JP6115004B2 - Virtual image display device and method of manufacturing virtual image display device - Google Patents

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 (see Patent Document 1). Moreover, although it is not a technique regarding a head-mounted display, it is known to provide a hard coat layer in order to protect the surface of a resin molded product (see, for example, Patent Document 2).

  In the head mounted display, in order to guide the image light in an appropriate state, it is necessary to maintain a good state of the surface portion of the light guide plate that propagates the image light by reflection or the like. Therefore, it is conceivable to provide a hard coat layer in order to prevent damage to the surface portion or to facilitate removal of dirt on the surface. In particular, in the case of a see-through type head mounted display, the exposed portion of the light guide plate tends to increase, and it is more important to provide a hard coat layer on the surface portion.

  However, the light guide portion including the light guide plate in the head-mounted display tends to have a complicated shape because, for example, a positioning portion for assembling other optical components may be attached to the periphery. In addition, the shape of the light guide portion must be precise in order to guide light accurately. Therefore, when a hard coat layer is formed on an optical component constituting the light guide portion, if a liquid pool or dripping is formed in a place where the coating liquid as a raw material is not intended, a groove provided as a positioning portion or The hole may be filled with coating liquid, resulting in poor assembly accuracy, or the coating liquid may sag on the light guide surface, which should be the light guide part, and the flatness may be impaired and the light guide performance deteriorates. there is a possibility. From the above, it is not always easy to provide the hard coat layer in a desired state so as not to become excessive.

JP 2007-240924 A JP 2009-51920 A

  The present invention has been made in view of the above background art, and while providing a protective hard coat layer, the assembly accuracy is not deteriorated and the light guide performance at the light guide portion is good. It is an object of the present invention to provide a virtual image display device that can be maintained in a state and a method for manufacturing the virtual image display device.

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. (C1) a light incident part that takes in the image light that has passed through the projection optical system, and (c2) a guide that guides the image light taken in from the light incident part by total reflection on the first and second surfaces facing each other. (C) a light guide device having a light portion and (c3) a light emitting portion for taking out image light that has passed through the light guide portion to the outside, and (d) the light guide device is coated with a coating solution and cured. is formed by causing, it possesses a hard coat layer provided on the surface of the contributing light guide portion guiding light of the image light, and a flow control structure for controlling the flow of the applied coating solution, and
The flow control structure is a liquid dripping prevention structure that has a step portion protruding from the peripheral portion of the light guide surface to prevent the coating liquid from dripping to the light guide surface side.

In the virtual image display device, since the light guide device has a flow control structure, when the hard coat layer is formed, the flow of the coating liquid as a raw material is appropriately controlled to Prevents liquid accumulation or dripping caused by the coating liquid from occurring in the area where it is not. As a result, the accuracy of assembly with other optical members is not deteriorated, and the light guide performance in the light guide device can be maintained in a good state, and the flow control structure constitutes a dripping prevention structure The excess coating liquid is dammed up by the stepped portion, and the occurrence of liquid dripping to the region to be the light guide surface can be prevented.

In order to solve the above problems, a virtual image display device according to the present invention includes an image display device that forms image light, a projection optical system that forms a virtual image by image light emitted from the image display device, and a projection optical system. A light incident part that takes in the image light inside, a light guide part that guides the image light taken in from the light incident part by total reflection on the first and second surfaces facing each other, and image light that has passed through the light guide part A light emitting device for taking out the light to the outside, and the light guide device is formed by applying and curing a coating liquid and contributing to the light guide of the image light And a flow control structure for controlling the flow of the applied coating liquid. The flow control structure has a relief groove for the coating liquid around the three-dimensional shape. This is a liquid pool preventing structure that prevents liquid pooling . In this case, the excess coating liquid at the target portion can be removed by the escape groove constituting the liquid pool preventing structure, and the occurrence of liquid pool can be prevented.

  In another aspect of the present invention, the light guide device has a positioning portion that performs relative positioning with other members including the projection optical system, and the liquid pool preventing structure provides a relief groove around the positioning portion. Is formed. In this case, it is possible to prevent the occurrence of a liquid pool in the positioning portion, and to prevent the assembly accuracy from being deteriorated.

  In still another aspect of the present invention, the liquid pool preventing structure has the concave three-dimensional shape at the connecting portion on the distal end side of the support member that supports the light guide unit, and the escape groove is a part of the concave shape. It is a notch part formed by notching. In this case, it is possible to prevent liquid pooling by adjusting the direction of cutout at the cutout portion.

  In still another aspect of the present invention, the flow control structure has a stepped portion where the light guide surface protrudes from the peripheral portion of the light guide surface, and prevents dripping of the coating liquid toward the light guide surface side. Structure. In this case, the excess coating liquid can be dammed up by the step portion constituting the liquid dripping prevention structure, and the occurrence of liquid dripping to the region to be the light guide surface can be prevented.

  In yet another aspect of the present invention, the light guide device includes a light incident part, a light guide part, and a light emitting part, and a see-through part that enables observation of external light by joining the light emitting part. The liquid dripping prevention structure is formed by providing a step portion at the boundary between the light guide member and the light transmissive member. In this case, at the boundary between the light guide member and the light transmission member, it is possible to prevent liquid dripping into the region that should become the light guide surface of the light guide member, and to maintain the light guide performance of the light guide device in a good state.

  In yet another aspect of the present invention, the hard coat layer is formed by applying a coating solution by dipping. In this case, even if the light guide device has a relatively complicated shape, the film thickness of the hard coat layer to be formed is relatively uniform and does not affect the shape of the light guide device. It is thin and can secure a minimum thickness that can function as a hard coat that prevents damage and facilitates removal of dirt.

  In still another aspect of the present invention, in the light guide device, the flow control structure sets the flow path of the coating liquid so as to avoid the light guide surface of the light guide device and the external portion exposed to the outside of the light guide device. doing. In this case, even if the excessive coating liquid is cured and a hard coat layer having an excessive thickness is formed in part, it is possible to prevent the optical function and appearance from being affected.

  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 first surface. A third surface having a predetermined angle with respect to the first surface, and the light emitting portion has a fourth surface having a predetermined angle with respect to the first surface. In this case, for example, image lights having different numbers of reflections can be combined at the same time and taken out as image light that forms one virtual image, so that a large display size of the virtual image observed through the light emitting portion can be secured.

  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) total reflection on the first and second surfaces that oppose the image light captured from the light incident part. (C3) a hard coating layer provided on the surface of the light guide that contributes to the light guide of the image light, and (c5) hardware (C) a light guide device having a flow control structure for controlling the flow of a coating liquid applied to form a coating layer, wherein (d) the coating liquid is A first step of preparing a flow control structure for controlling flow; e) having a second step of forming a hard coat layer by causing the coating to cure the coating solution while controlling the flow of coating liquid by prepared flow control structure in the first step.

  In the virtual image display device manufacturing method, in the second step, by appropriately controlling the flow of the coating liquid that is a raw material of the hard coat layer, the liquid by the coating liquid is applied to an unintended portion of the light guide device to be manufactured. Prevents accumulation and dripping. Thereby, when manufacturing a virtual image display device, the accuracy of assembly with other optical members is not deteriorated, and the light guide performance in the light guide device can be maintained in a good state.

  In a specific aspect of the present invention, the second step includes a dip treatment step of applying a hard coat layer coating solution by dip treatment. In this case, even if the shape of the light guide portion of the manufactured light guide device is relatively complicated, a film having a desired thickness can be uniformly formed on the light guide surface.

