Virtual image display device and optical unit

Abstract

The invention provides a virtual image display device and an optical unit to improve the utilization efficiency of light. A virtual image display device or an optical unit is provided with: a first display device that emits circularly polarized image light; a planar first reflecting member that reflects the image light in an oblique direction; and a second reflective member that has positive refractive power and reflects the image light reflected by the first reflective member toward the first reflective member, the first reflective member including a first light functional layer that is either a cholesteric liquid crystal layer or a transmissive reflective layer. The second reflective member includes a second light functional layer that is the other of the cholesteric liquid crystal layer and the transmissive reflective layer. As a result, the orientation of the circularly polarized light can be switched by the transmissive reflective layer, and the image light can be efficiently reflected by the cholesteric liquid crystal layer, or the image light can be efficiently reflected and transmitted by the cholesteric liquid crystal layer.

Description

Technical Field

[0001] The present invention relates to a see-through virtual image display device and an optical unit capable of observing a virtual image. Background Art

[0002] As a folded optical system for a near-eye display, the following folded optical system is known: a circular polarizer, a partial reflector, and a reflective polarizer are provided in order from the display, and the reflective polarizer is, for example, a reflective CLC circular polarizer (see Patent Document 1). In this optical system, the light from the display becomes, for example, left-handed circularly polarized light after passing through the circular polarizer, and also maintains the polarization state after passing through the partial reflector, is reflected by the reflective polarizer, but maintains the state of left-handed circularly polarized light, reaches the partial reflector and is partially reflected. The left-handed circularly polarized light reflected by the partial reflector becomes right-handed circularly polarized light and passes directly through the reflective polarizer. Here, the light from the display is doubly reflected in the cavity formed by the partial reflector and the reflective polarizer, so that the physical total length can be prevented from increasing and the optical path length can be increased.

[0003] Patent Document 1: Japanese Patent Application No. 2021-532393

[0004] In the virtual image display device of the above-mentioned patent document 1, the display is arranged in front of the eyes, so the light shielding of the display becomes a problem for the light from the surrounding environment. In addition, in the case of a bird bath type virtual image display device combining a concave half mirror and a flat half mirror, the light shielding caused by the display does not become a problem, but the light utilization efficiency is low and the image light is easily leaked to the outside. Summary of the invention

[0005] A virtual image display device according to one aspect of the present invention comprises: a display which emits circularly polarized image light; a planar first reflecting component which reflects the image light in an oblique direction; and a second reflecting component which has a positive refractive power and reflects the image light reflected by the first reflecting component toward the first reflecting component, wherein the first reflecting component includes a first optical functional layer which is one of a cholesteric liquid crystal layer and a transmissive reflecting layer, and the second reflecting component includes a second optical functional layer which is the other of the cholesteric liquid crystal layer and the transmissive reflecting layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 This is an external view illustrating a usage state of the virtual image display device according to the first embodiment.

[0007] Figure 2 It is a side cross-sectional view illustrating the internal structure of a single display device.

[0008] Figure 3It is a stereoscopic diagram for explaining the appearance structure of the first display optical system.

[0009] Figure 4 Yes Description Figure 2 A conceptual diagram of the polarization state of image light, etc. in the device shown.

[0010] Figure 5 It is a description of Figure 2 A diagram showing a modified example of the first display of the device shown.

[0011] Figure 6 Yes Description Figure 2 FIG. 2 is a diagram of another variation of the device shown.

[0012] Figure 7 It is a side cross-sectional view for explaining the virtual image display device according to the second embodiment.

[0013] Figure 8 Yes Description Figure 7 A conceptual diagram of the polarization state of image light, etc. in the device shown.

[0014] Fig. 9 It is a side sectional view for explaining the virtual image display device according to the third embodiment.

[0015] Fig.10 Yes Description Fig. 9 A conceptual diagram of the polarization state of image light, etc. in the device shown.

[0016] Fig.11 Yes Description Fig. 9 A diagram showing a modified example of the device shown.

[0017] Fig.12 It is a side sectional view for explaining the virtual image display device according to the fourth embodiment.

[0018] Fig.13 Yes Description Fig.12 A conceptual diagram of the polarization state of image light, etc. in the device shown.

[0019] Description of symbols

[0020] 10a: 1st display; 10b: 2nd display; 11a: display element; 11b: polarizing plate; 11c: 1 / 4 wavelength plate; 11d: display surface; 20a: 1st display optical system; 20b: 2nd display optical system; 30: 1st coupling lens; 31: parallel plate; 32: lens part; 40: 1st flat plate-shaped member; 50: 2nd flat plate-shaped member; 41a: incident optical surface; 41b: inner side surface; 41c: outer side surface Side surface; 41d, 42d: inclined surface; 42b: inner side surface; 42c: outer side surface; 44: second coupling lens; 45: transmissive reflective layer; 48: prism light guide component; 50c: inner side surface; 53: first lens; 54: second lens; 53f: plane surface; 53g: convex surface; 54f: concave surface; 54g: plane surface; 55: compensation plate; 55f, 55g: plane surface; 56: cholesteric liquid crystal layer; 58: optical element; 61: spacer Partition; 71: housing; 90: user terminal; 100: optical unit; 100A: first virtual image display device; 100B: second virtual image display device; 100C: support device; 102a, 102b: display drive unit; 103a, 103b: combiner; 111r: cholesteric liquid crystal element; 156, 245, 356, 445: cholesteric liquid crystal layer; 256, 345, 456: transmissive reflective layer; 340 : Tilted reflector; 350: concave reflector; R1: 1st reflective component; R2: 2nd reflective component; F1: 1st optical functional layer; F2: 2nd optical functional layer; AX: optical axis; CR: focusing reflective part; CT: adhesive material; DIS: direct virtual image optical system; EP: exit pupil; IS: imaging optical system; ML: image light; OL: external light; PP: pupil position; PPa: opening; SP: gap; US: wearer. DETAILED DESCRIPTION

[0021] First Embodiment

[0022] Below, refer to Figure 1 , Figure 2 etc., a first embodiment of the virtual image display device etc. of the present invention is described.

[0023] Figure 1 2 is a diagram for explaining a wearing state of a head mounted virtual image display device (hereinafter also referred to as a head mounted display or HMD) 200, and the HMD 200 allows an observer or wearer US wearing the HMD to recognize an image as a virtual image. Figure 1 In the above, X, Y, and Z are orthogonal coordinate systems, the +X direction corresponds to the lateral direction in which the two eyes EY of the observer or wearer US wearing the HMD 200 are arranged, the +Y direction corresponds to the upward direction orthogonal to the lateral direction in which the two eyes EY of the wearer US are arranged, and the +Z direction corresponds to the front direction or the front direction of the wearer US. The ±Y directions are parallel to the vertical axis or the vertical direction.

