Image display device and manufacturing method thereof

Abstract

To provide an image display device that is not easily affected by the manufacturing tolerance of a support and the assembly tolerance of the support, and a method for manufacturing the same.SOLUTION: An image display device 200 comprises: a first display unit 100a that has a first frame 61a and a first optical system 12a; a second display unit 100b that has a second frame 61b and a second optical system 12b; and a fixing member 78 that fixes the first display unit 100a and the second display unit 100b relative to each other. The fixing member 78 has a shape that allows the first optical system 12a and the second optical system 12b to rotate in directions of two or more axes in alignment before fixing the first display unit 100a and the second display unit 100b.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present invention relates to an image display device that enables viewing of a virtual image and a manufacturing method thereof, and more particularly to an image display device having a display unit for both eyes. [Background technology]

[0002] A virtual image display device in the form of glasses is known in which an optical system for the left eye, which extends from a first display element to a light guide member, and an optical system for the right eye, which extends from a second display element to a light guide member, are mounted on a frame extending in the horizontal direction by means of screws or the like, so that the left and right optical systems are positioned in front of the eyes (Patent Document 1). In this virtual image display device, in order to reduce the effects of manufacturing tolerances and assembly errors, the display element is aligned with the optical system by using a convex portion provided on either the holding member for the display element or the lens barrel of the projection lens, and a concave portion provided on the other. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-211674 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the device of Patent Document 1, the final arrangement of the left eye optical system and the right eye optical system is determined by assembling them in a frame, so there is a possibility that they will be affected by manufacturing tolerances and frame assembly tolerances. [Means for solving the problem]

[0005] An image display device according to one aspect of the present invention includes a first table having a first frame and a first optical system. a second display unit having a second frame and a second optical system; and a second display unit having the first display unit and the second frame and a second optical system. and a fixing member that fixes the display unit relative to the display unit, the fixing member comprising: A pair of connectors on both ends A dumbbell-shaped member having a spherical first fixing portion and a spherical second fixing portion, The first display unit and the second display unit The display unit is fixed in place.

[0006] A manufacturing method for an image display device according to one aspect of the present invention is a manufacturing method for an image display device including a first display unit having a first frame and a first optical system, a second display unit having a second frame and a second optical system, and a fixing member that fixes the first display unit and the second display unit relative to each other, wherein the fixing member has a shape that allows the first optical system and the second optical system to be rotatable in rotational directions about two or more axes, and after alignment, the rotation of the first optical system and the second optical system relative to the fixing member is stopped. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an external perspective view illustrating a mounting state of an image display device according to a first embodiment. [Diagram 2] 1A to 1C are a plan view, a front view, a side view, and a bottom view of an image display device. [Diagram 3] 1A to 1C are a front view, a side view, a perspective view, and the like showing the inside of an image display device with an exterior member removed. [Figure 4] FIG. 2 is an exploded perspective view of the remaining portion of the image display device with the exterior member removed. [Diagram 5] 3A and 3B are a plan view and a bottom view of an optical unit combining the left and right display units. [Figure 6] Shown are an oblique view explaining the connection between the first frame and the fixed member, an oblique view explaining the positional relationship between the fixed member and the first cover member, and an oblique view explaining the positional relationship between the first frame, the fixed member, and the first cover member. [Figure 7] 1 shows a bottom view of an upper exterior member and a plan view of a lower exterior member. [Figure 8] 1 is a conceptual side cross-sectional view illustrating an internal optical system of an image display device. [Figure 9] 11A and 11B are diagrams illustrating correction of distortion of a display image. [Figure 10A]3A to 3C are a front view, a plan view, and a perspective view of a fixing member. [Figure 10B] 5 is a conceptual cross-sectional view illustrating a state in which a fixing member is fixed to a frame. FIG. [Figure 11] 4 is a partially cutaway perspective view illustrating the connection between the first display unit and a fixing member, etc. FIG. [Figure 12A] 6 is an enlarged cross-sectional view illustrating the fixing of a first frame by a first fixing portion. FIG. [Figure 12B] 13 is an enlarged cross-sectional view illustrating the fixing of a second frame by a second fixing portion. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the structure, operation, manufacturing method, etc. of the image display device according to the present invention will be described with reference to FIGS.

[0009] FIG. 1 is a diagram for explaining a wearing state of the image display device 200. The image display device 200 is a head mounted display (hereinafter also referred to as HMD) 201, and allows an observer or wearer US wearing the image display device to recognize an image as a virtual image. In FIG. 1 and the like, X, Y, and Z are an orthogonal coordinate system, and the +X direction corresponds to the lateral direction in which the eyes EY of the observer or wearer US wearing the image display device 200 or HMD 201 are aligned, the +Y direction corresponds to the upward direction perpendicular to the lateral direction in which the eyes EY are aligned for the wearer US, and the +Z direction corresponds to the forward direction or front direction for the wearer US. The ±Y directions are parallel to the vertical axis or vertical direction.

[0010] The image display device 200 includes a main body 200a arranged to cover the front of the eyes of the wearer US, and a pair of temple-shaped support devices 200b that support the main body 200a. From a functional perspective, the main body 200a includes a first display device 100A for the right eye and a second display device 100B for the left eye. The first display device 100A is composed of a display driver 102 arranged at the top and a combiner 103a shaped like a pair of glasses that covers the front of the eyes. The second display device 100B is similarly composed of a display driver 102 arranged at the top and a combiner 103b shaped like a pair of glasses that covers the front of the eyes.

