JP2013061594A - Virtual image display device and method for manufacturing virtual image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a virtual image display device and a method for manufacturing the virtual image display device, in which see-through observation in a good state can be achieved while the occurrence of deterioration in an optical element for forming a virtual image is suppressed.SOLUTION: A half mirror layer 28 is covered with a hard coat layer CC1. When a light-transmitting member 23 as a transparent member to transmit external light without distortion is bonded to the half mirror layer 28, the hard coat layer CC1 is present in the bonding portion, which can avoid degradation in optical characteristics of the half mirror layer 28 as a semi-transmissive reflection film due to influences of an adhesive containing a solvent or the like. As the half mirror layer 28 as a semi-transmissive reflection film is reliably protected, the state of reflecting image light as well as transmitting external light, which is an optical function of the half mirror layer 28, is appropriately maintained and see-through observation in a good state can be achieved.

Description

  The present invention relates to a virtual image display device such as a head mounted display that is used by being mounted on a head.

  2. Description of the Related Art In recent years, various types of virtual image display devices capable of forming and observing virtual images such as a head-mounted display have been proposed that guide image light from a display element to an observer's pupil using a light guide plate.

  In such a virtual image display device, a see-through optical system has been proposed in order to superimpose image light and external light (Patent Document 1). In Patent Document 1, a hologram element is provided on a slope formed by combining a prism and a transparent substrate, so that image light can be reflected while allowing external light to pass through without being distorted. In order to form a slope, the two optical components are joined together with an adhesive. In this case, in Patent Document 1, from the viewpoint of ensuring safety, the side surface of the optical component on which the hologram element is provided is inclined so as to spread in a direction away from the eyeball, thereby bonding the joint portion. When peeled off, the optical component is prevented from falling to the eyeball side of the head mounted display wearer. In addition, when bonding members constituting a head-mounted display, there is known a device that adjusts the relationship of the adhesive force to easily remove excess adhesive that protrudes from the surface of the member (see Patent Document 2).

  However, in the apparatus described in Patent Document 1 or the like, in the joint portion where the see-through observation is performed, the solvent contained in the adhesive for bonding dissolves the periphery of the adhesive portion, and the like, thereby affecting the optical element such as the hologram element. If it is given, there is a possibility that the image observed by image light or external light will deteriorate. Further, even if Patent Document 2 is used, for example, in an adhesion in which an optical element is sandwiched between members for see-through observation, the optical element is not necessarily bonded without being affected by the adhesive. .

JP 2007-240924 A JP 2008-268873 A

  The present invention has been made in view of the problems of the background art described above, and provides a virtual image display device and a virtual image display device that enable see-through observation in a good state while suppressing the deterioration of an optical element that forms a virtual image. An object is to provide a manufacturing method.

  In order to solve the above problems, a virtual image display device according to the present invention includes (a) an image display device that forms image light, and (b) a projection optical system that forms a virtual image by image light emitted from the image display device. (C) A light incident part that takes in the image light that has passed through the projection optical system, and a light guide that guides the image light taken from the light incident part by total reflection on the first and second surfaces extending opposite to each other. And a light emitting device that takes out image light that has passed through the light guide portion to the outside, and (d) the light guide device bends the image light and emits external light in the light emitting portion. It has a reflective part to be transmitted and a coat layer covering the reflective part.

  In the virtual image display device, the reflecting portion is covered with a coat layer. Therefore, when a transparent member is bonded from the side that transmits external light to the reflective portion, for example, in order to transmit the external light without distortion and enable see-through observation, a coating layer is interposed in the bonded portion. Thus, it is possible to avoid a situation in which the reflecting portion is affected by an adhesive containing a solvent or the like and its optical characteristics are deteriorated. Since the reflection portion is accurately protected, the state of reflecting the image light that is the optical function of the reflection portion and transmitting the external light is appropriately maintained, and see-through observation in a good state is possible. Note that the reflection portion includes various ones that fold image light and transmit external light. In other words, not only a semi-transmissive reflective film formed by forming a metal reflective film or a dielectric multilayer film on the reflective portion, but also a semi-transmissive member having a semi-transmissive reflectivity, a semi-transmissive sheet, It is assumed that various semi-transmissive reflective portions (semi-transmissive reflective portions) such as hologram elements that act only on light of a wavelength and transmit light of other wavelengths are included.

  In a specific aspect of the present invention, the light guide device has a facing surface facing the reflecting portion, and allows the observation of external light by joining the facing surface and the reflecting portion through the coat layer. A light transmissive member constituting the portion. In this case, the see-through observation without distortion can be performed by the fluoroscopic part.

  In another aspect of the present invention, the light transmissive member includes a facing surface forming layer that is formed of the same material as the coat layer and forms the facing surface. In this case, for example, the bondability of the light transmission member can be improved by selecting a material commonly used for the coat layer and the facing surface forming layer.

  In still another aspect of the present invention, the main body portion of the light guide member including the light guide portion in the light guide device and the main body portion of the light transmission member are made of the same material. In this case, the difference in refractive index between the main body portion of the light guide member and the main body portion of the light transmission member can be eliminated.

  In still another aspect of the present invention, the material of the main body portion of the light guide member and the main body portion of the light transmission member is a cycloolefin polymer. In this case, it is possible to provide high light transmittance and to particularly suppress the hygroscopicity, and it is possible to perform see-through observation in a better state.

  In still another aspect of the present invention, the main body portion of the light guide member including the light guide portion in the light guide device and the main body portion of the light transmission member are made of different materials having the same refractive index. In this case, materials used on the light guide member side and the light transmission member side can be selected according to various purposes.

  In still another aspect of the present invention, the coat layer is a hard coat layer that protects at least a surface that contributes to guiding image light including the first and second surfaces. In this case, the hard coat layer can prevent the surface from being damaged and the resolution of the image from being lowered.

  In still another aspect of the present invention, the coating layer is formed by applying a coating material by dipping. In this case, a film having a desired thickness can be uniformly formed even if the shape of the light guide device is relatively complicated.

  In still another aspect of the present invention, the light guide unit includes the first surface and the second surface that are arranged in parallel to each other and enable light guide by total reflection, and the light incident unit includes The third surface has a predetermined angle with respect to the first surface, and the light emitting unit has a fourth surface with a predetermined angle with respect to the first surface. In this case, image lights having different numbers of reflections can be combined at the same time and taken out as image light for forming one virtual image, so that a large display size of the virtual image observed through the light emitting portion can be secured.

  In still another aspect of the present invention, the reflecting portion is formed on the fourth surface. In this case, a see-through portion that allows see-through can be formed on the fourth surface.