[0024] The HMD 200 includes a first virtual image display device 100A of a direct virtual image type for the right eye, a second virtual image display device 100B of a direct virtual image type for the left eye, a pair of support devices 100C in the shape of temples that support these virtual image display devices 100A and 100B, and a user terminal 90 as an information terminal. The first virtual image display device 100A functions as an HMD alone, and is composed of a first display drive unit 102a arranged at the top and a first combiner 103a that covers the front of the eyes in the shape of a glasses lens. The second virtual image display device 100B also functions as an HMD alone, and is composed of a second display drive unit 102b arranged at the top and a second combiner 103b that covers the front of the eyes in the shape of a glasses lens. The support device 100C is a wearing component worn on the head of the wearer US, and supports the upper ends of the pair of combiners 103a and 103b via the display drive units 102a and 102b that are integrated in appearance. The first virtual image display device 100A and the second virtual image display device 100B are optically identical or left-right inverted, and detailed description of the second virtual image display device 100B is omitted.

[0025] Figure 2 1 is a side cross-sectional view for explaining the internal structure of the first virtual image display device 100A. The first virtual image display device 100A includes a first display 10a, a first display optical system 20a, and a first circuit component 80a. The first display 10a emits circularly polarized image light ML. The first display optical system 20a is an imaging optical system IS that directly forms a virtual image without forming an intermediate image, and is also called a direct virtual image optical system DIS. The imaging optical system IS includes a first coupling lens 30, a first flat plate member 40, and a second flat plate member 50. The first coupling lens 30 has a function as a protective glass for protecting the first display 10a. The first flat plate member 40 guides the image light ML emitted from the first display 10a to the first lens 53 of the second flat plate member 50. The second flat plate member 50 reflects the image light ML from the first flat plate member 40 toward the pupil position PP or the eye EY so as to return to the first flat plate member 40, and allows external light to enter the pupil position PP via the first flat plate member 40. The first coupling lens 30 , the first flat-plate member 40 , and the second flat-plate member 50 each function as a lens having positive refractive power.

[0026] Although detailed description is omitted, the second virtual image display device 100B includes a second display 10b, a second display optical system 20b, and a second circuit component 80b. The second display 10b is the same as the first display 10a, the second display optical system 20b is the same as the first display optical system 20a, and the second circuit component 80b is the same as the first circuit component 80a. The second display optical system 20b includes a first coupling lens 30, a first flat plate-shaped member 40, and a second flat plate-shaped member 50.

[0027] In the first virtual image display device 100A, the first display 10a emits circularly polarized image light ML to the first flat plate member 40 via the first coupling lens 30. The first display 10a is accommodated and supported in the housing 71 together with the first circuit member 80a. The first display 10a includes: a display element 11a that emits image light ML including polarized light in one direction or two directions; a polarizing plate 11b that is disposed opposite to the display element 11a; and a 1 / 4 wavelength plate 11c that is disposed on the opposite side of the display element 11a and opposite to the polarizing plate 11b.

[0028] The display element 11a is a self-luminous image light generating device. The display element 11a is, for example, an organic EL (Organic Electro-Luminescence) display, which forms a color static image or dynamic image on a two-dimensional display surface 11d. The display element 11a is driven by the first circuit component 80a to perform a display operation. The display element 11a is not limited to an organic EL display, and can be replaced by a display device using an inorganic EL, an organic LED, an LED array, a laser array, a quantum dot light-emitting element, etc. The display element 11a is not limited to a self-luminous image light generating device, and can also be a light modulating element such as a digital micromirror device. In this case, an image is formed by illuminating the light modulating element with a light source such as a backlight. In addition, in the first virtual image display device 100A, the optical device other than the first circuit component 80a is referred to as an optical unit 100. The optical unit 100 includes a direct virtual image type optical system, and can also be said to be a part equivalent to the direct virtual image optical system DIS constituting the first virtual image display device 100A.

[0029] The polarizing plate 11b limits the polarization direction of the image light ML emitted from the display element 11a to, for example, the D1 direction parallel to the YZ plane. The fast axis or slow axis of the 1 / 4 wavelength plate 11c is set, for example, to the middle direction between the D1 direction and the D2 direction perpendicular to the optical axis AX, and converts the linearly polarized light that has passed through the polarizing plate 11b into right-handed circularly polarized light c1. Here, the image light ML is circularly polarized light, which means that when focusing on the vibration of the electric field component or the magnetic field component of the image light ML, its vibration direction rotates at the frequency of the image light ML in a plane perpendicular to the direction of travel of the light, and the amplitude is constant regardless of its direction. Right-handed circularly polarized light is polarized light whose vibration direction of the electric field component rotates clockwise when observed by an observer standing in the direction from which the light comes, and left-handed circularly polarized light is polarized light that rotates counterclockwise. However, in this specification, if the image light ML mainly includes right-handed circularly polarized light, then, for example, even if it includes linearly polarized light in a specific direction, such image light ML is right-handed circularly polarized light c1.

[0030] In the case where the display element 11a only emits polarized light in the D1 direction as the image light ML, the polarizing plate 11b can be omitted. Specifically, in the case where the display element 11a is a light modulating element such as an LCD, a polarizing element is attached to the light emitting portion of the display element 11a, so the polarizing plate 11b is not required. As the display element 11a, in the case where LCOS (Liquid crystal silicon, LCoS is a registered trademark) is used instead of LCD, the polarizing plate 11b is not required. In the case where the display element 11a is a laser array that only emits polarized light in the D1 direction as the image light ML, the polarizing plate 11b is also not required.

[0031] The first display optical system 20a includes a first coupling lens 30, a first flat plate member 40, and a second flat plate member 50. The first flat plate member 40 includes a transmissive reflective layer 45 as a first optical functional layer F1 of the first reflective member R1, and the second flat plate member 50 includes a cholesteric liquid crystal layer 56 as a second optical functional layer F2 of the second reflective member R2. In the first display optical system 20a, the first coupling lens 30 has a positive refractive power, and the image light ML from the first display 10a enters the first coupling lens 30. The first coupling lens 30 has a planar light incident surface 30f joined to the first display 10a and a convex light exit surface 30g. The light exit surface 30g is, for example, a spherical surface, but can be an aspherical surface having an axially symmetrical shape. The first coupling lens 30 can be considered as a parallel plate 31 and a lens portion 32. By ensuring that the thickness of the parallel plate 31 is greater than a predetermined thickness, foreign matter attached to the surface of the first coupling lens 30 is less likely to become conspicuous. The lens portion 32 is a plano-convex lens. The first coupling lens 30 is made of, for example, fused silica and has a low refractive index.

