embodiment, the optical unit includes a first display device for the right eye, a second display device for the left eye, an assembly member for assembling the first display device and the second display device, and a post-assembly adjustment device for adjusting the display state of the first display device and the second display device assembled by the assembly member.

[0103] In the above optical unit, even if a new misalignment in the image position between the left and right displays occurs after the first display device and the second display device are assembled using the assembly members, the misalignment can be corrected by adjusting the display state of the first display device and the second display device using the post-assembly adjustment device.

[0104] In one specific embodiment, the adjustment method for a virtual image display device is a method for adjusting a virtual image display device having a first display device for the right eye and a second display device for the left eye, and adjusts the display state of the assembled first display device and second display device while adjusting the left and right postures.

[0105] In the above adjustment method, even if a misalignment in the image position between the left and right sides occurs after the first and second display devices are assembled while their left and right postures are adjusted, the misalignment can be corrected by adjusting the display state of the first and second display devices.

[0106] In one specific embodiment, a manufacturing method for a virtual image display device includes a first display device for the right eye and a second display device for the left eye, in which the first display device and the second display device are assembled while adjusting their left-right postures, and the display state of the assembled first display device and second display device is adjusted.

[0107] In the above manufacturing method, even if a misalignment in the image position between the left and right sides occurs after the first and second display devices are assembled while adjusting their left and right postures, it is possible to manufacture a virtual image display device that can correct the misalignment by adjusting the display state of the first display device or the second display device. [Explanation of symbols]

[0108] 10, 10a, 10b...light guiding member, 13...display control circuit, 30, 30a, 30b...projection lens, 50...central member, 50A, 50B...light transmitting portion, 51...case, 51a...opening, 52...protective cover, 54...support plate, 80, 80a, 80b...display element, 90, 90a, 90b...light guiding system, 100...virtual image display device, 100A...first display device, 100B...second display device, 100C...see-through type light guiding unit, 101a...first virtual image forming optical portion, 101b...second virtual image forming optical portion, 102...frame, 105a...first image forming main body portion, 10 5b...second image forming main body portion, 105d...exterior member, 300...virtual image display device, 302...bridge portion, 303...exterior member, 321...projection optical system, 321, 322, 323...optical element, 322...prism, 323...see-through mirror, 331...inner lens, 380...display element, 390...light guide system, AA...post-assembly adjustment device, AS...assembly member, AX...optical axis, BR, BRa, BRb...lens barrel, CB, CBa, CBb...cable, CCa...first correction circuit, CCb...second correction circuit, CM...correction amount memory, CMa...first correction amount memory , CMb...second correction amount memory, COa...first correction unit, COb...second correction unit, CS, CSa, CSb...case member, CT...control device, DCa, DCb...distortion correction unit, DDa, DDb...display driver, DG...recessed portion, EP...exit pupil, EY...eye, EYa...right eye, EYb...left eye, FA...adjustment device, FCa, FCb...imaging element, FI...image processing device, HL...external light, HL...image light, IM...display area, IM1, IM2...image, IMA...image, IME...effective display area, IMa, IMb, IMc...display area, J G...jig, M1 to M4...state, MD...margin area, ML...image light, MM...intermediate image, MP...main control unit, NA...adjustment device, NCa, NCb...imaging element, NI...image processing device, OPa, OPb...OLED panel, OU...optical unit, PAa, PAb...pixel conversion position adjustment unit, PR...protrusion, RCa, RCb...rotation correction unit, SRa, SRb...reduction correction unit, SSa...display surface, US...wearer, VB...image branching unit, α1...upper column, α2...lower column, β1...upper column, β2...lower column, γ1 to γ4...first to fourth columns, δ1 to δ6...first to sixth columns

Claims

1. a first display device for a right eye; a second display device for the left eye; and an assembly member for assembling the first display device and the second display device; a post-assembly adjustment device that adjusts a display state of the first display device and the second display device assembled by the assembly member; Equipped with the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; A display area of ​​the display element is narrower than an effective display area of ​​the display element, the display element has a margin area in the effective display area for making the display area variable, The post-assembly adjustment device includes, as a video processing circuit that converts an input video signal for adjusting the display area of ​​the display element and outputs the converted video signal to the display element, either an enlargement processing circuit that converts the input video signal into a video signal with a larger number of pixels than the input video signal and outputs the video signal to the display element, or a reduction processing circuit that converts the input video signal into a video signal with a smaller number of pixels than the number of pixels of the effective display area of ​​the display element. Virtual image display device.

2. The virtual image display device according to claim 1 , wherein an adjustable amount during assembly by said assembly member is larger than an adjustable amount in re-adjustment by said post-assembly adjustment device.

3. 3. The virtual image display device according to claim 1, wherein the post-assembly adjustment device performs either a translation of a display position or a rotation of a display position within a range of a pixel number of the video signal enlarged by the conversion in the enlargement processing circuit.

4. The virtual image display device according to any one of claims 1 to 3, wherein the post-assembly adjustment device performs either a parallel translation of the display position or a rotation of the display position within a range of the difference between the number of pixels of the video signal reduced by conversion in the reduction processing circuit and the number of pixels of the effective display area of ​​the display element.