[0011] The appearance of the main body 200a of the image display device 200 will be described with reference to FIG. 2. In FIG. 2, an area AR1 is a plan view of the main body 200a, an area AR2 is a front view of the main body 200a, an area AR3 is a right side view of the main body 200a, and an area AR4 is a bottom view of the main body 200a. A pair of display drive units 102 arranged on the +Y side, i.e., the upper side, of the main body 200a are connected and integrated, and are covered by a dome-shaped upper exterior member 107a elongated in the horizontal direction and a flat plate-shaped lower exterior member 107b. The first combiner 103a and the second combiner 103b have a shape like a hemisphere with the upper part cut out and protruding forward, i.e., in the +Z direction, and are arranged to protrude downward from the lower exterior member 107b.

[0012] With reference to FIG. 3, an outline of the internal structure of the main body 200a shown in FIG. 2 with the upper exterior member 107a and the lower exterior member 107b removed will be described. In FIG. 3, region BR1 is a front view exposing the upper part of the main body 200a, region BR2 is a right side view exposing the upper part of the main body 200a, region BR3 is a perspective view exposing the upper part of the main body 200a, and region BR4 is a perspective view exposing the internal optical system of the main body 200a. The first display device 100A for the right eye includes a first display element 11a, a first optical system 12a, and a first combiner 103a as the first display unit 100a. A first frame 61a described later is also an element of the first display unit 100a. The first optical system 12a is covered by a first cover member 71a, which is an inner cover, and the first display element 11a is positioned so as to cover an opening 71o of the first cover member 71a and is fixed to the outer frame of the first optical system 12a via a rectangular frame-shaped first holder 72a.

[0013] As shown in FIG. 4, the first optical system 12a is fixed to the upper surface of a plate-shaped first frame 61a by adhesive or the like, and the first combiner 103a is fixed at its upper end to the front half of the periphery of the first frame 61a by adhesive or the like.

[0014] Returning to FIG. 3, the second display device 100B includes a second display element 11b, a second optical system 12b, and a second combiner 103b as the second display unit 100b. A second frame 61b, which will be described later, is also an element of the second display unit 100b. The second optical system 12b is covered by a second cover member 71b, which is an inner cover, and the second display element 11b is arranged so as to cover an opening 71o of the second cover member 71b, and is fixed to the outer frame of the second optical system 12b via a rectangular frame-shaped second holder 72b. The second display device 100B for the left eye has the same structure and function as the first display device 100A for the right eye. That is, the second display element 11b is similar to the first display element 11a, the second optical system 12b is similar to the first optical system 12a, and the second combiner 103b is similar to the first combiner 103a. However, when the first optical system 12a, the first combiner 103a, etc. are made asymmetric in the left-right X direction, the second optical system 12b, the second combiner 103b, etc. become the left-right inverted versions of the first optical system 12a, the first combiner 103a, etc.

[0015] As shown in FIG. 4, the second optical system 12b is fixed to the upper surface of a plate-shaped second frame 61b by adhesive or the like, and the second combiner 103b is fixed at its upper end to the front half of the periphery of the second frame 61b by adhesive or the like.

[0016] Returning to FIG. 3, the first display device 100A and the second display device 100B are connected internally via a fixing member 78. The fixing member 78 is a rod-shaped metal member, and is made of, for example, a magnesium alloy. By making the fixing member 78 of a magnesium alloy, it is possible to provide an effect of cooling the first frame 61a and the second frame 61b by dissipating heat. The fixing member 78 fixes the first display unit 100a and the second display unit 100b relatively at both ends. The fixing member 78 is a member equivalent to the arms of a balance, and supports the pair of display units 100a, 100b equivalent to a pair of plates at the center. The fixing member 78 has a shape that allows the first optical system 12a and the second optical system 12b to rotate in two or more rotational directions when aligning the first display unit 100a and the second display unit 100b before fixing them.

[0017] 4 to 6, the support of the first display unit 100a and the second display unit 100b by the fixing member 78 will be described. In FIG. 5, region CR1 is a plan view of the optical unit OU in which the left and right display units 100a and 100b are connected, and region CR2 is a bottom view of the optical unit OU. In FIG. 6, region DR1 is a perspective view explaining the connection between the first frame 61a and the fixing member 78, region DR2 is a perspective view explaining the positional relationship between the fixing member 78 and the first cover member 71a, and region DR3 is a perspective view explaining the positional relationship between the first frame 61a, the fixing member 78, and the first cover member 71a. At both ends of the fixing member 78, fixing parts 81a and 82a, which are spherical members similar to components of a ball joint, are formed, as will be described in detail later. After the first display unit 100a and the second display unit 100b are aligned, the fixing parts 81a and 82a are adhered to the recesses 81b and 82b, which are hemispherical recessed members provided at the inner ends of the display units 100a and 100b or the frames 61a and 61b, by adhesive or the like, and are in a state of being stopped from rotating. As an adhesive for fixing the fixing parts 81a and 82a to the recesses 81b and 82b, a photocurable resin material can be used, but is not limited thereto, and a thermosetting or room temperature curable resin material or the like can be used. The connecting member 81, which combines the fixing part 81a and the recess 81b, is covered by the extension part 71c of the first cover member 71a. The connecting member 82, which combines the fixing part 82a and the recess 82b, is also covered by the extension part 71c of the second cover member 71b.