  In order to solve the above problems, a method for manufacturing a virtual image display device according to the present invention includes: (a) an image display device that forms image light; and (b) a projection that forms a virtual image by image light emitted from the image display device. An optical system, (c1) a light incident part that captures image light that has passed through the projection optical system, and (c2) all of the first and second surfaces that extend opposite to each other that capture the image light captured from the light incident part. Light transmission constituting a see-through unit that enables observation of external light by combining a light guide unit that leads by reflection, (c3) a light emission unit that extracts image light that has passed through the light guide unit, and (c4) a light emission unit And (c) a light guide device having a member, and (c) a light guide device that is disposed between the light emitting portion and the light transmitting member and bends image light and transmits external light. (D) The reflecting part is arranged on the light emitting part side. A reflecting portion manufacturing step, (e) a coating layer forming step for forming a coating layer covering the reflecting portion manufactured in the reflecting portion manufacturing step, and (f) a coating layer being covered in the coating layer forming step. A joining step of joining the light emitting part and the light transmitting member so as to sandwich the reflecting part therebetween.

  In the manufacturing method of the virtual image display device, the reflective part produced in the reflective part production process is covered with the coat layer formed in the coat layer film formation process. Therefore, in order to allow the outside light to pass through without being distorted and enable see-through observation, a coating layer is interposed in the joining portion in the joining step of joining the transparent member from the side that transmits the outside light to the reflecting portion. Thus, it is possible to avoid a situation in which the reflecting portion is affected by an adhesive containing a solvent or the like and its optical characteristics are deteriorated. As a result, in the manufactured virtual image display device, the reflecting portion is accurately protected, so that the state of reflecting the image light that is the optical function of the reflecting portion and transmitting the external light is appropriately maintained, and the good state See-through observation is possible.

  In a specific aspect of the present invention, the coating layer forming step includes a dip processing step of applying a coating material to be a coating layer by dip processing. In this case, even if the shape of the manufactured light guide device is relatively complicated, a film having a desired thickness can be uniformly formed.

It is a perspective view which shows the virtual image display apparatus of embodiment. (A) is a top view of the main-body part of the 1st display apparatus which comprises a virtual image display apparatus, (B) is a front view of a main-body part. (A) is the conceptual diagram which expand | deployed the optical path regarding the vertical 1st direction, (B) is the conceptual diagram which expand | deployed the optical path regarding the horizontal 2nd direction. It is a top view explaining the optical path in the optical system of a virtual image display apparatus concretely. (A) shows the display surface of a liquid crystal display device, (B) is a figure explaining notionally the virtual image of the liquid crystal display device which an observer can see, (C) and (D) comprise a virtual image It is a figure explaining the partial image to do. (A) is a figure which shows the light guide device before film-forming of a coat layer, (B) is a figure which shows the light guide member and light transmissive member after film-forming of a coat layer, (C) It is a figure which shows the state which joined the light guide member and the light transmissive member, and (D) is a figure which shows the state which gave the antireflection coating. (A) is a figure which shows the light guide member before the film-forming of the coat layer in manufacture of the virtual image display apparatus of a modification, (B) shows the light guide member and the light transmissive member after the film-forming of the coat layer. (C) is a figure which shows the state which joined the light guide member and the light transmissive member, and (D) is a figure which shows the state which gave the antireflection coating. (A) is a front view of a light guide member, (B) is a bottom view of the light guide member, (C) is a left side view of the light guide member, and (D) is a right side surface of the light guide member. FIG. (A) is a rear view of the light transmitting member, (B) is a BB cross-sectional view of the light transmitting member, (C) is a left side view of the light transmitting member, and (D) is a right side of the light transmitting member. FIG. (A) is a figure which shows the modification of the 1st display apparatus which comprises a virtual image display apparatus, (B) is a figure which shows another modification of a 1st display apparatus. It is a figure which shows another modification of the 1st display apparatus which comprises a virtual image display apparatus.

  Hereinafter, a virtual image display device according to an embodiment of the present invention will be described in detail with reference to the drawings.

[A. Appearance of virtual image display device)
A virtual image display device 100 according to the embodiment shown in FIG. 1 is a head-mounted display having an appearance like glasses, and allows an observer wearing the virtual image display device 100 to recognize image light due to a virtual image. It is possible to make the observer observe the external image with see-through. The virtual image display device 100 includes an optical panel 110 that covers the viewer's eyes, a frame 121 that supports the optical panel 110, and first and second drive units 131 and 132 that are added to a portion of the frame 121 from the end to the temple. With. Here, the optical panel 110 has a first panel portion 111 and a second panel portion 112, and both the panel portions 111 and 112 are plate-like parts integrally connected at the center. The first display device 100A in which the first panel portion 111 on the left side and the first drive unit 131 are combined in the drawing is a portion that forms a virtual image for the left eye, and functions alone as a virtual image display device. Further, the second display device 100B in which the second panel portion 112 on the right side and the second driving unit 132 in the drawing are combined is a portion that forms a virtual image for the right eye, and functions alone as a virtual image display device.

[B. Display device structure]
As shown in FIG. 2A and the like, the first display device 100A includes an image forming device 10 and a light guide device 20. Here, the image forming apparatus 10 corresponds to the first driving unit 131 in FIG. 1, and the light guide device 20 corresponds to the first panel portion 111 in FIG. Note that the second display device 100B shown in FIG. 1 has the same structure as the first display device 100A and is simply flipped left and right, and thus detailed description of the second display device 100B is omitted.

  The image forming apparatus 10 includes an image display device 11 and a projection optical system 12. Among these, the image display device 11 operates the illumination device 31 that emits the two-dimensional illumination light SL, the liquid crystal display device 32 that is a transmissive spatial light modulation device, and the operations of the illumination device 31 and the liquid crystal display device 32. And a drive control unit 34 for controlling.

  The illuminating device 31 includes a light source 31a that generates light including three colors of red, green, and blue, and a backlight light guide unit 31b that diffuses light from the light source 31a into a light beam having a rectangular cross section. The liquid crystal display device 32 spatially modulates the illumination light SL from the illumination device 31 to form image light to be a display target such as a moving image. The drive control unit 34 includes a light source drive circuit 34a and a liquid crystal drive circuit 34b. The light source driving circuit 34a supplies electric power to the light source 31a of the lighting device 31 to emit the illumination light SL having a stable luminance. The liquid crystal driving circuit 34b outputs an image signal or a driving signal to the liquid crystal display device 32, thereby forming color image light that is a source of a moving image or a still image as a transmittance pattern. The liquid crystal driving circuit 34b can have an image processing function, but an external control circuit can also have an image processing function. The projection optical system 12 is a collimating lens that converts image light emitted from each point on the liquid crystal display device 32 into light beams in a parallel state.

  In the liquid crystal display device 32, the first direction D1 is a direction in which a longitudinal section including a first optical axis AX1 passing through the projection optical system 12 and a specific line parallel to a third reflecting surface 21c of the light guide member 21 described later extends. The second direction D2 corresponds to a direction in which a transverse section including the first optical axis AX1 and the normal line of the third reflecting surface 21c extends. That is, at the position of the liquid crystal display device 32, the first direction D1 corresponds to the vertical Y direction, and the second direction D2 corresponds to the horizontal X direction.

  The light guide device 20 is formed by joining a light guide member 21 and a light transmission member 23, and constitutes a flat plate-like optical member that extends parallel to the XY plane as a whole.

