Virtual image display device

Abstract

To increase see-through transmittance in an image display area.SOLUTION: A virtual image display device 100A comprises, in order from the outside, a light guide member 21 that propagates illumination light IL from a light source 10, a scattering member 12 that is provided on the light guide member 21 and has a transmission area 12a and a scattering area 12b, a transmission type liquid crystal panel 22 that is in a display state or a non-display state; a switching 1 / 2 wavelength plate 23 that switches a polarization direction of incident light to a first direction and a second direction intersecting each other, and a polarizing lens 50 that has refractive power to form polarized light in the first direction as a virtual image and passes polarized light in the second direction. The transmission area 12a is arranged at a position facing one of pixels and sub-pixels of the transmission type liquid crystal panel 22. The switching 1 / 2 wavelength plate 23 makes video light ML enter the polarizing lens 50 as the polarized light in the first direction when the transmission type liquid crystal panel is in the display state, and makes external light OL enter the polarizing lens 50 as the polarized light in the second direction when the transmission type liquid crystal panel is in the non-display state.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a virtual image display device that enables observation of a virtual image, and more particularly to a see-through type virtual image display device that enables visual recognition of an external image.

Background Art

[0002] As a see-through type virtual image display device that enables visual recognition of the outside world, there is known a liquid crystal panel having an image display area and a transparent display area formed so as to surround the image display area, and a light guide plate that guides backlight light incident from a light source to an end portion. The light guide plate includes a light emitting area that irradiates the backlight light to the image display area of the liquid crystal panel and a light transmission area that transmits ambient light (Patent Document 1). In this virtual image display device, ambient light reaches the observer from the light transmission area of the light guide plate and the transparent display area of the liquid crystal panel, and during a period when the backlight light is not irradiated to the image display area, the ambient light passes through the light emitting area of the light guide plate and the image display area of the liquid crystal panel and reaches the observer. With such a configuration, a see-through display in which video light and ambient light are superimposed is realized.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above device, processing such as dot formation and scattering material application is performed on the light emitting area of the light guide plate, and the ambient light passing through the image display area of the liquid crystal panel passes through the processed light emitting area. Therefore, the see-through transmittance in the vicinity of the center of the visual field corresponding to the image display area decreases. In order to realize a see-through display with a high see-through transmittance in the vicinity of the center of the visual field, an optical system or the like with a high see-through transmittance is separately required, which leads to an increase in size.

Means for Solving the Problem

[0005] The virtual image display device according to one aspect of the present invention includes, in order from the outside world, a light guide member that propagates illumination light from a light source, a scattering member provided on the light guide member and having a transmission region and a scattering region, a transmissive liquid crystal panel that becomes a display state and a non-display state, a switching 1 / 2 wavelength plate that switches the polarization direction of incident light to a first direction and a second direction that intersect each other, and a polarization lens that has a refractive power to form an image of the polarization in the first direction as a virtual image and allows the polarization in the second direction to pass through. The transmission region is disposed at a position facing either a pixel or a sub-pixel of the transmissive liquid crystal panel. The switching 1 / 2 wavelength plate causes video light to enter the polarization lens as polarization in the first direction in the display state, and causes external light to enter the polarization lens as polarization in the second direction in the non-display state.

Brief Description of the Drawings

[0006]

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Embodiments for Carrying Out the Invention

[0007] 〔First Embodiment〕 Hereinafter, with reference to FIGS. 1 to 6, the virtual image display device according to the first embodiment of the present invention will be described.

[0008] FIG. 1 is a perspective view for explaining the wearing state of a head-mounted display, that is, a head-mounted display device 200. The head-mounted display device (hereinafter, also referred to as HMD) 200 is a binocular display device 201, and causes an observer or wearer US wearing this to recognize an image as a virtual image. In FIG. 1 and the like, X, Y, and Z are a rectangular coordinate system, the +X direction corresponds to the horizontal direction in which both 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 horizontal direction in which both eyes EY are arranged for the wearer US, and the +Z direction corresponds to the front direction or the front direction for the wearer US. The ±Y direction is parallel to the vertical axis or the vertical direction.

[0009] The HMD200 includes a first virtual image display device 100A for the right eye, a second virtual image display device 100B for the left eye, a pair of temples 100C that support the virtual image display devices 100A and 100B, and a user terminal 90 that is an information terminal. The first virtual image display device 100A is composed of a first display driving unit 102a disposed at the upper part, a first display optical system 103a that covers in front of the eyes, and a light transmission cover 104a that covers the first display optical system 103a on the outside or front side. The second virtual image display device 100B is composed of a second display driving unit 102b disposed at the upper part, a second display optical system 103b that covers in front of the eyes, and a light transmission cover 104b that covers the second display optical system 103b on the outside or front side. The HMD200 combining the first virtual image display device 100A and the second virtual image display device 100B is also a virtual image display device in a broad sense. The pair of temples 100C is a wearing member or support device 106 that is worn on the head of the wearer US, and supports the upper end sides of the pair of display optical systems 103a and 103b and the upper end sides of the pair of light transmission covers 104a and 104b through the display driving units 102a and 102b that are integrated in appearance. The combination of the pair of display driving units 102a and 102b is called a driving device 102. The combination of the pair of light transmission covers 104a and 104b is called a shade 104.

[0010] FIG. 2 is a perspective view for explaining the structure of the first display optical system 103a. The first display optical system 103a includes a light source 10 that generates three-color light as illumination light in a time-division manner, a plate-shaped composite display member 20 that forms a two-dimensional image and emits image light ML, and a polarization lens 50 that functions as a lens with respect to the image light ML. The light source 10 is also a part of the first display driving unit 102a shown in FIG. 1, and is arranged in the vicinity above the upper side of the light guide member 21 so as to supply illumination light from the upper end side to the light guide member 21, which will be described later, among the composite display members 20. The light source 10 and the composite display member 20 are driven by a drive circuit 81 of a control device 80 incorporated in the first display driving unit 102a to operate, and simultaneously realize the observation of a virtual image by the image light ML and see-through vision of the outside world. That is, the drive circuit 81 operates by synchronizing the light source 10, the transmissive liquid crystal panel 22, and the switching 1 / 2 wavelength plate 23. The composite display member 20 and the polarization lens 50 are arranged at a distance in the optical axis AX direction. In the first display optical system 103a, the distance between the eye EY and the polarization lens 50 is, for example, about 10 mm to 20 mm. Also, the distance between the composite display member 20 and the polarization lens 50 is, for example, about 3 mm to 25 mm.

[0011] The light source 10 includes an R light emitting element 10r that generates red light, a G light emitting element 10g that generates green light, and a B light emitting element 10b that generates blue light. The R light emitting element 10r, the G light emitting element 10g, and the B light emitting element 10b are self-luminous elements, and may be, for example, light emitting diodes such as organic light emitting diodes (OLEDs) and micro light emitting diodes (μLEDs) formed of inorganic materials. The R light emitting element 10r, the G light emitting element 10g, and the B light emitting element 10b are not limited to being incorporated alone. That is, the light source 10 is a combination of one or more R light emitting elements 10r, one or more G light emitting elements 10g, and one or more B light emitting elements 10b. A multiplexer / demultiplexer including a beam splitter can be incorporated between the light source 10 and the light guide member 21 of the composite display member 20 to assist in the diffusion of illumination light.

