JP2024017556A - Virtual image display device and optical unit - Google Patents

Abstract

To prevent leakage of image light to a surface.SOLUTION: A virtual image display device 100 is provided, comprising a display element 11 acting as an image light generation device, a projection optical system 12 for receiving image light ML from the display element 11, and a partially transmissive mirror 123 for partially reflecting the image light ML from the projection optical system 12 toward a pupil position PP. The partially transmissive mirror 123 has a reflective polarizer 23p, and a reflective hologram 30p is provided on the outside of the partially transmissive mirror 123 at a distance.SELECTED DRAWING: Figure 2

Description

The present invention relates to a virtual image display device that enables observation of a virtual image, and more particularly to a virtual image display device and an optical unit that include a partially transmitting mirror.

2. Description of the Related Art Some virtual image display devices have a light-transmissive optical member placed in front of the eyes so that image light and external light can be observed simultaneously. For example, Patent Document 1 discloses a device that includes a prism member incorporating a transflective surface and a condensing reflection member that is an internal reflection type concave mirror (see Patent Document 1). In this device, the image light incident on the prism member is totally reflected and guided by the total reflection surface of the prism member toward the semi-transparent reflection surface, and the image light is focused by the semi-transmission reflection surface into a condenser placed in front of the prism member. It is described that the light is reflected toward a light reflecting member.

Japanese Patent Application Publication No. 2020-008749

In the virtual image display device of Patent Document 1, when a lens is used in the optical system, enlarging the area where light rays enter the pupil diameter requires increasing the size of the lens, resulting in an increase in the size of the optical system. Furthermore, in the virtual image display device of Patent Document 1, since the image light is emitted to the outside of the light collecting and reflecting member, the image light may leak from the light collecting and reflecting member to the outside, and there is a risk that the image being displayed can be seen from the outside. be.

A virtual image display device according to one aspect of the present invention includes an image light generation device, a projection optical system into which image light from the image light generation device is incident, and a projection optical system that partially reflects the image light from the projection optical system toward a pupil position. a partially transmitting mirror, the partially transmitting mirror has a reflective polarizer, and a reflective hologram is arranged spaced apart outside the partially transmitting mirror.

An optical unit according to one aspect of the present invention includes a projection optical system into which image light from an image light generation device is incident, and a partially transmitting mirror that partially reflects image light from the projection optical system toward a pupil position. The partially transmitting mirror has a reflective polarizer, and a reflective hologram is disposed apart from the partially transmitting mirror.

FIG. 2 is an external perspective view illustrating a state in which the virtual image display device according to the first embodiment is installed. FIG. 2 is a side sectional view illustrating the structure of a virtual image display device. FIG. 3 is a partially enlarged sectional view illustrating the periphery of a partially transmitting mirror and a cover member. FIG. 3 is a partially enlarged sectional view illustrating the periphery of a partially transmitting mirror and a cover member. FIG. 7 is a side sectional view illustrating the structure of a virtual image display device according to a second embodiment. FIG. 7 is a side sectional view illustrating the structure of a virtual image display device according to a third embodiment. FIG. 7 is an enlarged sectional view showing the partially transmitting mirror and cover member of FIG. 6; FIG. 7 is a side sectional view illustrating a virtual image display device according to a fourth embodiment.

[First embodiment]
Hereinafter, a virtual image display device according to a first embodiment of the present invention will be described with reference to FIGS. 1, 2, etc.

FIG. 1 is a diagram illustrating a state in which a head-mounted display (hereinafter also referred to as HMD) 200 is worn, and the HMD 200 allows an observer or wearer US wearing the HMD 200 to recognize an image as a virtual image. In FIG. 1 etc., X, Y, and Z are orthogonal coordinate systems, and the +X direction corresponds to the horizontal direction in which both eyes EY of the observer or wearer US wearing the HMD 200 or the virtual image display device 100 are lined up, The +Y direction corresponds to the upward direction perpendicular to the lateral direction in which both eyes EY are lined up for the wearer US, and the +Z direction corresponds to the front direction or frontal direction for the wearer US. The ±Y direction is parallel to the vertical axis or vertical direction.

The HMD 200 includes a first display device 100A for the right eye, a second display device 100B for the left eye, a pair of temple-shaped support devices 100C that support the display devices 100A and 100B, and a user terminal 90 that is an information terminal. Equipped with. The first display device 100A functions independently as a virtual image display device, and includes a display drive unit 102 disposed at the top, a combiner 103 shaped like a spectacle lens and covering the front of the eyes, and a front combiner 104 covering the combiner 103 from the front. configured. Similarly, the second display device 100B functions independently as a virtual image display device, and is composed of a display drive section 102 disposed at the top, a combiner 103 shaped like a spectacle lens that covers the front of the eyes, and a front combiner 104 that covers the combiner 103. be done. A combination of the pair of front combiners 104 is called a cover member 105. The cover member 105 is an integral member and is fixed to the display drive section 102. The support device 100C is a mounting member that is mounted on the head of the wearer US, and supports the upper end sides of the combiner 103 and the front combiner 104 via the display drive unit 102. The first display device 100A and the second display device 100B are optically reversed left and right, and a detailed explanation of the second display device 100B will be omitted.

FIG. 2 is a side sectional view illustrating the optical structure of the first display device 100A. The first display device 100A includes a display element 11, a bandpass filter 40, an imaging optical system 20, a hologram element 30, and a display control device 88. The imaging optical system 20 includes a projection lens 21, a prism mirror 22, and a see-through mirror 23. Of the imaging optical system 20, the projection lens 21 and the prism mirror 22 function as the projection optical system 12 into which the image light ML from the display element 11, which is an image light generation device, enters, and the see-through mirror 23 functions as the It functions as a partially transmitting mirror 123 that partially reflects the image light ML emitted from the optical system 12 toward the pupil position PP or the eye EY. The projection lens 21 and the prism mirror 22 that constitute the projection optical system 12 correspond to a first optical member and a second optical member, respectively, into which the image light or the image light ML is incident. Further, the display element 11, the projection lens 21, and the prism mirror 22 correspond to a part of the display drive unit 102 shown in FIG. The projection lens 21 and prism mirror 22 that constitute the projection optical system 12 are fixed in the case 51 in a mutually aligned state with the display element 11. The see-through mirror 23 corresponds to the combiner 103 shown in FIG. 1, that is, the rear combiner. The see-through mirror 23 has an outwardly convex outer shape, and its outer side is partially covered by a separately provided hologram element 30. Holographic element 30 corresponds to front combiner 104 shown in FIG. The bandpass filter 40 is arranged between the display element 11 and the imaging optical system 20, specifically, between the display element 11 and the projection lens 21. The case 51 is a housing or a support member, is made of a light-shielding material, and supports the display control device 88 that operates the display element 11. The case 51 has an opening 51a, and the opening 51a is closed by a transparent plate 53. The light-transmitting plate 53 enables the projection optical system 12 to emit the image light ML toward the outside of the case 51, and suppresses dust and moisture from entering the inside of the case 51.

