WO2019021350A1

WO2019021350A1 - Head-mounted display device

Info

Publication number: WO2019021350A1
Application number: PCT/JP2017/026729
Authority: WO
Inventors: 辰巳炭竃; 潤岩田; 貴拓伊達; 増田　麻言; 伸弘白井
Original assignee: サン電子株式会社
Priority date: 2017-07-24
Filing date: 2017-07-24
Publication date: 2019-01-31
Also published as: JPWO2019021350A1

Abstract

A head-mounted display device comprises: a frame attachable to a user's head; a light guide plate provided on the frame at a position facing a part of user's face including the eyes and transmitting incident light via total reflection between the inner sides of two principal surfaces, thereby outputting the light toward the eyes; a projection device disposed at a position near the outer edge of the light guide plate and projecting the light forming an image toward the inside of the light guide plate; and a protective member facing at least one of the two principal surfaces in the light guide plate, the protective member being arranged between a center portion including a range facing the eyes in the light guide plate, and an outer portion outside the center portion, which includes a portion where the projection device is provided. An interface between the range facing the protective member in the principal surface and the outside of the principal surface has optical reflection properties that allow total reflection.

Description

Head-mounted display

The technology disclosed by the present specification relates to a head mounted display used by being mounted on the head of a user.

For example, Japanese Patent Application Laid-Open No. 2010-48998 (hereinafter referred to as Patent Document 1) discloses a head-mounted display used by being attached to the head of a user. This head-mounted display device includes a frame that can be attached to the user's head, and an image forming device provided on the frame. The image forming apparatus includes a light guide plate, a projection device, and a housing. The light guide plate is disposed at a position facing a part of the face including the user's eyes, and the light incident on the inside is guided by being totally reflected by the inner surfaces of the two main surfaces, and then toward the eyes It is a board for emitting light. A projection apparatus is an apparatus which irradiates the light which forms an image toward the inside of a light-guide plate. The housing covers the projection device and is disposed on an outer portion of the main surface on the side facing the user's face. By providing the housing, adhesion of dust, moisture, and the like attached to the light guide plate to the projection apparatus is prevented.

In the technique of Patent Document 1, there are cases where the housing and the light guide plate are in close contact with each other for dustproofness and waterproofness of the projection device. In that case, the light reflection performance on the main surface of the light guide plate, which should be realized by the difference in refractive index between the light guide plate and the air, because a layer of air is not formed between the light guide plate and the housing. There may be situations where you As a result, a portion where light is not totally reflected is formed on the main surface of the light guide plate, and there is a possibility that the light for forming an image on the user's eyes may not be appropriately irradiated.

The present specification discloses a technique that can suppress adhesion of dust, moisture, and the like attached to the light guide plate to the projection apparatus, and can appropriately irradiate light for forming an image to the user's eye.

The head mounted display disclosed by the present specification is provided with a frame that can be attached to the head of the user, the frame, and a position facing a part of the face including the eye of the user A light guide plate for guiding light incident on the inside by total reflection on the inner surfaces of the two main surfaces, and a position near the outer peripheral edge of the light guide plate for emitting the light toward the eye And a protective member disposed opposite to at least one of the two main surfaces of the light guide plate, and a projection device for emitting light forming an image toward the inside of the light guide plate. Between the central portion of the light guide plate that includes the area facing the eye and the outer portion that is outside the central portion and that includes the portion on which the projection device is provided. And the above-mentioned protection member. The interface between the area facing the protective member and the outside of the main surface of the light guide plate has light reflectivity that totally reflects light.

According to this configuration, the provision of the protective member can prevent dust and moisture adhering to the central portion of the light guide plate from adhering to the projection device. Furthermore, according to this configuration, since the interface between the area facing the protective member and the outside of the main surface of the light guide plate has light reflectivity that totally reflects light, the light guide plate and the protective member are disposed so as to face each other. Even in this case, the formation of a portion where light is not totally reflected is suppressed on the main surface of the light guide plate. As a result, since the light is appropriately totally reflected on the inner surface of the main surface of the light guide plate, it is possible to appropriately irradiate the light forming the image on the user's eyes. Therefore, according to the above configuration, it is possible to suppress adhesion of dust, moisture and the like attached to the light guide plate to the projection device, and it is possible to appropriately irradiate the light forming the image to the user's eyes.