[0012] The composite display member 20 is a plate-shaped member extending along the XY plane perpendicular to the optical axis AX, and includes, in order from the outside world, a light guide member 21, a transmissive liquid crystal panel 22, and a switching 1 / 2 wavelength plate 23. The composite display member 20 is a plate-shaped member as a whole in which the light guide member 21, the transmissive liquid crystal panel 22, and the switching 1 / 2 wavelength plate 23 are laminated, and has a structure integrated by a frame body (not shown). Here, the light guide member 21, the transmissive liquid crystal panel 22, and the switching 1 / 2 wavelength plate 23 are fixed to each other in a state of being arranged in the vicinity with a predetermined interval. The transmissive liquid crystal panel 22 includes a plurality of pixels PX (see FIG. 3) arranged in a matrix along the XY plane.

[0013] The polarizing lens 50 is disposed on the front side of the composite display member 20, that is, the -Z side, and covers the front of the eyes. More specifically, the polarizing lens 50 is disposed on the opposite side of the transmissive liquid crystal panel 22 facing the switching 1 / 2 wavelength plate 23 in the composite display member 20. The polarizing lens 50 is a plate-shaped member extending along the XY plane. The action of the polarizing lens 50 varies depending on the polarization direction of the incident light. The polarizing lens 50 functions as a lens with respect to the video light ML emitted from the composite display member 20. That is, the polarizing lens 50 comprehensively forms an image of a plurality of pixels constituting the transmissive liquid crystal panel 22, and enables the image formed on the transmissive liquid crystal panel 22 to be observed as a virtual image. On the other hand, the polarizing lens 50 functions as a parallel plate with respect to the external light OL passing through the composite display member 20. Specifically, the polarizing lens 50 is a liquid crystal lens, and includes a plurality of circular annular portions RA having different refractive index states. A group of annular portions RA are symmetrically and concentrically arranged around the optical axis AX. Among the group of annular portions RA, the peripheral annular portion RA away from the optical axis AX has a narrower radial width centered on the optical axis AX than the central annular portion RA through which the optical axis AX passes. That is, the radial width of the annular portion RA becomes narrower toward the periphery.

[0014] The second display optical system 103b is optically identical to the first display optical system 103a, or is obtained by horizontally inverting the first display optical system 103a, and a detailed description thereof is omitted.

[0015] Referring to FIG. 3, the light source 10 generates, as illumination light IL, three-color illumination lights ILr, ILg, and ILb in a time-division manner, and supplies the three-color illumination lights ILr, ILg, and ILb to the light guide member 21 of the composite display member 20. The three-color illumination lights IL are selected so as to become white light when superimposed.

[0016] The light guide member 21 is provided with a scattering member 12 attached to the light guide plate 11. In the present embodiment, the scattering member 12 is formed by processing the surface of the light guide plate 11 and is integrated with the light guide plate 11. The illumination lights ILr, ILg, and ILb from the light source 10 are coupled into the light guide plate 11 from the upper end of the light guide plate 11. The light guide plate 11 propagates the incident illumination lights ILr, ILg, and ILb from the light source 10 downward. Further, the light guide plate 11 allows the external light OL to pass through and permits its passage. The light guide plate 11 has a thickness of, for example, about 0.5 mm. The light guide plate 11 is formed of a plastic, glass, or the like having light transmissivity.

[0017] The light guide plate 11 is formed of a flat plate having light transmissivity and has a pair of planes 11a and 11b. A scattering member 12 is provided on the plane 11a on the front side or the outside world side of the light guide plate 11. That is, the scattering member 12 is disposed on the plane 11a, which is the surface of the light guide plate 11 on the opposite side of the transmissive liquid crystal panel 22. By providing the scattering member 12 on the plane 11a on the outside world side of the light guide plate 11, the emission angle of the scattered light can be loosened, and it becomes easier to control the scattering angle while facilitating the production of the scattering member 12.

[0018] FIG. 4 is a conceptual plan view for explaining the scattering member 12. In FIG. 4, the scattering member 12 corresponding to the pixel PX of the transmissive liquid crystal panel 22 (see FIG. 3) is shown. The scattering member 12 is provided in a light guide member 21 including a light guide plate 11. The scattering member 12 has a transmission region 12a and a scattering region 12b disposed around the transmission region 12a. In the entire light guide member 21, a plurality of repeating sections 12c each including a transmission region 12a and a scattering region 12b as a set are two-dimensionally arranged. In the present embodiment, the scattering member 12 indicates one repeating section 12c or an aggregate of a plurality of repeating sections 12c. The repeating section 12c has a quadrangular contour in a plan view, but its shape can be appropriately changed. Also, there may be a gap between adjacent repeating sections 12c. The repeating section 12c may be arranged in units of pixels PX or in units of sub-pixels. In each repeating section 12c, the arrangement, area, etc. of the transmission region 12a and the scattering region 12b may be the same or different.

[0019] The transmission region 12a transmits external light OL. The scattering region 12b scatters the illumination light IL (ILr, ILg, ILb) and emits it outside the light guide plate 11. Thereby, the scattering member 12 creates a transparent state in which the external light OL is transmitted and allowed to pass through by the transmission region 12a, and a scattering state in which the illumination light IL is emitted outside the light guide plate 11 by the scattering region 12b. That is, the scattering member 12 can simultaneously create a scattering state and a transparent state, and can separate and emit the illumination light IL and the external light OL. The display switching between the video light ML formed by the illumination light IL and the external light OL is performed by turning on and off the switching 1 / 2 wavelength plate 23.

[0020] The transmission region 12a is disposed at a position facing the pixel PX of the transmissive liquid crystal panel 22. That is, the transmission region 12a corresponds to the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22. In the present embodiment, the transmission region 12a is the plane 11a of the light guide plate 11 and has a smooth surface. The transmission region 12a has a contour such as a circle, an ellipse, a quadrangle, a polygon, etc. in a plan view.

[0021] The scattering region 12b is partially arranged on the light guide plate 11 in pixel PX or sub-pixel units in the repeating section 12c. The scattering region 12b is arranged so as to surround the transmission region 12a. Specifically, the scattering region 12b is disposed around the transmission region 12a at a position corresponding to the black matrix 35 of the transmissive liquid crystal panel 22. The shape of the scattering region 12b is determined by the contours of the repeating section 12c and the transmission region 12a. In the illustrated example, the scattering region 12b has a quadrangular outer shape and a shape with a circular opening in the central portion in plan view. If the contour of the transmission region 12a is quadrangular, the scattering region 12b can have a shape close to the black matrix 35. The repeating section 12c may partially include those that do not have the transmission region 12a, that is, those in which the entire repeating section 12c is the scattering region 12b.

[0022] When giving priority to the video light ML, the scattering member 12 makes the area of the transmission region 12a smaller than the size of the opening OP. Also, when giving priority to the external light OL, the scattering member 12 increases the area of the transmission region 12a, for example, to be substantially the same size as the opening OP.