In the first display device 100A, the display element 11 is a self-luminous image light generation device. The display element 11 is, for example, an organic EL (Organic Electro-Luminescence) display, and forms a color still image or moving image on a two-dimensional display surface 11a. The display element 11, which is an image light generation device, performs a display operation by being driven by a display control device 88, which is a control section. The display element 11 is not limited to an organic EL display, but can be replaced with a display device using an inorganic EL, an organic LED, an LED array, a laser array, a quantum dot light-emitting element, or the like. The display element 11 is not limited to a self-luminous image light generation device, but may be configured with an LCD or other light modulation element, and forms an image by illuminating the light modulation element with a light source such as a backlight. You can. As the display element 11, an LCOS (Liquid crystal on silicon, LCoS is a registered trademark), a digital micromirror device, or the like can be used instead of an LCD.

When the display element 11 is, for example, an LCD, the image light ML emitted from the display element 11 generally becomes polarized light. As described later, in this embodiment, the reflective polarizing film 23a of the see-through mirror 23 reflects S-polarized light, so the image light ML emitted from the display element 11 needs to be S-polarized light or include S-polarized light.

The bandpass filter 40 transmits light of a specific wavelength, and has a narrow transmission wavelength band. When the image light ML emitted from the display element 11 is monochromatic, light of a specific wavelength can be efficiently extracted. In the case of this embodiment, the bandpass filter 40 has a transmission wavelength band whose center wavelength is, for example, 633 nm. Note that the image light ML emitted from the display element 11 may have three colors, and in this case, the bandpass filter 40 has three transmission wavelength bands, specifically, red, green, and blue (RGB) transmission wavelength bands. Become something. The transmission wavelength bands of RGB are adjusted within the ranges of, for example, 625 to 780 nm, 500 to 565 nm, and 450 to 484 nm. The center wavelengths of the transmission wavelength band are, for example, 638 nm, 523 nm, and 449 nm.

The imaging optical system 20 is an off-axis optical system OS due to the fact that the see-through mirror 23 is a concave mirror. In the case of this embodiment, the projection lens 21, the prism mirror 22, and the see-through mirror 23 are arranged non-axially symmetrically and have non-axially symmetrical optical surfaces. In this imaging optical system 20, the optical axis AX is bent within an off-axis plane parallel to the YZ plane, so that optical elements 21, 22, and 23 are arranged along the off-axis plane. Specifically, on an off-axis plane parallel to the YZ plane, an optical path P1 from the projection lens 21 to the internal reflective surface 22b of the prism mirror 22, an optical path P2 from the internal reflective surface 22b to the see-through mirror 23, and an optical path P2 from the internal reflective surface 22b to the see-through mirror 23. The optical path P3 from to the pupil position PP is arranged to be turned back in two stages in a Z-shape. As a result, the normal line at the center of the see-through mirror 23 where the optical axis AX intersects forms an angle of about θ=40 to 50° with respect to the Z direction. In this imaging optical system 20, the optical paths P1 to P3 are folded back in two stages in a Z-shape, and since the optical paths P1 and P3 are relatively horizontal, the optical elements constituting the first display device 100A 21, 22, and 23 are arranged at different heights in the vertical direction, thereby preventing an increase in the width of the first display device 100A. Furthermore, by folding the optical path through reflection by the prism mirror 22 or the like, the imaging optical system 20 can be downsized in the vertical and front-back directions as well. Furthermore, since the inclination angle θ at the center of the see-through mirror 23 is 40 to 50°, if the inclination of the optical path P3 corresponding to the line of sight is constant, the inclination of the optical path P2 with respect to the Z axis will be from 70° to 90°. , it becomes easy to reduce the thickness of the virtual image display device 100 in the Z direction.

In the imaging optical system 20, the optical path P1 from the projection lens 21 to the internal reflection surface 22b of the prism mirror 22 extends slightly diagonally upward toward the rear with respect to the viewpoint or in a direction nearly parallel to the Z direction. There is. The optical path P2 from the internal reflection surface 22b to the see-through mirror 23 extends obliquely downward toward the front. When the horizontal plane direction (XZ plane) is used as a reference, the inclination of the optical path P2 is larger than the inclination of the optical path P1. The optical path P3 from the see-through mirror 23 to the pupil position PP extends toward the rear in a slightly diagonal upward direction or in a direction nearly parallel to the Z direction. In the illustrated example, the portion of the optical axis AX corresponding to the optical path P3 is approximately −10° toward the +Z direction, with downward direction being negative. That is, the partially transmitting mirror 123 reflects the image light ML so that the optical axis AX or the optical path P3 is directed upward at a predetermined angle, that is, about 10 degrees upward. As a result, the exit optical axis EX, which is an extension of the portion of the optical axis AX that corresponds to the optical path P3, extends downwardly by about 10 degrees with respect to the central axis HX that is parallel to the forward +Z direction. This is because the human line of sight is stabilized when the eyes are slightly lowered, tilted downward by about 10 degrees from the horizontal direction. Note that the central axis HX extending in the horizontal direction with respect to the pupil position PP is based on the assumption that the wearer US wearing the first display device 100A is relaxed in an upright position, facing forward, and gazing at the horizontal direction or the horizon line. It has become a thing.

Note that the overall optical path in the imaging optical system 20 is not limited to three optical paths P1, P2, and P3 forming a Z-shape as shown in the figure, but can include various optical paths including two or four or more optical paths. can be changed to something. In the illustrated example, the first optical path P1 and the last optical path P3 are closer to the horizontal than the intermediate optical path P2, but the angles of each optical path P1, P2, and P3 are also determined in consideration of the use of the virtual image display device 100, etc. It can be set to various things. However, it is generally desirable to set the final optical path P3 in consideration of the line of sight as described above. The attitude of the partially transmitting mirror 123 is affected by the angle setting of the intermediate optical path P2 and the angle setting of the final optical path P3, particularly in the central portion through which the optical axis AX passes.