The head-mounted display device is an interposed member interposed between the light guide plate and the protective member, and further includes the interposed member that causes light to be totally reflected at the interface. It is also good.

According to this configuration, by providing the intervening member, it is possible to exhibit light reflectivity that totally reflects light at the interface between the area facing the protective member and the outside on the main surface of the light guide plate. Even when the light guide plate and the protective member have a configuration in which light reflectivity can not be exhibited, the light reflectivity can be ensured by interposing the intervening member.

The interposition member is provided in close contact with the at least one main surface of the light guide plate, and at least the surface on the side closely in contact with the light guide plate is light reflective so as to totally reflect light. It may be a member having one.

The interposing member may be a member provided in close contact with the at least one main surface of the light guide plate and having the same light refractive index as air.

The protective member is made of an elastic material, and is pressed toward the at least one main surface of the light guide plate to seal a gap between the light guide plate and the protective member. It is also good.

According to this configuration, by providing the protective member, the central portion and the outer portion of the light guide plate are partitioned without a gap. Thereby, the dust and moisture attached to the central portion of the light guide plate can be more appropriately suppressed from adhering to the projection device.

The protective member may be disposed to face each of the two main surfaces of the light guide plate, and may be provided to sandwich the light guide plate.

According to this configuration, even if, for example, the projection device is provided so as to straddle both of the two main surfaces of the light guide plate, it is appropriate that dust and moisture attached to the central portion of the light guide plate adhere to the projection device. It can be suppressed to

1 shows the appearance of a head mounted display. 1 schematically shows an internal configuration of a head-mounted display device.

(First embodiment)
(Configuration of Head Mounted Display 10; FIG. 1, FIG. 2)
The head-mounted display device 10 illustrated in FIG. 1 is a display device (so-called head mounted display) used by being attached to the head of a user. Hereinafter, in the present specification, the head mounted display 10 is referred to as a “display 10”. As shown in FIG. 1, the display device 10 includes a frame 12, a right light guide plate 20R, a left light guide plate 20L, a right projection device 30R, a left projection device 30L, a right protection member 40R, and a left protection member 40L. And.

The frame 12 shown in FIG. 1 is an eyeglass frame-like member. The user can wear the display device 10 on the head by wearing the frame 12 so as to wear glasses. In another example, the frame 12 may be a headband-like member, a helmet-like member, or any other frame that can be worn on the head.

The right light guide plate 20R is a translucent substrate. The right light guide plate 20R is formed of, for example, glass. In another example, the right light guide plate 20R may be formed of a light transmissive resin material or the like. When the user wears the display device 10 on the head, the right light guide plate 20R is disposed at a position facing the range including the right eye (see RE in FIG. 2) of the user's face.

As shown in FIG. 2, the right light guide plate 20R has a first main surface 22R which is a main surface facing the user's face (that is, the right eye RE) and a main surface opposite to the first main surface 22R ( That is, it has the 2nd main surface 24R which is a field far from a face). The right light guide plate 20R guides the light incident inside from the right projection device 30R by totally reflecting the inner surface of the first main surface 22R and the inner surface of the second main surface 24R, and then transmits the light to the right eye RE. Make it emit towards (see the broken arrow in FIG. 2). The path through which the light emitted from the right projector 30R (ie, the light representing the image for the right eye) passes will be described in detail later.

A plurality of half mirror members 26R are provided in the right light guide plate 20R. In the example of FIG. 2, three half mirror members 26R are provided inside the right light guide plate 20R, but in the other example, the number of half mirror members 26R is two or more, and any number may be used. It may be. The plurality of half mirror members 26R are arranged side by side along a direction from the side where the right projector 30R is provided (i.e., the outside of the face) toward the center side of the face of the user. As shown in FIG. 2, the plurality of half mirror members 26 </ b> R are disposed in a range facing the user's right eye RE.

