Virtual image display device

Abstract

To prevent, when a display unit or a frame member is fixed onto a coupling member by means of a photo-curing type adhesive agent, the adhesive agent from remaining in a semi-cured or uncured state.SOLUTION: A virtual image display device DD comprises: a first display unit 100a that has a first video element 11a, a first projection optical system 12a, and a first mirror M1; a second display unit 100b that has a second video element 11b, a second projection optical system 12b, and a second mirror M2; a coupling member 50c that couples the first display unit 100a with the second display unit 100b; a penetration type fitting structure 51 that is formed on a joint part 50p formed on the first display unit 100a and a support part 50q provided on the coupling member 50c; and a photo-curing type adhesion member BA held between the joint part 50p and the support part 50q. In any one of the joint part 50p and the support part 50q, additive light-transmissive structures TR1 that cause light to reach a boundary region G2 between the joint part 50p and the support part 50q are formed in a vicinity of the fitting structure 51.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a head-mounted virtual image display device that enables viewing of a virtual image. [Background technology]

[0002] A known virtual image display device has a structure that includes two image display devices lined up horizontally, a connecting member that connects two light guiding means provided on these image display devices at the top of their central ends, and a glasses-type frame that is worn on the observer's head, with the connecting member attached to the center of the frame and supported in a suspended manner (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-18414 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the device of the background art described above, the method of fixing the coupling member and the light guiding means is described as using screws or adhesive, but in consideration of manufacturing variations, etc., fixing with adhesive rather than with screws allows for greater freedom of adjustment. Among adhesives, a photocurable adhesive is preferable from the viewpoint of shortening the process, etc.

[0005] However, when the connecting member and the light-guiding means are fixed with a light-curing adhesive, if the connecting member is made of metal, for example, and a shadow is formed in the curing light, the adhesive will remain in a semi-cured or uncured state, making it difficult to ensure the bonding strength. [Means for solving the problem]

[0006] A virtual image display device according to one aspect of the present invention comprises a first display unit having a first image element, a first projection optical system that projects image light from the first image element, and a first mirror that reflects the image light from the first projection optical system, a connecting member that connects the first display unit and a second display unit, a through-type fitting structure formed between a joint formed on the first display unit and a support provided on the connecting member, and a light-curing adhesive member that is filled between the joint and the support, and a light-transmitting structure is formed in either the joint or the support near the fitting structure and between the joint and the support. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is an external perspective view illustrating a state in which the head-mounted display device is worn. [Diagram 2] FIG. 2 is a side cross-sectional view illustrating an optical system and the like included in one of the virtual image display devices. [Diagram 3] FIG. 2 is a perspective view illustrating a display unit and its supporting structure. [Figure 4] 3A and 3B are a plan view and a cross-sectional view from the front of the support device. [Diagram 5] 4 is an enlarged cross-sectional view showing a joint portion of a first frame member and a support portion of a connecting member. FIG. [Figure 6] FIG. 13 is a plan view illustrating a supporting device according to a modified example. [Figure 7] FIG. 13 is a plan view illustrating a supporting device according to another modified example. [Figure 8] FIG. 11 is a partially enlarged cross-sectional view illustrating yet another modified example. [Figure 9] FIG. 2 is a perspective view illustrating the outer shape of a display unit. [Figure 10] FIG. 2 is a side cross-sectional view of a barrel and an optical member held therein. [Figure 11] FIG. 11 is a partially enlarged cross-sectional view illustrating a support device according to a second embodiment. [Figure 12] FIG. 13 is a plan view illustrating a support device according to a third embodiment. [Figure 13] FIG. 13 is a front view illustrating a supporting device according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] [First embodiment] Hereinafter, a first embodiment of a virtual 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 a head-mounted display device (hereinafter also referred to as a head-mounted display or HMD) 200, which is a virtual image display device DD of the first embodiment. The virtual image display device DD, i.e., the HMD 200, allows an observer or wearer US wearing it 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 both eyes EY of the observer or wearer US wearing the HMD 200 are aligned, the +Y direction corresponds to the upward direction perpendicular to the lateral direction in which both 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 virtual image display device DD includes a first virtual image display 100A for the right eye, a second virtual image display 100B for the left eye, a pair of temple-shaped wearing devices 100C supporting the virtual image displays 100A and 100B, and a user terminal 90 which is an information terminal. The first virtual image display 100A functions as an HMD by itself and is composed of a first display drive unit 102a arranged at the top and a first combiner 103a in the shape of a glasses lens and covering the front of the eyes. Similarly, the second virtual image display 100B functions as an HMD by itself and is composed of a second display drive unit 102b arranged at the top and a second combiner 103b in the shape of a glasses lens and covering the front of the eyes. The wearing device 100C is worn on the head of the wearer US and supports the upper end sides of the pair of combiners 103a and 103b via the display drive units 102a and 102b which are integrated in appearance. The first virtual image display device 100A and the second virtual image display device 100B are optically identical or are left-right inverted, and a detailed description of the second virtual image display device 100B will be omitted.

[0011] FIG. 2 is a side cross-sectional view illustrating the internal structure of the first virtual image display device 100A. The first virtual image display device 100A includes a first image element 11a, a first display unit 20a, and a first circuit member 80a. The first display unit 20a is an imaging optical system that forms a virtual image, and includes a projection lens 21, a prism mirror 22, and a see-through mirror 23. In the first display unit 20a, the projection lens 21 and the prism mirror 22 function as a first projection optical system 12a into which the image light ML from the first image element 11a is incident. The first display unit 20a includes the first projection optical system 12a and the see-through mirror 23 in an integrated state. The projection lens 21 constituting the first projection optical system 12a corresponds to the first optical member 2a arranged on the light exit side of the first image element 11a, and the prism mirror 22 corresponds to the second optical member 2b arranged on the light exit side of the first optical member 2a, which is the projection lens 21. Moreover, the first image element 11a, the projection lens 21, and the prism mirror 22 correspond to a part of the first display drive unit 102a shown in Fig. 1, and the see-through mirror 23 corresponds to the first combiner 103a shown in Fig. 1. The projection lens 21 and the prism mirror 22 constituting the first projection optical system 12a are fixed together with the first image element 11a in a state where they are positioned relative to each other within a container-shaped barrel 41. The barrel 41 is a case CA that houses the first projection optical system 12a and the first image element 11a in a positioned state.

