JP2019066813A - Light guide device and display device - Google Patents

Abstract

To provide a light guide device capable of suppressing generation of a ghost or the like due to deflection between a first light guide body and a second light guide body when reflecting image light by half mirrors provided between the first light guide body and the second light guide body, and a display device.SOLUTION: A light guide device 50 used for a display device 100 has a plurality of first half mirrors 81 between a first light guide body 60 and a second light guide body 70. The first half mirrors 81 are formed on first surfaces 61 out of the first surfaces 61 extending in a first direction A and a second surface 62 extending in a second direction B in the first light guide body 60. The first light guide body 60 comprises a third surface 63 overlapping with the second surface 62 in a direction in a third direction D in which two first surfaces 61 positioned at both sides of the second surface 62 do not overlap with each other among the first surfaces 61 and the second surface 62. The third surface 63 extends in a direction different from the first direction A.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a light guide device that reflects incident light in a predetermined direction and emits the light, and a display device.

  There have been proposed display devices in which image light emitted from an image light emitting device is made incident by the eyes of the observer via a light guiding device (see Patent Documents 1 and 2). In principle, such a light guiding device has a configuration in which a reflective layer 80 is provided between the first light guiding member 60 and the second light guiding member 70 as shown in FIG. More specifically, the first light guide 60 has a plurality of first surfaces 61, each extending along the first direction A, and each adjacent first surface 61 in the first direction. A plurality of second surfaces 62 extending along the intersecting second direction B is provided, and the reflective layer 80 is formed on the first surface 61. Therefore, as shown by arrow L1 in FIG. 20, in the first light guide 60, the image light L0 traveling toward the reflective layer 80 can be reflected toward the observer's eye by the reflective layer 80.

  In Patent Documents 1 and 2, adopting a half mirror as the reflective layer 80 is proposed, and in this case, external light can reach the observer's eye via the reflective layer 80 (half mirror). In addition, the aspect which formed the reflecting layer 80 (half mirror) in a part of 1st surface 61 is proposed by patent document 1, 2, and according to this aspect, the reflecting layer 80 is the 1st surface 61. External light can reach the observer's eye through the unformed area.

Unexamined-Japanese-Patent No. 2017-32924 Unexamined-Japanese-Patent No. 2016-110108

  However, when a half mirror is used as the reflective layer 80, as shown by an arrow L2 in FIG. 20, a part of the image light L0 passes through the reflective layer 80, then passes through the second surface 62, and then is adjacent The light is reflected toward the observer's eye by the reflection layer 80. At that time, when the refractive index of the first light guide 60 and the refractive index of the second light guide 70 are different, refraction at the first surface 61, refraction at the second surface 62, and the first light guide 60. Under the influence of refraction at the end face 65, the light beam indicated by the arrow L2 is emitted toward the observer's eye from a direction different from the light beam indicated by the arrow L1. As a result, the observer recognizes a ghost due to the light beam indicated by the arrow L2.

  Such a problem can be solved by making the refractive index n1 of the first light guide 60 and the refractive index n2 of the second light guide 70 the same. However, for example, in the case where 1920 pixels are displayed at a horizontal angle of view of ± 20 ° when the inclination angle α of the reflective layer 80 is 15 ° and the light beam angle θ is 30 °, the ghost should be 1 pixel or less. The difference between the refractive index n1 of the first light guide 60 and the refractive index n2 of the second light guide 70 needs to be 0.012% or less. And a great obstacle in selecting the material used for the second light guide 70.

  In addition, the aspect by which the 3rd surface extended in the direction different from the 1st direction A was formed between the 1st surface 61 and the 2nd surface 62 in Drawing 4 (a) of patent documents 1 is described. There is. However, Patent Document 1 does not at all describe the relationship between the third surface and the above-mentioned ghost. Moreover, as shown in FIG. 2 of Patent Document 1, in order to emit the image light L0 toward the observer's eye by the reflective layer 80, according to the aspect described in FIG. In this case, when light transmitted through the reflective layer 80 is reflected toward the eye of the observer by the adjacent reflective layer 80, refraction at the first surface 61, the second surface Under the influence of the refraction at 62 and the refraction at the end face 65 of the first light guide 60, a ghost occurs.

  Although Patent Document 2 proposes that a light absorbing layer is applied to the second surface 62, the first surface 61 and the second surface 62 can be used with respect to a wall surface perpendicular to the second surface 62. It is not easy to apply the light absorbing layer to the back of the gap between the two.

  In view of the above problems, it is an object of the present invention to provide a first light guide and a second light guide in the case where image light is reflected by a half mirror provided between the first light guide and the second light guide. It is an object of the present invention to provide a light guide device and a display device capable of suppressing the occurrence of ghosts and the like due to refraction between the two light guides.

  In order to solve the above-mentioned subject, one mode of a light guide concerning the present invention has the adjacent 1st among a plurality of 1st surfaces which extend along a 1st direction, and the 1st above-mentioned plurality of the 1st surfaces, respectively. A plurality of second surfaces extending along a second direction which intersects the first direction between each one surface is provided on one side in the thickness direction, and an end surface is provided on the other side in the thickness direction. A first light guide, a plurality of first half mirrors each in contact with the plurality of first surfaces, a plurality of first half mirrors, and a second light guide in contact with the plurality of second surfaces; And the first light guide is positioned on each side of the second surface between the adjacent first surface and the second surface among the plurality of first surfaces and the plurality of second surfaces. A plurality of third surfaces, each overlapping the second surface in a direction along a third direction in which the two first surfaces do not overlap with each other, each of the plurality of third surfaces being Characterized in that it extends to the serial first direction different from directions. In the present invention, “half mirror” means a layer having reflectivity and transparency, and is not limited to the case where the reflectivity is 50%.