[0032] The first flat plate-shaped member 40 has a first prism 41 in the form of a parallel flat plate, a second prism 42 in the form of a parallel flat plate, and a transmissive reflective layer 45 arranged in a manner sandwiched therebetween. The first prism 41 and the second prism 42 are joined via inclined surfaces 41d and 42d. The member formed by joining the first prism 41 and the second prism 42 is referred to as a prism light guide member 48. The prism light guide member 48 has the appearance of parallel flat plates. A planar transmissive reflective layer 45 is formed on the inclined surface 41d formed on the lower side of the first prism 41. The member formed by combining the prism light guide member 48 and the second flat plate-shaped member 50 described later is equivalent to Figure 1 The first combiner 103a.

[0033] The first prism 41 has a quadrangular prism-shaped outer shape and a trapezoidal cross-section. The first prism 41 guides the image light ML and has an incident optical surface 41a, an inner side surface 41b, an outer side surface 41c and an inclined surface 41d. Here, the incident optical surface 41a is tilted downward in the front direction as a whole. The optical axis AX passing through the incident optical surface 41a extends in a direction between the -Z direction as the rear and the -Y direction as the bottom. As a result, it is easy to configure the first display 10a at a position closer to the outside side than the inner side surface 41b, and the angle at which the image light ML propagates in the first prism 41 can be adjusted. The incident optical surface 41a is a convex surface, for example, a spherical surface, but can be set as an axisymmetric aspherical surface. It can be considered that the first prism 41 has a second coupling lens 44 including the incident optical surface 41a. The second coupling lens 44 is a convex-planar lens with positive refractive power. The inner side surface 41b and the outer side surface 41c are parallel to each other and extend perpendicularly to the optical axis AX between the pupil positions PP. The inner side surface 41b and the outer side surface 41c reflect the image light ML internally (i.e., reflect it on the inner side of the object surface), but it is particularly preferred to perform total reflection. The inner side surface 41b can improve the scratch resistance or abrasion resistance by applying a hard coating. The inclined surface 41d is a plane. Regarding the inclined surface 41d, an acute angle is formed relative to the outer side surface 41c, specifically, an angle of 25° to 32°. In addition, the interval between the optical axis AX passing through the pupil position PP and the upper end of the first coupling lens 30 is about 20 mm. The first prism 41 is formed of a resin material and has a refractive index higher than the refractive index of the first coupling lens 30.

[0034] The second coupling lens 44 can be omitted. That is, the incident optical surface 41a may be a flat surface.

[0035] The number of reflections of the image light ML in the first prism 41 is once on the inner side surface 41b, once on the outer side surface 41c, and further reflected once by the later-described transmissive reflective layer 45. By setting the number of internal reflections of the image light ML in the first prism 41 to 2 times, the viewing angle of the image light ML, the pupil position PP or its opening PPa can be increased, and the mixing of lights having different reflection times in the first prism 41 can be avoided. Since no intermediate image is formed in the first display optical system 20a or the imaging optical system IS, the image light ML reflected by the inner side surface 41b and the outer side surface 41c has a suppressed degree of divergence compared to the initial divergence state emitted from the first display 10a, i.e., the display element 11a, but is incident on the inner side surface 41b and the outer side surface 41c in a divergent state, and the divergent state is maintained.

[0036] The second prism 42 has a quadrangular prism-shaped outer shape similar to the first prism 41 and has a trapezoidal cross section. The second prism 42 allows the image light ML to pass through, and has an inner side surface 42b, an outer side surface 42c and an inclined surface 42d. Here, the inner side surface 42b and the outer side surface 42c are parallel to each other and extend perpendicularly to the optical axis AX between the pupil positions PP. By applying a hard coating to the inner side surface 42b, the scratch resistance can be improved. The second prism 42 is formed of a resin material and has a refractive index equal to that of the first prism 41.

[0037] The transmissive reflective layer 45 is a flat first reflective member R1 that reflects the image light ML in an oblique direction. The transmissive reflective layer 45 is integrally formed on the inclined surface 41d of the first prism 41, and is sandwiched between the inclined surface 41d of the first prism 41 and the inclined surface 42d of the second prism 42. That is, it is provided at the junction of the first prism 41 and the second prism 42. The space between the transmissive reflective layer 45 and the inclined surface 42d is filled with an adhesive material CT for bonding. The transmissive reflective layer 45 is formed by a single-layer film or a multilayer film of a metal such as Al, Ag, etc., with a film thickness adjusted. The transmissive reflective layer 45 is formed, for example, by lamination using vapor deposition. The transmissive reflective layer 45 may also be a dielectric multilayer film composed of a plurality of dielectric layers with a film thickness adjusted. From the viewpoint of ensuring the brightness of the image light ML and facilitating observation of external images by perspective, the reflectivity of the transmissive reflective layer 45 to the image light ML and the external light OL is, for example, 50% or more within the assumed incident angle range of the image light ML.

[0038] When the reflection angle of the image light ML on the optical axis AX in the first prism 41 is β0, the inclination angle θ of the transmissive reflective layer 45 is θ=β0 / 2. As a premise that the transmissive reflective layer 45 does not hinder the path of the image light ML, when the maximum reflection angle of the image light ML is βmax, the inclination angle θ of the transmissive reflective layer 45 is preferably less than 90°-βmax. The reflection angle β0 of the image light ML is equivalent to the angle formed by the normal line of the inner side surface 41b and the optical axis AX passing through the incident optical surface 41a.

[0039] The second flat member 50 includes a plano-convex first lens 53 , a concave-planar second lens 54 , a compensation plate 55 provided around the second lens 54 , and a cholesteric liquid crystal layer 56 disposed so as to be sandwiched between the first lens 53 and the second lens 54 .

[0040] The second flat plate-shaped member 50 is configured to be separated from the first flat plate-shaped member 40 by, for example, about 20 μm to 50 μm. By making the interval between the outer side surfaces 41c, 42c and the inner side surface 50c 20 μm or more, more preferably 30 μm or more, it is possible to avoid these surfaces from being too close. On the contrary, by making the interval between the outer side surfaces 41c, 42c and the inner side surface 50c 50 μm or less, it is possible to avoid the thickness of the first combiner 103a formed by combining the first flat plate-shaped member 40 and the second flat plate-shaped member 50 to increase. A spacer 61 is provided between the outer side surfaces 41c, 42c of the first flat plate-shaped member 40 and the inner side surface 50c of the second flat plate-shaped member 50, and the spacer 61 is used to fix the first flat plate-shaped member 40 and the second flat plate-shaped member 50 in a state of being positioned mutually by adjusting the interval between them. The spacer 61 is not provided over the entire circumference of the second flat plate-shaped member 50. That is, the gap SP between the first flat-plate-shaped member 40 and the second flat-plate-shaped member 50 is not sealed but communicates with the outside.