[0023] The scattering region 12b has a nanostructure NS. The illumination light IL, which is the scattered light reflected by the scattering region 12b, is emitted by the nanostructure NS in the direction of the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22. The scattering state in the scattering region 12b may be Lambertian scattering or scattering with directivity. The nanostructure NS can control the scattering direction and scattering angle of the illumination light IL so that a large amount of light can be diffracted at a predetermined location. By condensing the illumination light IL as scattered light with directivity onto the opening OP of the transmissive liquid crystal panel 22, the light utilization efficiency can be increased.

[0024] The scattering member 12 is formed of glass or plastic, like the light guide plate 11 which is the base material. The scattering member 12 has the same refractive index as the light guide plate 11. The nanostructure NS is formed by nanoimprint lithography, photolithography, or the like.

[0025] Returning to FIG. 3, the transmissive liquid crystal panel 22 is disposed on the face side, i.e., the -Z side, facing the light guide plate 11. The transmissive liquid crystal panel 22 includes a liquid crystal modulation member 14 and a pair of polarizing plates 15 and 16 sandwiching the liquid crystal modulation member 14. In this case, the transmissive liquid crystal panel 22 or the liquid crystal modulation member 14 is a modulation element made of, for example, an IPS (in plane switching) type liquid crystal or the like and operates in units of pixels PX. The pixel PX has no filter and is colorless. In the transmissive liquid crystal panel 22, the size of the region where the pixel PX is formed is about 1 to 2 inches, and the number of pixels is about 2K to 4K. The liquid crystal modulation member 14 does not rotate the polarization direction of incident light when no electric field is applied, and rotates the polarization direction of incident light when an electric field is applied. In this case, the pair of polarizing plates 15 and 16 are arranged such that the polarization directions intersect, more specifically, such that the polarization directions are orthogonal. That is, the video light ML or the external light OL emitted from the polarizing plate 16 after passing through the transmissive liquid crystal panel 22 has a first polarization P1 whose polarization direction is in the vertical first direction (see FIG. 5). The transmissive liquid crystal panel 22 can switch ON and OFF in units of pixels PX according to a drive signal from the drive circuit 81 (see FIG. 2) and can partially transmit incident light at an arbitrary gradation between ON and OFF. For this reason, the liquid crystal modulation member 14 includes not only a liquid crystal layer 31, a common electrode 32, a pixel electrode 33, and a black matrix 35, but also a scanning line, a signal line, a switching element, etc., which are not shown in the figure.

[0026] Note that the transmissive liquid crystal panel 22 or the liquid crystal modulation member 14 may be one that rotates the polarization direction of incident light when no electric field is applied and does not rotate the polarization direction of incident light when an electric field is applied. In this case, the pair of polarizing plates 15 and 16 are arranged such that the polarization directions are parallel to each other.

[0027] The switching 1 / 2 wavelength plate 23 is disposed on the opposite side of the light guide plate 11 facing the transmissive liquid crystal panel 22. The switching 1 / 2 wavelength plate 23 is a device that performs a switching-type operation according to a drive signal from a drive circuit 81 (see FIG. 2), and switches and passes the polarization direction of incident light between a first direction and a second direction that intersect each other according to the alignment direction of the liquid crystal. The switching 1 / 2 wavelength plate 23 includes a liquid crystal layer 17a sandwiched between a pair of base materials 17b and 17c via a transparent electrode layer (not shown). The liquid crystal layer 17a is, for example, an in-plane switching (IPS) type liquid crystal or the like, which does not rotate the polarization direction of incident light when no electric field is applied, and rotates the polarization direction of incident light when an electric field is applied. The switching 1 / 2 wavelength plate 23 can switch ON and OFF over the entire surface rather than in pixel units. When the switching 1 / 2 wavelength plate 23 is in the OFF state, the switching 1 / 2 wavelength plate 23 functions as a transparent flat plate as a whole, and transmits the video light ML (that is, the first polarization P1 whose polarization direction is the vertical first direction, i.e., the ±Y direction) while maintaining its polarization direction (see the first region AR1 in FIG. 5). On the other hand, when the switching 1 / 2 wavelength plate 23 is in the ON state, the switching 1 / 2 wavelength plate 23 functions as a 1 / 2 wavelength plate having a main axis in the middle of the X direction and the Y direction as a whole, rotates the polarization direction of the external light OL (that is, the first polarization P1 whose polarization direction is the vertical first direction) by 90°, and emits it as the second polarization P2 whose polarization direction is the horizontal second direction (see the second region AR2 in FIG. 5).

[0028] The polarizing lens 50 disposed on the front face side of the switching 1 / 2 wavelength plate 23 includes a liquid crystal layer 18a sandwiched between a pair of base materials 18b and 18c with a transparent electrode layer (not shown) interposed therebetween. As described above, the liquid crystal layer 18a includes a number of circular ring-shaped portions RA (see FIG. 2) having different refractive index states around the optical axis AX along the XY plane. With respect to the first polarization P1 whose polarization direction is the vertical first direction parallel to the paper surface, that is, the ±Y direction, that is, with respect to the video light ML, the refractive index gradually decreases from the central ring-shaped portion RA through which the optical axis AX passes to the outer edge ring-shaped portion RA, and functions as a lens having positive power. The position of the focal point of the polarizing lens 50 is the position of the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22. Also, with respect to the second polarization P2 whose polarization direction is the horizontal second direction perpendicular to the paper surface, that is, the ±X direction, that is, with respect to the external light OL, the refractive index of each ring-shaped portion RA is uniform, and it functions as a parallel flat plate. As a result, the polarizing lens 50 has a refractive power for forming the first polarization P1 in the first direction as a virtual image, and allows the second polarization P2 in the second direction to pass through.

[0029] Hereinafter, with reference to FIG. 5, the state of light in the first display optical system 103a will be described. In FIG. 5, the first region AR1 shows the case where the first display optical system 103a is in the video observation period and the transmissive liquid crystal panel 22 is in the display state, and the second region AR2 shows the case where the first display optical system 103a is in the external light observation period and the transmissive liquid crystal panel 22 is in the non-display state. In the transmissive liquid crystal panel 22, the display state is a state in which the illumination light IL passing through the scattering region 12b of the scattering member 12 is incident to form the video light ML, and the non-display state is a state in which the external light OL passing through the transmissive region 12a of the scattering member 12 is transmitted.

[0030] In the first stage of the image observation period, among the light emitting elements 10r, 10g, and 10b of the light source 10, for example, the R light emitting element 10r emits light, and illumination light ILr which is red light is supplied to the light guide member 21. The illumination light ILr guides light within the light guide plate 11 and becomes a scattered state in the scattering region 12b of the scattering member 12. The illumination light ILr illuminates the liquid crystal modulation member 14 as the second polarization P2 which is horizontal polarization through the first polarizing plate 15 of the transmissive liquid crystal panel 22. That is, each colorless pixel PX constituting the transmissive liquid crystal panel 22 is illuminated. The video light QL that has passed through the liquid crystal modulation member 14 is the one whose polarization plane of the illumination light ILr is rotated according to the drive signal, and only the first polarization P1 which is vertical polarization is emitted as the video light ML(R) through the second polarizing plate 16. The video light ML(R) emitted from each pixel PX of the transmissive liquid crystal panel 22 is incident on the switching 1 / 2 wavelength plate 23. At this time, the switching 1 / 2 wavelength plate 23 is switched to the OFF state and functions like a transparent flat plate, and transmits the video light ML(R) of the first polarization P1 while maintaining its polarization direction. The video light ML(R) of the first polarization P1 that has passed through the switching 1 / 2 wavelength plate 23 forms a virtual image through the polarization lens 50 that functions as a convex lens with respect to the first polarization P1.