[0018] The first frame 61a is a semicircular metal member and is made of, for example, a magnesium alloy. By forming the first frame 61a from a magnesium alloy, it is possible to improve the efficiency of dissipating heat generated by the display element 11a and the like. Recesses 81b are formed on both the left and right ends of the first frame 61a, but only one of the recesses 81b is used for connection to the fixing member 78. An optical aperture OA is formed in the first frame 61a, and a plate-shaped optical element 28 that seals the optical aperture OA is disposed therein. The plate-shaped optical element 28 is a part of the first optical system 12a. The second frame 61b is a semicircular metal member and is made of, for example, a magnesium alloy. By forming the second frame 61b from a magnesium alloy, it is possible to improve the efficiency of dissipating heat generated by the display element 11b and the like. Recesses 82b are formed on both the left and right ends of the second frame 61b, but only one of the recesses 82b is used for connection to the fixing member 78. An optical aperture OA is also formed in the second frame 61b, and a plate-shaped optical element 28 that seals the optical aperture OA is disposed therein.

[0019] The upper exterior member 107a and the lower exterior member 107b will be described with reference to FIG. 7. In FIG. 7, an area ER1 is a bottom view showing the inside of the upper exterior member 107a, and an area ER2 is a plan view showing the inside of the lower exterior member 107b. The upper exterior member 107a and the lower exterior member 107b are formed of a resin material. The outer edge 7a of the upper exterior member 107a and the outer edge 7b of the lower exterior member 107b have the same shape, and by butting them together, a space for storing the first optical system 12a and the second optical system 12b shown in FIG. 3 can be formed. The upper exterior member 107a and the lower exterior member 107b are fixed using fastening parts 7f, 7g such as screw holes. The lower exterior member 107b has a pair of openings OP1, and the first frame 61a and the second frame 61b can be arranged in the openings OP1 as shown by dotted lines. A gap GP is provided between the opening OP1 and the frames 61a, 61b, allowing the frames 61a, 61b to be misaligned in the XZ plane and in the Y direction within the opening OP1. In other words, the first display unit 100a and the second display unit 100b shown in FIG. 3 and the like are fixed to the lower exterior member 107b while remaining aligned with each other, and even when stored in the upper exterior member 107a and the lower exterior member 107b, the positional relationship between the two display units 100a, 100b at the time of completing positioning is maintained. A screw hole 7j is formed in the lower exterior member 107b, and the display units 100a, 100b can be fixed to a pair of fastening portions 78z provided on the bridge 78a of the fixing member 78 by screwing.

[0020] 3 and 4, an elastic sheet 75 is disposed above the first frame 61a and the second frame 61b. An outer peripheral portion 75a of the elastic sheet 75 is sandwiched between the outer edge 7a of the upper exterior member 107a and the outer edge 7b of the lower exterior member 107b shown in FIG. 7, enabling airtight or liquidtight sealing between the exterior members 107a, 107b. A pair of openings OP21, OP22 are formed in the elastic sheet 75. An inner peripheral portion 75b around one opening OP21 is disposed so as to be sandwiched between the upper surface of the first frame 61a and the lower end of the first cover member 71a at its inner end, and is sandwiched between the upper surface of the first frame 61a and the lower end of the first cover member 71a at a location corresponding to the outer edge of the first frame 61a. and bonded to the upper surface of the second frame 61b at a location corresponding to the outer edge of the second frame 61b, thereby enabling airtight or liquidtight sealing between the first frame 61a and the first cover member 71a. The inner periphery 75c around the other opening OP22 is disposed so as to be sandwiched between the upper surface of the second frame 61b and the lower end of the second cover member 71b at its inner end, and bonded to the upper surface of the second frame 61b at a location corresponding to the outer edge of the second frame 61b, thereby enabling airtight or liquidtight sealing between the second frame 61b and the second cover member 71b.

[0021] Referring to FIG. 3, a rectangular circuit board 91 is disposed above the fixing member 78 and between the left and right display units 100a and 100b. The circuit board 91 includes a control device 92 that controls the display operation of the first display element 11a and the second display element 11b. The control device 92 outputs drive signals corresponding to display images to the left and right display elements 11a and 11b to control the display operation of the left and right display elements 11a and 11b. The control device 92 includes, for example, an IF circuit, a signal processing circuit, etc., and causes the left and right display elements 11a and 11b to perform two-dimensional image display in response to image data or image signals received from the outside. The control device 92 includes a main board (not shown) that controls the operation of the first display device 100A and the operation of the second display device 100B. The main board may have, for example, an interface function for communicating with an external device (not shown) and converting signals received from the external device, and an integration function for linking the display operation of the first display device 100A with the display operation of the second display device 100B.

[0022] The circuit board 91 is supported on the fixing member 78 by the board support portion 74. The circuit board 91 is fixed on the board support portion 74. The board support portion 74 is a resin member that covers the fixing member 78 from above, the front, and the rear, and is detachable from the fixing member 78 together with the circuit board 91 by snap-fitting using the fitting portion 51.

[0023] FIG. 8 is a side cross-sectional view explaining the optical structure of the first display unit 100a. The first display unit 100a includes a first display element 11a and an imaging optical system 20. The imaging optical system 20 is also called a light guide optical device. The imaging optical system 20 includes a projection lens 21, a prism mirror 22, a plate-shaped optical element 28, and a see-through mirror 23. In the imaging optical system 20, the projection lens 21, the prism mirror 22, and the plate-shaped optical element 28 correspond to the first optical system 12a shown in FIG. 3 and the like, and the see-through mirror 23 corresponds to the first combiner 103a. The first display element 11a, the projection lens 21, and the prism mirror 22 are fixed to the first frame 61a in a state of being mutually aligned by a frame body (not shown), and are housed in a space SP1 sandwiched between the first cover member 71a and the first frame 61a. The plate-shaped optical element 28 is disposed so as to fit into a step formed in the optical aperture OA of the first frame 61a, and the periphery of the optical aperture OA is kept airtight.