  In the present invention, the light traveling toward the first surface in the first light guiding body travels toward the first surface inside the first light guiding body, and a portion of the light is guided by the second half mirror through the first half mirror. The light is reflected to the side opposite to the light and emitted from the end face. At that time, another part of the light passes through the first half mirror. Also, part of the external light that has entered the first half mirror from one side in the thickness direction is transmitted through the first half mirror and emitted from the end face. Here, the first light guide includes a third surface extending in a direction different from the first direction between the first surface and the second surface, and the adjacent first surfaces are the aforementioned ones. It does not overlap in the third direction. Therefore, the light transmitted through the first half mirror is transmitted through the second surface, and then enters the third surface without being incident on the adjacent first surface (first half mirror). The transmitted light is emitted in a direction different from the light reflected by the first half mirror. Therefore, when the light guide device is used for a display device, even in the case where the refractive index of the first light guide and the refractive index of the second light guide are different, in the image light transmitted through the first half mirror Even if refraction at the first surface, refraction at the second surface, refraction at the end face, and the like occur, it is difficult for the observer to recognize a ghost due to such refraction.

  In the present invention, it is possible to adopt an aspect in which the refractive index of the first light guide and the refractive index of the second light guide are different.

  In the present invention, a mode is provided in which a plurality of second half mirrors, each in contact with the plurality of third surfaces, are provided between the first light guide and the second light guide. it can. According to this aspect, a part of the external light that has entered the third surface from one side in the thickness direction is transmitted through the second half mirror and emitted from the end surface. Further, even if the light transmitted through the first half mirror and the second surface reaches the third surface, it is possible to suppress the light from being emitted from the light guiding device to one side in the thickness direction.

  In the present invention, it is possible to adopt an aspect in which the reflectance of the first half mirror and the reflectance of the second half mirror are equal. According to this aspect, it is possible to make the external light passing through the light guide device uniform. In addition, if the outside light is uniform, diffraction is unlikely to occur, so the observer can observe the clear outside light.

  In the present invention, an aspect may be adopted in which the reflectance of the first half mirror and the reflectance of the second half mirror are different. For example, when the reflectance of the second half mirror is smaller than the reflectance of the first half mirror, the light amount of the ghost can be suppressed.

  In the present invention, among the plurality of first surfaces and the plurality of second surfaces, the plurality of third surfaces each have the thickness of the first surface between the adjacent first surface and the second surface. The aspect provided between each one end of the longitudinal direction and the end of the one side of the thickness direction of the second surface can be adopted. According to this aspect, the thickness is greater than in the case where the third surface is provided between the other end of the first surface in the thickness direction and the other end of the second surface in the thickness direction. Since the extension dimension of the first surface on the other side of the direction can be increased, the amount of light reflected from the first half mirror and emitted from the end surface can be increased.

  In the present invention, each of the first light guides may be disposed between the first surface and the second surface adjacent to each other among the plurality of first surfaces and the plurality of second surfaces. A fourth surface extending in the third direction between the other end of the thickness direction and the other end of the second surface in the thickness direction Can be adopted. According to this aspect, since the extension distance of the third surface can be shortened, the extension dimension of the first surface on one side in the thickness direction can be lengthened. Therefore, the amount of light reflected by the first half mirror and emitted from the end face can be increased.

  In the present invention, a mode is provided in which a plurality of third half mirrors, each in contact with the plurality of fourth surfaces, are provided between the first light guide and the second light guide. it can.

  In the present invention, it is possible to adopt an aspect in which the plurality of third surfaces are parallel to the direction in which the plurality of first surfaces and the plurality of second surfaces are arranged.

  In the present invention, each of the plurality of third surfaces may be a slope inclined at an angle with respect to the direction in which the plurality of first surfaces and the plurality of second surfaces are arranged.

  In the present invention, each of the plurality of third surfaces is a central portion between the first boundary with the first surface and the second boundary with the second surface from the first boundary and the second boundary. A mode may be adopted in which the protruding convex curved surface or the central portion is a concave curved surface recessed from the first boundary and the second boundary.

  In the present invention, it is possible to adopt an aspect in which the third direction is a direction in which a light beam incident on the first half mirror travels through the first half mirror and the second surface. According to this aspect, the light transmitted through each of the first half mirrors can be reliably reflected by the third surface in a direction different from the light reflected by the first half mirrors.

  In the present invention, it is possible to adopt an aspect in which the positions in the thickness direction of the plurality of first surfaces change along the arrangement direction of the plurality of first surfaces with reference to the end face.

  In the present invention, a mode is provided in which a plurality of fourth half mirrors, each in contact with the plurality of second surfaces, is provided between the first light guide and the second light guide. it can.

  In the present invention, it is possible to adopt an aspect in which each of the plurality of first surfaces is a concave surface which is recessed toward the second light guide. According to this aspect, it is possible to exhibit such power as to condense the light incident on the first surface.

  In the present invention, the plurality of first surfaces and the plurality of first surfaces may be concave surfaces which are recessed in the direction in which the plurality of first surfaces and the plurality of second surfaces are arranged. It is possible to adopt an aspect in which the second surface extends while being curved in a direction perpendicular to the direction in which the second surface is arranged. According to this aspect, it is possible to exert the power of collecting the light incident on the first surface in the direction orthogonal to the direction in which the plurality of first surfaces and the plurality of second surfaces are arranged.

  In this case, the second surface may adopt an aspect of being curved along the first surface. In the case of this aspect, since the entire light guide device is curved, the light guide device is thick in the direction in which the first light guide and the second light guide overlap even if the first surface is curved. Can be suppressed.

  In the present invention, it is possible to adopt an aspect in which the curvature of each of the plurality of first surfaces changes along the direction in which the plurality of first surfaces and the plurality of second surfaces are arrayed. According to this aspect, at each position in the direction in which the plurality of first surfaces and the plurality of second surfaces are arranged, each of the plurality of first surfaces can exhibit power for appropriately condensing light. .

  One aspect of a display device provided with a light guiding device according to the present invention includes the light guiding device and an image light emitting device that emits image light, and the plurality of the image lights are included in the first light guiding body. It injects from said 3rd direction with respect to each of the 1st surface of a.

  In the aspect of the invention, the image light may be introduced into the first light guide from the end face of the first light guide.

  In the present invention, the optical path from the image light emitting device toward the first light guide includes a light guiding optical system for guiding the image light emitted from the image light emitting device to the first light guide. Can be adopted.