[0041] The first lens 53 is thin but has positive refractive power, and has a flat surface 53f facing the outer side surfaces 41c and 42c of the first flat plate-shaped member 40 and a convex surface 53g facing the second lens 54. The convex surface 53g is, for example, a spherical surface, but can be set to an aspherical surface with axial symmetry. The second lens 54 is thin but has negative refractive power, and has a concave surface 54f and a flat surface 54g facing the first lens 53. The compensation plate 55 is a parallel plate and has a pair of flat surfaces 55f and 55g. Here, the concave surface 54f of the second lens 54 has the same shape as the convex surface 53g of the first lens 53. The flat surface 53f of the first lens 53 and the flat surface 55f of the compensation plate 55 are located on the same plane. The flat surface 54g of the second lens 54 and the flat surface 55g of the compensation plate 55 are continuous on the same plane. The cholesteric liquid crystal layer 56 is a thin film formed on the convex surface 53g of the first lens 53, and has the same shape as the convex surface 53g. A combination of the first lens 53 and the cholesteric liquid crystal layer 56 is referred to as a light-collecting reflection portion CR.

[0042] The first lens 53, the second lens 54 and the compensation plate 55 are formed of a resin material and have the same refractive index. The refractive index of the first lens 53 and the like is lower than that of the first prism 41. The second lens 54 and the compensation plate 55 are an optical element 58 formed integrally of the same resin material. The combination of the first lens 53, the second lens 54 and the compensation plate 55 functions as a parallel plate as a whole. That is, the external light OL incident on the position of the second lens 54 and the compensation plate 55 passes through them without being affected by the lens effect of the second lens 54 and the like and the step existing at the outer edge of the second lens 54. The planes 54g and 55g of the second lens 54 and the compensation plate 55 can be provided with an anti-reflection film or a hard coating. The external light OL passing through the compensation plate 55 is incident on the second flat member 50 from the upper, lower, left, right, and right sides of the second lens 54, that is, from the peripheral areas outside the incident area of ​​the image light ML. Thus, a wide perspective field of view with respect to the outside world can be ensured. The field of view of the external light OL is set to, for example, about 40° upward and about 40° downward.

[0043] From the viewpoint of ensuring the viewing angle, the diameter of the first lens 53 is set to 20 mm to 25 mm. In addition, the thickness of the first flat member 40 or the prism light guide member 48 in the Z direction is 6 mm to 8 mm, and the distance from the inner side surfaces 41 b and 42 b of the first flat member 40 to the pupil position PP is about 12 mm to 13 mm. Therefore, the angle range, i.e., the viewing angle (diagonal angle), of the image light ML incident on the pupil position PP can be set to about 40°.

[0044] The cholesteric liquid crystal layer 56 is a second reflecting member R2 or a part thereof that reflects the image light ML reflected by the transmissive reflecting layer 45 as the first reflecting member R1 toward the transmissive reflecting layer 45. The cholesteric liquid crystal layer 56 selectively reflects the image light ML that is reflected by the transmissive reflecting layer 45 and becomes the left-handed circularly polarized light c2 while maintaining it in the state of the left-handed circularly polarized light c2. That is, the cholesteric liquid crystal layer 56 hardly transmits the image light ML and prevents the image light ML from being emitted to the outside. On the other hand, the outside light OL includes the right-handed circularly polarized light and the left-handed circularly polarized light, so the cholesteric liquid crystal layer 56 transmits the right-handed circularly polarized light. That is, the cholesteric liquid crystal layer 56 partially transmits the outside light OL. The cholesteric liquid crystal layer 56 reflects the image light ML that is reflected by the transmissive reflecting layer 45 of the first flat plate-shaped member 40 and passes through the first lens 53 toward the pupil position PP. The image light ML reflected by the cholesteric liquid crystal layer 56 partially passes through the transmissive reflective layer 45 of the prism light guide member 48 and enters the pupil position PP. The cholesteric liquid crystal layer 56 is a concave reflector that covers the pupil position PP where the eye EY or pupil is arranged and has a concave shape toward the pupil position PP and a convex shape toward the outside. The pupil position PP or its opening PPa is called an eye point or an eye box, and corresponds to the exit pupil EP of the first display optical system 20a.

[0045] The cholesteric liquid crystal layer 56 transmits a part of the external light OL, so that the external world can be observed through the lens, and a virtual image can be overlapped with the external image. At this time, the external light OL passes through the first flat member 40 and the second flat member 50, but the flat members 40 and 50 do not produce a lens effect on the external light OL.

[0046] The cholesteric liquid crystal layer 56 has a layered structure of molecules oriented in a fixed direction, and there is a twist in the molecular orientation axis between adjacent layers, and as a whole, the orientation direction is a spiral structure around the vertical axis of the layer. The cholesteric liquid crystal layer 56 is composed of a specified liquid crystal material, and has the property of transmitting right-handed circularly polarized light c1 and reflecting left-handed circularly polarized light c2. The cholesteric liquid crystal layer 56 is formed by sandwiching a liquid crystal substrate containing liquid crystal material and additives between the first lens 53 and the second lens 54, and by irradiating the liquid crystal substrate sandwiched between them with UV light or the like, or by removing the solvent from the liquid crystal substrate sandwiched between them or evaporating the solvent, or by heating the liquid crystal substrate sandwiched between them, so as to become a liquid crystal material layer in a stable state with suppressed fluidity. For example, the cholesteric liquid crystal layer 56 can also be cured on the surface of one of the first lens 53 and the second lens 54, and the other of the first lens 53 and the second lens 54 is attached so that they sandwich the cholesteric liquid crystal layer 56. In addition, regarding the production of the cholesteric liquid crystal layer 56 , the methods described in Japanese Patent Application Publication No. 2008-501147 and Japanese Patent Application Publication No. 2021-532393 can be applied.

[0047] In the first virtual image display device 100A, the first coupling lens 30, the second coupling lens 44, the first lens 53, and the cholesteric liquid crystal layer 56 each have a positive refractive power and have a tendency to converge divergent light. The first coupling lens 30, the second coupling lens 44, the first lens 53, and the cholesteric liquid crystal layer 56, including the main body of the first prism 41, the second prism 42, etc., function as an imaging optical system IS or a direct virtual image optical system DIS such as a single-type microscope type microscope that forms an erect image. As a result, a real image formed on the display surface 11d of the display element 11a can be projected to, for example, an infinity virtual image, or a real image formed on the display surface 11d can be projected to several meters in front of the virtual image. At this time, by adjusting the refractive power or refractive power of the first coupling lens 30, the second coupling lens 44, the first lens 53, and the cholesteric liquid crystal layer 56, the focal length of the imaging optical system IS can be shortened to achieve a desired magnification.