Each of the plurality of half mirror members 26R is a member that reflects a part of the light guided in the right light guide plate 20R, transmits the other part, and emits the reflected light toward the right eye RE It is. Each half mirror member 26R is a structure in which dielectric films such as SiO 2 and TiO 2 are laminated. The half mirror members 26R are disposed to form a predetermined angle with respect to the first major surface 22R of the right light guide plate 20R, and are disposed in parallel at equal intervals.

As shown to FIG. 1, FIG. 2, the right projector 30R is arrange | positioned in the outer-periphery vicinity of the right light-guide plate 20R. The right projector 30R may be rephrased as being disposed at a position on the outside of the user's face (that is, a position near the right ear) in the right light guide plate 20R. The right projection device 30R is a projection device for emitting light that forms a display image for the right eye (hereinafter, referred to as “image for right eye”) toward the inside of the right light guide plate 20R. Here, the image for the right eye is an image showing a portion corresponding to the view range of the right eye in one target image to be visually recognized by the user.

The right projector 30R includes a light source and a prism (not shown). The light source is a light source for emitting light representing the above-described right-eye image. The light source includes a light emitting diode (LED) panel, a liquid crystal on silicon (LCOS) panel, and an optical element (e.g., a lens). The light source can emit light in various modes in accordance with an instruction of a control unit (not shown) mounted on the frame 12. The prism is a light guiding optical element for introducing the light emitted from the light source into the right light guide plate 20R after passing the light.

As shown in FIGS. 1 and 2, the right protecting member 40R is a cover member for covering the right projector 30R. In the present embodiment, the right protective member 40R covers the right end portion of the right light guide plate 20R, the right projection device 30R, a part of the right rim portion of the frame 12, and the right temple portion of the frame 12. As shown in FIG. 2, the right protecting member 40R sandwiches the right end portion (that is, the portion near the outside of the face) of the right light guide plate 20R from both sides of the first main surface 22R and the second main surface 24R. In the present embodiment, the right protective member 40R is formed of a resin material having elasticity, and is opposed to the end 42R facing the first main surface 22R of the right protective member 40R and the second main surface 24R. The end portions 44R are provided so as to be pressed onto the first main surface 22R and the second main surface 24R of the right light guide plate 20R, respectively. That is, the right protecting member 40R is attached so as to sandwich the right light guide plate 20R from both sides, and the gap between the right protecting member 40R and the right light guide plate 20R is sealed.

As shown in FIG. 2, a reflection layer 52R is formed in a range facing the end 42R of the right protection member 40R in the outer surface of the first major surface 22R of the right light guide plate 20R. Similarly, a reflection layer 54R is formed in a range facing the end 44R of the right protection member 40R in the outer surface of the second major surface 24R of the right light guide plate 20R. In the present embodiment, the

reflective layers

52R and 54R are metal layers formed by vapor deposition of a metal material (for example, aluminum, titanium, chromium, stainless steel, gold, silver or the like). The reflection layer 52R is a mirror that reflects both surfaces to the interface between the area facing the end 42R of the right protection member 40R and the outside, of the first main surface 22R of the right light guide plate 20R. It is possible to demonstrate the nature. Similarly, both surfaces of the reflective layer 54R are mirror surfaces, and light is totally reflected at the interface between the area facing the end 44R of the right protective member 40R and the outside in the second main surface 24R of the right light guide plate 20R. Light reflectivity can be exhibited. That is, the

reflective layers

52R and 54R may be rephrased to be mirror coat layers. By providing the

reflective layers

52R and 54R, light can be totally reflected also in the range facing the

end portions

42R and 44R of the inner surface of the right light guide plate 20R. In another example, the

reflective layers

52R and 54R may be a mirror coat layer formed by applying a metal material, or a mirror coat layer formed by plating.

Subsequently, with reference to FIG. 2, a path through which light emitted from the right projector 30R (that is, light representing an image for the right eye) passes in the display device 10 of the present embodiment will be described. In FIG. 2, the light path is schematically shown by a dashed arrow. The light path shown in FIG. 2 is merely an example, and the present invention is not necessarily limited to this. As shown in FIG. 2, light incident from the right projector 30R into the right light guide plate 20R is totally reflected at the inner surface (point P1 in the drawing) of the first major surface 22R. As described above, in the present embodiment, the reflective layer 52R is formed on the outer surface of the point P1 of the first major surface 22R. As described above, since the surface of the reflective layer 52R that is in close contact with the first major surface 22R is a mirror surface, light can be totally reflected. Therefore, as shown in FIG. 2, even if the configuration in which the outer surface of the point P1 of the first main surface 22R faces the end 42R is employed, the inner surface of the first main surface 22R receives light at the point P1. It can be totally reflected.