  Of the light guide device 20, the light guide member 21 is a trapezoidal prism-like member in plan view, and includes a first reflecting surface 21 a and a second reflecting surface as first to fourth surfaces constituting the side surface. 21b, a third reflecting surface 21c, and a fourth reflecting surface 21d. The light guide member 21 includes a first side surface (upper surface) 21e and a second side surface (which are adjacent to the first, second, third, and fourth reflecting surfaces 21a, 21b, 21c, and 21d and face each other). Lower surface) 21f. Here, the first and second reflecting surfaces 21 a and 21 b extend along the XY plane and are separated by the thickness t of the light guide member 21. The third reflecting surface 21c is inclined at an acute angle α of 45 ° or less with respect to the XY plane, and the fourth reflecting surface 21d is inclined at an acute angle β of 45 ° or less with respect to the XY surface, for example. . The first optical axis AX1 passing through the third reflecting surface 21c and the second optical axis AX2 passing through the fourth reflecting surface 21d are arranged in parallel and separated by a distance D. As will be described in detail below, an end surface 21h is provided between the first reflecting surface 21a and the third reflecting surface 21c so as to remove a ridge. The light guide member 21 has a polyhedral outer shape with seven surfaces including the end surface 21h.

  The light guide member 21 performs light guide using total reflection by the first and second reflection surfaces 21a and 21b, which are first and second surfaces extending opposite to each other, and is folded back by reflection at the time of light guide. And a direction that is not folded back by reflection when light is guided. When an image guided by the light guide member 21 is considered, the lateral direction that is folded back by a plurality of reflections during light guide, that is, the confinement direction DW2, is perpendicular to the first and second reflecting surfaces 21a and 21b (parallel to the Z axis). ) Corresponds to the second direction D2 of the liquid crystal display device 32 when the optical path is expanded to the light source side as will be described later. On the other hand, the longitudinal direction, that is, the non-confining direction DW1 that propagates without being folded back by reflection during light guide is parallel to the first and second reflecting surfaces 21a, 21b and the third reflecting surface 21c (parallel to the Y axis), which will be described later. Thus, when the optical path is developed to the light source side, it corresponds to the first direction D1 of the liquid crystal display device 32. In the light guide member 21, the main light direction in which the propagated light beam travels as a whole is the -X direction.

  The light guide member 21 is formed of a resin material that exhibits high light transmittance in the visible range. The light guide member 21 includes a block-shaped member integrally molded by injection molding as a main body portion 20a. The main body portion 20a is formed by, for example, injecting a heat or photopolymerization type resin material into a molding die to perform thermosetting or light. It is formed by curing. As described above, the light guide member 21 has the main body portion 20a as an integrally formed product, but it can be functionally divided into a light incident part B1, a light guide part B2, and a light emission part B3.

  The light incident part B1 is a triangular prism-shaped part, and includes a light incident surface IS that is a part of the first reflective surface 21a and a third reflective surface 21c that faces the light incident surface IS. The light incident surface IS is a flat surface on the back side or the viewer side for taking in the image light GL from the image forming apparatus 10 and extends perpendicularly to the first optical axis AX1 facing the projection optical system 12. The third reflecting surface 21c has a rectangular outline, and a mirror layer that is a total reflection mirror for reflecting the image light GL that has passed through the light incident surface IS and guiding it into the light guide B2 over the entire rectangular area. 25. The mirror layer is formed by forming a film by vapor deposition of aluminum or the like on the slope RS of the main body portion 20a of the light guide member 21. The third reflecting surface 21c is inclined with respect to the first optical axis AX1 or the XY plane of the projection optical system 12, for example, at an acute angle α = 25 ° to 27 °, and is incident from the light incident surface IS in the + Z direction as a whole. The image light GL that is directed is bent so as to be directed in the −X direction that is closer to the −Z direction as a whole, so that the image light GL is reliably coupled into the light guide portion B2.

  The light guide B2 has first and second reflecting surfaces 21a and 21b that totally reflect the image light bent by the light incident portion B1 as two planes that face each other and extend parallel to the XY plane. Yes. The distance between the first and second reflecting surfaces 21a and 21b, that is, the thickness t of the light guide member 21 is, for example, about 9 mm. Here, it is assumed that the first reflecting surface 21a is on the back side or the viewer side close to the image forming apparatus 10, and the second reflecting surface 21b is on the front side or the outside side far from the image forming apparatus 10. In this case, the first reflecting surface 21a is a surface portion common to the above-described light incident surface IS and a light emitting surface OS described later. The first and second reflection surfaces 21a and 21b are total reflection surfaces using a difference in refractive index and are not provided with a reflective coating such as a mirror layer, but prevent damage to the surface and prevent a reduction in image resolution. Therefore, it is covered with a hard coat layer CC1, which is a coat layer. If necessary, it may be further coated with an antireflection coating AR.

  The image light GL reflected by the third reflecting surface 21c of the light incident part B1 first enters the first reflecting surface 21a and is totally reflected. Next, the image light GL enters the second reflecting surface 21b and is totally reflected. By repeating this operation thereafter, the image light is guided to the leading light direction on the back side of the light guide device 20 as a whole, that is, to the + Z side where the light emitting part B3 is provided. In addition, since the 1st and 2nd reflective surfaces 21a and 21b are not provided with the reflective coating, the external light or the external light incident on the second reflective surface 21b from the external side passes through the light guide B2 with high transmittance. pass. In other words, the light guide B2 is a see-through type that allows the external image to be seen through.

  The light emission part B3 is a triangular prism-shaped part, and has a light emission surface OS that is a part of the first reflection surface 21a and a fourth reflection surface 21d that faces the light emission surface OS. The light exit surface OS is a flat surface on the back side for emitting the image light GL toward the observer's eye EY. The light exit surface OS is a part of the first reflecting surface 21a like the light incident surface IS. It extends perpendicular to the optical axis AX2. The distance D between the second optical axis AX2 passing through the light emitting part B3 and the first optical axis AX1 passing through the light incident part B1 is set to, for example, 50 mm in consideration of the width of the observer's head. The fourth reflecting surface 21d is a rectangular flat surface, reflects the image light GL that has entered through the first and second reflecting surfaces 21a and 21b, emits the light outside the light emitting portion B3, and transmits the external light. A half mirror layer 28 which is a reflection part (semi-transmission reflection part). That is, the half mirror layer 28 is a transflective film having light transmittance. The half mirror layer (semi-transmissive reflective film) 28 is formed by forming a metal reflective film or a dielectric multilayer film of, for example, silver on the inclined surface RR constituting the fourth reflective surface 21d of the light guide member 21. The The reflectance of the half mirror layer 28 with respect to the image light GL is set to 10% to 50% in the assumed incident angle range of the image light GL from the viewpoint of facilitating observation of the external light GL ′ by see-through. The reflectance of the half mirror layer 28 of the specific embodiment with respect to the image light GL is set to 20%, for example, and the transmittance with respect to the image light GL is set to 80%, for example.