  In another aspect of the present invention, the dipping process includes a pulling process for pulling up the base material to be a light guide device attached to the coating liquid tank so that the flow path of the coating liquid is tilted by the flow control structure. In this case, excess coating liquid can be efficiently removed in the pulling process.

It is a perspective view which shows the virtual image display apparatus of 1st 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 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 CC cross section 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 state which prepared the process layer which filled the base material which should become a light guide device, and the coating liquid among the film-forming processes of a hard-coat layer, (B) is a process tank. (C) is a figure which shows the operation | movement which pulls up a base material from a processing tank. (A) is the perspective view which expanded a part of light transmission member, (B) is the perspective view which expanded a part of the state which joined the light guide member and the light transmission member. (A) is the perspective view which expanded a part of light transmission member of a comparative example, (B) is a figure which shows an example after the dip process of a comparative example. (A) is a perspective view of a light guide device, and (B) is a side sectional view of a base material to be a light guide device. (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 sectional drawing which shows the virtual image display apparatus which concerns on 2nd Embodiment, (B) and (C) are the front views of a light guide device, and the top view of a light guide member. It is a schematic diagram explaining the optical path of image light. It is sectional drawing explaining the junction part containing a half mirror layer. (A) is sectional drawing which shows the virtual image display apparatus which concerns on 3rd Embodiment, (B) and (C) are the front views of a light guide device, and the top view of a light guide member. It is a schematic diagram explaining the optical path of image light. It is sectional drawing explaining the junction part containing a half mirror layer. It is a figure which shows the modification of the 1st display apparatus which comprises a virtual image display apparatus.

[First Embodiment]
Hereinafter, a virtual image display device according to a first embodiment of the present invention will be described in detail with reference to the drawings.

[A. Appearance of virtual image display device)
The virtual image display device 100 according to the first 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. In addition, it is possible to make the observer observe the outside world image with see-through. The virtual image display device 100 is added to an optical panel 110 that covers the eyes of the observer, a frame 121 that supports the optical panel 110, and a portion of the frame 121 that extends from a front cover portion to a rear vine portion (temple). First and second driving units 131 and 132 are provided. 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 FIGS. 2A and 2B, the first display device 100 </ b> A 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 illumination device 31 of the image display device 11 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. Have 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.

  In the liquid crystal display device 32 described above, the first direction D1 is a longitudinal section including the first optical axis AX1 passing through the projection optical system 12 and a specific line parallel to the third reflecting surface 21c of the light guide member 21 described later. The second direction D2 corresponds to the extending direction, and the second direction D2 corresponds to the extending direction of the transverse section including the first optical axis AX1 and the normal line of the third reflecting surface 21c. 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 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.

  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. The light guide member 21 and the light transmission member 23 have a hard coat layer CC on the surface.

  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 that is a light guide surface as a first surface to a fourth surface constituting the side surface. The second reflecting surface 21b, the third reflecting surface 21c, and the fourth reflecting surface 21d. The light guide member 21 includes an upper surface 21e and a lower surface 21f that are adjacent to the first, second, third, and fourth reflecting surfaces 21a, 21b, 21c, and 21d and that face each other. 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. More specifically, the light guide member 21 is a block-shaped member integrally formed by injection molding as a resin main body portion 21s, and a mirror layer, a half mirror layer, or the like is applied thereto. The main body portion 21s is formed, for example, by injecting a heat or photopolymerization type resin material into a molding die and thermosetting or photocuring. Thus, although the light guide member 21 has the main body portion 21s as an integrally formed product, it can be functionally divided into the light incident part B1, the light guide part B2, and the 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 25 is formed by forming a film by vapor deposition of aluminum or the like on the slope RS of the main body portion 21 s 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 reflection coating such as a mirror layer, but are hard surfaces that are surface coating layers on the surface of the main body portion 21s. It is formed by forming a coat layer CC. The hard coat layer CC is formed on the exposed portion of the virtual image display device 100, and forms the first and second reflecting surfaces 21a and 21b, and prevents the exposed portion from being damaged and facilitates the removal of dirt. To prevent a decrease in the resolution of the video.

  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. The half mirror layer 28 is provided in a rectangular partial region disposed at the center of the fourth reflecting surface 21d. 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 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.

  The light transmission member 23 includes a main body portion 23s having the same refractive index as the main body portion 21s of the light guide member 21, and includes a first surface 23a, a second surface 23b, and a third surface 23c. The first and second surfaces 23a and 23b are formed by forming a hard coat layer CC as a surface coat layer on the surface of the main body portion 23s, similarly to the first and second reflection surfaces 21a and 21b. , Extending 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-shaped member integrally formed by injection molding as a main body portion 23s. The main body portion 23s is formed by, for example, injecting heat or a photopolymerization type resin material into a molding die. It is formed by thermosetting or photocuring.

  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. However, since the fourth reflecting surface 21d of the light guide member 21 includes the half mirror layer 28, the center of the third surface 23c. The external light GL ′ passing through the region is attenuated 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%.

  As shown in FIGS. 3A to 3D, the light guide member 21 is a trapezoidal prism-like member in plan view, and the light transmitting member 23 is shown in FIGS. 4A to 4D. Thus, it has a U-shaped appearance and is capable of fitting the light guide member 21, and a pair of left and right light guide members 21 for the left eye and the light guide member 21 for the right eye, respectively. The light transmitting members 23, 23 are integrated to form an H-shaped support frame 123 in a front view. The central member 24a of the support frame 123 is formed with a cutout 24x for fitting a nose pad.

  The light guide member 21 shown in FIG. 3A or the like is fitted to the support frame 123 shown in FIG. The support member 24b and the lower support member 24c are joined and fixed so as to be sandwiched between them. Thereby, for example, the state shown in FIG. 2B is obtained, and the optical panel 110 of FIG. 1 is manufactured as a whole.

  As shown in FIG. 2B, the first connecting portion 24e provided at the distal end portion of the upper support member 24b and the second connecting portion 24f provided at the distal end portion of the lower support member 24c have a three-dimensional shape. It has holes H1, H2, and H3, respectively. Optical components such as the projection optical system 12 are assembled in the holes H1 and the like with screws (not shown). That is, the holes H1, H2, and H3 function as, for example, a fastening portion when the image forming apparatus 10 is assembled to the light guide device 20, and the position of the light incident surface IS in the light incident portion B1 included in the light guide device 20 It functions as a positioning unit that performs relative positioning with the projection optical system 12 included in the image forming apparatus 10. Here, in particular, as shown in FIG. 4A and the like, grooves CT1, CT2, and CT3 formed by cutting out part of the side surfaces of the holes H1 to H3 around the holes H1, H2, and H3, respectively. By being provided, the liquid pool preventing structure CS is formed. As will be described in detail later, the liquid pool prevention structure CS is a coating liquid that is a raw material for the hard coat layer CC in order to make the film formation state of the hard coat layer CC appropriate without local spots due to excessive thickness. It functions as a flow control structure FS that controls the flow of the coating liquid and suppresses the occurrence of coat spots when applied.

  Returning to FIG. 2B, the liquid dripping prevention structure DS is formed by providing a step at the boundary between the light guide member 21 and the light transmission member 23. As will be described in detail later, the liquid dripping prevention structure DS is a coating used as a raw material for the hard coat layer CC in order to make the film formation state of the hard coat layer CC appropriate without local spots due to excessive or insufficient thickness. When the liquid is applied, it functions as a flow control structure FS that controls the flow of the coating liquid to suppress the occurrence of coating spots.