BRIEF DESCRIPTION OF THE DRAWINGS The external view which shows one aspect | mode of the external appearance of the display apparatus which concerns on Embodiment 1 of this invention. FIG. 2 is a plan view of an optical system of a display unit shown in FIG. 1. Explanatory drawing of the light guide device shown in FIG. Explanatory drawing which expands and shows a part of light guide device shown in FIG. Explanatory drawing of the light guide device based on Embodiment 2 of this invention. Explanatory drawing of the light guide device based on Embodiment 3 of this invention. Explanatory drawing of the light guide device based on Embodiment 4 of this invention. Explanatory drawing of the light guide device based on Embodiment 5 of this invention. Explanatory drawing of the light guide device based on Embodiment 6 of this invention. Explanatory drawing of the light guide device based on Embodiment 7 of this invention. Explanatory drawing of the light guide device based on Embodiment 8 of this invention. FIG. 12 is an explanatory view showing a first surface and the like of the light guide device shown in FIG. 11 in an enlarged manner. Explanatory drawing of the light guide device based on Embodiment 9 of this invention. FIG. 14 is an explanatory view showing a first surface and the like of the light guide device shown in FIG. 13 in an enlarged manner. FIG. 14 is an explanatory view showing a configuration of a third surface and the like of the light guide device shown in FIG. 13. Explanatory drawing which shows a structure of 3rd surface etc. of the light guide device which concerns on Embodiment 10 of this invention. Explanatory drawing of the light guide device based on Embodiment 11 of this invention. Explanatory drawing of the light guide device based on Embodiment 12 of this invention. Explanatory drawing of the display apparatus based on Embodiment 13 of this invention. Explanatory drawing of the light guide device which concerns on the reference example of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following drawings, in order to make each layer and each member have a recognizable size, the scale and angle of each layer and each member are made different from actual.

Embodiment 1
(overall structure)
FIG. 1 is an external view showing an aspect of the appearance of a display device 100 according to Embodiment 1 of the present invention. FIG. 2 is a plan view of the optical system of the display unit 10 shown in FIG. In FIGS. 1 and 2, Z is attached in the front-rear direction, X is attached in the lateral direction, and Y is attached in the vertical direction. Further, Z1 is attached to the front side, Z2 is attached to the rear side, Y1 is attached to the upper side, and Y2 is attached to the lower side. Further, in FIG. 2 showing the display unit 10a for the right eye, X1 is attached to the right side (ear side) and X2 is attached to the left side (nose side). Further, in FIG. 2, as the image light L0 emitted from the image light emitting device 20, a light ray at the center of the angle of view and light rays at both ends of the angle of view are shown.

  The display device 100 shown in FIG. 1 is a head-mounted display device such as a see-through eyeglass display, and has a display unit 10a for the right eye that causes the image light L0a to be incident on the right eye Ea, and a left And a display unit 10b for the left eye to be incident on the eye Eb. The display device 100 has a frame 90 for holding the display units 10a and 10b, and the frame 90 is mounted on the head of the observer. The frame 90 has a front portion 91 for holding a light guide device 50a for the right eye and a light guide device 50b for the left eye, which will be described later, and the right side 92a of the frame 90 and the left side 92b Each of them holds an image light emitting device 20 and the like which will be described later with reference to FIG.

  The display unit 10a for the right eye and the display unit 10b for the left eye are arranged symmetrically with the same configuration. Therefore, in the following description, it demonstrates centering on the display part 10a for right eyes, and description is abbreviate | omitted about the display part 10b for left eyes. In the following description, the display unit 10 a for the right eye and the display unit 10 b for the left eye will be described as the display unit 10 without distinction.

  As shown in FIG. 2, the display unit 10 (display unit 10 a) directs the image light emitting device 20 for emitting the image light L0 and the image light L0 emitted from the image light emitting device 20 to the eye E of the observer. And a light guide device 50 for emitting light. In addition, the display unit 10 has a light guiding optical system 30 for directing the image light L0 emitted from the image light emitting device 20 to the light guiding device 50 in the light path from the image light emitting device 20 to the light guiding device 50. ing. The light guiding device 50 is disposed on the front side Z1 of the eye E, the image light emitting device 20 is disposed on the side of the head, and the light guiding optical system 30 is disposed on the front side of the image light emitting device 20.

  The image light emitting device 20 can adopt an aspect provided with a display panel 21 such as an organic electroluminescence display element. According to this aspect, it is possible to provide the display unit 10 capable of displaying a small image with high image quality. Further, the image light emitting device 20 may adopt an aspect including an illumination light source (not shown) and a display panel 21 such as a liquid crystal display element that modulates the illumination light emitted from the illumination light source. According to this aspect, since the illumination light source can be selected, there is an advantage that the degree of freedom of the wavelength characteristic of the image light L0 is expanded. Here, the image light emitting device 20 can adopt an aspect having one display panel 21 capable of color display. Further, the image light emitting device 20 may adopt an aspect having a plurality of display panels 21 corresponding to the respective colors, and a combining optical system for combining the image light of the respective colors emitted from the plurality of display panels 21. Furthermore, the image light emitting device 20 may adopt an aspect in which laser light is modulated by a micro mirror device.

  The light guide optical system 30 has, for example, a plurality of lenses 31, 32 and 33 and a mirror 35. The plurality of lenses 31, 32, and 33 constitute a projection system, and the lens surfaces of the lenses 32, 33 are, for example, free-form surfaces. The mirror 35 projects the image light L 0 transmitted through the lenses 31, 32 and 33 toward the light guiding device 50 from obliquely behind. According to the light guide optical system 30 (projection optical system), the central optical axis of the image light L0 emitted from the center of the image light and the end of the angle of view can be made parallel. The light guide device 50 is a plate-like member whose thickness direction T is directed in the front-rear direction Z.

(Configuration of light guide device 50)
FIG. 3 is an explanatory view of the light guide device 50 shown in FIG. FIG. 4 is an explanatory view showing a part of the light guide device 50 shown in FIG. 2 in an enlarged manner. As shown in FIGS. 3 and 4, the light guide device 50 is joined to the plate-like first light guide 60 at one side T1 of the first light guide 60 in the thickness direction T by an adhesive or the like. The first light guide 60 and the second light guide 70 extend in the lateral direction X. The first light guide 60 is made of a light transmitting member having a refractive index of n1, and the second light guide 70 is made of a light transmitting member having a refractive index of n2. In the present embodiment, the first light guide 60 and the second light guide 70 are made of a translucent resin, and the refractive index n1 of the first light guide 60 and the refractive index n2 of the second light guide 70 Is different.