[0024] The first display element 11a is a self-luminous display device. The first display element 11a is, for example, an organic EL (organic electroluminescence) display, and forms a color still image or video on a two-dimensional display surface 11d. The first display element 11a is arranged along an xy plane that is rotated and tilted around the X axis with the XY plane as a reference. The first display element 11a is driven by a control device 92 provided on a circuit board 91 to perform a display operation. The first display element 11a is not limited to an organic EL display, and can be replaced with a display device using a micro LED display, inorganic EL, organic LED, laser array, quantum dot light-emitting element, or the like. The first display element 11a 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 first display element 11a, instead of an LCD, LCOS (Liquid crystal on silicon, LCoS is a registered trademark), a digital micromirror device, or the like can also be used.

[0025] The projection lens 21 passes the image light ML emitted from the first display element 11a and makes it enter the prism mirror 22. The projection lens 21 collects the image light ML emitted from the first display element 11a into a state close to a parallel light beam. The projection lens 21 includes a first lens 21p and a second lens 21q. The prism mirror 22 has an inner reflection surface 22b, and makes the image light ML emitted from the projection lens 21 enter the inside from the entrance surface 22a, totally reflects it at the inner reflection surface 22b, and makes it exit from the exit surface 22c. At this time, the prism mirror 22 turns back the image light ML incident from the front and emits it in a direction inclined with respect to the direction in which the incident direction is reversed (the direction of the light source as seen from the prism mirror 22). The plate-shaped optical element 28 refracts the image light ML from the prism mirror 22 and passes it, and makes it enter the see-through mirror 23.

[0026] The see-through mirror 23 is a curved plate-like optical member that functions as a concave surface mirror, and reflects the image light ML incident from the prism mirror 22 through the plate-like optical element 28 toward the pupil position PP. The pupil position PP is a position where the image light ML from each point on the display surface 11d is incident so as to overlap from an angular direction corresponding to the position of each point on the display surface 11d in a predetermined divergent or parallel state. The see-through mirror 23 covers the pupil position PP where the eye EY or pupil is located, has a concave shape toward the pupil position PP, and has a convex shape toward the outside world. The see-through mirror 23 is a mirror plate having a structure in which a mirror film 23c is formed on the front or back surface of the plate-like body 23b. The reflecting surface 23a of the see-through mirror 23 has transparency. The outside light OL that passes through the see-through mirror 23 and the support plate 41 around it is also incident on the pupil position PP. In other words, the wearer US wearing the image display device 200 can observe a virtual image by the image light ML superimposed on an outside world image.

[0027] In the above, the optical surfaces constituting the projection lens 21, the prism mirror 22, the plate-like optical element 28, and the see-through mirror 23 include free-form surfaces, and at least some of the optical surfaces can be replaced with aspherical or spherical surfaces.

[0028] The imaging optical system 20 is an off-axis optical system OS due to the see-through mirror 23 being a concave mirror, etc. In the present embodiment, the projection lens 21, the prism mirror 22, the plate-shaped optical element 28, and the see-through mirror 23 are arranged non-axisymmetrically and have a non-axisymmetric optical surface. In this imaging optical system 20, that is, the off-axis optical system OS, the optical axis AX is bent so that the optical axis AX extends along an off-axis plane (a plane parallel to the YZ plane) corresponding to the paper surface. In this imaging optical system 20, the optical axis AX is bent within the off-axis plane parallel to the YZ plane, so that the optical elements 21, 22, and 23 are arranged along the off-axis plane. The imaging optical system 20 includes optical axis portions AX1, AX2, and AX3 that are arranged along an off-axis plane (a plane parallel to the YZ plane) that is a reference plane extending in the vertical direction and are inclined to each other before and after the reflecting surface. The optical axis AX as a whole extends along the optical path of the chief ray emitted from the center of the display element 11a and passes through the eye ring ER corresponding to the eye point or the center of the pupil. When viewed in a cross section parallel to the YZ plane, the optical axis AX is arranged in a Z-shape with multiple optical axis portions AX1, AX2, and AX3. In other words, on an off-axis plane parallel to the YZ plane, the optical path P1 from the projection lens 21 to the internal reflection surface 22b, the optical path P2 from the internal reflection surface 22b to the see-through mirror 23, and the optical path P3 from the see-through mirror 23 to the pupil position PP are folded back in two stages in a Z-shape.

[0029] As shown in FIG. 9, the display image formed on the display surface 11d of the first display element 11a is a corrected image DA1 that has a distortion such as trapezoidal distortion in advance. In other words, since the imaging optical system 20 is an off-axis optical system OS, it is not easy to completely remove distortion such as trapezoidal distortion by the optical system itself. Therefore, by making the image displayed on the first display element 11a have an inverse distortion that cancels out the distortion formed by the projection lens 21, the prism mirror 22, the plate-shaped optical element 28, and the see-through mirror 23, the pixel arrangement of the projected image IG1 of the virtual image observed at the pupil position PP through the imaging optical system 20 can be a lattice pattern corresponding to the original display image DA0, and the outline can be made rectangular. In other words, the first display element 11a corrects the distortion formed by the projection lens 21, the prism mirror 22, the plate-shaped optical element 28, and the see-through mirror 23. As a result, it is possible to suppress aberration as a whole including the first display element 11a while allowing distortion generated by the see-through mirror 23 and the like. This increases the degree of freedom in the arrangement and size of optical elements such as the prism mirror 22, making it possible to easily ensure the optical performance of the first display unit 100a while achieving a reduction in size of the first display unit 100a.