[0031] In the second stage of the image observation period, the G light emitting element 10g of the light source 10 emits light instead of the R light emitting element 10r, illumination light ILg which is green light is supplied to the light guide member 21, and is emitted laterally from the light guide member 21. The video light QL that passes through each pixel PX constituting the transmissive liquid crystal panel 22 or the liquid crystal modulation member 14 illuminated by the illumination light ILg is the one whose polarization plane of the illumination light ILg is rotated according to the drive signal, and each pixel PX of the transmissive liquid crystal panel 22 emits the video light ML(G) which is the first polarization P1. The switching 1 / 2 wavelength plate 23 is maintained in the OFF state, and the video light ML(G) of the first polarization P1 that has passed through the switching 1 / 2 wavelength plate 23 forms a virtual image through the polarization lens 50 that functions as a convex lens with respect to the first polarization P1.

[0032] In the third stage of the image observation period, the B light-emitting element 10b of the light source 10 emits light instead of the G light-emitting element 10g, and illumination light ILb, which is blue light, is supplied to the light guide member 21 and is emitted laterally from the light guide member 21. The image light QL passing through each pixel PX constituting the transmissive liquid crystal panel 22 or the liquid crystal modulation member 14 illuminated by the illumination light ILb is obtained by rotating the polarization plane of the illumination light ILb according to the drive signal, and each pixel PX of the transmissive liquid crystal panel 22 emits the image light ML(B) which is the first polarization P1. The switching 1 / 2 wavelength plate 23 is maintained in the OFF state, and the image light ML(B) of the first polarization P1 passing through the switching 1 / 2 wavelength plate 23 forms a virtual image through the polarization lens 50 that functions as a convex lens with respect to the first polarization P1.

[0033] During the above image observation period, that is, when the transmissive liquid crystal panel 22 is in the display state, the three-color image lights ML(R), ML(G), and ML(B) are sequentially displayed, and the switching 1 / 2 wavelength plate 23 makes the first polarization P1, which is the image light ML from the transmissive liquid crystal panel 22, incident on the polarization lens 50, and the wearer US recognizes a color image.

[0034] On the other hand, during the external light observation period, the light source 10 is set to a non-light-emitting state, that is, a turned-off state, and the supply of the illumination light IL to the light guide member 21 is stopped. The external light OL enters the transmission region 12a of the scattering member 12 and passes through the light guide plate 11. As a result, the external light OL travels straight so as to intersect the light guide member 21 and enters the transmissive liquid crystal panel 22. At this time, each pixel PX of the transmissive liquid crystal panel 22 operates in, for example, a normally-off state and is set to a maximum transmission state by a drive signal. Among the external light OL incident on the pixel PX of the transmissive liquid crystal panel 22, the second polarization P2 travels straight through the transmissive liquid crystal panel 22, that is, the pixel PX, and is converted into the first polarization P1 and enters the switching 1 / 2 wavelength plate 23. At this time, the switching 1 / 2 wavelength plate 23 is switched to the ON state and functions as a 1 / 2 wavelength plate, rotates the polarization direction of the external light OL that is the first polarization P1 by 90°, and emits it as the second polarization P2. That is, when the transmissive liquid crystal panel 22 is in a non-display state, the switching 1 / 2 wavelength plate 23 causes the external light OL that has passed through the transmissive liquid crystal panel 22 to enter the polarization lens 50 as the second polarization P2. The external light OL of the second polarization P2 that has passed through the switching 1 / 2 wavelength plate 23 enters the eye EY without being subjected to an imaging action by the composite display member 20 or the polarization lens 50 through the polarization lens 50 that functions as a parallel plate with respect to the second polarization P2.

[0035] FIG. 6 is a timing chart for explaining the display operation by the first virtual image display device 100A. The horizontal axis represents time. In order from the top, there are shown the blinking signal SS1 of the R light-emitting element 10r, the R drive signal SM1 for red display applied to the liquid crystal modulation member 14, the blinking signal SS2 of the G light-emitting element 10g, the G drive signal SM2 for green display applied to the liquid crystal modulation member 14, the blinking signal SS3 of the B light-emitting element 10b, the B drive signal SM3 for blue display applied to the liquid crystal modulation member 14, and the on / off signal SW of the switching 1 / 2 wavelength plate (1 / 2λ) 23. The operation of the first virtual image display device 100A has, in each frame, a first sub-frame Z1 that is a sub-frame for video observation and a second sub-frame Z2 that is a sub-frame for external light observation.

[0036] In the red display section Δ1, which is the first stage of the first sub-frame Z1 for video observation, the drive circuit 81 turns on the R light-emitting element 10r, outputs an R drive signal SM1 for red display to each pixel PX of the transmissive liquid crystal panel 22, and sets the switching 1 / 2 wavelength plate 23 to the OFF state. As a result, red video light ML(R) is incident on the eye EY, and the polarizing lens 50 enables the observation of a virtual image corresponding to the red pattern formed on the transmissive liquid crystal panel 22. In the green display section Δ2, which is the second stage of the first sub-frame Z1, the drive circuit 81 turns on the G light-emitting element 10g, outputs a G drive signal SM2 for green display to each pixel PX of the transmissive liquid crystal panel 22, and maintains the OFF state of the switching 1 / 2 wavelength plate 23. As a result, green video light ML(G) is incident on the eye EY, and the polarizing lens 50 enables the observation of a virtual image corresponding to the green pattern formed on the transmissive liquid crystal panel 22. In the blue display section Δ3, which is the third stage of the first sub-frame Z1, the drive circuit 81 turns on the B light-emitting element 10b, outputs a B drive signal SM3 for blue display to each pixel PX of the transmissive liquid crystal panel 22, and maintains the OFF state of the switching 1 / 2 wavelength plate 23. As a result, blue video light ML(B) is incident on the eye EY, and the polarizing lens 50 enables the observation of a virtual image corresponding to the blue pattern formed on the transmissive liquid crystal panel 22.

[0037] During the above first sub-frame Z1, that is, the video observation period, the three-color video lights ML(R), ML(G), and ML(B) are sequentially displayed by the transmissive liquid crystal panel 22 in the display state or the transmissive state, and the wearer US recognizes a color image.

[0038] In the second sub-frame Z2 for external light observation, the drive circuit 81 turns off the light source 10, outputs a drive signal for maximum transmission, for example, to each pixel PX of the transmissive liquid crystal panel 22, and sets the switching 1 / 2 wavelength plate 23 to the ON state. At this time, the transmissive liquid crystal panel 22 is in the non-display state and the transmissive state. As a result, external light OL that travels straight through the transmissive liquid crystal panel 22 and the polarizing lens 50 is incident on the eye EY, enabling the observation of the external image.