Of the imaging optical system 20, the projection lens 21 includes a first lens 21o, a second lens 21p, and a third lens 21q. The projection lens 21 receives the image light ML emitted from the display element 11 and makes it enter the prism mirror 22 . The projection lens 21 condenses the image light ML emitted from the display element 11 into a nearly parallel beam. The optical surfaces of the first lens 21o, second lens 21p, and third lens 21q that constitute the projection lens 21, that is, the entrance surface and the exit surface, are free-form surfaces or aspherical surfaces, parallel to the YZ plane and intersecting the optical axis AX. With respect to the vertical direction, there is asymmetry across the optical axis AX, and with respect to the horizontal direction or the X direction, there is symmetry across the optical axis AX. The first lens 21o, the second lens 21p, and the third lens 21q are made of resin, for example, but may also be made of glass. An antireflection film can be formed on the optical surfaces of the first lens 21o, second lens 21p, and third lens 21q that constitute the projection lens 21.

The prism mirror 22 is an optical member having a refractive/reflective function and has a combined function of a mirror and a lens, and reflects the image light ML from the projection lens 21 while refracting it. The prism mirror 22 has an entrance surface 22a corresponding to an entrance section, an internal reflection surface 22b corresponding to a reflection section, and an exit surface 22c corresponding to an exit section. The prism mirror 22 emits the image light ML incident from the front so as to turn it back in a direction inclined downward with respect to the direction in which the direction of incidence is reversed (the direction of the light source as seen from the prism mirror 22). The entrance surface 22a, the internal reflection surface 22b, and the exit surface 22c, which are optical surfaces constituting the prism mirror 22, have asymmetrical properties across the optical axis AX with respect to the vertical direction parallel to the YZ plane and intersecting the optical axis AX. However, it has symmetry across the optical axis AX in the lateral direction or the X direction. The optical surfaces of the prism mirror 22, that is, the entrance surface 22a, the internal reflection surface 22b, and the exit surface 22c, are, for example, free-form surfaces. The entrance surface 22a, the internal reflection surface 22b, and the exit surface 22c are not limited to free-form surfaces, but may also be aspherical surfaces. The prism mirror 22 is made of resin, for example, but may also be made of glass. The internal reflection surface 22b is not limited to one that reflects the image light ML by total reflection, but may also be a reflection surface made of a metal film or a dielectric multilayer film. In this case, a reflective film made of a single layer or a multilayer film made of a metal such as Al or Ag is formed on the internal reflective surface 22b by vapor deposition, or a reflective film made of a sheet of metal is formed on the internal reflective surface 22b. Paste the membrane. Although detailed illustration is omitted, an antireflection film can be formed on the entrance surface 22a and the exit surface 22c.

The see-through mirror 23 is a curved plate-shaped reflective optical member that functions as a concave surface mirror, and reflects the image light ML from the prism mirror 22 while partially transmitting the external light OL. The see-through mirror 23 reflects the image light ML from the prism mirror 22 arranged in the exit area of the projection optical system 12 toward the pupil position PP. See-through mirror 23 has a reflective surface 23c and an outer surface 23o.

The see-through mirror 23 partially reflects the image light ML and magnifies an intermediate image formed on the light exit side of the prism mirror 22. The see-through mirror 23 is a concave mirror that covers the eye EY or the pupil position PP where the pupil is located, has a concave shape toward the pupil position PP, and has a convex shape toward the outside world. The pupil position PP or its aperture PPa is called an eye point or an eye box. The pupil position PP or the aperture PPa corresponds to the exit pupil EP on the exit side of the imaging optical system 20. The see-through mirror 23 is a collimator, and is a principal ray of the image light ML emitted from each point on the display surface 11a, which is an image that is once expanded by imaging near the exit side of the prism mirror 22 of the projection optical system 12. The chief ray of the light ML is converged on the pupil position PP. The see-through mirror 23 serves as a concave mirror and enables an enlarged view of an intermediate image (not shown) formed on the display element 11, which is an image light generating device, and re-imaged by the projection optical system 12. More specifically, the see-through mirror 23 functions similarly to a field lens, collimating the image light ML from each point of an intermediate image (not shown) formed after the output surface 22c of the prism mirror 22. The light is made to enter so as to be concentrated as a whole at the pupil position PP. The see-through mirror 23 is located between the intermediate image and the pupil position PP, and corresponds to the angle of view (the sum of the viewing angles in the upper, lower, left, and right directions with respect to the optical axis AX extending in the front direction of the eye EY). It is necessary to have a width larger than the effective area EA. In the see-through mirror 23, the outer area extending outside the effective area EA can have any surface shape as it does not directly affect image formation, but from the viewpoint of ensuring the appearance of a spectacle lens, It is desirable that the curvature be the same as the curvature of the surface shape of the outer edge of the area EA, or that it changes continuously from the outer edge.

The see-through mirror 23 is a semi-transmissive mirror plate having a structure in which a reflective polarizing film 23a is formed on the back surface of a plate-like body 23b. The back surface of the plate-shaped body 23b is a surface on the eye EY or pupil position PP side, and corresponds to the reflective surface 23c of the see-through mirror 23. The reflective surface 23c of the see-through mirror 23 has asymmetrical properties across the optical axis AX with respect to the vertical direction that is parallel to the YZ plane and intersects with the optical axis AX, and is symmetrical with respect to the horizontal direction or the X direction across the optical axis AX. has. The reflective surface 23c of the see-through mirror 23 is, for example, a free-form surface. The reflective surface 23c is not limited to a free-form surface, but may also be an aspherical surface. The reflective surface 23c needs to have an extent larger than the effective area EA. When the reflective surface 23c is formed in an outer area wider than the effective area EA, a difference in appearance is unlikely to occur between an external world image from behind the effective area EA and an external world image from behind the external area. .

The see-through mirror 23 reflects polarized light of the image light ML in a specific direction and transmits polarized light in a direction different from the specific direction. The reflective polarizing film 23a of the see-through mirror 23 reflects polarized light in a specific direction with a predetermined reflectance, and absorbs or transmits the remaining polarized light in the specific direction. Further, in the reflective polarizing film 23a, polarized light in a direction different from the specific direction is transmitted with a predetermined transmittance, and the remaining polarized light in a direction different from the specific direction is absorbed or reflected. Polarized light in a direction different from the specific direction that has passed through the see-through mirror 23 is reflected at a hologram element 30, which will be described later, and the reflected light is transmitted through the see-through mirror 23 at a predetermined transmittance. Further, the see-through mirror 23 transmits polarized light in a direction different from the specific direction out of the external light OL transmitted through the hologram element 30 at a predetermined transmittance. As a result, part of the image light ML reflected by the see-through mirror 23 or the hologram element 30 enters the pupil position PP. A part of the external light OL that has passed through the hologram element 30 and the see-through mirror 23 enters the pupil position PP.