[0012] In the first virtual image display 100A, the first image element 11a is a self-luminous image light generating device. The first image element 11a emits image light ML to the first projection optical system 12a. The first image element 11a is stored and supported in the barrel 41 from the rear. The first image element 11a is, for example, an organic EL (organic electroluminescence) display, and forms a color still image or moving image on a two-dimensional display surface 11d. The first image element 11a is driven by a display control device 88 including a first circuit member 80a to perform a display operation. The first image element 11a is not limited to an organic EL display, and can be replaced with a display device using an inorganic EL, an organic LED, an LED array, a laser array, a quantum dot light-emitting element, or the like. The first image 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 image element 11a, instead of an LCD, LCOS (Liquid crystal on silicon, LCoS is a registered trademark), a digital micromirror device, or the like may be used. In the first virtual image display 100A, an optical device excluding the first circuit member 80a and the display control device 88 is called an optical unit 100.

[0013] The first display unit 20a includes two reflecting surfaces, and the optical path is bent by the see-through mirror 23 and the prism mirror 22. The first display unit 20a is an off-axis optical system OS. That is, the projection lens 21, the prism mirror 22, and the see-through mirror 23 are arranged non-axisymmetrically. In response to this non-axisymmetricality, the optical surfaces of the optical elements constituting the first display unit 20a are, in principle, asymmetric about the optical axis AX in the vertical direction parallel to the YZ plane and intersecting the optical axis AX, and are symmetric about the optical axis AX in the horizontal direction or the X direction. In this first display unit 20a, the optical axis AX is bent in an off-axis plane parallel to the YZ plane, which is a reference plane, so that the optical elements 21, 22, and 23 are arranged along the off-axis plane (i.e., the reference plane). Specifically, on an off-axis plane that is parallel to the YZ plane and corresponds to the paper surface, optical path portion P1 from the projection lens 21 to the reflecting surface 22b, optical path portion P2 from the reflecting surface 22b to the see-through mirror 23, and optical path portion P3 from the see-through mirror 23 to the pupil position PP are arranged to be folded back in two stages in a Z shape.

[0014] In the first display unit 20a, the optical path portion P1 from the projection lens 21 to the reflecting surface 22b extends in a slightly upward diagonal direction toward the rear with respect to the viewpoint as a reference, or in a direction nearly parallel to the Z direction. The optical path portion P2 from the reflecting surface 22b to the see-through mirror 23 extends in a downward diagonal direction toward the front. When the horizontal plane direction (XZ plane) is used as a reference, the inclination of the optical path portion P2 is greater than the inclination of the optical path portion P1. The optical path portion P3 from the see-through mirror 23 to the pupil position PP extends in a slightly upward diagonal direction toward the rear, in the -Z direction, or in a direction nearly parallel to the Z direction. In the illustrated example, the portion of the optical axis AX corresponding to the optical path portion P3 is at about -10° toward the +Z direction, with the downward direction being negative.

[0015] In the first display unit 20a, the projection lens 21 includes a first lens 21o, a second lens 21p, and a third lens 21q. The projection lens 21 receives the image light ML emitted from the first image element 11a and causes it to enter a prism mirror 22. The projection lens 21 focuses the image light ML emitted from the first image element 11a into a state close to a parallel light beam.

[0016] The prism mirror 22 is an optical member having a refractive and reflective function, which has a function combining a mirror and a lens, and reflects the image light ML from the projection lens 21 while refracting it. The prism mirror 22 has an entrance surface 22a arranged on the light exit side of the first optical member 2a, a reflecting surface 22b which bends the optical axis AX, and an exit surface 22c which faces the reflecting surface 22b and is arranged in a direction symmetrical to the entrance surface 22a. The prism mirror 22 emits the image light ML incident from the front where the projection lens 21 is arranged, so as to bend it back in a direction inclined downward with respect to a direction in which the incident direction is reversed (the direction of the light source as seen from the prism mirror 22). The reflecting surface 22b is not limited to one which reflects the image light ML by total reflection, but may be a reflecting surface made of a metal film or a dielectric multilayer film.

[0017] The see-through mirror 23, i.e., the first combiner 103a, is a curved plate-like optical appearance component 123 that functions as a concave surface mirror, and partially reflects the image light ML from the prism mirror 22 and partially transmits the outside light OL. The see-through mirror 23 has a partially reflecting surface 23c and an outer surface 23o. The see-through mirror 23 covers the pupil position PP where the eye EY or pupil is located and has a concave shape toward the pupil position PP, and as a result, has a convex shape toward the outside world. The pupil position PP or its opening PPa is called the eye point or eye box, and corresponds to the exit pupil EP of the first display unit 20a including the see-through mirror 23. As a concave mirror with positive power, the see-through mirror 23 enables the intermediate image IM formed on the first image element 11a and re-imaged by the first projection optical system 12a to be viewed in an enlarged manner.