[0039] The structure of the first embodiment described above is an example. For example, the transmissive liquid crystal panel 22 does not necessarily need to operate in the normally-off state and may operate in the normally-on state. When operating in the normally-on state, the drive signals SM1, SM2, and SM3 shown in FIG. 6 are inverted with respect to the tuning, that is, the magnitudes of the applied voltages are inverted. The transmissive liquid crystal panel 22 is not limited to an IPS-type liquid crystal element and may be other types of liquid crystal display elements such as TN-type liquid crystal elements.

[0040] The switching 1 / 2 wavelength plate 23 may be configured to rotate the polarization direction of the video light ML by 90° and emit it as the second polarization P2, while transmitting the external light OL as the first polarization P1 while maintaining its polarization direction. In this case, the polarizing lens 50 has a refractive power to form the video light ML of the second polarization P2 as a virtual image and transmits the external light OL of the first polarization P1 as a parallel plate as it is. Note that the second polarization P2 that undergoes the imaging action by such a polarizing lens 50 can be called the first polarization, and the first polarization P1 that does not undergo the imaging action by this polarizing lens 50 can be called the second polarization.

[0041] The first sub-frame Z1 and the second sub-frame Z2 shown in FIG. 6 are merely examples, and the time widths and time ratios of the sub-frames Z1 and Z2 can be adjusted according to the external environment by, for example, the control device 80, and can also be adjusted by the wearer US via the user terminal 90.

[0042] In the first sub-frame Z1, it is not necessary to set the pixel PX of the transmissive liquid crystal panel 22 to the maximum transmission state, and by adjusting the transmittance of the pixel PX, the transmission intensity of the external light OL can be adjusted like a dimming sunglass. At this time, the transmittance can be adjusted not for the entire surface of the transmissive liquid crystal panel 22 but for a local area.

[0043] The virtual image display devices 100A and 100B of the first embodiment described above include, in order from the outside world, a light guide member 21 that propagates illumination light IL from a light source 10, a scattering member 12 provided on the light guide member 21 and having a transmission region 12a and a scattering region 12b, a transmissive liquid crystal panel 22 that becomes a display state and a non-display state, a switching 1 / 2 wavelength plate 23 that switches the polarization directions of incident light to a first direction and a second direction that intersect each other, and a polarization lens 50 that has a refractive power to form an image of the polarization in the first direction as a virtual image and allows the polarization in the second direction to pass through. The transmission region 12a is disposed at a position facing either a pixel PX or a sub-pixel of the transmissive liquid crystal panel 22. The switching 1 / 2 wavelength plate 23 causes video light ML to enter the polarization lens 50 as the first polarization P1 in the first direction in the case of the display state, and causes external light OL to enter the polarization lens 50 as the second polarization P2 in the second direction in the case of the non-display state.

[0044] In the above virtual image display device, when the transmissive liquid crystal panel 22 is in the display state, the switching 1 / 2 wavelength plate 23 causes video light ML from the transmissive liquid crystal panel 22 to enter the polarization lens 50 as the first polarization P1 in the first direction, and when the transmissive liquid crystal panel 22 is in the non-display state, causes external light OL that has passed through the transmissive liquid crystal panel 22 to enter the polarization lens 50 as the second polarization P2 in the second direction. Therefore, it becomes possible to switch and observe the video light ML and the external light OL in parallel. That is, the transmissive liquid crystal panel 22 can be used for video observation and external light observation by using the scattering member 12, and a decrease in the see-through transmittance can be suppressed while ensuring the brightness of the display.

[0045] In the virtual image display devices 100A and 100B of the first embodiment, the light source 10 generates illumination light of red, green, and blue by switching, the transmissive liquid crystal panel 22 has colorless pixels PX, modulates according to the color of the illumination light generated by the light source 10 by the pixels PX, and makes the pixels PX in a transmissive state when the light source 10 is not emitting light. In this case, during the first sub-frame Z1, which is a sub-frame for video observation, there are display sections Δ1, Δ2, and Δ3 for each color that display video lights ML(R), ML(G), and ML(B) of red, green, and blue.

[0046] 〔Second Embodiment〕 Next, the virtual image display device and the like according to the second embodiment will be described. Note that the virtual image display device according to the second embodiment is a partially modified version of the virtual image display device according to the first embodiment, and descriptions of parts common to the virtual image display device according to the first embodiment will be omitted.

[0047] In the first display optical system 103a or the first virtual image display device 100A shown in FIG. 7, the scattering member 12 is disposed on the surface of the light guide plate 11 facing the transmissive liquid crystal panel 22, that is, on the flat surface 11b on the back side of the light guide plate 11. Thereby, the scattered light can be concentrated in a relatively extremely small region. The illumination light IL, which is the scattered light that has passed through the scattering region 12b, is emitted by the nanostructure NS in the direction of the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22.

[0048] Next, with reference to FIG. 8, the state of light in the first display optical system 103a will be described. In FIG. 8, the first region BR1 shows the case where the first display optical system 103a is in the video observation period and the transmissive liquid crystal panel 22 is in the display state, and the second region BR2 shows the case where the first display optical system 103a is in the external light observation period and the transmissive liquid crystal panel 22 is in the non-display state.

[0049] During the video observation period, that is, when the transmissive liquid crystal panel 22 is in the display state, the three-color video lights ML(R), ML(G), and ML(B) are sequentially displayed, and the switching 1 / 2 wavelength plate 23 causes the first polarization P1, which is the video light ML from the transmissive liquid crystal panel 22, to enter the polarization lens 50, and the wearer US recognizes the color image.

[0050] On the other hand, during the external light observation period, the light source 10 is set to a non-emitting state, that is, the off state, and the supply of the illumination light IL to the light guide member 21 is stopped. The external light OL passes through the light guide plate 11 and then through the transmission region 12a of the scattering member 12. As a result, the external light OL travels straight so as to intersect the light guide member 21 and is incident on the transmissive liquid crystal panel 22. At this time, each pixel PX of the transmissive liquid crystal panel 22 is, for example, in the maximum transmission state in the normally-on state. Among the external light OL incident on the pixel PX of the transmissive liquid crystal panel 22, the second polarization P2 travels straight through the transmissive liquid crystal panel 22, that is, the pixel PX, and is converted into the first polarization P1 and then is incident on the switching 1 / 2 wavelength plate 23. At this time, the switching 1 / 2 wavelength plate 23 in the ON state rotates the polarization direction of the external light OL of the first polarization P1 by 90° and emits it as the second polarization P2. The external light OL of the second polarization P2 that has passed through the switching 1 / 2 wavelength plate 23 passes through the polarizing lens 50 that functions as a parallel plate with respect to the second polarization P2 and is incident on the eye EY without undergoing an imaging effect by the composite display member 20 or the polarizing lens 50.

[0051] 〔Third Embodiment〕 Hereinafter, the virtual image display device and the like of the third embodiment will be described. 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 the description of the parts common to the virtual image display device of the first embodiment will be omitted.

[0052] In the first display optical system 103a or the first virtual image display device 100A shown in FIG. 9, the transmissive liquid crystal panel 22 includes sub-pixels PXs, specifically, three types of sub-pixels PXs(R), PXs(G), and PXs(B). Although not shown, these sub-pixels PXs(R), PXs(G), and PXs(B) are arranged in a stripe shape or a Bayer shape to form the pixel PX.