The light after being totally reflected at the point P1 is subsequently totally reflected at a point P2 on the inner surface of the second major surface 24R. As described above, in the present embodiment, the reflective layer 54R is formed on the outer surface of the point P2 of the second major surface 24R. As described above, since the surface of the reflective layer 54R that is in close contact with the second major surface 24R is a mirror surface, light can be totally reflected. Therefore, as shown in FIG. 2, even though the configuration in which the outer surface of the point P2 of the second main surface 24R faces the end 44R is employed, the inner surface of the second main surface 24R emits light at the point P2. It can be totally reflected.

The light after being totally reflected at the point P2 is subsequently totally reflected at a point P3 on the inner surface of the first major surface 22R. As shown in FIG. 2, the right protecting member 40R does not face the outer surface of the point P3. That is, the outer surface of the point P3 faces air. Therefore, the inner surface of the first major surface 22R can totally reflect light at the point P3.

The light after being totally reflected at the point P3 is then totally reflected by the inner surface of the first main surface 22R and the inner surface of the second main surface 24R while being directed from the outside to the inside of the face (ie from the right ear of the user The light is guided along the direction toward the right eye RE. The light guided in the right light guide plate 20R is partially reflected by the plurality of half mirror members 26R and partially transmitted. The light reflected by each half mirror member 26R is emitted toward the right eye RE. As a result, an image for the right eye is formed on the retina of the right eye RE. Thereby, the right eye RE of the user can visually recognize the image for the right eye.

The configurations and the light paths of the right light guide plate 20R, the right projection device 30R, and the right protection member 40R have been described above with reference to FIG. The configuration of the left light guide plate 20L, the left projection device 30L, and the left protection member 40L and the light path are also the same as the right light guide plate 20R, the right projection device 30R, and the right protection member 40R, except that the right and left are opposite. It is similar. Light is incident on the left light guiding plate 20L from the left projector 30L through the same path as described above, and an image for the left eye is formed on the retina of the user's left eye, and the user's left eye views the image for the left eye can do. The user can view one target image by viewing the right-eye image with the right eye RE and viewing the left-eye image with the left eye. In the following, when the right light guide plate 20R and the left light guide plate 20L are referred to without distinction, they are simply referred to as the “light guide plate 20” and when the right projection device 30R and the left projection device 30L are referred to without distinction. If the right protective member 40R and the left protective member 40L are referred to without distinction, they may be simply referred to as the "protective member 40". Even when a part of each member (for example, the first main surface 22R, the second main surface 24R, the

end portions

42R, 44R, etc.) is called without distinction between right and left, it is simply referred to as "first main surface 22", "second main It may be called by omitting the distinction between "R" and "L" as in the plane 24 "and" ends 42, 44 ".

Heretofore, the configuration of the display device 10 of the present embodiment and the path of light emitted from the projection device 30 have been described. The display device 10 of the present embodiment has a protective member 40 that covers the projection device 30 (see FIGS. 1 and 2). The protective member 40 sandwiches a portion close to the outer side of the light guide plate 20 from both sides on the first major surface 22 side and the second major surface 24 side. Then, the protection member 40 is provided such that the end portions 42 and 44 are pressed against the first main surface 22 and the second main surface 24 and the gap between the light guide plate 20 is sealed. Therefore, in the present embodiment, the protective member 40 can appropriately prevent dust and moisture adhering to the central portion of the light guide plate 20 from adhering to the projection device 30.