  The fourth reflecting surface 21d is inclined with respect to the second optical axis AX2 or XY plane perpendicular to the first reflecting surface 21a, for example, at an acute angle α = 25 ° to 27 °, and is guided by the half mirror layer 28. The image light GL incident through the first and second reflecting surfaces 21a and 21b of the portion B2 is partially reflected and bent so as to be directed in the −Z direction as a whole, thereby allowing the light exit surface OS to pass therethrough. The fourth reflecting surface 21d is also a surface that partially transmits the external light GL ′ and allows the light exit surface OS to pass therethrough, and is a transflective surface. The component of the image light transmitted through the fourth reflecting surface 21d is incident on the light transmitting member 23 and is not used for forming an image.

  In the present embodiment, a hard coat layer CC1, which is a coat layer covering the first and second reflection surfaces 21a and 21b, is also provided on the half mirror layer 28 of the fourth reflection surface 21d. Therefore, the half mirror layer 28 is protected by the hard coat layer CC1.

  The light transmission member 23 is made of the same material as the main body of the light guide member 21 and has the same refractive index, and has a first surface 23a, a second surface 23b, and a third surface 23c. The first and second surfaces 23a and 23b extend along the XY plane. The third surface 23 c is inclined with respect to the XY plane, and is disposed in parallel to face the fourth reflecting surface 21 d of the light guide member 21. That is, the light transmission member 23 has a wedge-shaped member sandwiched between the second surface 23b and the third surface 23c. Similar to the light guide member 21, the light transmissive member 23 is formed of a resin material exhibiting high light transmittance in the visible region. The light transmitting member 23 is a block-like member integrally formed by injection molding, and is formed by, for example, injecting a heat or photopolymerization type resin material into a molding die and thermosetting or photocuring. . A hard coat layer CC2 made of the same material as the hard coat layer CC1 is applied to the surface of the light transmission member 23.

  In the light transmission member 23, the first surface 23 a is disposed on the extended plane of the first reflecting surface 21 a provided on the light guide member 21, is on the back side close to the observer's eye EY, and the second surface 23 b is guided. It is arranged on the extended plane of the second reflecting surface 21b provided on the optical member 21, and is on the front side far from the observer's eye EY. The third surface 23c is a rectangular light transmission surface joined to the fourth reflection surface 21d of the light guide member 21 by an adhesive. The angle formed by the first surface 23a and the third surface 23c is equal to the angle ε formed by the second reflective surface 21b and the fourth reflective surface 21d of the light guide member 21, and the second surface 23b and the third surface 23c are the same. The angle formed with the surface 23 c is equal to the angle β formed between the first reflecting surface 21 a and the third reflecting surface 21 c of the light guide member 21.

  The light transmission member 23 and the light guide member 21 constitute a see-through portion B4 at the joint portion between them and the vicinity thereof. That is, since the first and second surfaces 23a and 23b are not provided with a reflective coating such as a mirror layer, the external light GL ′ is transmitted with a high transmittance similarly to the light guide part B2 of the light guide member 21. . The third surface 23c can also transmit the external light GL ′ with high transmittance, but since the fourth reflecting surface 21d of the light guide member 21 has the half mirror layer 28, the third surface 23c passes through the third surface 23c. The ambient light GL ′ to be reduced is reduced by 20%, for example. That is, the observer observes the image light GL that has been reduced to 20% and the external light GL ′ that has been reduced to 80%.

  In the configuration of the see-through portion B4, that is, in joining the light transmitting member 23 and the light guide member 21, the half mirror layer 28 is sandwiched at the joining portion. In such bonding, for example, the solvent contained in the adhesive may erode the half mirror layer 28 by dissolving the bonded portion, and as a result, the image observed by image light or external light may deteriorate. There is. In the present embodiment, the half mirror layer 28 is not affected by the adhesive by protecting the half mirror layer 28 with the hard coat layer CC1 before joining the light transmitting member 23 and the light guide member 21. I have to.

[C. Overview of optical path of image light)
FIG. 3A is a view for explaining an optical path in the first direction D1 corresponding to the longitudinal section CS1 of the liquid crystal display device 32. FIG. In the longitudinal section along the first direction D1, that is, the YZ plane (the unfolded Y′Z ′ plane), among the image light emitted from the liquid crystal display device 32, the upper end side of the display area 32b indicated by the alternate long and short dash line in FIG. The component emitted from the (+ Y side) is referred to as image light GLa, and the component emitted from the lower end side (−Y side) of the display area 32b indicated by the two-dot chain line in the drawing is referred to as image light GLb.

The upper image light GLa is converted into a parallel light flux by the projection optical system 12 and passes through the light incident part B1, the light guide part B2, and the light emission part B3 of the light guide member 21 along the developed optical axis AX ′. The incident light is incident on the observer's eye EY in a state of a parallel light beam, tilted from above the angle φ ₁ . On the other hand, the lower image light GLb is converted into a parallel light flux by the projection optical system 12, and along the developed optical axis AX ′, the light incident part B <b> 1, the light guide part B <b> 2, and the light emission part of the light guide member 21. The light passes through B3 and is incident on the observer's eye EY in a state of parallel light flux with an inclination from below the angle φ ₂ (| φ ₂ | = | φ ₁ |). The above angles φ ₁ and φ ₂ correspond to the upper and lower half angles of view, and are set to, for example, 6.5 °.

  FIG. 3B is a diagram illustrating an optical path in the second direction (confinement direction DW2 or synthesis direction) D2 corresponding to the cross section CS2 of the liquid crystal display device 32. Among the image lights emitted from the liquid crystal display device 32 in the cross section CS2 along the second direction D2 (the confinement direction DW2 or the synthesis direction), that is, the XZ plane (the X′Z ′ plane after development), The component emitted from the first display point P1 on the right end side (+ X side) toward the display area 32b shown in FIG. 4 is image light GLc, and the left end side (−X side) toward the display area 32b shown by the two-dot chain line in the figure. ) Is emitted from the second display point P2 as image light GLd. In FIG. 3B, for reference, image light GLe emitted from the inner right side and image light GLf emitted from the inner left side are added.

The image light GLc from the first display point P1 on the right side is converted into a parallel light beam by the projection optical system 12, and along the developed optical axis AX ′, the light incident part B1, the light guide part B2, and through the light exit portion B3, a parallel light beam state with respect to the observer's eye EY, incident inclined from right angles theta _1. On the other hand, the image light GLd from the second display point P2 on the left side is converted into a parallel light beam by the projection optical system 12, and along the developed optical axis AX ′, the light incident part B1 and the light guide part of the light guide member 21. The light passes through B2 and the light emitting part B3 and enters the observer's eye EY in a state of a parallel light beam with an angle θ ₂ (| θ ₂ | = | θ ₁ |) inclined from the left direction. The above angles θ ₁ and θ ₂ correspond to the left and right half angles of view, and are set to 10 °, for example.