  In the virtual image display device 100 having the see-through configuration as described above, since the exposed portion through which light is transmitted increases, a hard coat for keeping the see-through in a good state on the surface of the light guide member 21 or the light transmitting member 23. It is more important to provide the layer CC. On the other hand, the light guide member 21 and the light transmission member 23 constituting the light guide device 20 have a relatively complicated shape having a large number of surface portions as described above, and the surface of the light guide device 20 has a desired surface. It is not always easy to form a film with a uniform hard coat layer CC. From the above, it is desirable that the hard coat layer CC provided in the light guide device 20 is formed by, for example, dip processing. Here, the dipping process is to fill a coating liquid, which is a raw material of the hard coat layer CC, in a tank of a certain size, immerse the entire base material to be the light guide device 20 in the tank, and then the base material The film is formed by slowly pulling up the film. By forming the hard coat layer CC by this dipping process, even if the shape is complicated such as the light guide device 20 having a plurality of surface portions, the substrate is rotated at high speed and centrifugal force is used. Compared with methods such as spin coating for film formation and bar coating for film formation by brushing, a uniform film with few spots can be formed on each surface portion of the substrate. However, since the dipping process is performed by immersing the entire base material in the coating liquid as described above and then pulling it up, for example, a liquid pool is generated in a fine part of the base material such as the hole H1 of the connecting portions 24e and 24f. Or dripping may occur near the boundary between the surfaces of the substrate. In the present embodiment, in order to prevent such a situation, for example, a groove CT1 or the like that is a relief groove is provided in a hole H1 or the like that is liable to generate a liquid pool. That is, the groove CT1 or the like constitutes a liquid pool prevention structure CS that prevents liquid pool by promoting the flow of excess coating liquid. In other words, the liquid pool prevention structure CS is a flow control structure FS for controlling the flow of the coating liquid. In addition, a step is provided at the boundary between the light guide member 21 and the light transmission member 23 to form a liquid dripping prevention structure DS that prevents excess coating liquid from being damped and prevents liquid dripping. In other words, the dripping prevention structure DS is a flow control structure FS that controls the flow of the coating liquid.

[C. Formation of hard coat layer)
Hereinafter, an example of a process for forming the hard coat layer CC in the manufacturing process of the virtual image display device 100 will be briefly described. Here, as described above, the hard coat layer CC is formed by dipping. 5 (A) to 5 (C) are diagrams schematically showing a film forming process of the hard coat layer CC. First, as shown in FIG. 5A, a base material PA to be a light guide device 20 in which a base material portion PB to be the light guide member 21 and a base material portion PC to be the light transmission member 23 are joined. In addition to preparation (flow control structure preparation step; first step), a treatment tank DT filled with the coating liquid CL is prepared (treatment layer preparation step). As shown in FIGS. 5A to 5C, the base material portion PC of the base material PA has a liquid pool prevention structure CS, that is, a flow control structure FS. Further, a dripping prevention structure DS, that is, a flow control structure FS is formed at the boundary between the base material portion PB and the base material portion PC. Next, as shown in FIG. 5B, the prepared base material PA is immersed in the treatment tank DT (dip treatment step), and the coating liquid CL is sufficiently spread over the entire surface of the base material PA. As shown to (C), base material PA is pulled up from the processing tank DT (pull-up process). For example, in the pulling-up process, the excess coating liquid CL can be obtained by pulling up the base material PA so that the flow path (see FIG. 4A) of the coating liquid CL formed by extending the relief grooves such as the grooves CT1 is inclined. And the coating liquid CL can be applied thinly and uniformly. Finally, the hard coat layer CC is formed by curing the coating liquid CL applied to the surface of the pulled-up base material PA (hard coat layer forming step; second step). The film thickness of the hard coat layer CC formed as described above is preferably about 5 μm. Thereby, the shape of the light guide device 20 after the hard coat layer CC is formed maintains the shape before the film formation, and the hard coat layer CC is prevented from being damaged and dirt can be easily removed. It has a thickness that can function as a hard coat.

  In the example shown in FIGS. 5 (A) to 5 (C), the base member PB to be the light guide member 21 and the base member portion PC to be the light transmitting member 23 are assembled. Although the material PA is formed, the hard coat layer CC can be formed separately for each of the base material portion PB and the base material portion PC.

[D. (Puddle prevention structure)
Hereinafter, as an example of the flow control structure FS for controlling the flow of excess coating liquid when forming the hard coat layer CC, a liquid pool prevention structure CS provided in the virtual image display device 100 will be described in detail.

  FIG. 6A is an enlarged perspective view showing a portion of the light transmitting member 23 that constitutes the liquid pool preventing structure CS provided in the connecting portion 24e, and shows a broken line region LU in FIG. 4A. Corresponds to the part. FIG. 6B is an enlarged perspective view showing a part of the light guide device 20 in which the light guide member 21 and the light transmission member 23 are joined. As described above, escape holes such as the grooves CT1 and CT2 are provided in the holes H1 to H3 that are cut out in a circular shape in the connecting portion 24e so as to constitute the liquid pool preventing structure CS. For example, the hole H1 is a concave portion that is counterbored to embed a screw structure for assembling an optical component such as the light guide member 21, and the groove CT1 is formed by cutting out a part of the side surface of the hole H1. . That is, the groove CT1 is a one-side empty counterbore part or a counterbore notch part. Although detailed illustration and description are omitted, the hole H3 and the groove CT3 provided in the male part of the hole H3 (see FIG. 4 (A)) were also subjected to counterboring similarly to the hole H1 and the groove CT1. It has a structure with a concave portion and a cutout portion formed by cutting out a part of the concave portion. The groove CT1 extends in the Y direction along the non-confining direction DW1 (see FIG. 2B, etc.) and allows the coating liquid CL to flow toward the outside of the light guide portion. In the dipping process (see FIG. 5B), the excess portion of the coating liquid CL filling the hole H1 extends in the groove CT1 which is the direction of the flow path during the pulling-up process (see FIG. 5C). By tilting along the direction, the groove CT1 flows out, so that only the necessary amount of the hard coat layer CC remains on the surface, and the remaining components are cured. The same applies to the other holes H2 and H3 provided in the connecting portion 24e. As described above, in the present embodiment, in the dipping process, even if the inside of the holes H1 to H3 is filled with the coating liquid CL that is the raw material of the hard coat layer CC, the groove is formed during the pulling process of pulling up from the coating liquid CL. Excess coating liquid CL is removed by CT1 and the like functioning as a liquid pool preventing structure CS that prevents liquid pooling. On the other hand, when the hole H1 or the like as a positioning member does not have the groove CT1 or the like as shown in FIG. 7A as a comparative example of the one having the hole H1 and the hole H3, The excess coating liquid CL that has entered the shaped hole H1 is hardened in a state where it is accumulated due to surface tension or the like, and closes or deforms the holes H1 and H3 as shown in FIG. As a result, it may become impossible to function as a positioning portion. In the present embodiment, such a situation can be avoided by suppressing the surface tension and forming an escape path for excess coating liquid CL by the liquid pool prevention structure CS.