[0030] Although the first display unit 100a has been described above, the second display unit 100b has a similar structure to the first display unit 100a, and therefore a detailed description of the structure will be omitted.

[0031] The fixing member 78 will be described below with reference to FIG. 10A. In FIG. 10A, an area FR1 is a front view showing the fixing member 78, an area FR2 is a plan view of the fixing member 78, and an area FR3 is a perspective view of the fixing member 78. The fixing member 78 is a dumbbell-shaped member having a pair of spherical first fixing parts 81a and second fixing parts 82a at both ends of a bridge 78a. The bridge (connecting part) 78a is a connecting part that connects the first fixing part 81a and the second fixing part 82a. The bridge 78a has a shape in which both ends of an elongated web 78j extending along the XZ plane are sandwiched between a pair of elongated flanges 78i extending along the XY plane. That is, the bridge 78a is a bar material having an H-shaped cross section (see FIG. 10B). By making the bridge 78a a member having an H cross section, it is possible to reduce the weight of the bridge 78a while ensuring its strength.

[0032] The connecting members 81 and 82 will be described with reference to FIGS. 10A and 10B. The first fixing portion 81a, which is a spherical member formed at one end of the bridge 78a of the fixing member 78, is rotatably fitted into the first recess 81b, which is a semispherical recessed member formed in the first frame 61a. The combination of the first fixing portion 81a and the first recess 81b is called the first connecting member 81. The spherical convex surface of the first fixing portion 81a is called the facing surface 78s, and the spherical concave surface of the first recess 81b is called the facing surface 61s. The curvature of the facing surface 78s of the first fixing portion 81a is set to be larger than the curvature of the facing surface 61s of the first recess 81b. This allows an adhesive material to be injected between the facing surfaces 78s and 61s to form an adhesive layer 88 having a sufficient thickness, thereby increasing the adhesive strength between the first fixing portion 81a and the first recess 81b. The second fixing portion 82a, which is a spherical member formed at the other end of the bridge 78a of the fixing member 78, is rotatably fitted into the second recess 82b, which is a semispherical recess member formed in the second frame 61b. The combination of the second fixing portion 82a and the second recess 82b is called the second connecting member 82. The curvature of the spherical facing surface 78s of the second fixing portion 82a is set to be larger than the curvature of the spherical facing surface 61s of the second recess 82b. This allows an adhesive material to be injected between the facing surface 78s and the facing surface 61s to form an adhesive layer 88 with a sufficient thickness, thereby increasing the adhesive strength between the second fixing portion 82a and the second recess 82b.

[0033] The lower surface 78u of the bridge (connection portion) 78a is disposed at approximately the same position as the reference line SL passing through the symmetrical center of the first fixed portion 81a or above the reference line SL, i.e., on the +Y side. In other words, the bridge 78a is connected to the first fixed portion 81a and the second fixed portion 82a on the upper side away from the first frame 61a and the second frame 61b with respect to the center of the first fixed portion 81a and the center of the second fixed portion 82a. Furthermore, a gap GR is secured between the lower surface 78u of the bridge 78a and the surfaces 61f of the first frame 61a and the second frame 61b. This ensures a change in posture of the first frame 61a and the second frame 61b rotating around the X-axis parallel to the extension direction of the bridge 78a and the Z-axis perpendicular to the X-axis and parallel to the extension direction of the first frame 61a, while deepening the fit between the first fixing portion 81a and the first recess 81b and the fit between the second fixing portion 82a and the second recess 82b, thereby stabilizing the connection between the first frame 61a and the second frame 61b by the fixing member 78. Note that by increasing the size of the first fixing portion 81a and the second fixing portion 82a, the bonding area can be increased, making it easier to stabilize the fixation.

[0034] 11 is a partially cutaway perspective view illustrating a state in which the fixing member 78 is fixed to the first display unit 100a. The first fixing portion 81a is formed with a first hole 81k through which a screw for screwing the first frame 61a to the first fixing portion 81a is passed. A cylindrical boss 81m formed in the center of the first recess 81b of the first frame 61a and extending in the Y direction is inserted from below into the first hole 81k.

[0035] As shown in an enlarged view in FIG. 12A, the first fixing portion 81a of the fixing member 78 is fitted into the first recess 81b formed in the first frame 61a. The combination of the first fixing portion 81a and the first recess 81b is a bearing-like connecting member 81 that allows relative rotation in three axial directions within a small angle range. In other words, the connecting member 81 has three degrees of rotational freedom. The extension portion 71c of the first cover member 71a is arranged so as to cover the connecting member 81. The extension portion 71c is formed with a hemispherical third recess 71j into which the first fixing portion 81a is inserted. The concave surface of the third recess 71j is called the facing surface 71s. The facing surface 71s of the third recess 71j is arranged in the vicinity of and facing the facing surface 78s of the first fixing portion 81a. Here, the curvature of the spherical facing surface 71s of the third recess 71j is set to be substantially equal to the curvature of the spherical facing surface 78s of the first fixing portion 81a, unlike the case of the first recess 81b. A cylindrical boss 71m extending in the Y direction is formed in the center of the third recess 71j, and is inserted into a first hole 81k for screwing formed in the first fixing portion 81a. A screw SB is passed through the hole of the boss 71m, and the tip SBa of the screw SB is screwed into the boss 81m on the first frame 61a side. This allows the first cover member 71a to be fixed to the first frame 61a with the fixing member 78 sandwiched therebetween, and the adhesion of the first fixing portion 81a to the first frame 61a can be reinforced. An adhesive layer can be provided between the facing surface 78s of the first fixing portion 81a and the facing surface 71s of the third recess 71j to strengthen the fixation.