Note that, in the horizontal direction of the second direction D2, the image lights GLc and GLd are folded back by reflection in the light guide member 21 and the number of reflections is different, so that each image light GLc and GLd is in the light guide member 21. It is expressed discontinuously. In addition, regarding the observer's eye EY, the viewing direction is upside down compared to the case of FIG. As a result, the screen is horizontally reversed as a whole in the horizontal direction, but the right half image of the liquid crystal display device 32 and the liquid crystal display device can be obtained by processing the light guide member 21 with high accuracy as will be described in detail later. The images on the left half of 32 are continuously joined without any gap. In consideration of the fact that the number of reflections of the image light GLc and GLd in the light guide member 21 is different from each other, the emission angle θ ₁ ′ of the right image light GLc and the emission angle θ ₂ ′ of the left image light GLd. Is set to something different.

  As described above, the image lights GLa, GLb, GLc, and GLd incident on the observer's eye EY are virtual images from infinity, and the image formed on the liquid crystal display device 32 is correct in the first vertical direction D1. The image formed on the liquid crystal display device 32 is reversed with respect to the second horizontal direction D2.

[D. (The optical path of image light in the horizontal direction)
FIG. 4 is a cross-sectional view illustrating a specific optical path in the first display device 100A. The projection optical system 12 has three lenses L1, L2, and L3.

The image lights GL11 and GL12 from the first display point P1 on the right side of the liquid crystal display device 32 pass through the lenses L1, L2, and L3 of the projection optical system 12 to be converted into parallel light beams, and the light incident surface of the light guide member 21 Incident on IS. The image lights GL11 and GL12 guided into the light guide member 21 repeat total reflection at the same angle on the first and second reflection surfaces 21a and 21b, and are finally emitted as a parallel light flux from the light exit surface OS. . Specifically, the image lights GL11 and GL12 are reflected by the third reflection surface 21c of the light guide member 21 as parallel light beams, and then enter the first reflection surface 21a of the light guide member 21 at the first reflection angle γ1. , Total reflection (first total reflection). Thereafter, the image lights GL11 and GL12 are incident on the second reflecting surface 21b and totally reflected (second total reflection) while maintaining the first reflection angle γ1, and then incident on the first reflecting surface 21a again. And is totally reflected (third total reflection). As a result, the image lights GL11 and GL12 are totally reflected three times on the first and second reflecting surfaces 21a and 21b, and enter the fourth reflecting surface 21d. The image lights GL11 and GL12 are reflected by the fourth reflection surface 21d at the same angle as the third reflection surface 21c, and are angled from the light emission surface OS to the second optical axis AX2 direction perpendicular to the light emission surface OS. It is emitted as a parallel light beam by theta ₁ slope.

The image lights GL21 and GL22 from the second display point P2 on the left side of the liquid crystal display device 32 pass through the lenses L1, L2, and L3 of the projection optical system 12 to be converted into parallel light beams, and the light incident surface of the light guide member 21 Incident on IS. The image lights GL21 and GL22 guided into the light guide member 21 repeat total reflection at equal angles on the first and second reflection surfaces 21a and 21b, and are finally emitted from the light exit surface OS as parallel light beams. . Specifically, the image lights GL21 and GL22 are reflected by the third reflecting surface 21c of the light guide member 21 as a parallel light beam, and then the first reflection of the light guide member 21 at the second reflection angle γ2 (γ2 <γ1). The light enters the surface 21a and is totally reflected (first total reflection). Thereafter, the image lights GL21 and GL22 enter the second reflection surface 21b and are totally reflected (second total reflection) while maintaining the second reflection angle γ2, and then enter the first reflection surface 21a again. Are totally reflected (third total reflection), are incident again on the second reflecting surface 21b and totally reflected (fourth total reflection), and are again incident on the first reflecting surface 21a and totally reflected. (5th total reflection). As a result, the image lights GL21 and GL22 are totally reflected five times on the first and second reflecting surfaces 21a and 21b and enter the fourth reflecting surface 21d. The image lights GL21 and GL22 are reflected by the fourth reflecting surface 21d at the same angle as the third reflecting surface 21c, and are angled from the light emitting surface OS to the second optical axis AX2 direction perpendicular to the light emitting surface OS. It is emitted as a parallel light beam by theta ₂ gradient.

  In FIG. 4, when the light guide member 21 is developed, a virtual first surface 121a corresponding to the first reflection surface 21a, and when the light guide member 21 is deployed, a virtual first surface 121b corresponding to the second reflection surface 21b. The 2nd surface 121b is drawn. By developing in this way, the image lights GL11 and GL12 from the first display point P1 pass through the first surface 121a twice after passing through the incident equivalent surface IS ′ corresponding to the light incident surface IS. It can be seen that the light passes through the surface 121b once, is emitted from the light exit surface OS, and enters the observer's eye EY, and the image lights GL21 and GL22 from the second display point P2 are incident corresponding to the light entrance surface IS. After passing through the equivalent surface IS ", it can be seen that it passes through the first surface 121a three times, passes through the second surface 121b twice, is emitted from the light exit surface OS, and enters the observer's eye EY. In other words, the observer observes the lens L3 of the projection optical system 12 existing in the vicinity of the two incident equivalent planes IS ′ and IS ″ at two different positions.

  FIG. 5A is a diagram for conceptually explaining the display surface of the liquid crystal display device 32, and FIG. 5B is a diagram for conceptually explaining a virtual image of the liquid crystal display device 32 that can be seen by an observer. FIGS. 5C and 5D are diagrams illustrating partial images constituting a virtual image. A rectangular image forming area AD provided in the liquid crystal display device 32 shown in FIG. 5A is observed as a virtual image display area AI shown in FIG. On the left side of the virtual image display area AI, a first projection image IM1 corresponding to a portion from the center to the right side of the image forming area AD of the liquid crystal display device 32 is formed. This first projection image IM1 is shown in FIG. ) As shown in FIG. Further, on the right side of the virtual image display area AI, a projection image IM2 corresponding to a portion from the center to the left side of the image formation area AD of the liquid crystal display device 32 is formed as a virtual image. This second projection image IM2 is shown in FIG. As shown in (D), the left half is a partial image.

  The first partial region A10 that forms only the first projection image (virtual image) IM1 in the liquid crystal display device 32 illustrated in FIG. 5A includes the first display point P1 at the right end of the liquid crystal display device 32, for example. The image lights GL11 and GL12 that are totally reflected three times in total in the light guide portion B2 of the light guide member 21 are emitted. The second partial area A20 that forms only the second projection image (virtual image) IM2 in the liquid crystal display device 32 includes, for example, the second display point P2 at the left end of the liquid crystal display device 32, and the light guide member 21 guides the light. The image light GL21 and GL22 that are totally reflected five times in the portion B2 are emitted. The image light from the band SA extending vertically and sandwiched between the first and second partial areas A10 and A20 near the center of the image forming area AD of the liquid crystal display device 32 forms an overlapping image SI shown in FIG. doing. That is, the image light from the band SA of the liquid crystal display device 32 is a total of 5 in the first projection image IM1 formed by the image light GL11 and GL12 totally reflected three times in the light guide B2, and in the light guide B2. The second projected image IM2 formed by the image lights GL11 and GL12 that are totally reflected once is superimposed on the virtual image display area AI. If the light guide member 21 is precisely processed and a light beam accurately collimated by the projection optical system 12 is formed, the overlapping image SI is prevented from being displaced or blurred due to the superimposition of the two projection images IM1 and IM2. be able to.