  Further, as shown in FIG. 6B, when a hard coat film is formed on the base material PA to be the light guide device 20 in which the light guide member 21 and the light transmitting member 23 are joined, the hole H2 is provided. The flow path of the coating liquid CL formed by the groove CT <b> 2 is directed toward the flat surface FF that is one surface of the light guide member 21. The flat surface FF corresponds to part of the upper surface 21e and the lower surface 21f (see FIG. 3A) of the light guide member 21. In this case, the excess coating liquid CL that flows out from the hole H2 through the groove CT2 flows out to the flat surface FF side, so that the excessive coating liquid CL accumulates on the flat surface FF, and the hard coat is somewhat thicker than the other portions. A layer CC may be formed. However, the flat surface FF is not a light guiding surface that contributes to light guiding, such as the reflecting surface 21b or the reflecting surface 21c, and is a portion hidden by the frame 121 in the completed state of the virtual image display device 100 shown in FIG. It is not an external appearance part exposed to the outside. Therefore, even if the hard coat layer CC of the flat surface FF is somewhat thick, it does not affect the optical function or appearance. In the present embodiment, as shown in the above-described groove CT2, etc., in the liquid pool prevention structure CS, that is, the flow control structure FS, the excess coating liquid CL is obtained by adjusting the flow path and directing the coating liquid toward the flat surface FF. Is avoiding heading to the light guide surface and the outer appearance.

[E. (Drip prevention structure)
Hereinafter, a liquid dripping prevention structure DS provided in the virtual image display device 100 will be described in detail as another example of the flow control structure FS that controls the flow of excess coating liquid when forming the hard coat layer CC.

  8A is a perspective view showing the entire light guide device 20 in which the light guide member 21 and the light transmission member 23 are joined, and FIG. 8B is a light guide device shown in FIG. 8A. It is a side view which shows the state before the hard-coat film-forming of base material PA which should become 20. Of the base material PA shown in FIG. 8B, for example, unnecessary coating liquid is temporarily generated around the boundary between the base material portion PB to be the light guide member 21 and the base material portion PC to be the light transmission member 23. If liquid dripping occurs on the surface SFb to be the second reflecting surface 21b, which is one of the light guide surfaces of the light guide member 21, due to the accumulated coating liquid, the flatness of the second reflecting surface 21b is impaired and desired. In this state, the light cannot be guided and the image may be disturbed. On the other hand, in this embodiment, the surface SFb to be the second reflecting surface 21b of the light guide member 21 is in the + Z direction with respect to the surface SS to be the second surface 23b of the adjacent light transmitting member 23. Protruding. In other words, both the non-confinement direction DW1 and the confinement direction DW2 (see FIG. 2B, etc.) at the boundary between the base material portion PB to be the light guide member 21 and the base material portion PC to be the light transmission member 23. The liquid dripping prevention structure DS is formed by providing the stepped portion BU extending along the direction perpendicular to the X direction (X direction). Due to such a liquid dripping prevention structure DS by the stepped portion BU, for example, the coating liquid CL is dammed in the vicinity of the boundary between the base material portion PB and the base material portion PC. In particular, the stepped portion BU flows the coating liquid CL along the X direction perpendicular to both the direction DW1 and the direction DW2, which is the traveling direction of the entire image light, and therefore faces the surface SFb side, that is, the second reflecting surface 21b side. Can be eliminated without dripping. As described above, in the light guide device 20, the step liquid dripping prevention structure DS, that is, the flow control structure FS is configured. Such a situation is avoided that an inadvertent dripping of the coating liquid impairs the flatness of the second reflecting surface 21b, which is the light guide surface, and deteriorates the optical function.

  In the above description, if the difference d between the surface SFb and the surface SS in the + Z direction is, for example, about 0.5 mm, the width is sufficiently larger than the target thickness of the hard coat layer CC, which is about 5 μm. The liquid CL can be dammed, and the stepped portion BU functions sufficiently as a liquid dripping prevention structure DS for preventing liquid dripping.

[F. Overview of optical path of image light)
Hereinafter, an outline of an optical path of image light in the virtual image display device 100 will be described.

  FIG. 9A illustrates the 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. 9B is a diagram illustrating an optical path in the second direction D2 corresponding to the cross section CS2 of the liquid crystal display device 32. FIG. In the cross section CS2 along the second direction D2, that is, the XZ plane (the unfolded X′Z ′ plane), of the image light emitted from the liquid crystal display device 32, toward the display region 32b indicated by the alternate long and short dash line in the figure. The component emitted from the first display point P1 on the right end side (+ X side) is the image light GL1, and from the second display point P2 on the left end side (−X side) toward the display region 32b indicated by the two-dot chain line in the drawing. Let the emitted component be image light GL2.

The image light GL1 from the first display point P1 on the right side is converted into a parallel 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 GL2 from the second display point P2 on the left side is converted into a parallel light flux 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 lateral direction of the second direction D2 or the confinement direction DW2, the image light GL1 and GL2 are folded back by reflection in the light guide member 21, and the number of reflections is different. It is expressed discontinuously in the member 21. 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. Incidentally, considering that the number of reflections light guide member within 21 of both the image light GL1, GL2 are different from each other, the exit angle theta ₁ of the right side of the image light GL1 _'the exit angle theta ₂ of the left side of the image light GL2' Is set to something different.

  As described above, the image lights GLa, GLb, GL1, and GL2 incident on the observer's eye EY are virtual images from infinity, and the liquid crystal display device 32 has the vertical first direction D1 or the unconfined direction DW1. The formed image is upright, and the image formed on the liquid crystal display device 32 is reversed with respect to the second horizontal direction D2 or the confinement direction DW2.

[G. (The optical path of image light in the horizontal direction)
FIG. 10 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. 10, when the light guide member 21 is developed, the virtual first surface 121a corresponding to the first reflection surface 21a and when the light guide member 21 is deployed, the virtual surface 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. 11A is a diagram conceptually illustrating a display surface of the liquid crystal display device 32, and FIG. 11B is a diagram conceptually illustrating a virtual image of the liquid crystal display device 32 that can be seen by an observer. 11 (C) and 11 (D) 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. 11A 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. 11A 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.

  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 CC, and may be generated on the surface side of the hard coat layer CC. It can also be made. When total reflection is caused on the surface side of the hard coat layer CC, it is particularly important to prevent the liquid dripping described above.

  As described above, in the present embodiment, the light guide device 20 is provided at the boundary between the light guide member 21 and the light transmitting member 23 or the liquid pool preventing structure constituted by the grooves CT1, CT2, and CT3 which are escape grooves. The liquid dripping prevention structure comprised by the level | step-difference part BU formed is provided as a flow control structure. Thereby, in the film formation of the hard coat layer, the flow of the coating liquid as a raw material is appropriately controlled, and the liquid pool and dripping due to the coating liquid CL can be prevented from occurring at an unintended portion of the light guide device 20. Therefore, it is possible to maintain the light guide performance in the light guide device 20 in a good state without deteriorating the accuracy of assembly of the optical components constituting the virtual image display device 100.

[Second Embodiment]
The virtual image display device according to the second embodiment will be described below. The virtual image display device according to the present embodiment is a modification of the virtual image display device 100 according to the first embodiment, and is the same as the first virtual image display device 100 unless otherwise described.

  A virtual image display device 100 illustrated in FIGS. 12A to 12C includes the image forming apparatus 10 and a light guide device 420 as a set. The light guide device 420 includes the light guide member 21, an angle conversion unit 423, and a support member 429. Note that FIG. 12A corresponds to a cross section taken along line AA of the light guide device 420 illustrated in FIG.