[0036] As shown in an enlarged view in FIG. 12B, the second fixing portion 82a of the fixing member 78 is fitted into the second recess 82b formed in the second frame 61b. The combination of the second fixing portion 82a and the second recess 82b is a bearing-like connecting member 82 that allows relative rotation in three axial directions within a small angle range. In other words, the connecting member 82 has three degrees of rotational freedom. The extension portion 71c of the second cover member 71b is arranged to cover the connecting member 82. The extension portion 71c is formed with a hemispherical fourth recess 71k into which the second fixing portion 82a is inserted. The concave surface of the fourth recess 71k is called the facing surface 71s. The facing surface 71s of the fourth recess 71k is arranged in the vicinity of and facing the facing surface 78s of the second fixing portion 82a. Here, the curvature of the spherical facing surface 71s of the fourth recess 71k is set to be substantially equal to the curvature of the spherical facing surface 78s of the second fixing portion 82a, unlike the case of the second recess 82b. A cylindrical boss 71m extending in the Y direction is formed in the center of the fourth recess 71k, and is inserted into a second hole 82k for screwing formed in the second fixing portion 82a. A screw SB is passed through the hole of the boss 71m, and the tip SBa of the screw SB is screwed into the boss 82m on the second frame 61b side. This allows the second cover member 71b to be fixed to the second frame 61b with the fixing member 78 sandwiched therebetween, and the adhesion of the second fixing portion 82a to the second frame 61b can be reinforced. An adhesive layer can be provided between the facing surface 78s of the second fixing portion 82a and the facing surface 71s of the fourth recess 71k to strengthen the fixation.

[0037] The manufacturing, i.e., assembly, of the image display device 200 will be described below. First, the first optical system 12a and the first combiner 103a are fixed to the first frame 61a, and the display element 11a is fixed while being positioned relative to the first optical system 12a using the first holder 72a or the like. This results in a right eye unit RU including the first display section 100a (see FIG. 4). In parallel with this, the second optical system 12b and the second combiner 103b are fixed to the second frame 61b, and the display element 11b is fixed while being positioned relative to the second optical system 12b using the second holder 72b or the like. This results in a left eye unit LU including the second display section 100b (see FIG. 4). After that, the right eye unit RU and the left eye unit LU are set in a dual-system measuring device, and the elastic sheet 75 is fixed onto the first frame 61a and the second frame 61b by adhesion. At this time, the openings OP21, OP22 on the inside of the elastic sheet 75 are sealed by the first frame 61a and the second frame 61b. Furthermore, the fixing member 78 is moved downward to fit the first fixing portion 81a of the fixing member 78 into the first recess 81b of the first frame 61a, and the second fixing portion 82a of the fixing member 78 into the second recess 82b of the second frame 61b. Thereafter, the mutual angles and positions of the right eye unit RU and the left eye unit LU are precisely adjusted using the stage of the dual-system measurement device. At this time, the right eye unit RU and the left eye unit LU can be independently rotated in the R1 direction around the X axis, the R2 direction around the Y axis, and the R3 direction around the Z axis while connected by the fixing member 78 (see FIG. 4, etc.). After the position adjustment is completed, the adhesive previously supplied between the first fixing portion 81a and the first recess 81b is hardened, and the adhesive previously supplied between the second fixing portion 82a and the second recess 82b is hardened. This completes the alignment of the right eye unit RU and the left eye unit LU. Thereafter, the first cover member 71a is placed over the first frame 61a so as to cover the first optical system 12a, the inner periphery 75b of the elastic sheet 75 is sandwiched between the first frame 61a and the first cover member 71a, and the boss 71m provided in the third recess 71j of the first cover member 71a is inserted into the first hole 81k of the first fixing portion 81a (see FIG. 12A).Then, the screw SB is passed through the hole of the boss 71m and screwed into the boss 81m on the opposing first frame 61a side in the first hole 81k of the first fixing portion 81a. This completes the fixing of the first cover member 71a to the first frame 61a. The method of fixing the second cover member 71b to the second frame 61b is the same as the method of fixing the first cover member 71a to the first frame 61a, and the explanation will be omitted. Next, the circuit board 91 is attached to the fixing member 78 using the board support portion 74, and the FPC extending from the display elements 11a and 11b is connected to the circuit board 91. Finally, the lower exterior member 107b is fixed to the fixing member 78 using a pair of fastening portions 78z provided on the fixing member 78, and the upper exterior member 107a is fixed to the lower exterior member 107b. At this time, the first frame 61a and the second frame 61b are allowed to be slightly displaced with respect to the lower exterior member 107b, and the positioning of the first display unit 100a and the first display unit 100b is maintained with respect to the fixing member 78. Furthermore, by sandwiching the outer periphery 75a of the elastic sheet 75 between the outer edge 7a of the upper exterior member 107a and the outer edge 7b of the lower exterior member 107b, a seal is achieved between them, and the internal space of the exterior member 107 is sealed.

[0038] The image display device 200 of the above embodiment includes a first display unit 100a having a first frame 61a and a first optical system 12a, a second display unit 100b having a second frame 61b and a second optical system 12b, and a fixing member 78 that fixes the first display unit 100a and the second display unit 100b relatively, and the fixing member 78 has a shape that allows the first optical system 12a and the second optical system 12b to rotate in two or more rotational directions when aligning the first display unit 100a and the second display unit 100b before fixing them. This allows the first display unit 100a and the second display unit 100b to be positioned and aligned with respect to the fixing member 78 with a high degree of freedom before fixing.