Specifically, the reflective surface 23c or reflective polarizing film 23a of the see-through mirror 23 is formed of a polarizing film that reflects S-polarized light, and functions as a reflective polarizer 23p. The reflective polarizing film 23a has its polarization axis set in the vertical direction. In other words, the reflective polarizing film 23a has a reflection axis set in the horizontal direction, and efficiently reflects S-polarized light whose polarization direction is the ±X direction corresponding to the horizontal direction with little attenuation, and corresponds to the vertical direction. Most of the P-polarized light whose polarization direction is in the ±Y direction is transmitted. The transmission axis of the reflective polarizing film 23a is in the vertical direction, that is, the ±Y direction. As a result, the S component of the image light ML is reflected, and the P component is transmitted, thereby functioning like a half mirror with respect to the image light ML. On the other hand, when the external world light OL passes through a hologram element 30 (described later), the S-polarized light of the passed external world light OL is blocked by the see-through mirror 23, and the P-polarized light of the passed external world light OL passes through the see-through mirror 23. Therefore, see-through viewing of the outside world becomes possible, and a virtual image can be superimposed on the outside world image. At this time, if the plate-like body 23b that supports the reflective polarizing film 23a is thin to about several mm or less, the change in magnification of the external image can be suppressed to a small level. The plate-shaped body 23b, which is the base material of the see-through mirror 23, is made of resin, for example, but it can also be made of glass. The plate-like body 23b is made of the same material as the support plate 61 that supports it from the periphery, and has the same thickness as the support plate 61. The reflective polarizing film 23a is formed of, for example, a dielectric multilayer film composed of a plurality of dielectric layers with adjusted film thicknesses. The reflective polarizing film 23a can be formed by laminating layers, but it can also be formed by pasting a sheet-like reflective film. The laminated film of the reflective polarizing film 23a can be easily formed even if the plate-shaped body 23b has a curved surface. Further, the see-through mirror 23 may be formed by forming a thin aluminum microwire layer on the back surface of the plate-like body 23b as a reflective polarizer 23p, and using the reflective surface 23c as a wire grid surface. An antireflection film can be formed on the outer surface 23o of the plate-like body 23b.

In the above description, since the reflectance of S-polarized light is higher than that of P-polarized light, it is preferable to use a polarizing film that reflects S-polarized light as the reflective polarizing film 23a in terms of light utilization efficiency.

The hologram element 30 is a reflective holographic optical element that controls the traveling direction of light, and corresponds to a diffractive optical element. The hologram element 30 diffracts and reflects light incident on it within a predetermined angular range in a direction intended in terms of optical design, and transmits light incident on it outside the predetermined angular range. Specifically, the hologram element 30 reflects the P-polarized light of the image light ML that has passed through the see-through mirror 23 and transmits the external light OL. Therefore, in combination with the see-through mirror 23, see-through viewing of the outside world is possible, and a virtual image can be superimposed on the outside world image. Further, the hologram element 30 is an optical element equivalent to a concave mirror. The hologram element 30 collimates the incident light that has passed straight through the see-through mirror 23, and as a result of being spaced apart from the see-through mirror 23, it expands the area in which light rays enter the pupil in the vertical direction. In the illustrated example, the hologram element 30 has a convex shape toward the outside, similar to the see-through mirror 23. The hologram element 30 may be flat, but preferably has a curved surface. The hologram element 30 can control the phase by controlling the wavefront of light. The image light ML that enters the see-through mirror 23, that is, the image light ML that travels along the optical path P2, enters the see-through mirror 23 at an angle. In the see-through mirror 23, the image light ML traveling along the optical path P2 is inclined at a predetermined angle δ with respect to the exit optical axis EX, which is an extension of the portion corresponding to the optical path P3. As a result, the polarized light in the specific direction of the image light ML that has obliquely passed through the see-through mirror 23 is obliquely incident on the hologram element 30 at an incident angle substantially equal to the incident angle on the see-through mirror 23 . Thereby, it is possible to shift the image light ML downward, that is, to expand the pupil downward, in accordance with the distance between the see-through mirror 23 and the hologram element 30.

The hologram element 30 has a reflective layer 31c and an outer surface 31o. The reflective layer 31c of the hologram element 30 has asymmetry across the optical axis AX with respect to the vertical direction that is parallel to the YZ plane and intersects with the optical axis AX, and has symmetry across the optical axis AX with respect to the horizontal or X direction. has. The surface of the reflective layer 31c of the hologram element 30 is, for example, a free-form surface. The surface of the reflective layer 31c is not limited to a free-form surface, but may also be an aspherical surface.

The hologram element 30 has a structure in which a reflective hologram film 30a is formed on the back surface of a plate-shaped body 30b. The reflection hologram film 30a realizes control of the traveling direction of the light, that is, optical path control, by diffracting the light using interference fringes recorded in advance, and functions as the reflection hologram 30p. The reflective hologram film 30a is, for example, a volume hologram layer, in which a predetermined interference pattern is three-dimensionally recorded. The reflective hologram film 30a is a composite of diffraction patterns or stripes having a plurality of refractive indices.