[0053] In the sub-pixels PXs(R) for red display, a red color filter 41r is disposed near the first polarizing plate 15. In the sub-pixels PXs(G) for green display, a green color filter 41g is disposed near the first polarizing plate 15. In the sub-pixels PXs(B) for blue display, a blue color filter 41b is disposed near the first polarizing plate 15.

[0054] Referring to FIG. 10, the state of light in the first display optical system 103a will be described. In FIG. 10, the first region CR1 shows the case where the first display optical system 103a is in the video observation period and the transmissive liquid crystal panel 22 is in the display state, and the second region CR2 shows the case where the first display optical system 103a is in the external light observation period and the transmissive liquid crystal panel 22 is in the non-display state.

[0055] During the video observation period, by causing all the light-emitting elements 10r, 10g, 10b constituting the light source 10 to emit light, white illumination lights ILr, ILg, ILb are supplied to the light guide member 21. The illumination lights ILr, ILg, ILb are scattered in the scattering region 12b of the scattering member 12 and emitted from the light guide member 21. Among the illumination lights ILr, ILg, ILb, the second polarization P2 illuminates the sub-pixels PXs(R), PXs(G), PXs(B) constituting each pixel PX through the first polarizing plate 15 of the transmissive liquid crystal panel 22. As a result, the modulated ML(R), ML(G), ML(B) of the first polarization P1 are emitted in parallel from the transmissive liquid crystal panel 22. The video lights ML(R), ML(G), ML(B) emitted from the respective sub-pixels PXs(R), PXs(G), PXs(B) of the transmissive liquid crystal panel 22 enter the OFF-state switching 1 / 2 wavelength plate 23. The switching 1 / 2 wavelength plate 23 transmits the video lights ML(R), ML(G), ML(B) of the first polarization P1 while maintaining their polarization directions. The video lights ML(R), ML(G), ML(B) of the first polarization P1 that have passed through the switching 1 / 2 wavelength plate 23 form virtual images through the polarization lens 50 that functions as a convex lens with respect to the first polarization P1.

[0056] On one hand, during the external light observation period, the light source 10 is set to a non-emitting state, that is, the lighting is turned off, and the supply of the illumination light IL to the light guide member 21 is stopped. The external light OL enters the transmission region 12a of the scattering member 12 and passes through the light guide plate 11. As a result, the external light OL travels straight so as to intersect the light guide member 21 and enters the transmissive liquid crystal panel 22. At this time, the sub-pixels PXs(R), PXs(G), and PXs(B) constituting each pixel PX of the transmissive liquid crystal panel 22 are, for example, in the maximum transmission state, and the second polarization P2 of the external light OL travels straight through the transmissive liquid crystal panel 22, that is, the sub-pixels PXs(R), PXs(G), and PXs(B), and is converted into the first polarization P1 and enters the switching 1 / 2 wavelength plate 23. The switching 1 / 2 wavelength plate 23 in the ON state rotates the polarization direction of the external light OL of the first polarization P1 by 90° and emits it as the second polarization P2. The external light OL of the second polarization P2 that has passed through the switching 1 / 2 wavelength plate 23 enters the eye EY without being subjected to an imaging effect by the composite display member 20 or the polarization lens 50 via the polarization lens 50 that functions as a parallel plate with respect to the second polarization P2.

[0057] FIG. 11 is a timing chart for explaining the display operation by the first virtual image display device 100A, and corresponds to the timing chart shown in FIG. 6 of the first embodiment. In this case, instead of sequentially displaying the three-color video lights ML(R), ML(G), and ML(B) in a time division manner, the three-color video lights ML(R), ML(G), and ML(B) are displayed simultaneously in parallel. When the first virtual image display device 100A is in the external light observation period and the transmissive liquid crystal panel 22 is in a non-display state, the external light OL evenly passes through the sub-pixels PXs(R), PXs(G), and PXs(B) of the transmissive liquid crystal panel 22, so that an observation of an external image without coloring becomes possible.

[0058] Also in this embodiment, the switching 1 / 2 wavelength plate 23 may be configured to rotate the polarization direction of the video light ML by 90° and emit it as the second polarization P2, while transmitting the external light OL as the first polarization P1 while maintaining its polarization direction. Further, the time widths and time ratios of the sub-frames Z1 and Z2 can be adjusted according to the external environment by, for example, the control device 80.

[0059] In the second sub-frame Z2 for external light observation, it is not necessary to set each sub-pixel PXs(R), PXs(G), PXs(B) constituting the transmissive liquid crystal panel 22 to the maximum transmission state, and the transmittance of each sub-pixel PXs(R), PXs(G), PXs(B) can be individually adjusted.

[0060] Further, the scattering member 12 of the present embodiment may be disposed on the surface of the light guide plate 11 facing the transmissive liquid crystal panel 22, that is, on the flat surface 11b on the back side of the light guide plate 11, like the scattering member 12 of the second embodiment.

[0061] In the virtual image display devices 100A and 100B of the third embodiment, the light source 10 generates white illumination lights ILr, ILg, ILb, the transmissive liquid crystal panel 22 has red, green, and blue sub-pixels PXs(R), PXs(G), PXs(B), modulation is performed by the sub-pixels PXs(R), PXs(G), PXs(B) of each color in accordance with the light emission of the light source 10, and each sub-pixel PXs(R), PXs(G), PXs(B) of each color is in a transmissive state when the light source 10 is not emitting light. In this case, in the first sub-frame Z1 which is a sub-frame for video observation, red, green, and blue video lights ML can be simultaneously displayed.

[0062] 〔Fourth Embodiment〕 Hereinafter, the virtual image display device and the like of the fourth embodiment will be described. The virtual image display device of the fourth embodiment is a partial modification of the virtual image display devices of the first and third embodiments, and the description of the parts common to the virtual image display devices of the first embodiment and the like will be omitted.

[0063] In the first display optical system 103a or the first virtual image display device 100A shown in FIGS. 12 and 13, the transmissive liquid crystal panel 22 includes sub-pixels PXs, specifically, four types of sub-pixels PXs(R), PXs(G), PXs(B), PXs(T). The three types of sub-pixels PXs(R), PXs(G), PXs(B) all have color filters 41r, 41g, 41b and are for video light ML. The remaining one type of sub-pixel PXs(T) does not have a color filter and is for external light OL.

[0064] Referring to FIG. 14, the arrangement of sub-pixels PXs in pixel PX will be described. In FIG. 14, the first region DR1 shows an example of the arrangement of sub-pixels PXs, and the second region DR2 shows another example of the arrangement of sub-pixels PXs. The four types of sub-pixels PXs (R), PXs (G), PXs (B), PXs (T) are in an equal stripe arrangement, but can also be arranged in a Bayer pattern.