[0018] The partially reflecting surface 23c of the see-through mirror 23 transmits a part of the light when reflecting the image light ML. As a result, the outside light OL passes through the see-through mirror 23, making it possible to see through the outside world, and a virtual image can be superimposed on the outside world image. In this case, if the base material 23b is thin, about a few mm or less, the change in magnification of the outside world image can be kept small. The reflectance of the partially reflecting surface 23c to the image light ML and the outside light OL is set to 10% or more and 50% or less in the assumed range of incidence angles of the image light ML, from the viewpoint of ensuring the brightness of the image light ML and facilitating the observation of the outside world image by see-through. The base material 23b of the see-through mirror 23 is formed of, for example, a resin, but can also be made of glass. The base material 23b is formed of the same material as the support plate 61 that supports it from the periphery, and has the same thickness as the support plate 61. The transmissive reflecting film 23a is formed of, for example, a dielectric multilayer film consisting of a plurality of dielectric layers with adjusted film thicknesses. The transmissive reflective film 23a may be a single-layer film or a multi-layer film of a metal such as Al or Ag, the thickness of which is adjusted.

[0019] Regarding the optical path, the image light ML from the first image element 11a enters the projection lens 21 and is emitted from the projection lens 21 in a substantially collimated state. The image light ML that passes through the projection lens 21 enters the prism mirror 22 and passes through while being refracted at the entrance surface 22a, is reflected by the reflecting surface 22b with a high reflectance close to 100%, and is refracted again at the exit surface 22c. The image light ML from the prism mirror 22 forms an intermediate image IM once, then enters the see-through mirror 23 and is reflected by the partially reflecting surface 23c with a reflectance of about 50% or less. The image light ML reflected by the see-through mirror 23 enters the pupil position PP where the eye EY or pupil of the wearer US is located. External light OL that passes through the see-through mirror 23 and the support plate 61 around it also enters the pupil position PP. That is, the wearer US wearing the first virtual image display device 100A can observe a virtual image generated by the image light ML superimposed on an external image.

[0020] A support structure incorporated in the display driving units 102a and 102b of the virtual image display device DD will be described with reference to Figures 3 and 4. Figure 3 is a perspective view illustrating the support structure of the display unit. Figure 4 is a diagram illustrating the support device 50 in detail. In Figure 4, area AR1 is a plan view of the support device 50, and area AR2 is a cross-sectional view of the support device 50 shown in area AR1, taken along the line AA.

[0021] In the first virtual image display 100A, the first frame member 52a constituting the support device 50 is fixed to the upper portion 41x of the first display unit 20a using fastening members 50f such as screws, and supports the first display unit 20a or the barrel 41 so as to suspend it. The first frame member 52a can be fixed by various methods such as fixing by caulking, fixing by adhesive, fixing by fitting, and fixing by adhesive, in addition to fixing by screws. The first frame member 52a is a part of the first display unit 100a corresponding to the first virtual image display 100A. Here, as shown in FIG. 2, the first display unit 100a has a first image element 11a, a first projection optical system 12a that projects an image formed on the first image element 11a, and a first combiner 103a that is a first mirror M1 that reflects the image light ML emitted from the first projection optical system 12a.

[0022] Referring mainly to FIG. 4, the first frame member 52a includes a flat plate portion 55a having an opening 52o and a generally rectangular shape as a whole, and a pair of reinforcing projections 55b, 55c projecting upward from the flat plate portion 55a. The first reinforcing projection 55b projects on the upper side, which is the +Y side, and on the lower side, which is the -Y side, and extends in the horizontal X direction as a whole while being slightly curved. The second reinforcing projection 55c projects only on the upper side, which is the +Y side, and extends in the horizontal X direction as a whole while being slightly curved. The pair of reinforcing projections 55b, 55c increase the structural strength of the first frame member 52a, and increase the strength of the flat plate portion 55a, which is relatively weak against bending and twisting.

[0023] In the first frame member 52a, the space above the flat plate portion 55a and sandwiched between the pair of reinforcing protrusions 55b, 55c is a recess RE, in which the first circuit member 80a can be stored. The height of the upper end of the first circuit member 80a may be higher than the height of the upper ends of the pair of reinforcing protrusions 55b, 55c. In the first frame member 52a, screw holes 56c formed at three locations around the opening 52o are used to fix the first circuit member 80a to the first frame member 52a.

[0024] A part of the periphery 52r of the rectangular opening 52o formed in the first frame member 52a (specifically, three sides excluding the +Z side) abuts and adheres closely to the upper part 41x of the barrel 41 of the first display unit 20a shown in FIG. 3. At this time, the lower surface of the first frame member 52a fits into the upper part 41x of the barrel 41, and the first frame member 52a and the first display unit 20a, i.e., the barrel 41, are positioned. The first frame member 52a is formed of a metal material such as a magnesium alloy. By forming the first frame member 52a from a magnesium alloy, it is possible to enhance the effect of cooling the first frame member 52a, the first display unit 20a, etc. by dissipating heat.

[0025] Returning to FIG. 3, in the second virtual image display device 100B, the second frame member 52b constituting the support device 50 is fixed to the upper portion 41y of the barrel 41 of the second display unit 20b using fastening members 50f such as screws, and supports the second display unit 20b or the barrel 41 in a suspended manner. The second frame member 52b is a part of the second display unit 100b corresponding to the second virtual image display device 100B. Here, the second display unit 100b has a second image element 11b, a second projection optical system 12b that projects an image formed on the second image element 11b, and a second combiner 103b that is a second mirror M2 that reflects the image light ML emitted from the second projection optical system 12b (see FIG. 2).

[0026] Referring mainly to Fig. 4, the second frame member 52b also includes a generally rectangular flat plate portion 55a and a pair of reinforcing protrusions 55b, 55c protruding upward from the flat plate portion 55a. The first reinforcing protrusion 55b protrudes upward and downward and extends generally in the horizontal X direction while being slightly curved. The second reinforcing protrusion 55c protrudes only upward and extends generally in the horizontal X direction while being slightly curved.

[0027] In the second frame member 52b, the space above the flat plate portion 55a and sandwiched between the pair of reinforcing protrusions 55b, 55c is a recess RE, in which the second circuit member 80b can be stored. In the second frame member 52b, screw holes 56c formed in three locations around the opening 52o are used to fix the second circuit member 80b to the second frame member 52b.