Furthermore, in the present embodiment, the reflective layer 52R is formed on the outer surface of the first main surface 22 of the light guide plate 20, and the reflective layer 54R is formed on the outer surface of the second main surface 24. Thereby, the interface between the area facing the end portions 42 and 44 of the first main surface 22 and the second main surface 24 of the light guide plate 20 and the outside exhibits light reflectivity in which light is totally reflected. Can. Therefore, even if the light guide plate 20 and the protection member 40 are arranged to face each other, it is suppressed that a portion where light is not totally reflected is formed on the inner surface of the first main surface 22 and the inner surface of the second main surface 24. Be done. As a result, light is appropriately totally reflected on the inner surface of the first main surface 22 and the inner surface of the second main surface 24 of the light guide plate 20, so that the target image for the user's eye (that is, the image for the right eye and the left eye) Light to form an image) can be appropriately emitted. Therefore, according to the display device 10 of the present embodiment, adhesion of dust, moisture, and the like attached to the light guide plate 20 to the projection device 30 can be suppressed, and the light for forming an image is appropriately irradiated to the user's eyes. be able to.

Further, in the present embodiment, the reflection layers 52 and 54 in close contact with the light guide plate 20 are provided on the outer surface of the first main surface 22 and the outer surface of the second main surface 24 of the light guide plate 20. Therefore, even if the light guide plate 20 and the protective member 40 can not exhibit light reflectivity by themselves, by providing the reflective layers 52 and 54, light reflectivity at the interface between the light guide plate 20 and the outside can be obtained. Can be secured.

The reflective layers 52 and 54 of the present embodiment are an example of the “intervening member”.

Second Embodiment
The points different from the first embodiment will be mainly described. In the present embodiment, the reflection layers 52R and 54R in FIG. 2 are sheet-like reflection materials having light reflection performance. In the present embodiment, the reflective layer 52R is attached to the outer surface of the first main surface 22R, and the reflective layer 54R is attached to the outer surface of the second main surface 24R. In the present embodiment, at least the surface on the side facing the right light guide plate 20R of the

reflective layers

52R and 54R may have light reflectivity. In another example, the

reflective layers

52R and 54R may be attached to the

end portions

42R and 44R, respectively. The display device 10 of this modification can also exhibit the same function and effect as the display device 10 of the first embodiment.

Third Embodiment
The points different from the first embodiment will be mainly described. In the present embodiment, the

reflective layers

52R and 54R in FIG. 2 are layers of members having the same light refractive index (about 1.0) as air. The member having the same light refractive index as air may be any member as long as it has a light refractive index of about 1. In this case, the light reflection performance at points P1 and P2 in FIG. 2 is the same as the light reflection performance at point P3. Therefore, the display device 10 of the present modification can exhibit the same function and effect as the display device 10 of the first embodiment.

Fourth Embodiment
The points different from the first embodiment will be mainly described. In the present embodiment, the

reflective layers

52R and 54R of FIG. 2 are omitted. That is, in the present embodiment, the "intervening member" may be omitted. And the surface which opposes the right light-guide plate 20R among the

edge parts

42R and 44R of the right protection member 40R is formed with the member which can exhibit light reflectivity. That is, in the present embodiment, at least a part of the protective member 40R itself is formed of a member capable of exhibiting light reflectivity. In the present embodiment, the

end portions

42R, 44R are directly pressed against the right light guide plate 20R. Generally speaking, the interface between the area facing the protective member and the outside of the main surface of the light guide plate may have light reflectivity that totally reflects light. The display device 10 of this modification can also exhibit the same function and effect as the display device 10 of the first embodiment.

As mentioned above, although an Example was described in detail, these are only examples and do not limit the range of a claim. The art set forth in the claims includes various variations and modifications of the specific examples illustrated above. For example, the following modifications may be employed.

(Modification 1) In each of the above embodiments, as shown in FIG. 2, the projection device 30 is disposed in the vicinity of the outer peripheral edge of the light guide plate 20. The arrangement position of the projection device 30 is not limited to this, and may be provided at any position as long as light can be introduced into the light guide plate 20. Therefore, for example, the projection device 30 may be disposed at a position near the outer peripheral edge of the first major surface 22 of the light guide plate 20. In another example, the projection device 30 may be disposed at a position near the outer peripheral edge of the second major surface 24 of the light guide plate 20. Further, in still another example, the projection device 30 may be disposed so as to straddle the first major surface 22 and the second major surface 24.