5. a first display device for a right eye; a second display device for the left eye; and an assembly member for assembling the first display device and the second display device; a post-assembly adjustment device that adjusts a display state of the first display device and the second display device assembled by the assembly member; Equipped with the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; A display area of ​​the display element is narrower than an effective display area of ​​the display element, the display element has a margin area in the effective display area for making the display area variable, the post-assembly adjustment device has a video processing circuit that converts an input video signal and outputs the converted video signal to the display element in order to adjust the display area of ​​the display element, the video processing circuit performs different conversion processes on one of the video signals branched into two in accordance with the first display device and the second display device, and Virtual image display device.

6. a first display device for a right eye; a second display device for the left eye; and an assembly member for assembling the first display device and the second display device; a post-assembly adjustment device that adjusts a display state of the first display device and the second display device assembled by the assembly member; Equipped with the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; A display area of ​​the display element is narrower than an effective display area of ​​the display element, the display element has a margin area in the effective display area for making the display area variable, the post-assembly adjustment device has a video processing circuit that converts an input video signal and outputs the converted video signal to the display element in order to adjust the display area of ​​the display element, the image processing circuit includes a distortion correction circuit that performs distortion correction to offset distortion caused by the light guide system; the distortion correction circuit performs correction to a different degree depending on a wavelength band of the image light to be emitted from the display element. Virtual image display device.

7. a first display device for a right eye; a second display device for the left eye; and an assembly member for assembling the first display device and the second display device; a post-assembly adjustment device that adjusts a display state of the first display device and the second display device assembled by the assembly member; Equipped with the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; the post-assembly adjustment device has a video processing circuit that converts an input video signal and outputs the converted video signal to the display element in order to adjust a display area of ​​the display element, the light guide system includes a projection optical system that converges the image light emitted from the display element, a prism that refracts the image light emitted from the projection optical system while making it incident on an entrance surface, totally reflects the image light on an internal reflection surface, and refracts the image light while making it exit from an exit surface, and a see-through mirror that reflects the image light emitted from the prism toward a pupil position and transmits external light. Virtual image display device.

8. 8. The virtual image display device according to claim 7, wherein a Z-shaped optical path is formed by folding light in two stages, first at the internal reflection surface of the prism and then at the see-through mirror.

9. The virtual image display device according to claim 7 , wherein the light guide system forms an off-axis optical system.

10. 1. A method for adjusting a virtual image display device including a first display device for a right eye and a second display device for a left eye, comprising the steps of: A method for adjusting a virtual image display device, comprising adjusting a display state of the first display device and the second display device that are assembled while adjusting a left-right attitude, the method comprising: the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; A display area of ​​the display element is narrower than an effective display area of ​​the display element, the display element has a margin area in the effective display area for making the display area variable, a video processing circuit that converts an input video signal for adjusting the display area of ​​the display element and outputs the converted video signal to the display element, converting the input video signal into a video signal with a larger number of pixels than the input video signal and outputting the video signal to the display element, or converting the input video signal into a video signal with a smaller number of pixels than the number of pixels of the effective display area of ​​the display element; A method for adjusting a virtual image display device.

11. 1. A method for adjusting a virtual image display device including a first display device for a right eye and a second display device for a left eye, comprising the steps of: A method for adjusting a virtual image display device, comprising adjusting a display state of the first display device and the second display device that are assembled while adjusting a left-right attitude, the method comprising: the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; A display area of ​​the display element is narrower than an effective display area of ​​the display element, the display element has a margin area in the effective display area for making the display area variable, a video processing circuit that converts a video signal input for adjusting the display area of ​​the display element and outputs the converted video signal to the display element, and performs different conversion processing on one of the video signals branched into two in accordance with the first display device and the second display device; A method for adjusting a virtual image display device.

12. 1. A method for adjusting a virtual image display device including a first display device for a right eye and a second display device for a left eye, comprising the steps of: A method for adjusting a virtual image display device, comprising adjusting a display state of the first display device and the second display device that are assembled while adjusting a left-right attitude, the method comprising: the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; A display area of ​​the display element is narrower than an effective display area of ​​the display element, the display element has a margin area in the effective display area for making the display area variable, a video processing circuit that converts a video signal input for adjusting the display area of ​​the display element and outputs the converted video signal to the display element, and performs distortion correction to offset the distortion caused by the light guide system to a different degree depending on the wavelength band of the image light to be emitted from the display element; A method for adjusting a virtual image display device.

13. 1. A method for adjusting a virtual image display device including a first display device for a right eye and a second display device for a left eye, comprising the steps of: A method for adjusting a virtual image display device, comprising adjusting a display state of the first display device and the second display device that are assembled while adjusting a left-right attitude, the method comprising: the first display device and the second display device each include a panel-type display element and a light guide system that guides image light emitted from the display element; the light guide system includes a projection optical system that converges the image light emitted from the display element, a prism that causes the image light emitted from the projection optical system to be incident on an entrance surface while refracting the image light, causes total reflection on an internal reflection surface, and causes the image light to be emitted from an exit surface while refracting the image light, and a see-through mirror that reflects the image light emitted from the prism toward a pupil position and transmits external light, In order to adjust the display area of ​​the display element, a video signal input by a video processing circuit is converted and output to the display element. A method for adjusting a virtual image display device.

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