[0028] A part of the periphery 52r of the rectangular opening 52o formed in the second frame member 52b (specifically, three sides excluding the +Z side) abuts and adheres closely to the upper part 41y of the barrel 41 of the second display unit 20b shown in Fig. 3. At this time, the lower surface of the second frame member 52b fits into the upper part 41y of the barrel 41, and the second frame member 52b and the second display unit 20b, i.e., the barrel 41, are positioned. By forming the second frame member 52b from a metal material such as a magnesium alloy, the effect of cooling the second frame member 52b and the second display unit 20b by heat dissipation can be improved.

[0029] Although not shown, the left end or -X end of the first frame member 52a and the right end or +X end of the second frame member 52b are connected to the mounting device 100C shown in FIG. 1 by connecting members such as hinges, and are supported by the mounting device 100C.

[0030] The support device 50 includes a first frame member 52a and a second frame member 52b, as well as a connecting member 50c that connects the first frame member 52a and the second frame member 52b to fix them relative to each other. The connecting member 50c includes a rectangular flat plate portion 57a ​​and a pair of reinforcing projections 57b that protrude downward from the flat plate portion 57a. The connecting member 50c is a member made of a metal such as a magnesium alloy, and is connected to a joint portion 50p that is one end of the first frame member 52a at a support portion 50q at one end, and is connected to a joint portion 50p that is one end of the second frame member 52b at a support portion 50q at the other end. The first frame member 52a to which the first display unit 20a is attached and the second frame member 52b to which the second display unit 20b is attached are fixed in a state in which they are optically positioned relative to each other via the central connecting member 50c. In this manner, by connecting both frame members 52a, 52b via the connecting member 50c, it becomes easy to adjust the relative positions of both frame members 52a, 52b.

[0031] If the support device 50 is made of metal, and the first frame member 52a, the second frame member 52b, and the connecting member 50c are also made of metal, the strength of each of the parts 52a, 52b, and 50c can be increased, and the structural precision can be improved while keeping the weight low. However, if the connecting member 50c and the frame members 52a and 52b are made of metal, they cannot be made light-transmitting, so an additional light-transmitting structure TR1 is provided as described below to ensure that the light-curing adhesive can be sufficiently cured.

[0032] A through-type fitting structure 51 is formed as a part of a joint 50p formed on the first frame member 52a of the first display unit 100a and a support 50q provided on the joining member 50c. The combination of the joint 50p and the support 50q is called a connecting part JS.

[0033] As shown in FIG. 5, the fitting structure 51 has a pin-shaped protrusion 51a and a through hole 51b having a cylindrical inner surface that fits with the protrusion 51a. The protrusion 51a is formed in the joint portion 50p, and the through hole 51b is formed in the support portion 50q. By combining the protrusion 51a and the through hole 51b, it is possible to easily attach the first display unit 100a (see FIG. 3) to the joining member 50c, and it is possible to easily adjust the relative positions of the first display unit 100a and the second display unit 100b. A cylindrical gap G0, which is an adjustment play formed between the protrusion 51a and the through hole 51b, functions as a light transmission structure TR0.

[0034] In the support portion 50q of the joining member 50c, two slit-shaped holes 50s are formed near the fitting structure 51. The two holes 50s are provided so as to sandwich the fitting structure 51, and extend in the front-rear Z direction so as to cross the joining member 50c. The holes 50s are formed as elongated holes that are shorter than the width of the support portion 50q in the front-rear Z direction and penetrate the support portion 50q. These elongated holes 50s expose a wide area of ​​the boundary region G2 between the joint portion 50p and the support portion 50q, and function as an additional light-transmitting structure TR1 that allows the curing light to reach the boundary region G2. The slit-shaped holes 50s are relatively easy to process, and make it easy to maintain the strength of the support portion 50q. The light-transmitting structure TR1 is provided so as to expose the joint portion 50p, which is the other of the joint portion 50p and the support portion 50q, by penetrating the support portion 50q, which is one of the joint portion 50p and the support portion 50q. The slit-shaped hole 50s exposes the inner area IA of the boundary area G2 between the joint portion 50p and the support portion 50q. By exposing the inner area IA by the slit-shaped hole 50s in this manner, it becomes easy for the curing light to reach the inner area IA and its surroundings, and the boundary area G2 can be cured efficiently over a relatively wide area. In addition, by providing a plurality of slit-shaped holes 50s, it becomes easy for the curing light to reach a plurality of places in the boundary area G2 between the joint portion 50p and the support portion 50q, and the boundary area G2 can be cured over a relatively wide area. In particular, when a plurality of slit-shaped holes 50s are provided so as to sandwich the fitting structure 51, symmetrical and well-balanced fixation can be achieved around the fitting structure 51.

[0035] In the fitting structure 51, the outer diameter of the protrusion 51a is smaller than the inner diameter of the through hole 51b, and the gap G0 between them is filled and cured with the first portion BA1 of the light-curing adhesive member BA. In addition, the two holes 50s provided to sandwich the fitting structure 51, that is, the gap formed in the additional light-transmitting structure TR1, are filled and cured with the second portion BA2 of the light-curing adhesive member BA. Furthermore, the boundary region G2 formed between the upper surface of the joint portion 50p and the upper surface of the support portion 50q is filled and cured with the third portion BA3 of the light-curing adhesive member BA. The joint between the joint portion 50p and the support portion 50q, that is, the joint between the first frame member 52a and the coupling member 50c, is mainly achieved by the third portion BA3 and the first portion BA1.