  The first light guide 60 has a plurality of first surfaces 61 extending in the first direction A, and a plurality of first surfaces 61 that are adjacent to each other among the first surfaces 61. A plurality of second surfaces 62 extending along a second direction B intersecting the one direction A is provided on one side T1 in the thickness direction T, and has an end face 65 on the other side T2 in the thickness direction T There is. An antireflective layer 51 is formed on the end face 65. The end face 65 is parallel to a direction C (lateral direction X) in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged, and a first direction A in which the first surface 61 extends, and a second surface The second direction B in which the 62 extends is a direction intersecting the end surface 65. The second surface 62 may be either parallel to the vertical direction Y or inclined to the vertical direction Y.

  In the light guide device 50, a plurality of first half mirrors 81 that are in contact with the plurality of first surfaces 61 are provided, and the second light guide 70 includes a plurality of first half mirrors 81 and a plurality of second half mirrors 81. It is arranged in contact with the surface 62. The second light guide 70 includes an end surface 75 on one side T1 in the thickness direction T, and the end surface 75 is a direction C in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged (horizontal direction Parallel to X).

  In the display unit 10 configured in this manner, the image light L0 emitted from the light guide optical system 30 is directed to the end face 65 of the first light guide 60 of the light guide device 50 in the lateral direction X on one side X1 (ear It proceeds obliquely from the side) to the other side X2 (nose side) and enters from the end face 65. In the light guide device 50, the image light L0 incident from the end face 65 of the first light guide 60 travels in an oblique direction with respect to the end face 65 inside the first light guide 60, and the first face 61 (first The light is incident on the half mirror 81). Therefore, a part of the image light L0 is reflected by the first half mirror 81 toward the opposite side to the second light guide 70 as shown by the arrow L1, and from the end face 65 toward the eye E of the observer It is emitted. Thus, the observer can recognize the image.

  Therefore, the first surface 61 is inclined in the direction in which one side X1 in the lateral direction X is separated from the end face 65 and the other side X2 in the lateral direction X approaches the end face 65. Further, as shown in FIG. 2, in the image light L 0, the light ray at the center of the angle of view is incident on the center portion in the lateral direction X of the end face 65 and The light is emitted in the orthogonal direction and reaches the eye E. On the other hand, in the image light L0, the light ray at the end of the angle of view is incident on the end of the end face 65 in the lateral direction X and is oblique to the end face 65 from the end in the lateral direction X It is emitted in the direction and reaches the eye E. Accordingly, in FIG. 4, the inclination angle α formed by the plurality of first surfaces 61 with the end surface 65 is larger on the other side X2 than on the one side X1 in the lateral direction X. However, the angle β formed by the plurality of second surfaces 62 with the end surface 65 is constant in the lateral direction X. Therefore, in the present embodiment, the “direction along the first direction A” is different from the plurality of first surfaces 61, while the “direction along the second direction B” is the same in the plurality of second surfaces 62. .

  In the light guiding device 50, a part of the external light incident on the first half mirror 81 from the one side T1 (the second light guiding body 70) in the thickness direction T is a first light as indicated by an arrow L3. The light passes through the half mirror 81 and is emitted from the end face 65 toward the eye E of the observer. Therefore, the observer can recognize the appearance of the outside world.

(Configuration of third surface 63)
In the light guiding device 50 configured as described above, in the present embodiment, as shown in FIG. 4, the first light guiding body 60 is the first adjacent one of the plurality of first surfaces 61 and the plurality of second surfaces 62. Between the surface 61 and the second surface 62, the two first surfaces 61 located on both sides of the second surface 62 do not overlap with each other in the first direction A and the second direction B. In the direction along the third direction D, a plurality of third surfaces 63 that overlap with the second surface 62 are provided. Also, the plurality of third surfaces 63 extend in a direction different from the first direction A.

  In the present embodiment, each of the plurality of third surfaces 63 is a portion of the first surface 61 between the adjacent first surface 61 and second surface 62 among the plurality of first surfaces 61 and the plurality of second surfaces 62. It is provided between the end 611 of the one side T1 in the thickness direction T and the end 621 of the one side T1 of the second surface 62 in the thickness direction T. The plurality of third surfaces 63 are parallel to the direction C in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged. That is, the plurality of third surfaces 63 are parallel to the end face 65 of the first light guide 60 and the end face 75 of the second light guide 70, respectively.

  In the light guide device 50 configured in this manner, the third direction D (the direction in which the second surface 62 and the third surface 63 overlap) is a direction in which the image light L0 is incident on each of the plurality of first half mirrors 81. After the image light L0 passes through the first half mirror 81, it travels through the second surface 62 in the same direction as it travels.

  In the present embodiment, a plurality of second half mirrors 82 which are in contact with the plurality of third surfaces 63 are provided between the first light guide 60 and the second light guide 70. Therefore, the second light guide 70 is disposed in contact with the plurality of first half mirrors 81, the plurality of second surfaces 62, and the plurality of second half mirrors 82. The second half mirror 82 and the first half mirror 81 are connected. In the present embodiment, the first half mirror 81 and the second half mirror 82 have the same layer configuration, and their reflectances are equal. For this reason, the external light shown by arrow L3 can be made uniform. In addition, if the outside light is uniform, diffraction is unlikely to occur, so the observer can observe the clear outside light.

  In the manufacturing process of the light guide device 50 configured as described above, after the first light guide 60 including the first surface 61, the second surface 62, and the third surface 63 is formed by molding, a photolithography technique is used. The first half mirror 81 and the second half mirror 82 are selectively formed to cover the first surface 61 and the third surface 63. Next, after a translucent resin is provided to cover the first half mirror 81, the second surface 62, and the second half mirror 82, the resin is solidified to form the second light guide 70. Next, the surface of the second light guide 70 opposite to the first light guide 60 is flattened to form an end surface 75. Each of the first half mirror 81 and the second half mirror 82 is made of a dielectric multilayer film or a metal thin film such as an aluminum thin film. In the present embodiment, each of the first half mirror 81 and the second half mirror 82 is made of a dielectric multilayer film.