[0039] The manufacturing method of the image display device 200 of the above embodiment includes a first display unit 100a having a first frame 61a and a first optical system 12a, a second display unit 100b having a second frame and a second optical system 12b, and a fixing member 78 that fixes the first display unit 100a and the second display unit 100b relatively, the fixing member 78 having a shape that allows the first optical system 12a and the second optical system 12b to rotate in two or more rotational directions, and after alignment, the rotation of the first optical system 12a and the second optical system 12b relative to the fixing member 78 is stopped. In this case, before fixing, the first display unit 100a and the second display unit 100b can be arranged and aligned with a high degree of freedom relative to the fixing member 78. Furthermore, after alignment, the rotation of the first optical system 12a and the second optical system 12b relative to the fixed member 78 is stopped, so that the relative positional relationship of the first display unit 100a and the second display unit 100b with respect to the fixed member 78 can be stably maintained.

[0040] [Variations 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.

[0041] The imaging optical system 20 incorporated in the first display unit 100a is not limited to the one shown in the figure, and may have various configurations. Specifically, the imaging optical system 20 is an off-axis optical system OS having asymmetry in the Y direction or vertical direction, but it may also be an off-axis optical system having asymmetry in the X direction or horizontal direction. The optical elements constituting the imaging optical system 20 shown in FIG. 8 are also merely exemplary, and modifications such as increasing or decreasing the number of lenses, adding mirrors, or adding light-guiding members are possible.

[0042] A dimming device that adjusts light by limiting the light transmitted through the combiners 103a and 103b can be attached to the outside world side of the combiners 103a and 103b. The dimming device adjusts the transmittance electrically, for example. 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.

[0043] The combiners 103a and 103b can be replaced with light-shielding mirrors, in which case the optical system becomes a non-see-through type that does not assume direct observation of the outside world image.

[0044] The first frame 61a, the second frame 61b, and the fixing member 78 are not limited to those made of a metal material, and may be made of fiber reinforced plastic (FRP).

[0045] The structure of the connecting members 81, 82 is not limited to a ball joint type, but can be replaced with various mechanisms that increase the degree of rotational freedom to two or more axes.

[0046] In the above description, it is assumed that the image display device 100 is used by being mounted on the head, but the image display device 100 can also be used as a handheld display that is not mounted on the head and is peered at like binoculars. In other words, in the present invention, the head mounted display also includes a handheld display.

[0047] In a specific embodiment, the image display device comprises a first display unit having a first frame and a first optical system, a second display unit having a second frame and a second optical system, and a fixing member that fixes the first display unit and the second display unit relative to each other, and the fixing member has a shape that allows the first optical system and the second optical system to be rotatable in two or more rotational directions when aligning the first display unit and the second display unit before fixing them.

[0048] In the image display device, since the fixing member has a shape that allows the first optical system and the second optical system to rotate in two or more rotational directions, the first display unit and the second display unit can be arranged and aligned with a high degree of freedom relative to the fixing member before being fixed. After the alignment, the first display unit and the second display unit can be fixed to the fixing member using an adhesive or a fastener, thereby stably maintaining their relative positional relationship.

[0049] In a specific aspect, a bearing-like connecting member having three degrees of rotational freedom is provided between the fixed member and the first display unit, and between the fixed member and the second display unit, respectively. In this case, the first display unit and the second display unit can be freely positioned with respect to the fixed member.

[0050] In a specific aspect, the connecting member is stopped from rotating after the alignment, thereby ensuring that the position is maintained after the alignment while ensuring free adjustment of the position before the alignment.

[0051] In a specific aspect, the fixing member has a spherical first fixing portion provided on the first frame side and a spherical second fixing portion provided on the second frame side, the first frame has a hemispherical first recess into which the first fixing portion is inserted, the second frame has a hemispherical second recess into which the second fixing portion is inserted, and the first fixing portion and first recess, which are connecting members, and the second fixing portion and second recess, which are connecting members, are joined in an aligned state with an adhesive layer formed therebetween. In this case, the first frame and the second frame can be freely rotated with respect to the fixing member by a simple fitting structure to adjust the attitude.

[0052] In a specific aspect, the first display unit has a first cover member covering the first fixed portion and the first optical system from the opposite side of the first frame, the first cover member having a hemispherical third recess into which the first fixed portion is inserted, the second display unit has a second cover member covering the second fixed portion and the second optical system from the opposite side of the second frame, the second cover member having a hemispherical fourth recess into which the second fixed portion is inserted, and the first fixed portion and the third recess, and the second fixed portion and the fourth recess are fixed by screws. In this case, the first cover member and the second cover member can be attached to the first frame and the second frame via the first fixed portion and the second fixed portion.

[0053] In a specific aspect, the first fixing portion and the first recess have spherical opposing surfaces with different curvatures, and the second fixing portion and the second recess have spherical opposing surfaces with different curvatures, which makes it easy to inject an adhesive material to form an adhesive layer with a sufficient thickness.

[0054] In a specific aspect, the first fixing portion and the third recess have opposing spherical surfaces with the same curvature, and the second fixing portion and the fourth recess have opposing spherical surfaces with the same curvature.

[0055] In a specific aspect, the first fixing portion has a first hole through which a screw for screwing the first frame to the first fixing portion is passed, and the second fixing portion has a second hole through which a screw for screwing the second frame to the second fixing portion is passed. In this case, the first frame can be reliably fixed to the first fixing portion, and fixing strength can be ensured.