  In the above, the total number of reflections of the image light GL11 and GL12 emitted from the first partial area A10 including the first display point P1 on the right side of the liquid crystal display device 32 by the first and second reflecting surfaces 21a and 21b is three times in total. Thus, the total number of reflections of the image light GL21 and GL22 emitted from the second partial area A20 including the second display point P2 on the left side of the liquid crystal display device 32 by the first and second reflecting surfaces 21a and 21b is five times in total. However, the total number of reflections can be changed as appropriate. That is, by adjusting the outer shape (that is, thickness t, distance D, acute angles α, β) of the light guide member 21, the total number of reflections of the image light GL11, GL12 is set to five times, and the total reflection number of the image light GL21, GL22 is A total of seven times can be used. In the above description, the total number of reflections of the image lights GL11, GL12, GL21, and GL22 is an odd number. However, if the light incident surface IS and the light exit surface OS are arranged on the opposite side, that is, the light guide member 21. Is a parallelogram type in plan view, the total number of reflections of the image lights GL11, GL12, GL21, and GL22 is an even number.

[E. Manufacturing process of virtual image display device]
Hereinafter, the manufacturing process of the virtual image display device according to the present embodiment will be described with reference to FIGS. Here, a process related to the production of the light guide device 20 by joining the light guide member 21 and the light transmitting member 23, which is a characteristic part of each manufacturing process, will be described.

  First, as shown in FIG. 6A, a main body portion 20a of the light guide member 21 is prepared, and a mirror layer 25 that is a reflective film and a half mirror layer 28 that is a transmissive reflective film are formed. The main body portion 20a is formed of a resin material exhibiting high light transmittance in the visible range. Here, the main body portion 20a is formed by injection molding using, for example, methacrylstyrene or a cycloolefin polymer as a material. The main body portion 20a includes first to fourth surfaces SFa, SFb, which are portions where the first to fourth reflecting surfaces 21a, 21b, 21c, 21d (see FIG. 2A) of the light guide member 21 are to be formed. It has SFc and SFd. Of these surfaces SFa, SFb, SFc, and SFd, a mirror layer 25 is formed by depositing aluminum or the like on a region necessary for reflection of image light on the surface of the third surface SFc that is the inclined surface RS. Then, the third reflecting surface 21c is formed (mirror layer forming step). On the surface of the fourth surface SFd, which is the inclined surface RR, a half mirror layer 28 is formed by depositing silver or the like in a region necessary for reflection of image light and transmission of external light, so that a semi-transmission surface is formed. The fourth reflecting surface 21d is formed (reflecting part manufacturing step).

  Next, as shown in FIG. 6B, a hard coat layer is formed on the surface of the main body portion 20a in a state where the mirror layer 25 and the half mirror layer 28 are formed in the mirror layer forming step and the reflecting portion manufacturing step. CC1 is deposited. The hard coat layer CC1 is formed with a substantially uniform film thickness over the entire surface of the main body portion 20a by applying a coating material, for example, by dipping (coat layer film forming step). The film thickness of the hard coat layer CC1 is desirably about 5 μm. As a result, the shape after the hard coat layer CC1 is formed maintains the shape of the main body portion 20a before the film formation, and the hard coat layer CC1 prevents the main body portion 20a from being damaged and facilitates the removal of dirt. It has a thickness that can function as a hard coat. In this case, the hard coat layer CC1 is a transflective film that covers not only the first and second surfaces SFa, SFb but also the fourth reflective surface 21d, forms a surface S1 on the side facing the light transmissive member 23, and is a transflective film. The half mirror layer 28 is protected. That is, the portion of the hard coat layer CC1 that covers the fourth reflective surface 21d functions as a semi-transmissive reflective layer protective layer, and exists on the inner side of the apparatus when the light transmissive member 23 is bonded. It becomes an intermediate layer. A portion of the hard coat layer CC1 that covers the first and second surfaces SFa and SFb is a surface coat layer that forms an exposed surface. The hard coat layer CC1 protects the mirror layer 25 by covering the third reflection surface 21c, and covers the first and second reflection surfaces 21a, 21b by covering the first and second surfaces SFa, SFb. Forming. As described above, the light guide member 21 having the first to fourth reflective surfaces 21a, 21b, 21c, and 21d is manufactured through the coat layer forming step (light guide member preparing step).

  As shown in FIG. 6B, the light guide member 21 is prepared in the light guide member preparation step, and the light transmission member 23 to be joined to the light guide member 21 is prepared (light transmission member preparation step). . The light transmissive member 23 includes a main body portion 24a and a hard coat layer CC2. That is, the light transmission member 23 is formed by forming the hard coat layer CC2 on the surface of the main body portion 24a. The hard coat layer CC2 is made of the same material as the hard coat layer CC1 of the light guide member 21, and forms each surface 23a of the light transmission member 23 and the like. In particular, as the third surface 23c that is the surface facing the light guide member 21, the facing surface S2 that faces the surface S1 that is located on the fourth reflecting surface 21d side that is the semi-transmissive surface of the light guide member 21 is the hard coat layer CC2. Formed by. In other words, the hard coat layer CC2 is a facing surface forming layer that forms the facing surface S2. The hard coat layer CC2 can also be formed with a desired film thickness by applying a coating material, for example, by dipping. The main body portion 24a is formed by injection molding or the like with the same material as the main body portion 20a.

  Next, as shown in FIG. 6C, the light guide member 21 and the light transmission member 23 are attached to the surface S1 of the light guide member 21 and the facing surface S2 of the light transmission member 23 with an adhesive or the like. By joining, it joins (joining process).

  If necessary, as shown in FIG. 6D, an antireflection coating AR may be further formed on the light guide member 21 and the light transmission member 23 which are joined and integrated in the joining step (reflection). Prevention coating film forming step). Thus, the light guide device 20 is manufactured.

  Moreover, about the light guide member 21 of the light guide device 20 manufactured as described above, for example, when the antireflection coating AR is not applied, as shown in FIG. The first and second reflecting surfaces 21a and 21b are formed by the interface between the hard coat layer CC1 located in the outermost layer and the air layer. The third reflecting surface 21c is formed by the interface between the mirror layer 25 and the third surface SFc. The fourth reflecting surface 21d is formed by the interface between the half mirror layer 28 and the fourth surface SFd. As shown in FIG. 6D, when the antireflection coating AR is formed, the interface between the antireflection coating AR and the air layer may be the first and second reflecting surfaces 21a and 21b. it can.