  In addition, after pressing a mold provided with a molding surface corresponding to the first surface 61, the second surface 62, and the third surface 63 against the translucent resin, the resin is solidified to form a first light guide. A method of forming 60 may be employed. Also in this case, the first half mirror 81 and the second half mirror 82 are selectively formed so as to cover the first surface 61 and the third surface 63 using a photolithographic technique. Next, a translucent resin is provided to cover the first half mirror 81, the second surface 62, and the second half mirror 82, and the resin is solidified to form the second light guide 70. Next, the surface of the second light guide 70 opposite to the first light guide 60 is flattened to form an end surface 75.

(Main effects of this form)
As described above, in the light guide device 50 and the display unit 10 (display device 100) of the present embodiment, the first light guide 60 of the light guide device 50 intersects the first direction A and the second direction B. The third surface 63 extending in the direction different from the first direction A is provided in the overlapping region in the third direction D, and the adjacent first surfaces 61 do not overlap in the third direction D. Therefore, a part of the image light L0 incident on the first surface 61 passes through the first half mirror 81 and then passes through the second surface 62, and then the adjacent first surface 61 (first half mirror 81) And the third surface 63. Therefore, the light transmitted through the first half mirror 81 is emitted in a direction different from the light reflected by the first half mirror 81 as shown by the arrow L2, and does not enter the eye E of the observer. Therefore, even when the refractive index n1 of the first light guide 60 and the refractive index n2 of the second light guide 70 are different, the image light L0 transmitted through the first half mirror 81 is formed on the first surface 61 Even if refraction of the second surface 62, refraction at the end face 65, and the like occur, it is difficult for the observer to recognize the ghost due to the refraction.

  Further, since the second half mirror 82 is provided on the third surface 63, part of the external light that has entered the third surface 63 from the one side T1 in the thickness direction T is transmitted through the second half mirror 82. Then, the light is emitted from the end face 65 of the first light guide 60 and reaches the eye of the observer. Further, even if the image light L0 transmitted through the first half mirror 81 and the second surface 62 reaches the third surface 63, such light is emitted from the light guiding device 50 to one side T1 in the thickness direction T. Can be suppressed.

  The third surface 63 is provided between the end 611 of the one side T1 in the thickness direction T of the first surface 61 and the end 621 of the one side T1 of the second surface 62 in the thickness direction T. ing. Therefore, the third surface 63 is provided between the end 612 of the other side T2 in the thickness direction T of the first surface 61 and the end 622 of the other side T2 of the second surface 62 in the thickness direction T. The extension dimension of the first surface 61 on one side T1 in the thickness direction T can be made longer than in the case described above. Therefore, the amount of light reflected by the first half mirror 81 and emitted from the end face 65 can be increased.

  In the present embodiment, although the entire area overlapping with the second surface 62 in the third direction D is the third surface 63, a part of the area overlapping with the second surface 62 in the third direction D is the third surface 63 Even in this case, the occurrence of ghost can be reduced. For example, in the case where use in a bright environment is assumed, the ratio of the brightness of the ghost to the external environment decreases, so a part of the area overlapping the second surface 62 in the third direction D is the third surface 63 By doing this, the occurrence of ghost can be sufficiently reduced. On the other hand, when used in a dark environment, the ghost tends to be noticeable, so it is preferable to use the entire third region 63 overlapping the second surface 62 in the third direction D as in this embodiment. . However, when the third surface 63 is a range wider than the region overlapping the second surface 62 in the third direction D, the image is dark, so the region overlapping the second surface 62 in the third direction D is the same or narrow. It is preferable to set the range to the third surface 63.

Modification 1 of Embodiment 1
In the first embodiment, the reflectance of the first half mirror 81 and the reflectance of the second half mirror 82 are equal, but the reflectance of the first half mirror 81 and the reflectance of the second half mirror 82 are different. It is also good. For example, when the reflectance of the second half mirror 82 is smaller than the reflectance of the first half mirror 81, it is possible to suppress the light amount of the ghost caused by the light beam indicated by the arrow L2. Such a configuration is not limited to the first embodiment, and may be applied to each embodiment described below.

Modification 2 of Embodiment 1
In the first embodiment, the half mirror is not formed on the second surface 62, but a half mirror (fourth half mirror) may be provided to be in contact with the second surface 62. The fourth half mirror is formed of a layer having the same or different configuration as the first half mirror 81 and the second half mirror 82. Such a configuration is not limited to the first embodiment, and may be applied to each embodiment described below.

Second Embodiment
FIG. 5 is an explanatory view of a light guide device 50 according to a second embodiment of the present invention. In addition, since the basic configuration of the present embodiment and the embodiment to be described later is the same as that of the first embodiment, the same reference numerals are given to the common portions and the description thereof will be omitted.

  In the first embodiment, the third surface 63 is parallel to the end surface 65 of the first light guide 60 and the end surface 75 of the second light guide 70, but as shown in FIG. The end face 65 of the first light guide 60 and the end face 75 of the second light guide 70 are inclined. In the present embodiment, the third surface 63 has a first boundary 631 with the first surface 61 (an end portion 611 of one side T 1 of the first surface 61 in the thickness direction T) a second boundary 632 with the second surface 62. It is inclined so as to be located on the end face 65 side from (the end 621 of one side T1 of the second face 62 in the thickness direction T). When configured in this manner, the light transmitted through the first half mirror 81 travels the image light L0 in the first light guide 60 by the second half mirror 82 of the third surface 63, as indicated by the arrow L2. It is reflected in the opposite direction to the direction of For this reason, the light transmitted through the first half mirror 81 is less likely to be incident on the eye E of the observer than in the first embodiment, so that the ghost is less likely to be recognized by the observer.