The hologram element 30 is spaced apart from the reflective polarizing film 23a of the see-through mirror 23 or the reflective polarizer 23p. That is, the virtual image display device 100 includes the front combiner 104 provided with a reflective hologram film 30a as the reflective hologram 30p on the outside of the partially transmitting mirror 123 or the see-through mirror 23. The hologram element 30 or the reflection hologram 30p is a curved member that extends substantially parallel to the see-through mirror 23. This makes the distance between the see-through mirror 23 and the reflection hologram 30p substantially the same, making it easier to adjust the phase shift between the image light ML reflected by the see-through mirror 23 and the image light ML reflected by the reflection hologram 30p. . As shown in FIG. 3, the distance d between the see-through mirror 23 and the hologram element 30 is, for example, 3 to 5 mm. The plate-shaped body 30b that supports the reflective hologram film 30a is thin, about 1 mm or less, and suppresses changes in magnification of the external image to a small level. The plate-shaped body 30b, which is the base material of the hologram element 30, is made of resin, for example. The reflective hologram film 30a can be formed directly on the plate-like body 30b, but it is also possible to form the reflective hologram film 30a by forming a holographic recording material such as dichromate gelatin or silver salt emulsion on the film 30d. The formed film 30d can be attached onto the plate-like body 30b. The thickness of the reflective hologram film 30a is about 20 μm, and the thickness of the film 30d is about 100 μm. The total thickness of the hologram element 30 is, for example, about 1.1 mm. The interference pattern of the reflective hologram film 30a is formed using a technique such as scan exposure in which interference fringes are generated by scanning a laser beam, for example. Further, when the display element 11 is a color display, the reflection hologram film 30a can be a stack of three types of reflection holograms 30p exposed to each of RGB light. Further, the reflective hologram film 30a may be made of, for example, a photopolymer capable of multiple exposure. In this case, the reflective hologram film 30a includes interference fringes exposed with light having different wavelengths. An antireflection film can be formed on the outer surface 31o of the plate-shaped body 30b.

Generally, in order to enlarge the area where light rays enter the pupil, it is necessary to increase the size of the lens of the projection optical system 12. In the virtual image display device 100 of this embodiment, by using the reflection hologram 30p in the optical system, the area where light rays enter the pupil can be expanded without increasing the size of the lens. In other words, when the area where light rays enter the pupil is made to be the same size as the pupil expansion area, the projection lens 21 of the projection optical system 12 can be made smaller by using the reflection hologram 30p. In addition, while ensuring the light rays incident on the pupil, specifically, the image light ML and the external light OL, the reflective polarizer 23p and the reflective hologram 30p attenuate the light rays leaking to the outside, contributing to privacy. .

The reflection hologram 30p reflects a narrow band of light rays with respect to the image light ML that functions as a concave mirror. By providing the bandpass filter 40, the wavelength of the image light ML becomes a narrow band, and the polarized light of the image light ML that has passed through the reflective polarizer 23p of the see-through mirror 23 is efficiently reflected by the reflective hologram 30p, thereby improving privacy. can be more secure. Further, regarding light rays that enter the pupil from the outside, the light rays other than the band reflected by the reflection hologram 30p are transmitted, so that see-through properties can be ensured.

To explain the optical path, the image light ML from the display element 11 enters the bandpass filter 40, and the image light ML having a specific wavelength is transmitted therethrough. The image light ML that has passed through the bandpass filter 40 enters the projection lens 21 and is emitted from the projection lens 21 in a substantially collimated state. The image light ML that has passed through the projection lens 21 enters the prism mirror 22, passes through the entrance surface 22a while being refracted, is reflected by the internal reflection surface 22b with a high reflectance close to 100%, and is refracted again at the exit surface 22c. be done. The image light ML from the prism mirror 22 once forms an intermediate image, then enters the see-through mirror 23 and is reflected by the reflective surface 23c with a reflectance of about 90% or less. In FIG. 3, an example is given in which the image light ML incident on the see-through mirror 23 includes S-polarized light, and the reflective polarizer 23p of the see-through mirror 23 mainly reflects the S-polarized light. In this case, the reflective polarizer 23p mainly reflects S-polarized light and transmits P-polarized light. The S-polarized light of the image light ML reflected by the see-through mirror 23 enters the eye EY of the wearer US or the pupil position PP where the pupil is located. The P-polarized light of the image light ML that has passed through the see-through mirror 23 enters the hologram element 30 and is reflected by the reflective layer 31c. The P-polarized light of the image light ML reflected by the hologram element 30 passes through the see-through mirror 23 at a lower position than when traveling outward, and enters the eye EY of the wearer US or the pupil position PP where the pupil is located. . External light OL that has passed through the hologram element 30, the see-through mirror 23, and the support plate 61 around them also enters the pupil position PP. That is, the wearer US wearing the first display device 100A can observe a virtual image formed by the image light ML, superimposed on the external image. As shown in FIG. 4, when the reflective polarizer 23p of the see-through mirror 23 mainly reflects S-polarized light, the P-polarized light of the external light OL passes through the see-through mirror 23.

Table 1 below shows specific examples of the transmittance or reflectance of each member constituting the virtual image display device 100 of the first embodiment and the light utilization efficiency of the virtual image display device 100.
[Table 1]

As shown in Table 1, in the virtual image display device 100, the light use efficiency of S-polarized light is 4.5%, the light use efficiency of P-polarized light is 3.85%, and the overall light use efficiency is 8.35%. %.

The display control device 88 shown in FIG. 2 is a display control circuit, and outputs a drive signal corresponding to an image to the display element 11 to control the display operation of the display element 11. The display control device 88 includes, for example, an IF circuit, a signal processing circuit, etc., and causes the display element 11 to display a two-dimensional image according to image data or an image signal received from the outside. The display control device 88 may include a main board that controls the first display device 100A and the second display device 100B. The main board has an interface function that communicates with the user terminal 90 shown in FIG. It is possible to have an integrated function that links the display operations of . Note that the HMD 200 or the virtual image display device 100 that does not include the display control device 88 or the user terminal 90 is also a virtual image display device.

The virtual image display device 100 described above includes the image light generation device 11, the projection optical system 12 into which the image light ML from the image light generation device 11 enters, and the image light ML from the projection optical system 12 at the pupil position PP. The partially transmitting mirror 123 has a reflective polarizer 23p, and a reflective hologram 30p is arranged at a distance outside the partially transmitting mirror 123. .

In the virtual image display device 100, the reflection hologram 30p placed outside the reflection polarizer 23p of the partially transmitting mirror 123 can expand the area where light rays enter the pupil in the vertical direction. In other words, it is possible to enlarge the pupil in the vertical direction, and even if a lens is provided in the projection optical system 12, the lens, specifically, the projection lens 21 can be made smaller. Further, by filtering the light emitted from the partially transmitting mirror 123 by the reflection hologram 30p, it is possible to attenuate the image light ML leaking to the outside. As described above, it is possible to suppress the thickness of the optical system of the virtual image display device 100, to ensure the image light ML and external light OL entering the pupil, and to suppress the image light ML leaking to the outside, thereby ensuring privacy.

Furthermore, since the external light OL almost passes through the reflection hologram 30p, it is possible to prevent the external light pattern from being reflected on the surface of the partially transmitting mirror 123 and appearing to shine. Thereby, eye contact can be facilitated while preventing an unnatural appearance when the virtual image display device 100 is worn.