[0065] During the video observation period shown in FIG. 12, by causing all the light-emitting elements 10r, 10g, 10b constituting the light source 10 to emit light, white illumination lights ILr, ILg, ILb are supplied to the light guide member 21. The illumination lights ILr, ILg, ILb are scattered in the scattering region 12b of the scattering member 12 and emitted from the light guide member 21. Among the illumination lights ILr, ILg, ILb, the second polarization P2 illuminates the sub-pixels PXs (R), PXs (G), PXs (B), PXs (T) constituting each pixel PX through the first polarizing plate 15 of the transmissive liquid crystal panel 22. As a result, the modulated ML (R), ML (G), ML (B) of the first polarization P1 are emitted in parallel from the transmissive liquid crystal panel 22. However, the sub-pixel PXs (T) is in an OFF state and does not transmit the illumination light. The video lights ML (R), ML (G), ML (B) emitted from each sub-pixel PXs (R), PXs (G), PXs (B) of the transmissive liquid crystal panel 22 enter the OFF-state switching 1 / 2 wavelength plate 23. The switching 1 / 2 wavelength plate 23 transmits the video lights ML (R), ML (G), ML (B) of the first polarization P1 while maintaining their polarization directions. The video lights ML (R), ML (G), ML (B) of the first polarization P1 that have passed through the switching 1 / 2 wavelength plate 23 form virtual images through the polarization lens 50 that functions as a convex lens with respect to the first polarization P1.

[0066] On the other hand, during the external light observation period shown in FIG. 13, the light source 10 is set to a non-light-emitting state, that is, the light-off state, and the supply of the illumination light IL to the light guide member 21 is stopped. The external light OL enters the transmission region 12a of the scattering member 12 and passes through the light guide plate 11. As a result, the external light OL travels straight so as to cross the light guide member 21 and enters the transmissive liquid crystal panel 22. At this time, the sub-pixels PXs(R), PXs(G), PXs(B), and PXs(T) constituting each pixel PX of the transmissive liquid crystal panel 22 are driven to, for example, the maximum transmission state. Among the external light OL, the second polarization P2 travels straight through the transmissive liquid crystal panel 22, that is, the sub-pixels PXs(R), PXs(G), PXs(B), and PXs(T), and is converted into the first polarization P1 and enters the switching 1 / 2 wavelength plate 23. The switching 1 / 2 wavelength plate 23 in the ON state rotates the polarization direction of the external light OL of the first polarization P1 by 90° and emits it as the second polarization P2. The external light OL of the second polarization P2 that has passed through the switching 1 / 2 wavelength plate 23 enters the eye EY without being subjected to an imaging action by the composite display member 20 or the polarization lens 50 via the polarization lens 50 that functions as a parallel plate with respect to the second polarization P2.

[0067] FIG. 15 is a timing chart for explaining the display operation by the first virtual image display device 100A. FIG. 15 is obtained by adding a W drive signal SM4 for the sub-pixel PXs(T) to the drive signals similar to those in FIG. 11.

[0068] The first virtual image display device 100A displays the three-color video lights ML(R), ML(G), and ML(B) simultaneously in parallel. In the present embodiment, in the second sub-frame Z2 for external light observation, the drive circuit 81 outputs a W drive signal SM4 not only to the sub-pixels PXs(R), PXs(G), and PXs(B) but also to the sub-pixel PXs(T) for the external light OL in addition to the output of the drive signals SM1 to SM3. When the first virtual image display device 100A is in the external light observation period and the transmissive liquid crystal panel 22 is in the non-display state, the external light OL evenly passes through the sub-pixels PXs(R), PXs(G), and PXs(B) of the transmissive liquid crystal panel 22, so that it is possible to observe an external image without coloring. Further, since the external light OL also passes through the sub-pixel PXs(T) of the transmissive liquid crystal panel 22, the see-through image can be made brighter.

[0069] In the virtual image display devices 100A and 100B according to the fourth embodiment, the light source 10 generates white illumination lights ILr, ILg, and ILb, and the transmissive liquid crystal panel 22 has red, green, and blue sub-pixels PXs(R), PXs(G), and PXs(B). In accordance with the light emission of the light source 10, modulation is performed by the sub-pixels PXs(R), PXs(G), and PXs(B) of each color, and the colorless sub-pixel PXs(T) is in a transmissive state when the light source 10 is not emitting light. In this case, in the first sub-frame Z1 which is a sub-frame for video observation, red, green, and blue video lights ML(R), ML(G), and ML(B) can be simultaneously displayed. In the second sub-frame Z2 which is a sub-frame for external light observation, by operating at least the colorless sub-pixel PXs(T), it becomes possible to observe in a time-division manner between a color video and a see-through image.

[0070] 〔Modification examples and others〕 Although the present invention has been described in accordance with the above embodiments, the present invention is not limited to the above embodiments, and can be implemented in various aspects without departing from the gist thereof. For example, the following modifications are possible.

[0071] In the scattering member 12, the scattering region 12b entirely surrounds the periphery of the transmission region 12a, but it is not necessary to entirely surround it. Also, the arrangement etc. of the transmission region 12a and the scattering region 12b can be appropriately changed.

[0072] The scattering member 12 does not have to be formed by processing the surface of the light guide plate 11. The scattering member 12 may be, for example, a sheet-like member having a transmission region 12a and a scattering region 12b attached to the surface of the light guide plate 11.

[0073] The scattering member 12 may be provided on both surfaces 11a and 11b of the light guide plate 11.

[0074] The liquid crystal lens as the polarizing lens 50 is not limited to one including a ring-shaped zone portion RA. As the polarizing lens 50, various structures having a lens action for a specific polarization can be adopted.

[0075] In the above description, it was assumed that the HMD 200 is used while being worn on the head. However, the virtual image display devices 100A and 100B can also be used as a hand-held display that peeks in like binoculars without being worn on the head. That is, in the present invention, the head-mounted display includes a hand-held display.

[0076] The virtual image display device in a specific embodiment includes, in order from the outside world, a light guide member that propagates illumination light from a light source, a scattering member provided on the light guide member and having a transmission region and a scattering region, a transmissive liquid crystal panel that becomes a display state and a non-display state, a switching 1 / 2 wavelength plate that switches the polarization direction of incident light to a first direction and a second direction that cross each other, and a polarization lens that has a refractive power to form an image of the polarization in the first direction as a virtual image and allows the polarization in the second direction to pass through. The transmission region is disposed at a position facing either the pixel or the sub-pixel of the transmissive liquid crystal panel. The switching 1 / 2 wavelength plate makes video light incident on the polarization lens as polarization in the first direction in the display state, and makes external light incident on the polarization lens as polarization in the second direction in the non-display state.

[0077] In the above virtual image display device, the switching 1 / 2 wavelength plate makes video light from the transmissive liquid crystal panel incident on the polarization lens as polarization in the first direction when the transmissive liquid crystal panel is in the display state, and makes external light passing through the transmissive liquid crystal panel incident on the polarization lens as polarization in the second direction when the transmissive liquid crystal panel is in the non-display state. Therefore, it becomes possible to switch and observe the video light and the external light in parallel. That is, the transmissive liquid crystal panel can be used for video observation and external light observation by using the scattering member, and it is possible to suppress a decrease in the see-through transmittance while ensuring the brightness of the display.

[0078] In the virtual image display device in a specific embodiment, the transmission region transmits external light, and the scattering region scatters illumination light.

[0079] In the virtual image display device in a specific embodiment, the scattering region is arranged around the transmission region. In this case, a large amount of illumination light can be made to enter the transmissive liquid crystal panel.

[0080] In the virtual image display device in a specific embodiment, the scattering region has a nanostructure that controls the scattering direction and scattering angle of the illumination light. In this case, the illumination light can be efficiently made to enter the transmissive liquid crystal panel.