Third Embodiment
FIG. 6 is an explanatory view of a light guide device 50 according to a third embodiment of the present invention. As shown in FIG. 6, also in this embodiment, the third surface 63 is inclined with respect to the end surface 65 of the first light guide 60 and the end surface 75 of the second light guide 70. In the present embodiment, the third surface 63 is inclined such that the first boundary 631 with the first surface 61 is separated from the end surface 65 more than the second boundary 632 with the second surface 62. In such a configuration, the light transmitted through the first half mirror 81 is largely separated from the light reflected by the first half mirror 81 by the second half mirror 82 of the third surface 63, as shown by the arrow L2. It is reflected in the direction. For this reason, the light transmitted through the first half mirror 81 is less likely to be incident on the eye E of the observer than in the first embodiment, so that the ghost is less likely to be recognized by the observer.

Fourth Embodiment
FIG. 7 is an explanatory view of a light guide device 50 according to Embodiment 4 of the present invention. In the first, second, and third embodiments, the third surface 63 is a flat surface, but as shown in FIG. 7, the third surface 63 may be a curved surface. In the present embodiment, the third surface 63 has a central portion between the first boundary 631 with the first surface 61 and the second boundary 632 with the second surface 62 protruding from the first boundary 631 and the second boundary 632 It is a convex curved surface. When configured in this manner, light transmitted through the first half mirror 81 is dispersed and reflected by the third surface 63. Therefore, unlike the case where the third surface 63 is a flat surface, the light transmitted through the first half mirror 81 is difficult to enter the eye E of the observer regardless of the inclination of the third surface 63 and the like. It is hard to be recognized by the observer.

Fifth Embodiment
FIG. 8 is an explanatory view of a light guide device 50 according to Embodiment 5 of the present invention. As shown in FIG. 8, in the present embodiment, the third surface 63 has a central portion between the first boundary 631 with the first surface 61 and the second boundary 632 with the second surface 62. And the second boundary 632 is concave. When configured in this manner, light transmitted through the first half mirror 81 is dispersed and reflected by the third surface 63. Therefore, unlike the case where the third surface 63 is a flat surface, the light transmitted through the first half mirror 81 is difficult to enter the eye E of the observer regardless of the inclination of the third surface 63 and the like. It is hard to be recognized by the observer.

Sixth Embodiment
FIG. 9 is an explanatory view of a light guide device 50 according to a sixth embodiment of the present invention. As shown in FIG. 9, in the present embodiment, the first light guide 60 includes the adjacent first surface 61 and second surface 62 among the plurality of first surfaces 61 and the plurality of second surfaces 62. Between the end 612 of the other side T2 in the thickness direction T of the first surface 61 and the end 622 of the other side T2 of the second surface 62 in the third direction D An extending fourth surface 64 is provided. Further, a third half mirror 83 is formed on the fourth surface 64, and the third half mirror 83 is connected to the first half mirror 81. The third half mirror 83 is formed of a layer having the same or different configuration as the first half mirror 81 and the second half mirror 82.

  In such a configuration, the dimension of the second surface 62 in the second direction B can be shortened, so the extension distance of the third surface 63 can be shortened. Therefore, since the extension dimension of the first surface 61 on one side T1 in the thickness direction T can be lengthened, the amount of light reflected by the first half mirror 81 and emitted from the end surface 65 can be increased. it can. In the present embodiment, the fourth surface 64 is provided based on the first embodiment, but the fourth surface 64 may be provided based on the second to fifth embodiments.

Seventh Embodiment
FIG. 10 is an explanatory view of a light guide device 50 according to a seventh embodiment of the present invention. In the first to sixth embodiments, the positions of the plurality of first surfaces 61 (first half mirrors 81) in the thickness direction T are the same when using the end surface 65 as a reference, but as shown in FIG. When using 65 as a reference, the positions in the thickness direction T of the plurality of first surfaces 61 (first half mirrors 81) change along the arrangement direction of the plurality of first surfaces 61. More specifically, the first surface 61 provided on the other side X2 in the lateral direction X is closer to the end surface 65 than the first surface 61 provided on the one side X1 in the lateral direction X. Corresponding to the configuration, the dimension in the second direction B of the plurality of second surfaces 62 also changes along the arrangement direction of the plurality of first surfaces 61. More specifically, the second surface 62 provided on the other side X2 in the lateral direction X has a shorter dimension in the second direction B than the second surface 62 provided on the one side X1 in the lateral direction X. There is. As a result, the length of the third surface 63 also changes along the arrangement direction of the plurality of first surfaces 61. More specifically, the third surface 63 provided on the other side X2 in the lateral direction X is closer to the arrangement direction of the plurality of first surfaces 61 than the third surface 63 provided on the one side X1 in the lateral direction X The dimensions are shortened.

  Even in this configuration, the light transmitted through the first half mirror 81 is emitted in a direction different from that of the light reflected by the first half mirror 81 and does not enter the eye E of the observer, thereby suppressing the generation of ghosts. can do. In the present embodiment, the position of the first surface 61 is changed based on the first embodiment, but the position of the first surface 61 may be changed based on the second to sixth embodiments.

[Eighth embodiment]
FIG. 11 is an explanatory view of a light guide device 50 according to an eighth embodiment of the present invention, and FIG. 11 is a perspective view (a) and a front view of the state in which the first light guide 60 is not shown. b) is shown. FIG. 12 is an explanatory view showing the first surface 61 and the like of the light guide device 50 shown in FIG. 11 in an enlarged manner.

  As shown in FIGS. 11 and 12, in the light guide device 50 of the present embodiment, the plurality of first surfaces 61 are concave surfaces which are recessed toward the second light guide 70. In the present embodiment, each of the plurality of first surfaces 61 is a concave surface that extends while being curved in a direction (vertical direction Y) orthogonal to the lateral direction X. Accordingly, the plurality of first surfaces 61 are also recessed in the direction (lateral direction X) in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged. In the present embodiment, the second surface 62 also extends along the first surface 61 while curving in the vertical direction Y. The third surface 63 also extends along the first surface 61 and the second surface 62 while curving in the vertical direction Y. Therefore, the entire light guiding device 50 extends while curving in the vertical direction Y. Therefore, even if the first surface 61 is curved, the thickness of the light guiding device 50 (the thickness in the front-rear direction Z / the dimension in the direction in which the first light guiding member 60 and the second light guiding member 70 overlap) Can be suppressed.