[0048] Reference Figure 3 The dimensions of the first flat plate member 40 or the second flat plate member 50 in the vertical and horizontal directions, i.e., in the XY direction, are, for example, about 34 mm×40 mm, and the thickness of the first flat plate member 40 and the second flat plate member 50 in the front-to-back direction after the combination is suppressed to about 7.5 mm. The width and depth dimensions of the display element 11a and the first coupling lens 30 are, for example, about 7 mm×14 mm.

[0049] In the first flat plate-shaped member 40, an upper plane 40u is provided on the left and right of the incident optical surface 41a. Light is not incident on the upper plane 40u. From the viewpoint of preventing stray light, a light shielding body (not shown) can be arranged on the upper plane 40u to cover it, or a light shielding body can be applied. A light shielding body or the like that covers the horizontal plane 40v and the lower plane 40w can also be provided. A light shielding body or the like that covers the second flat plate-shaped member 50 can also be provided around it.

[0050] The curvature radius of the convex light emitting surface 30g of the first coupling lens 30 is, for example, 20 mm. The curvature radius of the incident optical surface 41a of the first prism 41 is, for example, 14 mm, and the curvature radius of the cholesteric liquid crystal layer 56 is, for example, 47 mm.

[0051] For a description of the optical path, refer to Figure 2 The image light ML emitted from the first display 10a is right-handed circularly polarized light c1, and enters the first prism 41 through the first coupling lens 30. At this time, the image light ML is suppressed in its divergence by the positive refractive power of the first coupling lens 30 and the second coupling lens 44. In the optical path through the first prism 41, the image light ML does not form an intermediate image, but is reflected in sequence by the inner side surface 41b of the first prism 41 and the outer side surface 41c of the first prism 41, and a part of the image light ML is reflected by the transmissive reflective layer 45. The image light ML reflected by the transmissive reflective layer 45 becomes left-handed circularly polarized light c2. The image light ML reflected by the transmissive reflective layer 45 passes through the outer side surface 41c of the first prism 41, and enters the cholesteric liquid crystal layer 56 through the first lens 53. The left-handed circularly polarized light c2 incident on the cholesteric liquid crystal layer 56 is mostly reflected by the cholesteric liquid crystal layer 56, collimated by the first lens 53, incident on the first prism 41 from the outer side surface 41c, partially transmitted through the transmissive reflective layer 45, and emitted to the outside of the second prism 42 through the inner side surface 42b. The image light ML emitted to the outside of the second prism 42 is incident on the pupil position PP where the eye EY or pupil of the wearer US is arranged. At the pupil position PP, not only the image light ML reflected by the cholesteric liquid crystal layer 56 but also the external light OL that has transmitted through the cholesteric liquid crystal layer 56 and the external light OL that has passed through the compensation plate 55 are incident. That is, the wearer US wearing the first virtual image display device 100A can observe the virtual image based on the image light ML in an overlapping manner with the external image.

[0052] Reference Figure 4, the image light ML from the first display 10a is right-handed circularly polarized light, and is reflected by the inner side surface 41b and the outer side surface 41c of the first prism 41 and enters the transmissive reflective layer 45 in the state of right-handed circularly polarized light. The image light ML reflected by the transmissive reflective layer 45 is converted from right-handed circularly polarized light to left-handed circularly polarized light, and enters the cholesteric liquid crystal layer 56 via the outer side surface 41c and the like. The image light ML reflected by the cholesteric liquid crystal layer 56 is maintained as left-handed circularly polarized light, and passes through the outer side surface 41c, the transmissive reflective layer 45, and the inner side surface 42b in the state of left-handed circularly polarized light. In the above, the cholesteric liquid crystal layer 56 reflects almost all of the image light ML as left-handed circularly polarized light, so that the image light ML is almost entirely blocked by the second flat plate-shaped member 50 and does not leak to the outside. That is, it is possible to prevent the image light ML from being observed from the outside, so that privacy can be ensured.

[0053] Regarding the external light OL, the right-handed circularly polarized light selectively passes through the cholesteric liquid crystal layer 56 , and passes through the outer side surface 41 c , the transmissive reflective layer 45 , and the inner side surface 42 b in the state of right-handed circularly polarized light.

[0054] In the above, the reflectivity of the transmissive reflective layer 45 is set to, for example, 50%. In this case, the image light ML emitted from the display element 11a is attenuated to, for example, 50% by the polarizing plate 11b, and further attenuated to 25% by the transmissive reflective layer 45, but even if it is reflected by the cholesteric liquid crystal layer 56, it is maintained at 25% based on the original display element 11a. The intensity of the image light ML incident on the pupil position PP through the transmissive reflective layer 45 is 12.5% ​​based on the original display element 11a. The external light OL is maintained at the original 50%.

[0055] The first display 10a is not limited to emitting image light ML of a specific wavelength, but may also emit colored image light ML. In this case, it is preferred that the cholesteric liquid crystal layer 56 also corresponds to the visible wavelength band. In order to make the cholesteric liquid crystal layer 56 correspond to multiple wavelengths, for example, a multilayer structure including element layers corresponding to RGB colors can be provided.

[0056] Figure 5 Yes Description Figure 2 1 is a diagram showing a modified example of the first display 10a. In this case, the first display 10a includes a display element 11a that emits image light ML including polarized light in one direction or two directions, and a cholesteric liquid crystal element 111r disposed opposite to the display element 11a. The cholesteric liquid crystal element 111r selectively allows only the right-handed circularly polarized light c1 component of the image light ML emitted from the display element 11a to pass. That is, only the right-handed circularly polarized light c1 is emitted from the first display 10a as the image light ML.

[0057] Figure 6 Yes Description Figure 210a. In this case, the image light ML emitted from the first display 10a is left-handed circularly polarized light, and the cholesteric liquid crystal layer 156 transmits the left-handed circularly polarized light and reflects the right-handed circularly polarized light. In this case, the image light ML is also almost completely blocked by the second flat member 50 or the cholesteric liquid crystal layer 156, and the image light ML does not leak to the outside. On the other hand, since the second flat member 50 transmits the external light OL, the wearer US can observe the virtual image based on the image light ML in an overlapping manner with the external image.