[0081] In the virtual image display device in a specific embodiment, the scattering member is arranged on the surface of the light guide plate provided in the light guide member on the side opposite to the transmissive liquid crystal panel. In this case, the emission angle of the scattered light can be loosened, making it easier to control the scattering angle while facilitating the production of the scattering member.

[0082] In the virtual image display device in a specific embodiment, the scattering member is arranged on the surface of the light guide plate provided in the light guide member facing the transmissive liquid crystal panel. In this case, the scattered light can be concentrated in a relatively minimal region.

[0083] In the virtual image display device in a specific embodiment, the light source generates illumination light by switching between red, green, and blue, and the transmissive liquid crystal panel has colorless pixels and modulates according to the color of the illumination light generated by the light source by the pixels, and the pixels are in a transmissive state when the light source is not emitting light. In this case, during the sub-frame for video observation, there are display intervals for each color that display red, green, and blue video light.

[0084] In the virtual image display device in a specific embodiment, the light source generates white illumination light, and the transmissive liquid crystal panel has red, green, and blue sub-pixels and modulates by the respective sub-pixels according to the emission of the light source, and the respective sub-pixels are in a transmissive state when the light source is not emitting light. In this case, in the sub-frame for video observation, red, green, and blue video light can be displayed simultaneously.

[0085] In a virtual image display device according to a specific embodiment, a light source generates white illumination light, and a transmissive liquid crystal panel has red, green, blue, and colorless sub-pixels. In accordance with the light emission of the light source, modulation is performed by the sub-pixels of each color, and the colorless sub-pixels are in a transmissive state when the light source is not emitting light. In this case, in a sub-frame for observing an image, red, green, and blue image lights can be displayed simultaneously, and in a sub-frame for observing external light, by operating at least the colorless sub-pixels, it becomes possible to observe a color image and a see-through image in a time-division manner.

[0086] In a virtual image display device according to a specific embodiment, a transmissive liquid crystal panel has each color sub-pixel in a transmissive state when the light source is not emitting light. In this case, in a sub-frame for observing external light, each color sub-pixel can be utilized, and the see-through image can be brightened.

[0087] In a virtual image display device according to a specific embodiment, colorless sub-pixels are arranged in a stripe shape or a Bayer shape together with sub-pixels of each color to form pixels.

[0088] In a virtual image display device according to a specific embodiment, a scattering member makes illumination light that has passed through a scattering region enter in a display state to form image light, and makes external light that has passed through a transmission region pass through in a non-display state.

[0089] In a virtual image display device according to a specific embodiment, a transmissive liquid crystal panel has a liquid crystal modulation member and a pair of polarizing plates sandwiching the liquid crystal modulation member. The pair of polarizing plates are set in a direction where the polarization directions intersect, or in a direction where the polarization directions are parallel, according to the characteristics and driving method of the liquid crystal modulation member.

[0090] In a virtual image display device according to a specific embodiment, it further includes a drive circuit that operates the light source, the transmissive liquid crystal panel, and the switching 1 / 2 wavelength plate in synchronization.

Explanation of Reference Numerals

[0091] 10…Light source, 10b…B light-emitting element, 10g…G light-emitting element, 10r…R light-emitting element, 11…Light guide plate, 11a, 11b…Planes, 12…Scattering member, 12a…Transmission region, 12b…Scattering region, 20…Composite display member, 21…Light guide member, 22…Transmissive liquid crystal panel, 23…Switching 1 / 2 wavelength plate, 31…Liquid crystal layer, 32…Common electrode, 33…Pixel electrode, 35…Black matrix, 41r, 41g, 41b…Color filter, 50…Polarizing lens, 80…Control device, 81…Driver circuit, 90…User terminal, 100A, 100B…Virtual image display device, 100C…Template, 102…Driver device, 102a, 102b…Display driving unit, 103a, 103b…Display optical system, 104…Shade, 106…Support device, 200…Head-mounted display device, 201…Binocular display device, AX…Optical axis, EY…Eye, IL, ILr, ILg, ILb…Illumination light, ML, QL…Video light, NS…Nanostructure, OL…Ambient light, OP…Opening, PX…Pixel, PXs…Sub-pixel, US…Wearer, Z1, Z2…Sub-frame

Claims

1. In the order from the outside, a light guide member that propagates illumination light from a light source, a scattering member provided on the light guide member and having a transmission region and a scattering region, a transmissive liquid crystal panel that becomes a display state and a non-display state, a switching 1 / 2 wavelength plate that switches the polarization directions of incident light to a first direction and a second direction that intersect each other, a polarizing lens that has a refractive power to form an image of the polarization in the first direction as a virtual image and passes the polarization in the second direction, The transmission region is disposed at a position facing either a pixel or a sub-pixel of the transmissive liquid crystal panel, The switching 1 / 2 wavelength plate makes video light incident on the polarizing lens as polarization in the first direction in the display state, and makes external light incident on the polarizing lens as polarization in the second direction in the non-display state, A virtual image display device.

2. The transmission region transmits the external light, and the scattering region scatters the illumination light, The virtual image display device according to Claim 1.

3. The scattering region is disposed around the transmission region, The virtual image display device according to Claim 1.

4. The scattering region has a nanostructure that controls the scattering direction and scattering angle of the illumination light, The virtual image display device according to Claim 1.

5. The scattering member is disposed on a surface of a light guide plate provided on the light guide member, on the side opposite to the transmissive liquid crystal panel, The virtual image display device according to Claim 1.

6. The scattering member is disposed on a surface of a light guide plate provided on the light guide member, facing the transmissive liquid crystal panel, The virtual image display device according to Claim 1.

7. The light source generates illumination light by switching among red, green, and blue, The transmissive liquid crystal panel has colorless pixels, modulates according to the color of the illumination light generated by the light source by the pixels, and makes the pixels in a transmissive state when the light source is not emitting light, The virtual image display device according to Claim 1.

8. The light source generates white illumination light, The transmissive liquid crystal panel has red, green, and blue sub-pixels, modulates according to the emission of the light source by the sub-pixels of each color, and makes the sub-pixels of each color in a transmissive state when the light source is not emitting light, The virtual image display device according to Claim 1.

9. The light source generates white illumination light, The transmissive liquid crystal panel has red, green, blue, and colorless sub-pixels, modulates according to the emission of the light source by the sub-pixels of each color, and makes the colorless sub-pixels in a transmissive state when the light source is not emitting light, The virtual image display device according to claim 1.

10. When the light source is not emitting light, the transmissive liquid crystal panel makes each of the sub-pixels of each color in a transmissive state. The virtual image display device according to claim 9.

11. The colorless sub-pixels are arranged in a stripe shape or a Bayer shape together with the sub-pixels of each color to form the pixels. The virtual image display device according to claim 8.

12. The scattering member allows the illumination light passing through the scattering region in the display state to be incident to form the video light, and allows the external light passing through the transmission region in the non-display state to pass through. The virtual image display device according to claim 1.

13. The transmissive liquid crystal panel has a liquid crystal modulation member and a pair of polarizing plates sandwiching the liquid crystal modulation member. The virtual image display device according to claim 1.

14. It further includes a drive circuit that synchronizes and operates the light source, the transmissive liquid crystal panel, and the switching 1 / 2 wavelength plate. The virtual image display device according to claim 1.

Images