  As described above, in the virtual image display device 100 according to the present embodiment, the half mirror layer 28 that is a semi-transmissive reflective film is covered with the hard coat layer CC1 in the manufacture of the light guide device 20. Therefore, when the light transmitting member 23, which is a transparent member, is bonded in order to transmit outside light in the half mirror layer 28 without distortion, the hard coat layer CC1 is interposed in the bonded portion, and the semi-transmissive reflective film It is possible to avoid a situation in which a certain half mirror layer 28 is affected by an adhesive containing a solvent or the like and the optical characteristics thereof deteriorate. Since the half mirror layer 28 that is a semi-transmissive reflective film is accurately protected, the state of reflecting the image light that is an optical function of the half mirror layer 28 and transmitting the external light is appropriately maintained, and in a good state. See-through observation.

  In the case of this embodiment, in the joining shown in FIG. 6C, the hard coat layer CC1 plays a role as a cushioning material against the action of a physical force such as pressure bonding at the time of bonding. The half mirror layer 28 which is a transmission / reflection film is protected.

  In the case of the present embodiment, since the surfaces S1 and S2 which are joint portions are formed by the hard coat layers CC1 and CC2 made of the same material, an adhesive suitable for adhering the material is used. By using it, it is possible to ensure a sufficient adhesive force. Therefore, as a material for the main body portion 20a of the light guide member 21 and the main body portion 24a of the light transmitting member 23, a cycloolefin polymer that is generally difficult to directly bond can be used. When the cycloolefin polymer is used, the light guide member 21 and the light transmissive member 23 have high light transmissivity, and the hygroscopic property can be particularly suppressed, and see-through observation in a better state becomes possible.

  The total reflection on the first and second reflecting surfaces 21a and 21b depends on the setting of the refractive index of the hard coat layer CC1, and it is also inside the hard coat layer CC1 that is generated on the surface side of the hard coat layer CC1. It can also be generated by the surfaces SFa and SFb.

  Hereinafter, a manufacturing process of a modification of the virtual image display device according to the present embodiment will be described with reference to FIGS. In this modification, as shown in FIGS. 7B to 7D, the main body portion 20a of the light guide member 21 and the main body portion 24a of the light transmission member 23 are made of different materials having the same refractive index. Has been. Note that each step in manufacturing the virtual image display device is similar to the case illustrated in FIG.

  Also in this modification, since the surfaces S1 and S2 which are joint portions are formed by the hard coat layers CC1 and CC2 made of the same material, an adhesive suitable for adhering the material should be used. Thus, even if the main body portions 20a and 24a are made of different materials, a sufficient adhesive force can be ensured.

  Further, by making the main body portions 20a and 24a have the same refractive index, see-through observation in a good state without distortion becomes possible.

[F. Others]
Although the present invention has been described based on the above embodiments, the present invention is not limited to the above embodiments, and can be implemented in various modes without departing from the gist thereof. Such modifications are also possible.

  In the above embodiment, the hard coat layer CC1 is used as a coat layer that covers the half mirror layer 28 that is a semi-transmissive reflective film. However, the semi-transmissive reflective film may be covered with a coat layer other than the hard coat layer. . In addition, when the antireflection coating AR is applied, the film is formed after the light guide member 21 and the light transmitting member 23 are joined. However, after the hard coat layer CC1 is formed, the light guide member 21 and the light transmitting member 23 are formed. A configuration in which the half mirror layer 28 is covered with the hard coat layer CC1 and the antireflection coating AR by forming the antireflection coating AR before the bonding with the transmissive member 23 is also conceivable.

  The shape of the light transmissive member 23 is not limited to the shape in which the light guide member 21 extends laterally, that is, in the X direction, and may include a portion that is extended so as to sandwich the light guide member 21 from above and below. For example, combinations of the light guide member 21 and the light transmissive member 23 as shown in FIGS. 8A to 8D and FIGS. 9A to 9D are possible. Even in the case of the light guide member 21 and the light transmission member 23 having relatively complicated shapes, for example, by forming the hard coat layers CC1 and CC2 by dipping, a relatively thin film can be uniformly formed on the whole. A film can be formed. In addition, about the film-forming method of the hard-coat layers CC1 and CC2, not only a dipping process but a normal coat system, a spray system, a roll coat system, a wet coat system, etc. are applicable. When the shape of the light guide member 21 or the like is relatively simple, the hard coat layers CC1 and CC2 having a desired film thickness can be formed by various methods as described above.

  In the above embodiment, the half mirror layer 28 that is a transflective portion is a transflective film formed by depositing a metal reflective film or a dielectric multilayer film made of silver or the like, but is not limited thereto. The transflective portion may be configured by a transflective member having transflective properties, a translucent sheet, or the like. Further, for example, as shown in FIG. 10A, a third reflecting surface 21c or a fourth reflecting surface is replaced by hologram elements HE1 and HE2 instead of the mirror layer 25 and the half mirror layer 28 (see FIG. 2A). 21d may be formed. That is, the transflective portion that bends the image light and transmits the external light may be configured by the hologram element HE2. In this case, the image display device 11 has, for example, an LED light source that generates light beams of three colors as a light source, and the hologram elements HE1 and HE2 have a hologram layer having a three-layer structure corresponding to the three colors. . Accordingly, the hologram elements HE1 and HE2 have a function of reflecting each color light from the image display device 11 in a desired direction as virtual mirrors formed in the vicinity of the third reflecting surface 21c and the fourth reflecting surface 21d. It will have. That is, the hologram element 825 can adjust the reflection direction of the image light. Further, when the hologram elements HE1 and HE2 are used, each color light can be reflected in a desired direction. Therefore, for example, as shown in FIG. 10B, the first and second reflecting surfaces 21a are formed by extending the second reflecting surface 21b without inclining the third and fourth reflecting surfaces 21c and 21d with respect to the first reflecting surface 21a. The hologram elements HE1 and HE2 may be formed on a plane parallel to. In addition, since the hologram element HE2 acts only on light in a specific wavelength band and transmits light in other wavelength bands, see-through observation is possible by allowing external light to pass through.

  In the above description, the light guide device 20 including the light incident part B1, the light guide part B2, and the light emitting part B3 is used. However, in the light incident part B1 and the light emitting part B3, it is not necessary to use a plane mirror. A lens-like function can be provided by a spherical or aspherical curved mirror. Furthermore, as shown in FIG. 11, a prism or block-shaped relay member 1125 separated from the light guide B2 can be used as the light incident part B1, and the incident and outgoing surfaces and the reflective inner surface of the relay member 1125 are lens-like. It can also have a special function. In addition, although the light guide 26 which comprises the light guide part B2 is provided with the 1st and 2nd reflective surfaces 21a and 21b which are the 1st and 2nd surfaces which propagate image light GL by reflection, These reflecting surfaces 21a and 21b do not need to be parallel to each other, and may be curved surfaces.