  The overall appearance of the light guide member 21 is formed by a main body portion 21s which is a flat plate extending parallel to the XY plane in the drawing. The light guide member 21 includes, as side surfaces, a first reflecting surface 21a, a second reflecting surface 21b, a third reflecting surface 21c, and a first joining surface 21j. The light guide member 21 has an upper surface 21e and a lower surface 21f that are adjacent to the first, second, and third reflecting surfaces 21a, 21b, and 21c and that face each other. Furthermore, the light guide member 21 has a prism portion PS formed so as to expand the main body portion 21s at one end in the longitudinal direction and a third reflecting surface 21c associated therewith, and a plurality of mirrors at the other end in the longitudinal direction. It is the structure connected to the angle conversion part 423 comprised by these.

  The main body portion 21s is formed of a light-transmitting resin material or the like, and has a light incident surface IS that takes in the image light from the image forming apparatus 10 on a back surface parallel to the XY plane and facing the image forming apparatus 10. doing. The main body portion 21 s has a rectangular inclined surface RS in addition to the light incident surface IS as a side surface of the prism portion PS, and a mirror layer 25 is formed on the inclined surface RS so as to cover it. Here, the mirror layer 25 functions as the third reflecting surface 21c arranged in an inclined state with respect to the light incident surface IS by cooperating with the inclined surface RS. The third reflecting surface 21c folds the image light that is incident from the light incident surface IS and travels in the + Z direction as a whole so as to be directed in the −X direction that is biased in the −Z direction as a whole. Securely bond within 21s.

  The first and second reflecting surfaces 21a and 21b of the light guide member 21 are the main surfaces of the plate-shaped main body portion 21s and are bent by the prism portion PS as two planes facing each other and extending parallel to the XY plane. Each image light is totally reflected. The image light reflected by the third reflecting surface 21c first enters the first reflecting surface 21a and is totally reflected. Next, the image light enters the second reflecting surface 21b and is totally reflected. Hereinafter, by repeating this operation, the image light is guided to the back side of the light guide member 21, that is, the −X side where the angle conversion unit 423 is provided.

  As shown in FIG. 12C, in the light guide member 21, the third reflecting surface 21c and a light incident surface IS described later function as a light incident part B1. Further, the main body portion 21s sandwiched between the first and second reflecting surfaces 21a and 21b of the light guide member 21 and an angle conversion unit 423 described later function as the light guide unit B2. The angle conversion unit 423 functions as the light emission unit B3.

  The angle conversion part 423 is formed along the extended plane of the first and second reflecting surfaces 21a and 21b on the back side (−X side) of the light guide member 21. Here, the back end of the main body portion 21 s is a part of the angle conversion unit 423. The angle conversion unit 423 includes a large number of half mirror layers 28 that are inclined with respect to the first and second reflecting surfaces 21a and 21b and arranged in parallel to each other at equal intervals. The angle conversion unit 423 reflects the image light that has entered through the first and second reflecting surfaces 21a and 21b of the light guide member 421 at a predetermined angle, and passes through the light exit surface OS to the observer's eye EY side. Bend it. That is, the angle conversion unit 423 converts the angle of the image light.

  The light transmitting member 23 s is a portion obtained by extending the angle conversion portion 423 to the back side (−X side), and is a flat plate-like member like the main body portion 21 s of the light guide member 421.

  In the above, the whole angle conversion part 423 or a part on the entrance side also functions as a part of the light guide part B2 by being combined with the light guide member 21. Further, all or a part of the back side of the angle conversion unit 423 functions as a see-through unit by being combined with the light transmission member 23s.

  As shown in FIG. 12B, the support member 429 is a support frame (not shown) located on the back side (−X side) of the angle conversion unit 423 and the light transmission member 23s in order to support the light guide member 21. Each of which includes an upper support member 24b and a lower support member 24c extending in the X direction, and is fixed so as to sandwich the light guide member 21 and the angle conversion portion 423. Furthermore, the support member 429 includes a first connection portion 24e provided at the distal end portion of the upper support member 24b and a second connection portion 24f provided at the distal end portion of the lower support member 24c. The connecting portions 24e and 24f are provided with a liquid pool preventing structure CS as the flow control structure FS. In addition, a dripping prevention structure DS is provided at the boundary between the support member 529 and the light guide member 521.

  The image light emitted from the image forming apparatus 10 and incident on the light guide member 21 from the light incident surface IS is uniformly reflected and bent by the third reflection surface 21c, and the first and second reflection surfaces of the light guide member 21 are reflected. 21a and 21b are repeatedly totally reflected and proceed in a state of having a certain spread substantially along the optical axis AX. Further, the angle conversion unit 423 is bent at an appropriate angle so that it can be taken out. The light exits from the light exit surface OS attached to the conversion unit 423. The image light emitted to the outside from the light exit surface OS enters the observer's eye EY as virtual image light.

  Hereinafter, the optical path of the image light in the light guide device 420 will be described. In addition, the light guide apparatus 420 in 2nd Embodiment functions similarly to the light guide apparatus 20 of FIG. 1 (A) regarding the vertical 1st direction D1 (Y direction). On the other hand, the light guide device 420 guides a plurality of propagation mode image lights in the second horizontal direction D2 (X direction), and guides the two propagation mode image lights. This is different from the light guide device 20 in FIG.

  As shown in FIG. 12A, among the image light emitted from the liquid crystal display device (image light forming unit) 32 of the image display device 11, the component indicated by the dotted line emitted from the central portion of the emission surface 32a is an image. A component indicated by a one-dot chain line emitted from the right side (+ X side) of the emission surface 32a as the light GL41 is a component indicated by a two-dot chain line emitted from the left side (−X side) of the emission surface 32a as the image light GL42. Is image light GL43.

The main components of the image lights GL41, GL42, and GL43 that have passed through the projection optical system 12 are all incident at different angles on the first and second reflecting surfaces 21a and 21b after entering from the light incident surface IS of the light guide member 21, respectively. Repeat reflection. Specifically, among the image lights GL41, GL42, and GL43, the image light GL41 emitted from the central portion of the emission surface 32a of the liquid crystal display device (image light forming unit) 32 passes through the projection optical system 12 and then becomes a parallel beam. after being reflected by the incident third reflecting surface 21c on the light incident surface iS as, incident on the first reflecting surface 21a of the light guide member 21 with a standard reflection angle gamma _0, is totally reflected. Thereafter, the image light GL41 is, while maintaining the standard reflection angle gamma _0, the first and second reflecting surfaces 21a, repeating total reflection at 21b. The image light GL41 is totally reflected N times (N is a natural number) on the first and second reflection surfaces 21a and 21b, and reaches the central portion 23k of the angle conversion unit 423. The image light GL41 reflected by the central portion 23k is emitted as a parallel light flux in the optical axis AX direction perpendicular to the light emission surface OS or the XY plane from the light emission surface OS.

The image light GL42 emitted from one end side (+ X side) of the emission surface 32a of the liquid crystal display device 32 is incident on the light incident surface IS as a parallel beam after passing through the projection optical system 12, and is reflected by the third reflecting surface 21c. Thereafter, the light enters the first reflecting surface 21a of the light guide member 21 at the maximum reflection angle γ ₊ and is totally reflected. The image light GL42 is totally reflected, for example, NM times (M is a natural number) on the first and second reflecting surfaces 21a and 21b, and reaches the peripheral portion 23m on the most entrance side (+ X side) of the angle conversion portion 423. The image light GL42 reflected by the peripheral portion 23m forms an obtuse angle with respect to the + X axis so as to be away from the entrance third reflecting surface 21c side, and an angle θ ₁₂ (within the light guide device 420) with respect to the optical axis AX. Injected in a direction inclined by θ ₁₂ ′) (see FIG. 13).