[0036] The fixing of the first frame member 52a to the joining member 50c will be described. The position of the first frame member 52a is adjusted relative to the joining member 50c, thereby positioning the first frame member 52a relative to the joining member 50c. At this time, if the barrel 41 and the like are fixed to the first frame member 52a in advance, the first frame member 52a can be positioned while optically measuring the first display unit 20a and the like. Before or after the positioning operation of the first frame member 52a, the adhesive member BA before photo-curing is supplied to the boundary region G2 between the joint portion 50p and the support portion 50q, supplied to the gap G0 between the protrusion 51a and the through hole 51b, and further supplied to the hole 50s. Then, the adhesive member BA is irradiated with curing light, which is, for example, UV light with a wavelength of 340 nm. Specifically, UV light is irradiated from above the through hole 51b and above the hole 50s. As a result, the first portion BA1 corresponding to the gap G0 is cured, the second portion BA2 corresponding to the hole 50s is cured, and the third portion BA3 is cured by the UV light propagating from these portions and the chain reaction of the curing. In other words, the adhesive member BA is cured overall, and the first frame member 52a is fixed to the joining member 50c while maintaining the positioning state of the first frame member 52a relative to the joining member 50c. Note that, since the third portion BA3 utilizes light wraparound, etc., there is a possibility that the curing may be incomplete due to the shadow of the support portion 50q, but the slit-shaped hole 50s can reduce the area ratio.

[0037] The structure for fixing the second frame member 52b, i.e., the second display unit 100b, to the joining member 50c is the same as the structure for fixing the first display unit 100a to the joining member 50c. That is, the structure for fixing the second frame member 52b to the joining member 50c has a through-type fitting structure 51, a light-curing adhesive member BA, and an additional light-transmitting structure TR1. The method for fixing the second frame member 52b to the joining member 50c is the same as the method for fixing the first frame member 52a to the joining member 50c, and therefore a description thereof will be omitted.

[0038] In the fitting structure 51, the gap G0 between the protrusion 51a and the through hole 51b is, for example, about 0.05 mm to 0.1 mm, but can be larger (for example, about 0.7 mm). The diameter of the through hole 51b is about 2.5 mm, but can be larger. The depth or length of the through hole 51b corresponds to the thickness of the support portion 50q or the flat plate portion 57a, and is, for example, about 3 mm, but is not limited to this.

[0039] 6 is a partially enlarged plan view illustrating a modified example of the slit-shaped hole 50s. In this case, the slit-shaped hole 50s functioning as the additional light transmission structure TR1 does not extend in the Z direction (front and rear), but extends in an oblique direction that is intermediate between the Z direction and the X direction. Although not shown, the slit-shaped hole 50s may extend in the X direction (sideways).

[0040] 7 is a partially enlarged plan view illustrating another modified example of the slit-shaped hole 50s. In this case, a cross slit-shaped hole 50s is provided in the support portion 50q of the coupling member 50c. The cross slit-shaped hole 50s also functions as an additional light-transmitting structure TR1.

[0041] In the above description, the support portion 50q of the joining member 50c is disposed above the joint portion 50p of the first frame member 52a, but the support portion 50q of the joining member 50c may be disposed below the joint portion 50p of the first frame member 52a. In this case, the fitting structure 51 and the like shown in FIG. 5 are disposed upside down. Specifically, although not shown, for example, the protrusion 51a is formed to extend downward from the joint portion 50p, the through hole 51b is formed in the support portion 50q at a position corresponding to the protrusion 51a, and the two holes 50s are formed in the support portion 50q so as to sandwich the through hole 51b.

[0042] Fig. 8 shows an example in which the fitting structure 51 etc. shown in Fig. 5 are modified. In this case, the protrusion 51a is formed in the support portion 50q, and the through hole 51b is formed in the joint portion 50p. In response to this change in arrangement, two holes 50s are formed in the joint portion 50p near the fitting structure 51. The UV curing light is irradiated from the lower side, that is, in the -Y direction.

[0043] The first frame member 52a and the second frame member 52b are not limited to being made of metal, and may be made of resin that does not have light transmission properties or resin that has light transmission properties. Conversely, the joining member 50c may be made of resin that does not have light transmission properties or resin that has light transmission properties. For example, even if the frame members 52a and 52b are made of resin that has light transmission properties, if the joining member 50c is made of metal, an additional light transmission structure TR1 is provided in the joining member 50c to ensure that the curing light can easily reach the adhesive member BA.

[0044] Fig. 9 is a perspective view illustrating a state in which the support device 50 is removed from the virtual image display device DD shown in Fig. 3. The first display unit 20a has a first projection optical system 12a and a first combiner 103a in an integrated state, and the second display unit 20b has a second projection optical system 12b and a second combiner 103b in an integrated state.

[0045] In the first projection optical system 12a, the first combiner 103a is fixed by adhesion or the like in an aligned state to the barrel 41. At this time, the upper end 61g of the first combiner 103a is fixed to a pair of protrusions 41f, 41g protruding outward to the left and right from the front upper end of the barrel 41. The barrel 41 of the first projection optical system 12a has a space for accommodating the first image element 11a, and supports the first image element 11a in an aligned state with respect to the projection lens 21 and the like shown in FIG.

[0046] In the second projection optical system 12b, the second combiner 103b is fixed to the barrel 41 by adhesion or the like in an aligned state. At this time, the upper end 61g of the second combiner 103b is fixed to a pair of protrusions 41f, 41g protruding outward to the left and right from the front upper end of the barrel 41. The barrel 41 of the second projection optical system 12b has a space for accommodating the second image element 11b, and supports the second image element 11b in an aligned state with respect to the projection lens 21 and the like shown in FIG.

[0047] In the first display unit 20a, the fastening portion 40f provided on the barrel 41 corresponds to the fastening member 50f shown in Fig. 3, and enables the upper portion 41x of the barrel 41 to be fixed to the first frame 52a. In the second display unit 20b, the fastening portion 40f provided on the barrel 41 corresponds to the fastening member 50f shown in Fig. 3, and enables the upper portion 41y of the barrel 41 to be fixed to the second frame 52b.