[Second embodiment]
A virtual image display device according to a second embodiment of the present invention will be described below. Note that the virtual image display device of the second embodiment is a partially modified version of the virtual image display device of the first embodiment, and a description of common parts will be omitted.

As shown in FIG. 5, the virtual image display device 100 of this embodiment does not have a bandpass filter, unlike the virtual image display device 100 of the first embodiment. That is, the virtual image display device 100 includes a display element 11, an imaging optical system 20, a hologram element 30, and a display control device 88.

To explain the optical path, the image light ML from the display element 11 enters the projection lens 21 and is emitted from the projection lens 21 in a substantially collimated state. The image light ML that has passed through the projection lens 21 enters the prism mirror 22, passes through the entrance surface 22a while being refracted, is reflected by the internal reflection surface 22b with a high reflectance close to 100%, and is refracted again at the exit surface 22c. be done. The image light ML from the prism mirror 22 once forms an intermediate image, then enters the see-through mirror 23 and is reflected by the reflective surface 23c with a reflectance of about 90% or less. When the image light ML includes S-polarized light and the reflective polarizer 23p of the see-through mirror 23 mainly reflects the S-polarized light, the reflective polarizer 23p mainly reflects the S-polarized light and transmits the P-polarized light. The S-polarized light of the image light ML reflected by the see-through mirror 23 enters the eye EY of the wearer US or the pupil position PP where the pupil is located. The P-polarized light of the image light ML that has passed through the see-through mirror 23 enters the hologram element 30 and is reflected by the reflective layer 31c. The P-polarized light of the image light ML reflected by the hologram element 30 passes through the see-through mirror 23 and enters the eye EY or pupil position PP of the wearer US where the pupil is located. External light OL that has passed through the hologram element 30, the see-through mirror 23, and the support plate 61 around them also enters the pupil position PP. In other words, the wearer US wearing the virtual image display device 100 can observe the virtual image formed by the image light ML, superimposed on the external image.

Table 2 below shows specific examples of the transmittance or reflectance of each member constituting the virtual image display device 100 of the second embodiment and the light utilization efficiency of the virtual image display device 100.
[Table 2]

As shown in Table 2, in the virtual image display device 100, the light use efficiency of S-polarized light is 45%, the light use efficiency of P-polarized light is 4.05%, and the overall light use efficiency is 49.1%. be.

[Third embodiment]
A virtual image display device according to a third embodiment of the present invention will be described below. Note that the virtual image display device of the third embodiment is a partially modified version of the virtual image display device of the first embodiment, and a description of common parts will be omitted.

As shown in FIG. 6, the virtual image display device 100 of this embodiment does not have a bandpass filter, unlike the virtual image display device 100 of the first embodiment. The virtual image display device 100 includes a display element 11, an imaging optical system 20, a hologram element 30, and a display control device 88.

The display element 11, which is the image light generation device of this embodiment, emits image light ML having polarization in a specific direction, specifically, S polarization. The display element 11 is composed of an LCD or other light modulation element, and forms an image by illuminating the light modulation element with a light source such as a backlight. As the display element 11, LCOS (Liquid crystal on silicon, LCoS is a registered trademark) can be used instead of LCD.

In the imaging optical system 20, the see-through mirror 23, which is a partially transmitting mirror 123, has a reflective polarizer 23p that partially reflects polarized light in a specific direction. The reflective polarizer 23p reflects, for example, 40 to 60%, preferably 50%, of polarized light in a specific direction. Specifically, the reflective polarizer 23p is a 50% S polarization reflector. That is, the reflective surface 23c of the see-through mirror 23 or the reflective polarizing film 23a reflects 50% of the S-polarized light of the image light ML. Further, in the virtual image display device 100, a λ/4 wavelength plate 70 is provided between the see-through mirror 23 and the hologram element 30. That is, the λ/4 wavelength plate 70 is placed on the outside side of the reflection polarizer 23p that functions as a 50% S polarization reflector, and the reflection hologram 30p is placed further on the outside side. In the illustration, the λ/4 wavelength plate 70 is a separate member from the reflective polarizer 23p and the reflective hologram 30p, but the λ/4 wavelength plate 70 may be attached to the reflective hologram 30p.

The λ/4 wavelength plate 70 provides a phase difference of λ/4 (90°) and converts linearly polarized light into circularly polarized light. The main axis of the λ/4 wavelength plate 70 is set, for example, between the −X direction and the +Y direction, and in a direction making an angle of 45° with respect to both directions. In this case, the reflective polarizer 23p and the λ/4 wavelength plate 70 function like a circular polarizing filter. The S-polarized light of the image light ML that has passed through the reflective polarizer 23p becomes circularly polarized light when it passes through the λ/4 wavelength plate 70. This circularly polarized light is reflected by the reflective layer 31c of the hologram element 30, passes through the λ/4 wavelength plate 70 again, and becomes P-polarized light. When external light OL enters from the outside of the see-through mirror 23, the external light OL that has passed through the hologram element 30 passes through the λ/4 wavelength plate 70, and then through the reflective polarizer 23p of the see-through mirror 23. Only polarized light is available.

To explain the optical path, the image light ML from the display element 11 enters the projection lens 21 and is emitted from the projection lens 21 in a substantially collimated state. The image light ML that has passed through the projection lens 21 enters the prism mirror 22, passes through the entrance surface 22a while being refracted, is reflected by the internal reflection surface 22b with a high reflectance close to 100%, and is refracted again at the exit surface 22c. be done. The image light ML from the prism mirror 22 once forms an intermediate image, then enters the see-through mirror 23 and is reflected by the reflective surface 23c with a reflectance of about 50%. In FIG. 7, an example is given in which the image light ML incident on the see-through mirror 23 has S-polarized light, and the reflective polarizer 23p of the see-through mirror 23 reflects 50% of the S-polarized light. In this case, 50% of the S-polarized light is reflected and the remaining S-polarized light is transmitted. The S-polarized light of the image light ML reflected by the see-through mirror 23 enters the eye EY of the wearer US or the pupil position PP where the pupil is located. The S-polarized light of the image light ML that has passed through the see-through mirror 23 enters the λ/4 wavelength plate 70 and becomes circularly polarized light. Thereafter, the circularly polarized light enters the hologram element 30 and is reflected by the reflective layer 31c. The circularly polarized light reflected by the hologram element 30 enters the λ/4 wavelength plate 70 again and becomes P-polarized light. The P-polarized light that has passed through the λ/4 wavelength plate 70 efficiently passes through the see-through mirror 23 and enters the eye EY of the wearer US or the pupil position PP where the pupil is located. External light OL that has passed through the hologram element 30, the see-through mirror 23, and the support plate 61 around them also enters the pupil position PP. In other words, the wearer US wearing the virtual image display device 100 can observe the virtual image formed by the image light ML, superimposed on the external image.