[0058] The virtual image display device 100A, 100B or the optical unit 100 of the first embodiment described above comprises: a first display device 10, which emits circularly polarized image light ML; a planar first reflecting component R1, which reflects the image light ML in an oblique direction; and a second reflecting component R2, which has a positive refractive power and reflects the image light ML reflected by the first reflecting component R1 toward the first reflecting component R1, the first reflecting component R1 includes a first optical functional layer F1 which is one of the cholesteric liquid crystal layer 56 and the transmissive reflecting layer 45, and the second reflecting component R2 includes a second optical functional layer F2 which is the other of the cholesteric liquid crystal layer 56 and the transmissive reflecting layer 45.

[0059] In the above-mentioned virtual image display device, the first reflecting member R1 reflects the image light ML in an oblique direction, so that the optical configuration in which the display 10a is arranged in front of the eye can be avoided. In addition, in the virtual image display devices 100A and 100B, one of the first reflecting member R1 and the second reflecting member R2 includes the cholesteric liquid crystal layer 56, and the other of the first reflecting member R1 and the second reflecting member R2 includes the transmissive reflective layer 45, so that the direction of the circularly polarized light can be switched by the transmissive reflective layer 45, and the image light ML can be efficiently reflected by the cholesteric liquid crystal layer 56, so that the light utilization efficiency can be simply improved.

[0060] In the virtual image display devices 100A and 100B of the first embodiment, the first reflective member R1 includes a transmissive reflective layer 45 as the first optical functional layer F1, and the second reflective member R2 includes a cholesteric liquid crystal layer 56 as the second optical functional layer F2. In this case, the circularly polarized light reflected by the transmissive reflective layer 45 of the first reflective member R1 is almost entirely reflected by the cholesteric liquid crystal layer 56 of the second reflective member R2, thereby preventing the image light ML from leaking to the outside.

[0061] Second Embodiment

[0062] Hereinafter, a virtual image display device according to a second embodiment will be described. The virtual image display device according to the second embodiment is obtained by partially modifying the virtual image display device according to the first embodiment, and description of the same parts as those of the virtual image display device according to the first embodiment will be omitted.

[0063] exist Figure 7 In the virtual image display device 100A or the optical unit 100 shown in the figure, the cholesteric liquid crystal layer 245 is used as the first optical function layer F1 of the first reflective member R1, and the transmissive reflective layer 256 is used as the second optical function layer F2 of the second reflective member R2. Figure 2 The transmissive reflective layer 256 as the second optical functional layer F2 is the same as the cholesteric liquid crystal layer 56 shown. Figure 2 The transmissive reflective layer 45 shown is the same. That is, compared with the first embodiment, the arrangement of the cholesteric liquid crystal layer 245 and the transmissive reflective layer 256 is reversed.

[0064] Reference Figure 8 The image light ML from the first display 10a is left-handed circularly polarized light, which is reflected by the inner side surface 41b and the outer side surface 41c of the first prism 41 and enters the first optical functional layer F1, namely the cholesteric liquid crystal layer 245, in the state of left-handed circularly polarized light and is almost completely reflected. The image light ML reflected by the cholesteric liquid crystal layer 245 is maintained in the state of left-handed circularly polarized light, and enters the transmissive reflective layer 256 as the second optical functional layer F2 through the outer side surface 41c and the like. The image light ML reflected by the transmissive reflective layer 256 is converted from left-handed circularly polarized light to right-handed circularly polarized light, and passes through the outer side surface 41c, the cholesteric liquid crystal layer 245 and the inner side surface 42b in the state of right-handed circularly polarized light. As described above, the cholesteric liquid crystal layer 245 reflects almost all of the image light ML as left-handed circularly polarized light and transmits almost all of the image light ML as right-handed circularly polarized light, so the image light ML is not attenuated due to reflection and transmission at the cholesteric liquid crystal layer 245.

[0065] The external light OL partially passes through the transmissive reflective layer 256. The external light OL partially passing through the transmissive reflective layer 256 enters the cholesteric liquid crystal layer 245 via the outer side surface 41c and the like, and only the right-handed circularly polarized light component of the external light OL selectively passes through the cholesteric liquid crystal layer 245 and passes through the inner side surface 42b in the state of right-handed circularly polarized light.

[0066] In the above, the transmissive reflective layer 256 is set to have a reflectivity of, for example, 50%. In this case, the image light ML emitted from the display element 11a is attenuated to, for example, 50% by the polarizing plate 11b, but even if it is reflected by the cholesteric liquid crystal layer 245, it is maintained at 50% based on the original display element 11a. The image light ML reflected by the cholesteric liquid crystal layer 245 is attenuated to 25% by reflection in the transmissive reflective layer 256, so the intensity of the image light ML incident on the pupil position PP through the cholesteric liquid crystal layer 245 becomes 25% based on the original display element 11a. The external light OL is maintained at the original 50%.

[0067] In the first display 10a, the polarizing plate 11b and the quarter-wave plate 11c can be replaced by Figure 5 The cholesteric liquid crystal element 111r is shown.

[0068] The cholesteric liquid crystal layer 245 may reflect right-handed circularly polarized light and transmit left-handed circularly polarized light. In this case, the right-handed circularly polarized light is emitted from the first display 10 a as the image light ML.

[0069] In the virtual image display device 100A, 100B of the second embodiment, the first reflective member R1 includes a cholesteric liquid crystal layer 245 as the first optical functional layer F1, and the second reflective member R2 includes a transmissive reflective layer 256 as the second optical functional layer F2. In this case, there is almost no attenuation of the image light ML when it is reflected and transmitted at the cholesteric liquid crystal layer 245. That is, the image light ML can be efficiently reflected and transmitted by the cholesteric liquid crystal layer 56, and the light utilization efficiency can be improved.

[0070] Third Embodiment

[0071] Hereinafter, a virtual image display device according to a third embodiment will be described. The virtual image display device according to the third embodiment is a partially modified virtual image display device according to the first embodiment, and description of the same parts as those of the virtual image display device according to the first embodiment will be omitted.

[0072] Reference Fig. 9 The virtual image display device 100A or the optical unit 100 includes a first display 10a and a first display optical system 320a.

[0073] The first display optical system 320a is an imaging optical system IS that directly forms a virtual image without forming an intermediate image. The imaging optical system IS includes a tilted reflection mirror 340 as a first reflection member R1 and a concave reflection mirror 350 as a second reflection member R2.

[0074] The tilted reflector 340, i.e., the first reflector R1, includes a first support substrate 40a in the shape of a parallel plate and supporting the first optical functional layer F1, and is arranged in a tilted state opposite to the first display 10a. The concave reflector 350, i.e., the second reflector R2, includes a second support substrate 50a, which is curved and has a uniform thickness and supports the second optical functional layer F2. The first support substrate 40a of the tilted reflector 340 supports a transmissive reflective layer 345 as the first optical functional layer F1 on the surface opposite to the second reflector R2. The second support substrate 50a of the concave reflector 350 supports a cholesteric liquid crystal layer 356 as the second optical functional layer F2 on the inner surface opposite to the first reflector R1.