  In the above embodiment, the illumination light SL from the illumination device 31 is not particularly directed, but the illumination light SL can be provided with directivity corresponding to the position of the liquid crystal display device 32. As a result, the liquid crystal display device 32 can be efficiently illuminated, and luminance unevenness due to the position of the image light GL can be reduced.

  In the above embodiment, the display brightness of the liquid crystal display device 32 is not particularly adjusted, but the display brightness may be adjusted according to the range and overlap of the projection images IM1 and IM2 as shown in FIG. it can.

  In the above-described embodiment, the transmissive liquid crystal display device 32 or the like is used as the image display device 11. However, the image display device 11 is not limited to the transmissive liquid crystal display device 32, and various devices can be used. . For example, a configuration using a reflective liquid crystal display device is possible, and a digital micromirror device or the like can be used instead of the liquid crystal display device 32. Further, as the image display device 11, a self-luminous element represented by an LED array, an OLED (organic EL), or the like can be used.

  In the virtual image display device 100 of the above-described embodiment, the image forming device 10 and the light guide device 20 are provided one by one corresponding to both the right eye and the left eye, but either the right eye or the left eye. Only the image forming apparatus 10 and the light guide device 20 may be provided for only one eye.

  In the above embodiment, the first optical axis AX1 passing through the light incident surface IS and the second optical axis AX2 passing through the light incident surface IS are parallel, but these optical axes AX1 and AX2 are made non-parallel. You can also.

  In the above description, the virtual image display device 100 has been specifically described as being a head-mounted display, but the virtual image display device 100 can be modified to a head-up display.

  In the above description, in the first and second reflecting surfaces 21a and 21b, image light is totally reflected and guided by the interface with air without applying a mirror, a half mirror, or the like on the surface. The total reflection includes reflection formed by forming a mirror coat or a half mirror film on the whole or a part of the first and second reflection surfaces 21a and 21b. For example, after the incident angle of the image light satisfies the total reflection condition, the first and second reflection surfaces 21a and 21b are subjected to mirror coating or the like to reflect substantially all the image light. Cases are also included. In addition, as long as image light with sufficient brightness can be obtained, the first and second reflecting surfaces 21a and 21b may be entirely or partially coated with a somewhat transmissive mirror.

  In the above description, the light guide member 21 extends in the horizontal direction in which the eyes EY are arranged. However, the light guide member 21 can be extended in the vertical direction. In this case, the optical panels 110 are arranged in parallel, not in series.

DESCRIPTION OF SYMBOLS 10 ... Image forming apparatus, 11 ... Image display apparatus, 12 ... Projection optical system, 20 ... Light guide apparatus, 20a ... Main-body part, 21 ... Light guide member, 21a, 21b, 21c, 21d ... Reflecting surface, 21e ... 1st Side surface (upper surface), 21f ... second side surface (lower surface), 21h ... end surface, 23 ... light transmitting member, 23a, 23b, 23c ... surface, 24a ... main body portion, 25 ... mirror layer, 28 ... half mirror layer ( Translucent reflection film), 31 ... illumination device, 32 ... liquid crystal display device, 32b ... display region, 34 ... drive control unit, 100 ... virtual image display device, 100A, 100B ... display device, 110 ... optical panel, 121 ... frame, 131, 132 ... drive unit, AX1 ... first optical axis, AX2 ... second optical axis, B1 ... light incident part, B2 ... light guide part, B3 ... light emission part, B4 ... see-through part, CC Adhesive layer, EY ... eye, FS ... flat surface, GL ... image light, GL '... external light, GL11, GL12, GL21, GL22 ... image light, IM1, IM2 ... projected image, IS ... light incident surface, L1, L2 , L3 ... lens, OS ... light exit surface, P1 ... display point, P2 ... display point, SL ... illumination light, CC1 ... hard coat layer (coat layer), CC2 ... hard coat layer (opposite surface forming layer), AR ... Anti-reflection coating

Claims (12)

An image display device for forming image light;
A projection optical system for forming a virtual image by the image light emitted from the image display device;
A light incident part that takes in the image light that has passed through the projection optical system and a light guide that guides the image light taken from the light incident part by total reflection on the first and second surfaces extending opposite to each other. A light guide device, and a light emitting unit for taking out the image light that has passed through the light guide unit to the outside,
With
The light guide device is a virtual image display device having a reflection part that bends the image light and transmits the external light and a coat layer that covers the reflection part in the light emitting part.   The light guide device has a facing surface that faces the reflecting portion, and constitutes a see-through portion that enables observation of external light by joining the facing surface and the reflecting portion through the coat layer. The virtual image display device according to claim 1, comprising a light transmission member.   The virtual image display device according to claim 2, wherein the light transmission member includes a facing surface forming layer that is made of the same material as the coat layer and forms the facing surface.   The main-body part of the light guide member containing the said light guide part among the said light-guide devices, and the main-body part of the said light transmissive member are comprised by the same material as described in any one of Claim 2 and 3. Virtual image display device.   The virtual image display device according to claim 4, wherein a material of the main body portion of the light guide member and the main body portion of the light transmission member is a cycloolefin polymer.   The main body part of the light guide member including the light guide unit in the light guide device and the main body part of the light transmission member are made of different materials having the same refractive index. The virtual image display device according to claim 1.   The virtual image according to any one of claims 1 to 6, wherein the coat layer is a hard coat layer that protects a surface that contributes to guiding the image light including at least the first and second surfaces. Display device.   The virtual image display device according to any one of claims 1 to 7, wherein the coating layer is formed by applying a coating material by dipping. The light guide unit has the first surface and the second surface that are arranged in parallel to each other and enable light guide by total reflection,
The light incident portion has a third surface that forms a predetermined angle with respect to the first surface;
9. The virtual image display device according to claim 1, wherein the light emitting unit has a fourth surface that forms a predetermined angle with respect to the first surface. 10.   The virtual image display device according to claim 9, wherein the reflection unit is formed on the fourth surface. An image display device that forms image light, a projection optical system that forms a virtual image by the image light emitted from the image display device, a light incident portion that takes in the image light that has passed through the projection optical system, and the A light guide unit that guides the image light captured from the light incident unit by total reflection on the first and second surfaces extending opposite to each other; a light emission unit that extracts the image light that has passed through the light guide unit; and A light transmitting member that constitutes a see-through unit that enables observation of external light by combining with a light emitting unit, and is disposed between the light emitting unit and the light transmitting member to bend the image light and to transmit the external light. A light guide device having a reflecting portion to transmit;
A method of manufacturing a virtual image display device comprising:
A reflective part manufacturing step of arranging the reflective part on the light emitting part side;
A coat layer film forming step of forming a coat layer covering the reflective portion manufactured in the reflection manufacturing process;
A bonding step of bonding the light emitting portion and the light transmitting member so as to sandwich the reflective portion covered by the coat layer in the coat layer film forming step;
A method of manufacturing a virtual image display device having   The virtual image display device according to claim 11, wherein the coating layer forming step includes a dip processing step of applying a coating material to be the coating layer by dip processing.

Images