Table 3 below shows specific examples of the transmittance or reflectance of each member constituting the virtual image display device 100 of the third embodiment and the light utilization efficiency of the virtual image display device 100.
[Table 3]

As shown in Table 3, in the virtual image display device 100, the light use efficiency of S-polarized light is 50%, the light use efficiency of P-polarized light is 3.5%, and the overall light use efficiency is 53.5%. be.

In the above description, the display element 11 may be configured to emit P-polarized light, and in this case, the see-through mirror 23 is a 50% P-polarized light reflecting plate as a reflective polarizer 23p. In this case, the light beam that passes through the see-through mirror 23, is reflected by the reflection hologram 30p, passes through the see-through mirror 23 again, and enters the pupil position PP becomes S-polarized light.

[Fourth embodiment]
A virtual image display device according to a fourth embodiment of the present invention will be described below. Note that the virtual image display device of the fourth embodiment is a partial modification of the virtual image display device of the first embodiment, and a description of common parts will be omitted.

As shown in FIG. 8, the virtual image display device 100 of this embodiment does not have a bandpass filter, unlike the virtual image display device 100 of the first embodiment. The virtual image display device 100 includes a display element 11, an imaging optical system 20, a hologram element 30, and a display control device 88.

The display element 11, which is the image light generation device of this embodiment, includes a laser light source 13 and a MEMS mirror 14. When a single wavelength light source such as the laser light source 13 is used as the light source of the display element 11, the same wavelength as the laser light source 13 is used as the wavelength reflected by the reflection hologram 30p. Thereby, in the reflection hologram 30p, it is possible to further attenuate the light rays leaking to the outside. It is preferable to provide a lens for enlarging the image in the depth direction on the exit side of the MEMS mirror 14. Note that a backlight, a digital micromirror device, or the like may be used instead of the MEMS mirror 14. Further, in the virtual image display device 100, a λ/4 wavelength plate 170 is provided between the display element 11 and the imaging optical system 20. Specifically, a λ/4 wavelength plate 170 is arranged between the MEMS mirror 14 of the display element 11 and the projection lens 21 of the imaging optical system 20.

Further, in the virtual image display device 100, the see-through mirror 23, which is a partially transmitting mirror 123, serves as a reflective polarizer 23p that reflects most of the S-polarized light, for example, 90% S-polarized light, as in the first and second embodiments. It is a board.

To explain the optical path, in the display element 11, the image light ML emitted from the laser light source 13 is angled by the MEMS mirror 14, passes through the λ/4 wavelength plate 170, and becomes circularly polarized light. The circularly polarized light as the image light ML enters the projection lens 21 and exits from the projection lens 21. The image light ML that has passed through the projection lens 21 enters the prism mirror 22, passes through the entrance surface 22a while being refracted, is reflected by the internal reflection surface 22b with a high reflectance close to 100%, and is refracted again at the exit surface 22c. be done. The image light ML from the prism mirror 22 once forms an intermediate image, then enters the see-through mirror 23 and is reflected by the reflective surface 23c with a reflectance of about 90% or less. At this time, mainly S-polarized light is reflected and P-polarized light is transmitted. The S-polarized light of the image light ML reflected by the see-through mirror 23 enters the eye EY of the wearer US or the pupil position PP where the pupil is located. The P-polarized light of the image light ML that has passed through the see-through mirror 23 enters the hologram element 30 and is reflected by the reflective layer 31c. The P-polarized light of the image light ML reflected by the hologram element 30 passes through the see-through mirror 23 and enters the eye EY or pupil position PP of the wearer US where the pupil is located. External light OL that has passed through the hologram element 30, the see-through mirror 23, and the support plate 61 around them also enters the pupil position PP. In other words, the wearer US wearing the virtual image display device 100 can observe the virtual image formed by the image light ML, superimposed on the external image.

Table 4 below shows specific examples of the transmittance or reflectance of each member constituting the virtual image display device 100 of the fourth embodiment and the light utilization efficiency of the virtual image display device 100.
[Table 4]

As shown in Table 4, in the virtual image display device 100, the light use efficiency of S-polarized light is 45%, the light use efficiency of P-polarized light is 38.5%, and the overall light use efficiency is 83.5%. be.

In the virtual image display device 100 described above, by matching the wavelength used by the laser light source 13 with the wavelength band reflected by the reflection hologram 30p, it is possible to reduce the number of light rays that pass through the reflection hologram 30p and increase light utilization efficiency.

[Other variations]
Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments, and can be implemented in various forms without departing from the gist thereof. Modifications such as the following are also possible.

The see-through mirror 23 is not limited to the reflective polarizer 23p that reflects S-polarized light, but may also be a reflective polarizer 23p that reflects P-polarized light. In this case, in the see-through mirror 23, the P polarized light of the image light ML is reflected and the S polarized light is transmitted. The light beam that passes through the see-through mirror 23, is reflected by the reflection hologram 30p, passes through the see-through mirror 23 again, and enters the pupil position PP becomes S-polarized light.

The virtual image display device 100 may include a lens on the exit side of the prism mirror 22.

In the virtual image display device 100 of the first embodiment, the bandpass filter 40 may be provided on the exit side of the prism mirror 22 of the projection optical system 12.

The virtual image display device 100 may include a laterally asymmetric imaging optical system. In this case, the imaging optical system includes, for example, a projection lens and a light guiding member, and the image light becomes an optical path extending in the horizontal direction while being reflected.

The above description assumes that the virtual image display device 100 is used while being worn on the head, but the virtual image display device 100 can also be used as a handheld display that is viewed like binoculars without being worn on the head. . That is, in the present invention, the head-mounted display also includes a handheld display.

A virtual image display device in a specific embodiment includes an image light generation device, a projection optical system into which image light from the image light generation device is incident, and a projection optical system that partially reflects the image light from the projection optical system toward a pupil position. A partially transmitting mirror, the partially transmitting mirror has a reflective polarizer, and a reflective hologram is arranged spaced apart outside the partially transmitting mirror.