[0075] Reference Fig.10 , the image light ML from the first display 10a is right-handed circularly polarized light, and enters the transmissive reflective layer 345 in the state of right-handed circularly polarized light. The image light ML reflected by the transmissive reflective layer 345 is converted from right-handed circularly polarized light to left-handed circularly polarized light, and enters the cholesteric liquid crystal layer 356. The image light ML reflected by the cholesteric liquid crystal layer 356 maintains the state of left-handed circularly polarized light, and passes through the transmissive reflective layer 345 in the state of left-handed circularly polarized light. In the above, the cholesteric liquid crystal layer 356 reflects almost all of the image light ML as left-handed circularly polarized light, so that the image light ML is almost completely blocked by the concave reflector 350, that is, the second reflective component R2, and does not leak to the outside. That is, it is possible to prevent the image light ML from being observed from the outside, so that privacy can be ensured.

[0076] Regarding the external light OL, the right-handed circularly polarized light component selectively passes through the cholesteric liquid crystal layer 356 , and passes through the transmissive reflective layer 345 in the state of right-handed circularly polarized light.

[0077] Fig.11 Yes Description Fig. 9 1 is a diagram of a modified example of a virtual image display device 100A or an optical unit 100. In this case, the second supporting substrate 50a includes a pair of bonded substrate elements 50aa and 50ab, and a cholesteric liquid crystal layer 356 as the second optical functional layer F2 is supported between the pair of substrate elements 50aa and 50ab.

[0078] Fourth Embodiment

[0079] Hereinafter, a virtual image display device according to a fourth embodiment will be described. The virtual image display device according to the fourth embodiment is a device obtained by partially modifying the virtual image display device according to the third embodiment, and description of the same parts as those of the virtual image display device according to the third embodiment will be omitted.

[0080] Reference Fig.12 The virtual image display device 100A or the optical unit 100 includes a first display 10a and a first display optical system 420a.

[0081] The first display optical system 420a is an imaging optical system IS that directly forms a virtual image without forming an intermediate image. The imaging optical system IS includes a tilted reflection mirror 340 as a first reflection member R1 and a concave reflection mirror 350 as a second reflection member R2.

[0082] The first supporting substrate 40a of the tilted reflector 340 supports a cholesteric liquid crystal layer 445 as the first optical functional layer F1 on the surface opposite to the second reflecting member R2. The second supporting substrate 50a of the concave reflector 350 supports a transmissive reflective layer 456 as the second optical functional layer F2 on the inner surface opposite to the first reflecting member R1. That is, compared with the third embodiment, the configurations of the cholesteric liquid crystal layer 445 and the transmissive reflective layer 456 are reversed.

[0083] Reference Fig.13 , the image light ML from the first display 10a is left-handed circularly polarized light, and enters the first optical functional layer F1, i.e., the cholesteric liquid crystal layer 445, in the state of left-handed circularly polarized light, and is almost entirely reflected. The image light ML reflected by the cholesteric liquid crystal layer 445 is maintained in the state of left-handed circularly polarized light, and enters the transmissive reflective layer 456, which is the second optical functional layer F2. The image light ML reflected by the transmissive reflective layer 456 is converted from left-handed circularly polarized light to right-handed circularly polarized light, and passes through the cholesteric liquid crystal layer 445 in the state of right-handed circularly polarized light. In the above, the cholesteric liquid crystal layer 445 reflects almost all of the image light ML as left-handed circularly polarized light, and allows almost all of the image light ML as right-handed circularly polarized light to pass through, so the image light ML is not attenuated by reflection and transmission at the cholesteric liquid crystal layer 445.

[0084] The external light OL partially passes through the transmissive reflective layer 456. The external light OL partially passing through the transmissive reflective layer 456 enters the cholesteric liquid crystal layer 445, and only the right-handed circularly polarized light component of the external light OL selectively passes through the cholesteric liquid crystal layer 445.

[0085] Modifications and others

[0086] The present invention has been described based on the above embodiments, but the present invention is not limited to the above embodiments, and can be implemented in various forms within the scope not departing from the gist of the present invention. For example, the following modifications are also possible.

[0087] In the above description, the HMD 200 includes the first virtual image display device 100A and the second virtual image display device 100B. However, the HMD 200 may support a single first virtual image display device 100A or a single second virtual image display device 100B in front of the eyes via the support device 100C.

[0088] The imaging optical system IS of the virtual image display devices 100A and 100B may form an intermediate image on the optical path from the first display 10 a to the second reflecting member R2 .

[0089] The compensating plate 55 can be omitted in the second flat plate-shaped member 50 . In this case, the first lens 53 is covered by the second lens 54 .

[0090] The first coupling lens 30 is not limited to being integrated with the first display 10 a , and may be disposed separately from the first display 10 a .

[0091] The polarizing plate 11 b and the quarter-wave plate 11 c may be disposed separately from the display element 11 a , for example, at a subsequent stage of the first coupling lens 30 .

[0092] The first display 10a may be a scanning type display including a laser light source and a scanning mirror.

[0093] A virtual image display device in a specific embodiment comprises: a display that emits circularly polarized image light; a planar first reflecting component that reflects the image light in an oblique direction; and a second reflecting component that has a positive refractive power and reflects the image light reflected by the first reflecting component toward the first reflecting component, wherein the first reflecting component includes a first optical functional layer that is one of a cholesteric liquid crystal layer and a transmissive reflecting layer, and the second reflecting component includes a second optical functional layer that is the other of a cholesteric liquid crystal layer and a transmissive reflecting layer.

[0094] In the above virtual image display device, since the first reflecting member reflects the image light in an oblique direction, an optical configuration in which the display is arranged in front of the eyes can be avoided. In addition, in the virtual image display device, one of the first reflecting member and the second reflecting member includes a cholesteric liquid crystal layer, and the other of the first reflecting member and the second reflecting member includes a transmissive reflecting layer, so that the direction of the circularly polarized light can be switched by the transmissive reflecting layer, and the image light can be efficiently reflected by the cholesteric liquid crystal layer, or the image light can be efficiently reflected and transmitted by the cholesteric liquid crystal layer, so that the light utilization efficiency can be simply improved.

[0095] In a specific aspect, the first reflecting member includes a transmissive reflecting layer as the first optical functional layer, and the second reflecting member includes a cholesteric liquid crystal layer as the second optical functional layer. In this case, the circularly polarized light reflected by the transmissive reflecting layer of the first reflecting member is almost entirely reflected by the cholesteric liquid crystal layer of the second reflecting member, thereby preventing the image light from leaking to the outside.