[0056] In a specific aspect, the fixing member has a connection part that connects the first fixing part and the second fixing part, and the connection part is connected to the first fixing part and the second fixing part on the side away from the first frame and the second frame with reference to the center of the first fixing part and the center of the second fixing part. This makes it possible to stabilize the connection by deepening the fit between the first fixing part and the first recess and the fit between the second fixing part and the second recess while ensuring a change in posture when the first frame and the second frame rotate around an axis perpendicular to the extension direction of the connection part.

[0057] In a specific aspect, the fixing member has a board support portion that supports the circuit board. In this case, the circuit board can be supported relative to the first frame and the second frame, and various members can be collectively supported with the fixing member as a base.

[0058] A specific embodiment of a manufacturing method for an image display device is a manufacturing method for an image display device including a first display unit having a first frame and a first optical system, a second display unit having a second frame and a second optical system, and a fixing member that fixes the first display unit and the second display unit relative to each other, wherein the fixing member has a shape that allows the first optical system and the second optical system to be rotatable in rotational directions about two or more axes, and after alignment, the rotation of the first optical system and the second optical system relative to the fixing member is stopped.

[0059] In the above manufacturing method, since the fixed member has a shape that allows the first optical system and the second optical system to rotate in two or more rotational directions, the first display unit and the second display unit can be arranged and aligned with a high degree of freedom relative to the fixed member before being fixed. Furthermore, since the rotation of the first optical system and the second optical system relative to the fixed member is stopped after the alignment, the relative positional relationship of the first display unit and the second display unit with respect to the fixed member can be stably maintained. [Explanation of symbols]

[0060] Reference Signs List 11a, 11b...display element, 12a...first optical system, 12b...second optical system, 20...imaging optical system, 21...projection lens, 22...prism mirror, 23...see-through mirror, 28...plate-shaped optical element, 61a...first frame, 61b...second frame, 61s...opposing surface, 71a...first cover member, 71b...second cover member, 71j...third recess, 71k...fourth recess, 71s...opposing surface, 75...elastic sheet, 78...fixing member, 78a...bridge, 78s...opposing surface, 81, 82...connecting member, 81a...first fixing portion, 81b...second 1 recess, 81k...first hole, 82a...second fixing portion, 82b...second recess, 82k...second hole, 88...adhesive layer, 91...circuit board, 100...image display device, 100a...first display portion, 100b...second display portion, 102...display drive portion, 103a...first combiner, 103b...second combiner, 200...image display device, 200a...main body, 200b...support device, AX...optical axis, ER...eye ring, EY...eye, ML...image light, OL...external light, OP1...opening, OP21, OP22...opening, OS...off-axis optical system, US...wearer

Claims

1. a first display unit having a first frame and a first optical system; a second display unit having a second frame and a second optical system; a fixing member that fixes the first display unit and the second display unit relatively to each other, the fixing member is a dumbbell-shaped member having a pair of spherical first and second fixing portions at both ends of a connection portion, and fixes the first display portion and the second display portion; An image display device, wherein a bearing-shaped connecting member having three degrees of rotational freedom is provided between the fixed member and the first display unit, and between the fixed member and the second display unit.

2. the fixing member has the first fixing portion having a spherical shape provided on the first frame side and the second fixing portion having a spherical shape provided on the second frame side, the first frame has a hemispherical first recess into which the first fixing portion is inserted, the second frame has a hemispherical second recess into which the second fixing portion is inserted, The image display device according to claim 1 , wherein an adhesive layer is formed between the first fixing portion and the first recess which are the connecting member, and the second fixing portion and the second recess which are the connecting member.

3. the first display unit has a first cover member that covers the first fixed unit and the first optical system from an opposite side of the first frame, the first cover member having a hemispherical third recess into which the first fixed unit is inserted, the second display unit has a second cover member that covers the second fixed unit and the second optical system from an opposite side of the second frame, the second cover member having a fourth semi-spherical recess into which the second fixed unit is inserted; The image display device according to claim 2 , wherein the first fixing portion and the third recess, and the second fixing portion and the fourth recess are fixed by screws.

4. 3. The image display device according to claim 2, wherein the first fixing portion and the first recess have opposing spherical surfaces with different curvatures, and the second fixing portion and the second recess have opposing spherical surfaces with different curvatures.

5. An image display device as described in claim 3, wherein the first fixed portion and the first recess have opposing spherical surfaces with different curvatures, and the second fixed portion and the second recess have opposing spherical surfaces with different curvatures.

6. 6. The image display device according to claim 5, wherein the first fixing portion and the third recess have opposing spherical surfaces with the same curvature, and the second fixing portion and the fourth recess have opposing spherical surfaces with the same curvature.

7. The image display device according to any one of claims 3 to 6, wherein the first fixing portion has a first hole through which a screw for screwing the first frame to the first fixing portion is passed, and the second fixing portion has a second hole through which a screw for screwing the second frame to the second fixing portion is passed.

8. An image display device as described in any one of claims 3 to 7, wherein the connection portion is connected to the first fixed portion and the second fixed portion on the side away from the first frame and the second frame based on the center of the first fixed portion and the center of the second fixed portion.

9. 1. A method for manufacturing an image display device including a first display unit having a first frame and a first optical system, a second display unit having a second frame and a second optical system, and a fixing member that fixes the first display unit and the second display unit relatively to each other, comprising: the fixing member is a dumbbell-shaped member having a pair of spherical first and second fixing portions at both ends of a connection portion, and has a shape that allows the first optical system and the second optical system to rotate in two or more rotational directions; After the alignment, the first optical system and the second optical system are bonded to the fixing member. A method for manufacturing an image display device.

Images