In the above virtual image display device, the area where light rays enter the pupil in the vertical direction can be expanded by the reflection hologram placed outside the reflection polarizer of the partially transmitting mirror. In other words, it is possible to enlarge the pupil in the vertical direction, and even if a lens is provided in the projection optical system, the lens can be made smaller. Further, by using the reflection hologram, the image light leaking to the outside can be attenuated by filtering the light emitted from the partially transmitting mirror with the reflection hologram.

In a specific aspect, the reflective polarizer is a reflective polarizing film provided inside a base material. In this case, the partially transmitting mirror can reflect polarized light in a specific direction out of the image light without wasting it.

In a specific aspect, a bandpass filter is disposed between the image light generating device and the reflective polarizer. In this case, the wavelength of the image light becomes a narrow band, and the polarized light of the image light that has passed through the reflective polarizer of the partially transmitting mirror is efficiently reflected by the reflective hologram, making it possible to further ensure privacy.

In a specific aspect, the bandpass filter is placed between the image light generation device and the projection optical system. In this case, if the image light emitted from the image light generation device is monochromatic, light of a specific wavelength can be efficiently extracted.

In a specific aspect, the image light generation device emits image light including polarized light in a specific direction, and the reflective polarizer is a reflective polarizer that polarizes 50% of the light in the specific direction; A λ/4 wavelength plate is placed between the reflection hologram and the reflection hologram. In this case, in the optical path that passes through the reflective polarizer, is reflected by the reflective hologram, and passes through the reflective polarizer again, the light that has passed through the λ/4 wavelength plate twice is polarized in a direction other than the specific direction. This allows the efficiency of light use to be increased.

In a specific aspect, the image light generation device includes a laser light source, and a λ/4 wavelength plate is disposed between the laser light source and a reflective polarizer. In this case, by matching the wavelength used by the laser light source with the wavelength band reflected by the reflection hologram, it is possible to reduce the number of light rays that pass through the reflection hologram and increase light utilization efficiency.

In a specific aspect, the partially transmitting mirror is a concave mirror. In this case, the image formed by the image light generation device or the image re-imaged by the projection optical system can be viewed magnified by the concave mirror.

In a specific aspect, the reflection hologram is a curved member that extends substantially parallel to the partially transmitting mirror. In this case, the distance between the partially transmitting mirror and the reflective hologram is approximately the same, and the phase shift between the image light reflected by the partially transmitting mirror and the image light reflected by the reflective hologram can be easily adjusted.

In a specific aspect, the projection optical system includes a first optical member that collects image light and a second optical member that reflects image light from the first optical member. In this case, the optical system can be easily miniaturized by folding the optical path due to reflection.

In a specific aspect, the second optical member includes an entrance part into which the image light enters, an exit part through which the incident image light exits toward the reflective member, and an exit part through which the image light entered from the entrance part goes toward the exit part. It has a reflective part that is reflected.

The optical unit in a specific embodiment includes a projection optical system into which the image light from the image light generation device is incident, and a partially transmitting mirror that partially reflects the image light from the projection optical system toward the pupil position. , the partially transmitting mirror has a reflective polarizer, and a reflective hologram is placed spaced apart outside the partially transmitting mirror.

In the above optical unit, the area where light rays enter the pupil in the vertical direction can be expanded by the reflection hologram placed outside the reflection polarizer of the partially transmitting mirror. Further, by using the reflection hologram, the image light leaking to the outside can be attenuated by filtering the light emitted from the partially transmitting mirror with the reflection hologram.

DESCRIPTION OF SYMBOLS 11... Display element, 12... Projection optical system, 13... Laser light source, 14... MEMS mirror, 20... Imaging optical system, 21... Projection lens, 22... Prism mirror, 22a... Incident surface, 22b... Internal reflection surface, 22c ... Output surface, 23... See-through mirror, 23a... Reflective polarizing film, 23c... Reflective surface, 23o... Outer surface, 23p... Reflective polarizer, 30... Hologram element, 30a... Reflective hologram film, 30p... Reflective hologram , 31c...Reflection layer, 31o...Outer surface, 40...Band pass filter, 51...Case, 70, 170...λ/4 wavelength plate, 88...Display control device, 100...Virtual image display device, 100C...Support device, 102... Display drive unit, 103...combiner, 104...front combiner, 123...partially transmitting mirror, AX...optical axis, EY...eye, ML...image light, OL...external light, OS...off-axis optical system, P1, P2, P3 ...Optical path, PP...pupil position, US...wearer

Claims (11)

an image light generating device;
a projection optical system into which image light from the image light generation device is incident;
a partially transmitting mirror that partially reflects the image light from the projection optical system toward a pupil position;
The partially transmitting mirror has a reflective polarizer,
A virtual image display device in which a reflection hologram is placed spaced apart from the partially transmitting mirror. The virtual image display device according to claim 1, wherein the reflective polarizer is a reflective polarizing film provided inside a base material. The virtual image display device according to claim 1, wherein a bandpass filter is disposed between the image light generation device and the reflective polarizer. The virtual image display device according to claim 3, wherein the bandpass filter is disposed between the image light generation device and the projection optical system. The image light generation device emits image light including polarized light in a specific direction,
The reflective polarizer is a reflective polarizer that partially reflects polarized light in the specific direction,
The virtual image display device according to claim 1, further comprising a λ/4 wavelength plate disposed between the reflective polarizer and the reflective hologram. The image light generation device has a laser light source,
The virtual image display device according to claim 1, further comprising a λ/4 wavelength plate disposed between the laser light source and the reflective polarizer. The virtual image display device according to claim 1, wherein the partially transmitting mirror is a concave mirror. The virtual image display device according to claim 1, wherein the reflection hologram is a curved member extending substantially parallel to the partially transmitting mirror. The virtual image display device according to claim 1, wherein the projection optical system includes a first optical member that collects the image light and a second optical member that reflects the image light from the first optical member. The second optical member includes an entrance portion into which the image light is incident, an exit portion through which the image light that has entered is directed toward the reflective member, and an exit portion through which the image light that has entered from the entrance portion is directed toward the exit portion. 10. The virtual image display device according to claim 9, further comprising: a reflective portion that is reflected by a reflective portion. a projection optical system into which image light from the image light generation device is incident;
a partially transmitting mirror that partially reflects the image light from the projection optical system toward a pupil position;
The partially transmitting mirror has a reflective polarizer,
An optical unit in which a reflection hologram is arranged spaced apart from the partially transmitting mirror.

Images