[0048] The structure of the barrel 41, i.e., the case CA, will be described with reference to FIG. 10. The barrel 41, i.e., the case CA, includes a barrel body 41a and a barrel cover 41u, houses the first optical member 2a, and holds the second optical member 2b. The barrel body 41a and the barrel cover 41u are formed of a resin material, for example, polycarbonate resin to which a black pigment has been added to impart light blocking properties. The barrel body 41a is a bathtub-shaped container with an open top, and has an injection port 41o at a part of the bottom. The barrel cover 41u is fixed so as to cover the barrel body 41a from above. The barrel body 41a has two side plate members 41c (only one of which is shown), a bottom plate member 41d, a front plate member 41e, and two protrusions 41f, 41g (see FIG. 9). The two side plate members 41c extend substantially parallel to the YZ plane, which is a vertical plane along which the optical axis AX extends, and are spaced apart from each other. The bottom plate member 41d extends substantially along the horizontal XZ plane, and has an injection port 41o at its rear end. The front plate member 41e connects the front end of the bottom plate member 41d to the front ends of the two side plate members 41c.

[0049] On the inside of the side plate member 41c, guide protrusions 45a, 45b, 45c, and 45d having steps are formed as protrusions that support the first lens 21o, the second lens 21p, and the third lens 21q constituting the first optical member 2a, and the prism mirror 22 of the second optical member 2b. The first lens 21o is bonded in a biased and positioned state by the first guide protrusion 45a, and supported by the barrel body 41a. Similarly, the second lens 21p is bonded in a positioned state by the second guide protrusion 45b, and supported by the barrel body 41a, and the third lens 21q is bonded in a positioned state by the third guide protrusion 45c, and supported by the barrel body 41a. The prism mirror 22 is bonded in a positioned state via a protrusion 22t provided on the side surface of the prism mirror 22 by the fourth guide protrusion 45d, and supported by the barrel body 41a.

[0050] The barrel cover 41u is disposed on the opposite side of the bottom plate member 41d and covers the inside of the barrel body 41a to form a storage space IS. The barrel cover 41u includes a top plate 41w and a rear plate 41r. The top plate 41w extends parallel to the XZ plane, and the rear plate 41r is disposed at an angle so as to cover the outside of the reflecting surface 22b of the prism mirror 22 of the second optical member 2b. In the barrel cover 41u, a holder base 41s for positioning, which is lowered by a predetermined height from the surroundings, is formed on the front +Z side, and an insertion opening 41z is formed in front of the holder base 41s. The holder base 41s provided on the barrel cover 41u faces the base plate 31b of the holder 31 for the first image element 11a. The base plate 31b extends horizontally along the holder base 41s and is fixed to the barrel 41 by adhesive while covering a part or all of the insertion opening 41z.

[0051] In the barrel 41, the first image element 11a supported by a support frame 31a extending vertically downward from the base plate 31b of the holder 31 is inserted from above through the insertion opening 41z in the space ISa facing the front plate member 41e, and is fixed in a positioned state.

[0052] The virtual image display device DD of the first embodiment described above includes a first display unit 100a having a first image element 11a, a first projection optical system 12a that projects the image light ML from the first image element 11a, and a first mirror M1 that reflects the image light ML from the first projection optical system 12a, a second display unit 100b having a second image element 11b, a second projection optical system 12b that projects the image light ML from the second image element 11b, and a second mirror M2 that reflects the image light ML from the second projection optical system 12b, The display device includes a connecting member 50c that connects the first display unit 100a and the second display unit 100b, a through-type fitting structure 51 formed between a joint 50p formed on the first display unit 100a and a support portion 50q provided on the connecting member 50c, and a light-curing adhesive member BA that is held between the joint 50p and the support portion 50q, and a light-transmitting structure TR1 is formed in either the joint 50p or the support portion 50q near the fitting structure 51 and between the joint 50p and the support portion 50q.

[0053] In the virtual image display device DD, the light-transmitting structure TR1 is formed between the joint 50p and the support 50q near the fitting structure 51, so that curing light can reach the light-curing adhesive member BA sandwiched and held between the joint 50p and the support 50q through the light-transmitting structure TR1 to promote sufficient curing, thereby increasing the fixing strength of the joint 50p to the support 50q by the adhesive member BA, that is, the attachment strength of the first display unit 100a to the joining member 50c. Similarly, the attachment strength of the second display unit 100b to the joining member 50c can be increased.

[0054] Second Embodiment The virtual image display device of the second embodiment will be described below. Note that the virtual image display device of the second embodiment is a partial modification of the virtual image display device of the first embodiment, and the description of the parts common to the virtual image display device of the first embodiment will be omitted.

[0055] 11, the through hole 51b of the fitting structure 51 has a tapered shape that widens toward the upper side away from the first frame member 52a or the joint portion 50p. That is, the through hole 51b is tapered so that the cross-sectional size becomes larger on the upper side, i.e., the outer side. The slit-shaped hole 50s adjacent to the fitting structure 51 also has a tapered shape that widens toward the upper side away from the first frame member 52a or the joint portion 50p in the horizontal X direction. That is, the slit-shaped hole 50s is tapered so that the cross-sectional size becomes larger on the upper side, i.e., the outer side.

[0056] The taper angle at which the through-hole 51b and the slit-like hole 50s are inclined with respect to the vertical direction is usually an acute angle, but is not limited to this.

[0057] As described above, when the through-holes 51b and the slit-like holes 50s have a tapered shape that widens upward, more UV light can reach the boundary region G2 (see FIG. 5). In other words, even if the support portion 50q is relatively thick, the UV light can easily penetrate or reach the bottom of the through-holes 51b, etc., and curing progresses to the innermost part. This makes it difficult for a semi-cured or uncured portion to be formed in the adhesive member BA, thereby increasing the bonding strength between the joint portion 50p and the support portion 50q and increasing the fixing strength of the first frame member 52a and the second frame member 52b to the joining member 50c.