  In the present embodiment, the curvatures of the plurality of first surfaces 61 are equal. However, the widths of the plurality of first surfaces 61 change along the lateral direction X.

  According to the light guide device 50 having such a configuration, it is possible to exert the power to condense the light incident on the first surface 61 in the vertical direction Y. Therefore, the light incident on the light guide device 50 can be used as an observer's eye. It can be made to inject efficiently.

[Embodiment 9]
FIG. 13 is an explanatory view of a light guide device 50 according to Embodiment 9 of the present invention, and FIG. 13 is a perspective view (a) and a front view of the state in which the first light guide 60 is not shown. b) is shown. FIG. 14 is an explanatory view showing the first surface 61 and the like of the light guide device 50 shown in FIG. 13 in an enlarged manner. FIG. 15 is an explanatory view showing the configuration of the third surface 63 etc. of the light guide device 50 shown in FIG. 13. FIG. 15 is a front view (a) showing the width of the third surface 63, A1-A1 '. A cross-sectional view (b) and a B1-B1 'cross-sectional view are shown. In the front view (a) of FIG. 13, the third surface 63 is hatched.

  As shown in FIG. 13, FIG. 14 and FIG. 15, in the light guide device 50 of this embodiment as well, as in the eighth embodiment, a plurality of first surfaces 61 are concave surfaces respectively recessed toward the second light guide 70. It has become. In the present embodiment, each of the plurality of first surfaces 61 is a concave surface that extends while being curved in a direction (vertical direction Y) orthogonal to the lateral direction X. Accordingly, the plurality of first surfaces 61 are also recessed in the direction (lateral direction X) in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged. In the present embodiment, the second surface 62 also extends along the first surface 61 while curving in the vertical direction Y. The third surface 63 also extends along the first surface 61 and the second surface 62 while curving in the vertical direction Y.

  Here, in the plurality of first surfaces 61, the curvature of the first surface 61 decreases from the right side X1 to the left side X2 in the lateral direction X. That is, when the curvatures of the first surface 61 are C1, C2, and C3, the magnitudes of the curvatures are in the order of the curvature C1, the curvature C2, and the curvature C3. The second surface 62 and the third surface 63 are curved along the adjacent first surfaces 61.

  In the present embodiment, between the first surfaces 61 having different curvatures, the second surfaces 62 are wide at both ends in the vertical direction Y and narrow at the central portion. Corresponding to the shape, the third surface 63 is also wide at both ends in the vertical direction Y and narrow at the central portion.

Tenth Embodiment
16 is an explanatory view showing the configuration of the third surface 63 etc. of the light guide device 50 according to Embodiment 10 of the present invention, and FIG. 16 is a front view (a) showing the width of the third surface 63, A1-A1 'sectional view (b) and B1-B1' sectional view are shown. In the front view (a) of FIG. 16, the third surface 63 is hatched. As shown in FIG. 16, in the light guide device 50 according to the present embodiment as well, as in the eighth and ninth embodiments, the plurality of first surfaces 61 are each a concave surface recessed toward the second light guide 70. . In the present embodiment, each of the plurality of first surfaces 61 is a concave surface that extends while being curved in a direction (vertical direction Y) orthogonal to the lateral direction X. Accordingly, the plurality of first surfaces 61 are also recessed in the direction (lateral direction X) in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged. In the present embodiment, the second surface 62 also extends along the first surface 61 while curving in the vertical direction Y. The third surface 63 also extends along the first surface 61 and the second surface 62 while curving in the vertical direction Y.

  Here, the curvature of each of the plurality of first surfaces 61 is such that the curvature of the first surface 61 is larger from the right side X1 to the left side X2 in the lateral direction X. That is, assuming that the curvatures of the first surface 61 are C1, C2, and C3, the magnitudes of the curvatures are in the order of the curvature C3, the curvature C2, and the curvature C1. The second surface 62 and the third surface 63 are curved along the adjacent first surfaces 61.

  In the present embodiment, the second surface 62 has a narrow width at both ends in the vertical direction Y and a wide central portion between the first surfaces 61 having different curvatures. Corresponding to the shape, the third surface 63 is also narrow at both ends in the vertical direction Y and wide at the central portion. The aspects described in the eighth, ninth, and tenth embodiments can be applied to any of the embodiments of the present invention in addition to the first embodiment of the present invention.

[Embodiment 11]
FIG. 17 is an explanatory diagram of a light guide device 50 according to Embodiment 11 of the present invention. As shown in FIG. 17, in the eighth to tenth embodiments, a concave surface in which the plurality of first surfaces 61 are recessed in the direction (lateral direction X) in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged. To extend in a direction (vertical direction Y) orthogonal to the lateral direction X, as shown in FIG. 17, the plurality of first surfaces 61 are respectively a plurality of first surfaces 61 as shown in FIG. And the aspect extended while curving in the direction (lateral direction X) by which the several 2nd surface 62 was arranged may be sufficient.

[Embodiment 12]
FIG. 18 is an explanatory view of a light guide device 50 according to Embodiment 12 of the present invention. As shown in FIG. 18, even in the aspect in which the entire light guiding device 50 extends while curving in the direction (lateral direction X) in which the plurality of first surfaces 61 and the plurality of second surfaces 62 are arranged. Good.

[Embodiment 13]
FIG. 19 is an explanatory diagram of a display device 100 according to Embodiment 13 of the present invention. In the first to seventh embodiments, the image light L0 is made to travel in the lateral direction X in the light guide device 50, but in the present embodiment, the image light L0 in the vertical direction Y in the light guide device 50 as shown in FIG. The present invention may be applied when advancing from the upper side Y1 to the lower side Y2 and emitting the light to the eye E of the observer.