The image light GL43 emitted from the other end side (−X side) of the emission surface 32a of the liquid crystal display device 32 is incident on the light incident surface IS as a parallel light flux after passing through the projection optical system 12, and is reflected by the third reflecting surface 21c. After that, the light enters the first reflecting surface 21a of the light guide member 21 at the minimum reflection angle γ ₋ and is totally reflected. The image light GL43 is totally reflected, for example, N + M times on the first and second reflecting surfaces 21a and 21b, and enters the peripheral portion 23h on the farthest side (−X side) of the angle conversion portion 423. The image light GL43 reflected by the peripheral portion 23h makes an acute angle with respect to the + X axis so as to be returned to the third reflecting surface 21c side, and has an angle θ ₁₃ (θ within the light guide device 420) with respect to the optical axis AX. It is injected in a direction inclined by ₁₃ ′) (see FIG. 13).

  As shown in FIG. 14, the angle conversion unit 423 has a structure in which a plurality of prisms 424 are arranged in the X direction at a predetermined pitch. Each prism 424 has a first joint surface 424j on the light exit side and a second joint surface 424c on the light incident side. On the first joint surface 21j of the main body portion 21s or the first joint surface 424j of each prism 424, a half mirror layer 28 that is a semi-transmissive reflective film is formed on a local partial region.

  Also in the virtual image display device 100 of the second embodiment, as shown in FIG. 12B, the liquid control structure FS includes a liquid pool prevention structure CS and a liquid dripping prevention structure DS. Thereby, the flow of the coating liquid is appropriately controlled when forming the hard coat layer, the accuracy of assembling of each optical component is not deteriorated, and the light guide performance in the light guide device 420 is good. Can be maintained.

[Third Embodiment]
The virtual image display device according to the third embodiment will be described below. The virtual image display device according to the present embodiment is a modification of the virtual image display device 100 according to the first embodiment, and is the same as the first virtual image display device 100 unless otherwise described.

  A virtual image display device 100 illustrated in FIGS. 15A to 15C includes the image forming device 10 and a light guide device 520 as a set. The light guide device 520 includes a light guide member 21, an angle conversion unit 523, and a support member 529. The light guide member 521 includes a main body portion 21s and an angle conversion unit 523 which is an image extraction unit. Note that FIG. 15A corresponds to the AA cross section of the light guide member 521 shown in FIG.

  The overall appearance of the light guide member 521 is formed by a main body portion 21s which is a flat plate extending parallel to the XY plane in the drawing. Moreover, the light guide member 521 has the 1st reflective surface 21a, the 2nd reflective surface 21b, and the 3rd reflective surface 21c as a side surface. The light guide member 521 has an upper surface 21e and a lower surface 21f that are adjacent to the first, second, and third reflecting surfaces 21a, 21b, and 21c and that face each other. Furthermore, the light guide member 521 has a prism portion PS formed so as to expand the main body portion 21s at one end in the longitudinal direction and a third reflecting surface 21c associated therewith, and the main body portion 21s at the other end in the longitudinal direction. It has the structure which has the angle conversion part 523 comprised by many micromirrors embedded in. Although the light guide member 521 is an integral part, it can be divided into the light incident part B1, the light guide part B2, and the light emission part B3 as in the case of the first embodiment (FIG. 15 ( Among them, the light incident part B1 is a part having a third reflecting surface 21c and a light incident surface IS described later, and the light incident part B1 has first and second reflecting surfaces 21a, 21b. The light guide part B2 is a part having an angle conversion part 523 and a light exit surface OS described later.

  The main body portion 21s is formed of a light-transmitting resin material or the like, and receives light that captures image light from the image forming apparatus 10 on a back surface or an observer-side plane that is parallel to the XY plane and faces the image forming apparatus 10. It has a surface IS and a light emission surface OS that emits image light toward the eye EY of the observer. The main body portion 21 s has a rectangular inclined surface RS in addition to the light incident surface IS as a side surface of the prism portion PS, and a mirror layer 25 is formed on the inclined surface RS so as to cover it. Here, the mirror layer 25 functions as the third reflection surface 21c which is an incident light bending portion arranged in an inclined state with respect to the light incident surface IS by cooperating with the inclined surface RS. The third reflecting surface 21c folds the image light that is incident from the light incident surface IS and travels in the + Z direction as a whole so that the image light is directed in the −XZ direction that is biased in the −Z direction as a whole. Securely bond within 21s. Further, in the main body portion 21s, an angle conversion portion 523 having a fine structure is formed along the plane on the back side of the light emission surface OS. The main body portion 21s extends from the third reflection surface 21c on the entrance side to the angle conversion unit 523 on the back side, and guides image light incident inside through the prism unit PS to the angle conversion unit 523.

  The first and second reflecting surfaces 21a and 21b of the light guide member 521 are the main surfaces of the plate-shaped main body portion 21s, and are two planes facing each other and extending in parallel to the XY plane. Each of the image lights bent at B1 is totally reflected. The image light reflected by the third reflecting surface 21c first enters the first reflecting surface 21a and is totally reflected. Next, the image light enters the second reflecting surface 21b and is totally reflected. Hereinafter, by repeating this operation, the image light is guided to the back side of the light guide device 520, that is, the −X side where the angle conversion unit 523 is provided.

  The angle conversion unit 523 arranged to face the light exit surface OS of the main body portion 21s is on the extended plane along the extended plane of the second reflecting surface 21b on the back side (−X side) of the light guide member 521. It is formed in close proximity. The angle conversion unit 523 reflects the image light incident through the first and second reflection surfaces 21a and 21b of the light guide member 521 at a predetermined angle and bends the light toward the light exit surface OS. That is, the angle conversion unit 523 converts the angle of the image light.

  As shown in FIG. 15B, the support member 529 is a part of a support frame (not shown) located on the back side (−X side) of the angle conversion unit 523 in order to support the light guide member 21. The upper support member 24b and the lower support member 24c extend in the X direction, and are fixed so as to sandwich the light guide member 521 and the angle conversion unit 523 therebetween. Further, the support member 529 includes a first connection portion 24e provided at the distal end portion of the upper support member 24b and a second connection portion 24f provided at the distal end portion of the lower support member 24c. The connecting portions 24e and 24f are provided with a liquid pool preventing structure CS as the flow control structure FS. Further, a dripping prevention structure DS is provided at a boundary between the support member 529 and the light guide member 521 or the like.

  The image light emitted from the image forming apparatus 10 and incident on the light guide member 521 from the light incident surface IS is uniformly reflected and bent by the third reflection surface 21c, and the first and second reflection surfaces of the light guide member 521 are bent. 21a and 21b are repeatedly totally reflected and proceed in a state of having a certain spread substantially along the optical axis AX. Further, the angle conversion unit 523 is bent at an appropriate angle so that it can be taken out. Injected outside from the exit surface OS. The image light emitted to the outside from the light exit surface OS enters the observer's eye EY as virtual image light. By forming the virtual image light on the retina of the observer, the observer can recognize image light such as video light by the virtual image.