[0058] Third Embodiment Hereinafter, the virtual image display device of the third embodiment will be described. Note that the virtual image display device of the third embodiment is a partial modification of the virtual image display device of the first embodiment, and the description of the parts common to the virtual image display device of the first embodiment will be omitted.

[0059] As shown in FIG. 12, in the vicinity of the fitting structure 51, four slit-shaped notches 150s are formed instead of slit-shaped holes. In this case, the four notches 150s are elongated in the Z direction across the coupling member 50c. The notches 150s are formed to penetrate the support portion 50q, but are open at the front and rear ends of the support portion 50q corresponding to the ±Z direction. These notches 150s function as additional light-transmitting structures TR1 that allow light to reach the boundary region between the joint portion 50p and the support portion 50q. The notches 150s also have the role of guiding light incident on the side surface of the support portion 50q to the boundary region G2 (see FIG. 5) between the joint portion 50p and the support portion 50q.

[0060] [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.

[0061] The optical members 2a, 2b of the first projection optical system 12a or the second projection optical system 12b are not limited to those shown in the figure, and for example, the number of optical elements constituting the first optical member 2a and the shape of the optical surface can be appropriately changed depending on the purpose of use of the virtual image display device DD, i.e., HMD 200, etc.

[0062] In the above embodiment, a see-through mirror 23 was used that partially reflects the image light ML and partially transmits the outside light OL, but instead of the see-through mirror 23, a mirror that mostly reflects the image light ML and blocks the outside light OL can also be used.

[0063] The projections 51a and through holes 51b constituting the fitting structure 51 are not limited to a cylindrical or columnar shape, but may be rib-like or long hole-like in a specific direction.

[0064] In the second embodiment, the through hole 51b and the slit-like hole 50s have a tapered shape, but a step that widens toward the upper side may be provided.

[0065] As shown in Fig. 13, instead of the slit-shaped hole 50s or notch 150s shown in Fig. 5 etc., a gap-shaped recess 250s that does not penetrate vertically and separates the joint portion 50p and the support portion 50q may be provided. This recess 250s may not penetrate vertically or horizontally, but may penetrate in the depth direction (Z direction perpendicular to the paper surface). It is desirable to narrow the width of the recess 250s (width in the X direction horizontal on the paper surface) so as not to reduce the fixing strength. Even if the width of the recess 250s is narrowed, if the depth is increased, it becomes easier for light to reach the boundary region G2.

[0066] In the above embodiment, the first display unit 20a and the second display unit 20b (specifically, the barrel 41) are fixed to the first frame member 52a and the second frame member 52b, but a light guide plate and an optical system associated therewith may be fixed to the frame members 52a and 52b. Here, the light guide plate guides the image light emitted from the image element to a position facing the pupil while reflecting it on its inner surface, and causes the image light to enter the inside from an entrance surface provided at the end, or causes the image light to enter the inside via a diffraction element provided in a part of the parallel plate that constitutes the light guide plate.

[0067] In the above description, it is assumed that the virtual image display device DD is used by being mounted on the head, but the virtual image displays 100A and 100B 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.

[0068] One of the first display unit 100a and the second display unit 100b may be omitted. In this case, for example, since only the first display unit 100a is supported by the support device 50, the connecting member 50c and the frame member 52b can be integrated, and the frame member 52b has a simple structure that does not support the optical system and is connected to the mounting device 100C.

[0069] A virtual image display device in a specific embodiment includes a first display unit having a first image element, a first projection optical system that projects image light from the first image element, and a first mirror that reflects the image light from the first projection optical system, a connecting member connected to the first display unit, a through-type fitting structure formed between a joint formed on the first display unit and a support provided on the connecting member, and a photo-curing adhesive member held between the joint and the support, and a light-transmitting structure is formed in either the joint or the support near the fitting structure and between the joint and the support.

[0070] In the above virtual image display device, a light-transmitting structure is formed near the fitting structure and between the joint and the support, so that curing light can reach the light-curing adhesive member held between the joint and the support through the light-transmitting structure, promoting sufficient curing, and increasing the fixing strength of the joint to the support by the adhesive member, i.e., the attachment strength of the first display unit to the connecting member.

[0071] In a specific embodiment of the virtual image display device, the light-transmitting structure is provided on either the joint portion or the support portion, and allows light to reach a boundary region between the joint portion and the support portion. The boundary region is filled with an adhesive member.

[0072] In a specific embodiment of the virtual image display device, the light-transmitting structure is provided so as to penetrate one of the joint portion and the support portion to expose the other. In this case, the adhesive material can be efficiently cured in the exposed portion and its surroundings.

[0073] In a specific embodiment of the virtual image display device, the light-transmitting structure is provided so as to expose the inner region of the boundary region, whereby the adhesive can be cured efficiently in the inner region and its periphery.

[0074] In a specific embodiment of the virtual image display device, the fitting structure has a pin-shaped protrusion and a through hole that fits into the protrusion. By combining the protrusion and the through hole, it is possible to easily adjust the position of the first display unit relative to the connecting member.

[0075] In a virtual image display device according to a specific embodiment, the protrusion is formed on the joint portion and the through hole is formed on the support portion. Conversely, the protrusion may be formed on the support portion and the through hole may be formed on the joint portion.

[0076] In a specific embodiment of the virtual image display device, a gap is provided between the protrusion and the through hole in the fitting structure, which allows the relative arrangement of the first display unit and the connecting member to be adjusted. With this, it becomes possible to fix them while positioning them by filling the gap between the protrusion and the through hole with an adhesive and curing it in a state where the position of the first display unit is adjusted with respect to the connecting member.