[Other embodiments]
In the above embodiment, the third surface 63 is between the end 611 of the one side T1 in the thickness direction T of the first surface 61 and the end 621 of the one side T1 of the second surface 62 in the thickness direction T. Although the third surface 63 is provided, the third surface 63 includes the end 612 of the other side T2 in the thickness direction T of the first surface 61 and the end 622 of the other side T2 of the second surface 62 in the thickness direction T. The aspect provided between may be sufficient. The third surface 63 is between the end 611 of the one side T1 in the thickness direction T of the first surface 61 and the end 621 of the one side T1 of the second surface 62 in the thickness direction T, and a third A surface 63 is provided both between the end 612 of the other side T2 in the thickness direction T of the first surface 61 and the end 622 of the other side T2 of the second surface 62 in the thickness direction T. It may be an aspect.

  In the said embodiment, although the 2nd light guide 70 was a translucent resin member, the 2nd light guide 70 may be an air layer.

DESCRIPTION OF SYMBOLS 10, 10a, 10b ... Display part, 20 ... Image light emission apparatus, 21 ... Display panel, 30 ... Light guide optical system, 31, 32, 33, 34 ... Lens, 35 ... Mirror, 50 ... Light guide apparatus, 50a ... Light guide device for the right eye, 50b: light guide device for the left eye, 51: antireflection layer, 60: first light guide, 61: first surface, 62: second surface, 63: third surface, 64: Fourth surface, 65, 75 ... end face, 70 ... second light guide, 81 ... first half mirror, 82 ... second half mirror, 83 ... third half mirror, 90 ... frame, 91 ... front portion 92a, 92b: Temple, 100: Display device, 611, 621: One end, 612, 622: Other end, 631: First boundary, 632: Second boundary, A: First direction, B: First 2 directions, T: thickness direction, D: third direction, E: eye, L0, L0a, L0b: image light.

Claims (21)

A plurality of first surfaces, each extending along a first direction, and a second direction in which each crosses the first direction between adjacent first surfaces of the plurality of first surfaces A first light guide including a plurality of second surfaces extending in one direction in the thickness direction and an end surface on the other side in the thickness direction;
A plurality of first half mirrors, each in contact with the plurality of first surfaces;
The plurality of first half mirrors, and a second light guide in contact with the plurality of second surfaces;
Have
The first light guide includes two of the plurality of first surfaces and two of the plurality of second surfaces, which are located on both sides of the second surface between adjacent first and second surfaces. A plurality of third surfaces, each overlapping the second surface in a direction along a third direction in which the one surfaces do not overlap with each other,
Each of the plurality of third surfaces extends in a direction different from the first direction. In the light guide device according to claim 1,
A light guide device, wherein a refractive index of the first light guide and a refractive index of the second light guide are different. In the light guide device according to claim 1 or 2,
A plurality of second half mirrors, each of which is in contact with the plurality of third surfaces, are provided between the first light guide and the second light guide. In the light guide device according to claim 3,
A light guide device characterized in that the reflectance of the first half mirror and the reflectance of the second half mirror are equal. In the light guide device according to claim 3,
A light guide device characterized in that the reflectance of the first half mirror and the reflectance of the second half mirror are different. The light guide device according to any one of claims 1 to 5,
Each of the plurality of third surfaces is one of the plurality of first surfaces and the plurality of second surfaces, between the adjacent first surfaces and the second surface, in one of the thickness directions of the first surfaces. A light guide device, characterized in that it is provided between an end on the side and an end on one side in the thickness direction of the second surface. In the light guide device according to claim 6,
The thickness of the first surface of the first light guide may be between the adjacent first surface and the second surface among the plurality of first surfaces and the plurality of second surfaces. A fourth surface extending in the third direction is provided between each of the other end of the direction and the other end of the second surface in the thickness direction. Light guiding device. In the light guide device according to claim 7,
A plurality of third half mirrors, each in contact with the plurality of fourth surfaces, are provided between the first light guide and the second light guide. The light guide device according to any one of claims 1 to 8.
A light guide device characterized in that each of the plurality of third surfaces is parallel to a direction in which the plurality of first surfaces and the plurality of second surfaces are arranged. The light guide device according to any one of claims 1 to 8.
A light guide device characterized in that each of the plurality of third surfaces is a slope inclined with respect to a direction in which the plurality of first surfaces and the plurality of second surfaces are arranged. The light guide device according to any one of claims 1 to 8.
Each of the plurality of third surfaces is a convex curved surface in which a central portion between the first boundary with the first surface and the second boundary with the second surface protrudes from the first boundary and the second boundary. A light guide device according to claim 1, wherein the central portion is a concave surface recessed from the first boundary and the second boundary. The light guide device according to any one of claims 1 to 11.
The light guide device according to claim 3, wherein the third direction is a direction in which a light beam incident on the first half mirror travels through the first half mirror and the second surface. The light guide device according to any one of claims 1 to 12.
A position of the plurality of first surfaces in the thickness direction is changed along the arrangement direction of the plurality of first surfaces with reference to the end face. The light guide device according to any one of claims 1 to 13.
A plurality of fourth half mirrors, each in contact with the plurality of second surfaces, are provided between the first light guide and the second light guide. The light guide device according to any one of claims 1 to 14,
Each of the plurality of first surfaces is a concave surface which is recessed toward the second light guide. In the light guide device according to claim 15,
The plurality of first surfaces and the plurality of second surfaces are formed such that the plurality of first surfaces are concave surfaces which are recessed in the direction in which the plurality of first surfaces and the plurality of second surfaces are arranged. A light guide device extending while curving in a direction orthogonal to the arranged direction. In the light guide device according to claim 16,
The light guide device according to claim 1, wherein the second surface is curved along the first surface. The light guide device according to any one of claims 15 to 18.
A light guide device characterized in that a curvature of each of the plurality of first surfaces changes along a direction in which the plurality of first surfaces and the plurality of second surfaces are arranged. A light guiding device according to any one of claims 1 to 18,
An image light emitting device for emitting image light;
The display device according to claim 1, wherein the image light enters each of the plurality of first surfaces in the first light guide from the third direction. In the display device according to claim 19,
The display device characterized in that the image light enters the first light guiding body from the end face of the first light guiding body. The display device according to claim 19 or 20
The optical path from the image light emitting device toward the first light guide includes a light guiding optical system for guiding the image light emitted from the image light emitting device to the first light guide. Characteristic display device.