(Modification 2) In each of the above-described embodiments, the protective member 40 sandwiches a portion close to the outside of the light guide plate 20 from both sides of the first main surface 22 side and the second main surface 24 side. The invention is not limited to this, and the protective member 40 may be disposed in close contact with one of the first main surface 22 side and the second main surface 24 side of the light guide plate 20. For example, when the projection device 30 is provided on the first main surface 22 side, the protection member 40 may be disposed so as to be in close contact with only the first main surface 22.

(Modification 3) In each of the above-described embodiments, the protective member 40 is formed of an elastic material, and the end portions 42 and 44 are pressed against the first major surface 22 and the second major surface 24 to conduct the conduction. A gap between the light plate 20 and the light plate 20 is sealed. Not limited to this, the protective member 40 may be formed of an inelastic member. Also in this case, the end portions 42 and 44 may be provided so as to be in close contact with the first major surface 22 and the second major surface 24. Also by the protective member 40 of this modification, adhesion of dust and the like attached to the central portion of the light guide plate 20 to the projection device 30 can be suppressed.

(Modification 4) In each of the above-described embodiments, the display device 10 includes the image forming apparatus on the right (ie, the right light guide plate 20R, the right projection device 30R and the right protective member 40R) and the image forming apparatus on the left (ie, Both the left light guide plate 20L, the left projection device 30L and the left protection member 40L are provided. Not limited to this, the display device may include only one of the image forming apparatus on the right side and the image forming apparatus on the left side.

(Modification 5) In each of the above-described embodiments, the right projector 30R is disposed at a position on the outer side of the user's face (that is, a position near the right ear) in the right light guide plate 20R. Of the left light guide plate 20L, that is, at a position near the user's face (that is, a position near the left ear). The invention is not limited thereto, and the right projector 30R may be disposed in the upper part of the right light guide plate 20R (ie, the end closer to the user's eyebrow). Similarly, the left projector 30L may be disposed on the upper portion of the left light guide plate 20L (that is, the end closer to the user's side). In this modification, the plurality of half mirror members 26R inside the right light guide plate 20R are arranged along a direction from the side where the right projection device 30R is provided (that is, the upper side of the face) to the lower side. It may be done. The same may be applied to a plurality of half mirror members inside the left light guide plate 20L.

The technical elements described in the present specification or the drawings exhibit technical usefulness singly or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques illustrated in the present specification or the drawings simultaneously achieve a plurality of purposes, and achieving one of the purposes itself has technical utility.

Claims

A head mounted display,
A frame that can be worn on the user's head,
After being provided in the frame and disposed at a position facing a part of the face including the eyes of the user, the light incident on the inside is guided by being totally reflected by the inner surfaces of the two main surfaces, A light guide plate for emitting toward the eye;
A projection device disposed at a position near the outer peripheral edge of the light guide plate, and emitting light forming an image toward the inside of the light guide plate;
A protective member disposed opposite to at least one of the two main surfaces of the light guide plate, the center portion including a range of the light guide plate facing the eye, and the center The protective member disposed between the outer portion of the portion and the outer portion including the portion where the projection device is provided;
The interface between the area facing the protective member and the outside of the main surface of the light guide plate has light reflectivity that totally reflects light,
Head-mounted display.
The interposition member interposed between the light guide plate and the protection member, further comprising the interposition member that exerts light reflectivity to totally reflect light at the interface.
The head mounted display according to claim 1.
The interposition member is provided in close contact with the at least one main surface of the light guide plate, and at least the surface on the side closely in contact with the light guide plate is light reflective so as to totally reflect light. A member that has
The head mounted display according to claim 2.
The interposed member is a member provided in close contact with the at least one main surface of the light guide plate and having the same light refractive index as air.
The head mounted display according to claim 2.
The protective member is made of an elastic material, and seals the gap between the light guide plate and the protective member by being pressed toward the at least one main surface of the light guide plate.
The head mounted display according to any one of claims 1 to 4.
The protection member is disposed to face each of the two main surfaces of the light guide plate, and provided so as to sandwich the light guide plate.
The head mounted display according to any one of claims 1 to 5.