  Hereinafter, the optical path of the image light in the light guide device 520 will be described. Note that the light guide device 520 in the third embodiment functions in the same manner as the light guide device 20 in FIG. 1A with respect to the vertical first direction D1 (Y direction). On the other hand, the light guide device 520 guides a large number of propagation mode image lights in the second horizontal direction D2 (X direction), and guides the two propagation mode image lights. This is different from the light guide device 20 in FIG.

  As shown in FIG. 15A, among the image light emitted from the liquid crystal display device (image light forming unit) 32 of the image display device 11, the component indicated by the dotted line emitted from the central portion of the emission surface 32a is an image. The component indicated by the alternate long and short dash line emitted from the right side (+ X side) of the emission surface 32a as the light GL51 is set as the image light GL52, and the component indicated by the two-dot chain line emitted from the left side (−X side) of the emission surface 32a. Is image light GL53.

The main components of the image lights GL51, GL52, and GL53 that have passed through the projection optical system 12 are all incident at different angles on the first and second reflecting surfaces 21a and 21b after entering from the light incident surface IS of the light guide member 521, respectively. Repeat reflection. Specifically, among the image lights GL51, GL52, and GL53, the image light GL51 emitted from the central portion of the emission surface 32a of the liquid crystal display device (image light forming unit) 32 passes through the projection optical system 12 and then becomes a parallel beam. After being incident on the light incident surface IS and reflected by the third reflecting surface 21c, the light is incident on the first reflecting surface 21a of the light guide member 521 at the standard reflection angle γ ₀ and totally reflected. Thereafter, the image light GL51 is, while maintaining the standard reflection angle gamma _0, the first and second reflecting surfaces 21a, repeating total reflection at 21b. The image light GL51 is totally reflected N times (N is a natural number) on the first and second reflection surfaces 21a and 21b, and reaches the central portion 23k of the angle conversion unit 523. The image light GL51 reflected by the central portion 23k is emitted from the light exit surface OS as a parallel light flux in the optical axis AX direction perpendicular to the light exit surface OS or the XY plane.

The image light GL52 emitted from one end side (+ X side) of the emission surface 32a of the liquid crystal display device 32 enters the light incident surface IS as a parallel light flux after passing through the projection optical system 12, and is reflected by the third reflecting surface 21c. Thereafter, the light enters the first reflection surface 21a of the light guide member 521 at the minimum reflection angle γ ₊ and is totally reflected. The image light GL52 is totally reflected, for example, NM times (M is a natural number) on the first and second reflection surfaces 21a and 21b, and reaches the peripheral portion 23h on the farthest side (−X side) of the angle conversion portion 523. . The image light GL52 reflected by the peripheral portion 23h forms an acute angle with respect to the + X axis so as to return to the third reflecting surface 21c side of the entrance, and an angle θ ₁₂ (within the light guide device 520 with respect to the optical axis AX). Then, it is injected in a direction inclined by θ ₁₂ ′) (see FIG. 16).

The image light GL53 emitted from the other end side (−X side) of the emission surface 32a of the liquid crystal display device 32 enters the light incident surface IS as a parallel light flux after passing through the projection optical system 12, and is reflected by the third reflecting surface 21c. After that, the light enters the first reflecting surface 21a of the light guide member 521 at the minimum reflection angle γ ₋ and is totally reflected. The image light GL53 is totally reflected, for example, N + M times on the first and second reflecting surfaces 21a and 21b, and enters the peripheral portion 23m on the most entrance side (+ X side) of the angle conversion unit 523. Image light GL53 was a reflection at the peripheral portion 23m, a third obtuse angle with respect to As + X-axis away from the reflecting surface 21c side, the angle theta ₁₃ (light guide device within 520 with respect to the optical axis AX theta ₁₃ Injected in a direction inclined by ') (see FIG. 16).

  In addition, as shown in FIG. 16, the angle conversion part 523 is comprised with many linear reflection units 2c arranged in stripe form. In other words, the angle conversion unit 523 is configured by arranging a number of elongated reflection units 2c extending in the Y direction along the main light direction, that is, the −X direction, in which the angle conversion unit 523 extends at a predetermined pitch PT. Each reflection unit 2c is a first reflection surface 2a that is one reflection surface portion disposed on the back side, that is, the optical path downstream side, and another one reflection surface portion that is disposed on the entrance side, that is, the optical path upstream side. The second reflecting surface 2b is provided as a set, and both reflecting surfaces 2a and 2b form a constant wedge angle δ. Among these, at least the second reflecting surface 2b is a partially reflecting surface that can transmit a part of light, and allows an observer to observe an external image in a see-through manner. In the reflection unit 2c, the image lights GL52 and 53 are first reflected by the first reflection surface 2a on the back side, that is, the −X side, and then reflected by the second reflection surface 2b on the entrance side, that is, the + X side. The The image light GLs 52 and 53 that have passed through the reflection unit 2c are bent to a desired angle and taken out to the viewer side by passing through the angle conversion unit 523 only once without passing through the other reflection unit 2c.

  As shown in FIG. 17, the angle conversion part 523 has a structure in which a relatively thick plate-shaped joining member 521n extending from the light guide member 521 and a relatively thin plate-shaped joining member 523n extending from the light transmitting member 23s are joined. Have The bonding member 521n has a first bonding surface 21j on the front side or the outside, and the bonding member 523n has a second bonding surface 23c on the back side or the observer side. On the first bonding surface 21j of the bonding member 521n, a half mirror layer 28 that is a semi-transmissive reflection film is formed on a local partial region.

  Also in the virtual image display device 100 of the third embodiment, as shown in FIG. 15B, the liquid control structure FS includes a liquid pool prevention structure CS and a liquid dripping prevention structure DS. Accordingly, the flow of the coating liquid is appropriately controlled during the formation of the hard coat layer, the accuracy of assembling of each optical component is not deteriorated, and the light guide performance in the light guide device 520 is good. Can be maintained.

[Others]
Although the present invention has been described with reference to each embodiment, the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the spirit of the present invention. The following modifications are possible.

  For example, in the pulling up of the base material PA shown in FIG. 5C, the base material PA can be pulled up while being tilted or shaken corresponding to the flow path of the flow control structure. Specifically, for example, the surplus is more efficiently achieved by pulling up the substrate PA while tilting so that the flow path in the groove CT1 shown in FIG. The coating liquid can be removed.

  In the above-described embodiment, the flow control structure FS includes both the liquid pool prevention structure CS and the liquid dripping prevention structure DS. However, the flow control structure FS may have only one of them. For example, in FIG. 2B, the dripping prevention structure DS is provided in both the X direction and the Y direction, but the dripping prevention structure DS may be formed only in the X direction, for example. .

  In the above embodiment, the liquid pool preventing structure is configured by the groove CT1 or the like provided in the light transmission member 23 of the light guide device 20. However, for example, the hole H1 or the corresponding groove CT1 or the like is provided as the light guide member 21. By providing the light guide member 21 on the side, the light guide member 21 may have an accumulation preventing structure. In the above embodiment, the liquid dripping prevention structure is configured by the stepped portion BU formed by the light guide member 21 and the light transmitting member 23 in cooperation with each other in the light guide device 20. However, it is also possible to have a stepped portion BU, that is, a liquid dripping prevention structure.