[0096] In a specific aspect, the present invention comprises: a first prism, on which image light from a display is incident; and a second prism, which is joined to the first prism to form a parallel flat plate-shaped prism light guide member, and a first reflecting member is provided at a joining portion between the first prism and the second prism. In this case, image light incident from the display to the first prism and guided in the first prism is reflected in an oblique direction by the first reflecting member, and image light from the first reflecting member is reflected by the second reflecting member, passes through the prism light guide member, and is incident on the pupil position.

[0097] In a specific aspect, the second reflecting component has a second lens and a plano-convex first lens, the plano-convex first lens has a plane arranged opposite to the outer side of the first prism and a convex surface arranged on the opposite side of the first prism across the plane, the second lens has a concave surface and a plane, the concave surface has a shape obtained by inverting the convex surface of the first lens and is bonded to the convex surface across the second optical functional layer, and the plane is arranged parallel to the outer side surface of the first prism on the opposite side of the first lens across the concave surface. In this case, it is possible to naturally observe external light across the parallel flat plate formed by the first lens and the second lens.

[0098] In a specific aspect, a coupling lens having positive refractive power is provided, and image light passes through the coupling lens when incident on the first prism from the display. In the case of directly forming a virtual image without forming an intermediate image, the refractive power can be ensured by the coupling lens, the first lens and the second reflecting member, and the increase in optical path length can be suppressed and the magnification can be ensured, thereby avoiding the enlargement of the optical system.

[0099] In a specific aspect, the first reflecting member includes a first supporting substrate in the form of a parallel flat plate and supporting the first optical functional layer, and is arranged in an inclined state opposite to the display, and the second reflecting member includes a second supporting substrate that is curved and has a uniform thickness and supports the second optical functional layer. In this case, the first reflecting member is arranged in an inclined state between the second reflecting member and the pupil position, the image light from the display is reflected in an oblique direction by the first reflecting member, and the image light from the first reflecting member is reflected by the second reflecting member, passes through the first reflecting member, and is incident on the pupil position.

[0100] In a specific aspect, the second supporting substrate supports the second optical functional layer on the inner surface facing the first reflecting member, or includes a pair of bonded substrate elements and supports the second optical functional layer between the pair of substrate elements.

[0101] In a specific aspect, the display comprises: a display element that emits image light; a polarizing plate that is arranged opposite to the display element; and a quarter-wave plate that is arranged opposite to the polarizing plate on the opposite side of the display element. Here, the display element emits image light including polarized light in one direction or two directions.

[0102] In a specific aspect, the display includes a display element that emits image light and a cholesteric liquid crystal element disposed opposite to the display element. Here, the display element is, for example, an organic EL element display that emits image light including polarized light in at least one direction.

[0103] In a specific aspect, the display comprises: a display element that emits image light as polarized light in a predetermined direction; and a quarter wavelength plate that is arranged opposite to the display element. Here, the display element is, for example, a liquid crystal element display that emits image light as polarized light in a predetermined direction.

[0104] An optical unit according to one aspect of the present invention comprises: a display that emits circularly polarized image light; a planar first reflecting component that reflects the image light in an oblique direction; and a second reflecting component that has a positive refractive power and reflects the image light reflected by the first reflecting component toward the first reflecting component, wherein the first reflecting component includes a first optical functional layer that is one of a cholesteric liquid crystal layer and a transmissive reflecting layer, and the second reflecting component includes a second optical functional layer that is the other of the cholesteric liquid crystal layer and the transmissive reflecting layer.

Claims

1. A virtual image display device, comprising: a display that emits circularly polarized image light; a planar first reflecting member that reflects the image light in an oblique direction; and a second reflecting member having a positive refractive power and reflecting the image light reflected by the first reflecting member toward the first reflecting member, The first reflecting member includes a first optical functional layer which is one of a cholesteric liquid crystal layer and a transmissive reflecting layer. The second reflecting member includes a second optical functional layer as the other of the cholesteric liquid crystal layer and the transmissive reflective layer.

2. The virtual image display device according to claim 1, wherein: The first reflecting member includes the transmissive reflecting layer as the first optical functional layer. The second reflecting member includes the cholesteric liquid crystal layer as the second optical functional layer.

3. The virtual image display device according to claim 1, wherein: The virtual image display device comprises: a first prism on which the image light from the display is incident; and a second prism which is joined to the first prism to form a parallel flat plate-shaped prism light guide component, The first reflecting member is provided at a junction between the first prism and the second prism.

4. The virtual image display device according to claim 3, wherein: The second reflecting member comprises: a plano-convex first lens having a flat surface disposed opposite to the outer surface of the first prism and a convex surface disposed on the opposite side of the first prism across the flat surface; and A second lens having a concave surface bonded to the convex surface via the second optical functional layer and a plane arranged parallel to the outer side surface of the first prism on the opposite side of the first lens via the concave surface, wherein the concave surface has a shape obtained by inverting the convex surface of the first lens.

5. The virtual image display device according to claim 4, wherein: The virtual image display device includes a coupling lens having a positive refractive power, and the image light passes through the coupling lens when entering the first prism from the display.

6. The virtual image display device according to claim 1, wherein: The first reflecting member includes a first supporting substrate, the first supporting substrate is in the form of a parallel plate and supports the first optical functional layer, and the first reflecting member is arranged in a state of being opposed to the display and tilted. The second reflecting member includes a second supporting substrate which is curved and has a uniform thickness and supports the second optical functional layer.

7. The virtual image display device according to claim 6, wherein: The second supporting substrate supports the second optical functional layer on an inner surface facing the first reflecting member, or includes a pair of bonded substrate elements and supports the second optical functional layer between the pair of substrate elements.

8. The virtual image display device according to claim 1, wherein: The display includes: a display element that emits the image light; a polarizing plate that is arranged to face the display element; and a quarter-wave plate that is arranged on the opposite side of the display element to face the polarizing plate.

9. The virtual image display device according to claim 1, wherein: The display includes: a display element that emits the image light; and a cholesteric liquid crystal element that is arranged to face the display element.

10. The virtual image display device according to claim 1, wherein: The display includes: a display element that emits the image light as polarized light in a predetermined direction; and a quarter wavelength plate that is arranged to face the display element.

11. An optical unit comprising: a display that emits circularly polarized image light; a planar first reflecting member that reflects the image light in an oblique direction; and a second reflecting member having a positive refractive power and reflecting the image light reflected by the first reflecting member toward the first reflecting member, The first reflecting member includes a first optical functional layer which is one of a cholesteric liquid crystal layer and a transmissive reflecting layer. The second reflecting member includes a second optical functional layer as the other of the cholesteric liquid crystal layer and the transmissive reflective layer.

Images