[0077] In a specific embodiment of the virtual image display device, the connecting member is made of metal. If the connecting member is made of metal, the connecting member cannot be made light-transmitting, but the strength of the connecting member can be increased, and the structural precision can be improved while the connecting member is lightweight.

[0078] In a specific embodiment of the virtual image display device, the joint is made of metal. If the joint is made of metal, the joint cannot be made light-transmitting, but the strength of the joint can be increased, and the structural precision can be improved while the joint is lightweight.

[0079] In a specific embodiment of the virtual image display device, the adhesive is filled into the gap formed in the light-transmitting structure. In this case, by irradiating curing light from the light-transmitting structure to the boundary region between the joint and the support, the adhesive filled into the gap in the light-transmitting structure and the adhesive that has reached the boundary region between the joint and the support can be cured.

[0080] In a virtual image display device according to a specific embodiment, the light transmitting structure has a slit-shaped hole or a notch. The slit-shaped hole or the notch is relatively easy to process, and the strength of the joint or the support part can be easily maintained.

[0081] In a specific embodiment of the virtual image display device, the light transmission structure has a plurality of slit-shaped holes or notches. If a large number of slit-shaped holes or notches are formed, it becomes easy for the curing light to reach the boundary region between the joint part and the support part.

[0082] In a specific embodiment of the virtual image display device, the plurality of slit-shaped holes or notches are provided so as to sandwich the fitting structure. In this case, it becomes possible to achieve a well-balanced fixation around the fitting structure.

[0083] In a virtual image display device according to a specific embodiment, the slit-shaped hole or notch has a tapered shape in which the cross-sectional size increases on the outer side.

[0084] In a specific embodiment, the virtual image display device further includes a second display unit having a second image element, a second projection optical system that projects image light from the second image element, and a second mirror that reflects the image light from the second projection optical system, and the connecting member connects the first display unit and the second display unit.

[0085] In a specific embodiment of the virtual image display device, the structure for fixing the second display unit to the connecting member is the same as the structure for fixing the first display unit to the connecting member, and includes a through-type fitting structure, a light-curing adhesive member, and an additional light-transmitting structure, thereby increasing the attachment strength of the second display unit to the connecting member. [Explanation of symbols]

[0086] 11a, 11b...image element, 21...projection lens, 22...prism mirror, 23...see-through mirror, 123...optical appearance part, 23a...transmissive reflective film, 23b...substrate, 31...holder, 40f...fastening part, 41...barrel, 41a...barrel main body, 41f, 41g...projection part, 41o...injection port, 41u...barrel cover, 41z...insertion port, 50...support device, 50c...coupling member, 50f...fastening member, 50p...jointing part, 50q...support part, 50s...hole, 150s...notch, 51...fitting structure, 51a...projection, 51b...through hole, 52a, 52b...frame member, 55a... Flat plate portion, 55b, 55c...reinforcing protrusions, 57a...flat plate portion, 57b...reinforcing protrusions, 61...support plate, 61g...upper end, 88...display control device, 90...user terminal, 100...optical unit, 100A, 100B...virtual image display device, 100C...mounting device, 102a, 102b...display drive unit, 103a, 103b...combiner, AX...optical axis, BA...adhesive member, CA...case, DD...virtual image display device, EP...exit pupil, G0...gap, G2...boundary area, IS...storage space, JS...connecting portion, ML...image light, OL...external light, PP...pupil position, RE...recess, TR1...additional light transmission structure

Claims

1. a first display unit including a first image element, a first projection optical system that projects image light from the first image element, and a first mirror that reflects the image light from the first projection optical system; A coupling member connected to the first display unit; a through-type fitting structure formed between a joint portion formed on the first display unit and a support portion provided on the connecting member; a photocurable adhesive member held between the joint portion and the support portion, a light transmitting structure is formed in the vicinity of the fitting structure and between the joint portion and the support portion in either one of the joint portion and the support portion; Virtual image display device.

2. the light transmitting structure is provided on either the joint portion or the support portion, and allows light to reach a boundary region between the joint portion and the support portion. The virtual image display device according to claim 1 .

3. The light transmitting structure is provided so as to penetrate one of the joint portion and the support portion to expose the other. The virtual image display device according to claim 2 .

4. The light transmitting structure is provided so as to expose an inner region of the boundary region. The virtual image display device according to claim 2 .

5. The fitting structure has a pin-shaped protrusion and a through hole into which the protrusion fits. The virtual image display device according to claim 1 .

6. The protrusion is formed in the joint portion, and the through hole is formed in the support portion. The virtual image display device according to claim 5 .

7. In the fitting structure, a gap is provided between the protrusion and the through hole, which allows adjustment of a relative position between the first display unit and the connecting member. The virtual image display device according to claim 5 .

8. The coupling member is made of metal. The virtual image display device according to claim 1 .

9. The joint is made of metal. The virtual image display device according to claim 1 .

10. The adhesive member is filled in a gap formed in the light-transmitting structure. The virtual image display device according to claim 1 .

11. The light transmitting structure has a slit-shaped hole or a notch. The virtual image display device according to claim 10.

12. The light-transmitting structure has a plurality of slit-shaped holes or notches. The virtual image display device according to claim 10.

13. The plurality of slit-shaped holes or notches are provided so as to sandwich the fitting structure. The virtual image display device according to claim 12.

14. The slit-like hole or notch has a tapered shape in which the cross-sectional size increases on the outside. The virtual image display device according to claim 11 or 12.

15. a second display unit including a second image element, a second projection optical system that projects image light from the second image element, and a second mirror that reflects the image light from the second projection optical system; The connecting member connects the first display unit and the second display unit. The virtual image display device according to claim 1 .

16. A structure for fixing the second display unit to the connecting member is the same as a structure for fixing the first display unit to the connecting member, and includes a through-type fitting structure, a light-curing adhesive member, and an additional light-transmitting structure. The virtual image display device according to claim 1 .

Images