  In the said embodiment, although the hole H1, etc. for positioning are shown as a three-dimensional shape which is the object which provides the liquid pool prevention structure CS, the three-dimensional shape used as object is not restricted to this, The light guide apparatus 20 is shown. Various uneven structures may be provided. Further, the grooves CT1 and the like provided in the holes H1 and the like may have various shapes and structures as long as the uneven structure provided in the light guide device 20 can promote the flow of the coating liquid CL. Further, it can function as a liquid pool preventing structure CS, that is, a flow control structure FS. For example, the groove CT2 of the hole H2 is not only the concave hole shown in the hole H2, but also a groove extending from the middle of the through hole, such as a long hole shape or a key hole shape, in other words, a part of these concave holes is cut out. It can also be a notch formed. In addition, by providing relief grooves and stepped parts, liquid accumulation prevention structure CS and liquid dripping prevention structure DS are configured, but not limited to escape grooves and stepped parts, it is formed by cutting out the peripheral edge of a three-dimensional shape The liquid accumulation prevention structure CS and the liquid dripping prevention structure DS can also be configured by the tapered shape or the convex shape.

  In the above embodiment, the hard coat layer CC is formed by dip processing. However, the film forming method is not limited to dip processing as long as it can be formed with a predetermined film thickness. A coating method, a spray method, a roll coating method, a wet / dry coating method, and the like are also applicable.

  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. 18, a prism or block-shaped relay member 1125 separated from the light guide B <b> 2 can be used as the light incident part B <b> 1. 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 addition, about the surface extended also along a curved surface substantially here, it shall handle as a surface extended mutually.

  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, 21s, 23s ... Main-body part, 21 ... Light guide member, 21a, 21b ... Reflection surface (total reflection surface, light guide) Surface), 21c, 21d ... reflective surface (light guide surface), 21e ... upper surface, 21f ... lower surface, 21h ... end surface, 23 ... light transmitting member, 23a, 23b, 23c ... surface, 25 ... mirror layer, 28 ... half mirror Layer (semi-transmissive reflective film) 31. Illuminating device 32. Liquid crystal display device 32 b Display region 34 Drive controller 100 Virtual image display device 100 A, 100 B Display device 110 Optical panel 121 Frame, 131, 132 ... drive unit, AX1 ... first optical axis, AX2 ... second optical axis, B1 ... light incident unit, B2 ... light guide unit, B3 ... light emitting unit, B4 ... see-through unit, EY Eye, FF ... Flat surface, GL ... Image light, GL '... External light, GL11, GL12, GL21, GL22 ... Image light, IM1, IM2 ... Projection image, IS ... Light incident surface, L1, L2, L3 ... Lens, OS ... light emission surface, P1 ... display point, P2 ... display point, SL ... illumination light, CC ... hard coat layer, CL ... coat liquid, CT1, CT2, CT3 ... groove (escape groove), H1, H2, H3 ... Hole (positioning part), PA ... Base material, PB, PC ... Base material part, BU ... Stepped part, CS ... Liquid accumulation prevention structure, DS ... Liquid dripping prevention structure, FS ... Flow control structure

Claims (10)

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 part that guides the image light taken from the light incident part by total reflection on the first and second surfaces facing each other; A light emitting device having a light emitting part for taking out the image light having passed through the light guiding part to the outside,
With
The light guide device has a hard coat layer that is coated and hardened on a surface of the light guide portion that contributes to the light guide of the image light, and a flow control structure that controls the flow of the hard coat layer. And
The flow control structure includes a stepped portion in which a light guide surface of the light guide portion protrudes from a peripheral portion of the light guide surface, and the hard coat layer that has been coated and cured on the light guide surface side is excessive. It is a sagging prevention structure that prevents sagging of the hard coat layer so as not to become,
The step portion is had contact to the main beam direction in which the light flux of the image light is directed as a whole, is a step which is provided in a thickness direction of the light guide portion extending along a direction perpendicular to the main light direction,
Virtual image display device. 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 part that guides the image light taken from the light incident part by total reflection on the first and second surfaces facing each other; A light emitting device having a light emitting part for taking out the image light having passed through the light guiding part to the outside,
With
The light guide device has a hard coat layer that is coated and hardened on a surface of the light guide portion that contributes to the light guide of the image light, and a flow control structure that controls the flow of the hard coat layer. The flow control structure has a hard coat layer accumulation preventing structure that has a hard coat relief groove around a three-dimensional shape and prevents the hard coat layer from accumulating so that the hard coat layer does not become excessive. Is,
Virtual image display device. In the light guide device, the flow control structure includes a flow path of the hard coat layer so as to avoid a light guide surface of the light guide portion of the light guide device and an appearance portion exposed to the outside of the light guide device. Is set,
The virtual image display device according to claim 1. The light guide device has a positioning unit that performs relative positioning with other members including the projection optical system,
The virtual image display device according to claim 2, wherein the hard coat layer accumulation preventing structure is formed by providing the relief groove around the positioning portion. The hard coat layer accumulation prevention structure has the concave three-dimensional shape in the connecting portion on the distal end side of the support member that supports the light guide portion,
5. The virtual image display device according to claim 2, wherein the escape groove is a cutout portion formed by cutting out a part of the concave shape. The light guide device constitutes a light guide member including the light incident part, the light guide part, and the light emitting part, and a see-through part for observing external light by being joined to the light emitting part, and the light guide. A light transmissive member for supporting the member,
The virtual image display device according to claim 1, wherein the sagging prevention structure of the hard coat layer is formed by providing the step portion at a boundary between the light guide member and the light transmission member. 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;
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. 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 part that guides the image light taken from the light incident part by total reflection on the first and second surfaces facing each other, a light emission part that extracts the image light that has passed through the light guide part to the outside, and the image light A light guide device having a hard coat layer provided on the surface of the light guide portion that contributes to the light guide and a flow control structure that controls a flow of a coating liquid applied for film formation of the hard coat layer; A method of manufacturing a virtual image display device comprising:
A first step of preparing a flow control structure having a stepped portion in which a light guide surface of the light guide unit for controlling the flow of the coating liquid protrudes from a peripheral part of the light guide surface; and The hard coat layer is formed while preventing the coating liquid from dripping to the light guide surface side by applying and curing the coating liquid while controlling the flow of the coating liquid by the flow control structure prepared in A second step of forming a film,
The step portion is had contact to the main beam direction in which the light flux of the image light is directed as a whole, is a step which is provided in a thickness direction of the light guide portion extending along a direction perpendicular to the main light direction,
A method for manufacturing a virtual image display device. 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 part that guides the image light taken from the light incident part by total reflection on the first and second surfaces facing each other, a light emission part that extracts the image light that has passed through the light guide part to the outside, and the image light A light guide device having a hard coat layer provided on the surface of the light guide portion that contributes to the light guide and a flow control structure that controls a flow of a coating liquid applied for film formation of the hard coat layer; A method of manufacturing a virtual image display device comprising:
A first step of preparing a flow control structure for controlling the flow of the applied coating liquid in the light guide device;
The light guide by applying and curing the coating liquid around the three-dimensional shape of the flow control structure prepared in the first step while controlling the flow of the coating liquid in the relief groove of the coating liquid. A second step of forming the hard coat layer while preventing accumulation of the coating liquid on the surface side;
A method of manufacturing a virtual image display device having The dipping process step includes a pulling-up step of pulling up the base material to be the light guide device attached to the coating liquid tank so that the flow path of the coating liquid by the flow control structure is inclined. A method for manufacturing the virtual image display device according to claim 9.

Images