Virtual image display device

Abstract

The invention provides a virtual image display device which improves perspective transmittance in an image display area. The virtual image display device includes, in 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 is in a display state and a non-display state; a switching 1 / 2 wavelength plate that switches the polarization direction of the incident light to a first direction and a second direction that intersect each other; and a polarizing lens having a refractive power for imaging the polarized light in the first direction as a virtual image and allowing the polarized light in the second direction to pass therethrough, the transmission region being disposed at a position facing either the pixel or the sub-pixel of the transmission-type liquid crystal panel. The switching 1 / 2 wavelength plate causes the image light to be incident on the polarizing lens as polarized light in the first direction in a display state, and causes the external light to be incident on the polarizing lens as polarized light in the second direction in a non-display state.

Description

Technical Field

[0001] The present invention relates to a virtual image display device capable of observing a virtual image, and particularly to a see-through virtual image display device capable of visually confirming an external image. Background Art

[0002] As a see-through virtual image display device capable of visually confirming an external image, the following device 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 on an end portion from a light source. 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 transmissive area that transmits ambient light (Patent Document 1). This virtual image display device is configured such that ambient light reaches an observer from the light transmissive 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 structure, see-through display in which image light and ambient light are overlapped is achieved.

[0003] Patent Document 1: WO 2016 / 056298

[0004] In the above device, processing such as dot formation and coating of a scattering material is performed in the light emitting area of the light guide plate, and ambient light passing through the image display area of the liquid crystal panel passes through the processed light emitting area, so that the see-through transmittance near the center of the field of view corresponding to the image display area is reduced. In order to achieve see-through display with a high see-through transmittance near the center of the field of view, an optical system with a high see-through transmittance is additionally required, resulting in an increase in size. Summary of the Invention

[0005] A virtual image display device according to an aspect of the present invention includes, in order from the outside: a light guide member that propagates illumination light from a light source; a scattering member that is provided on the light guide member and has a transmissive area and a scattering area; a transmissive liquid crystal panel that assumes a display state and a non-display state; a switchable 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 for forming a virtual image of the polarized light in the first direction and allows the polarized light in the second direction to pass through. The transmissive area is disposed at a position facing either a pixel or a sub-pixel of the transmissive liquid crystal panel. The switchable 1 / 2 wavelength plate causes image light to be incident on the polarization lens as the polarized light in the first direction in the display state, and causes external light to be incident on the polarization lens as the polarized light in the second direction in the non-display state. Brief Description of the Drawings

[0006] Figure 1It is an external perspective view showing the wearing state of the virtual image display device of the first embodiment.

[0007] Figure 2 It is a conceptual perspective view showing the optical structure of the virtual image display device.

[0008] Figure 3 It is an enlarged side cross-sectional view showing the optical structure of the virtual image display device.

[0009] Figure 4 It is a conceptual top view showing the scattering member.

[0010] Figure 5 It is a view showing the state of light passing through the display optical system.

[0011] Figure 6 It is a view showing the operation of the virtual image display device.

[0012] Figure 7 It is an enlarged side cross-sectional view showing the virtual image display device of the second embodiment.

[0013] Figure 8 It is a view showing the state of light passing through the display optical system.

[0014] Figure 9 It is an enlarged side cross-sectional view showing the virtual image display device of the third embodiment.

[0015] Figure 10 It is a view showing the state of light passing through the display optical system.

[0016] Figure 11 It is a view showing the operation of the virtual image display device.

[0017] Figure 12 It is an enlarged side cross-sectional view showing the virtual image display device of the fourth embodiment.

[0018] Figure 13 It is an enlarged side cross-sectional view showing the virtual image display device of the fourth embodiment.

[0019] Figure 14 It is a view showing the pixel structure.

[0020] Figure 15 It is a view showing the operation of the virtual image display device.

[0021] Reference Numeral Explanation

[0022] 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: Switchable 1 / 2 wavelength plate; 31: Liquid crystal layer; 32: Common electrode; 33: Pixel electrode; 35: Black matrix; 41r, 41g, 41b: Color filters; 50: Polarizing lens; 80: Control device; 81: Driving circuit; 90: User terminal; 100A, 100B: Virtual image display devices; 100C: Temple; 102: Driving device; 102a, 102b: Display driving units; 103a, 103b: Display optical systems; 104: Light-shielding member; 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: Image light; NS: Nanostructure; OL: External light; OP: Opening; PX: Pixel; PXs: Sub-pixel; US: Wearer; Z1, Z2: Sub-frames. Detailed implementation mode

[0023] First implementation mode

[0024] Hereinafter, with reference to Figures 1 to 6 , the virtual image display device according to the first implementation mode of the present invention will be described.

[0025] Figure 1 is a perspective view showing 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, which enables an observer or wearer US wearing it to recognize an image as a virtual image. In Figure 1 etc., X, Y, and Z are orthogonal coordinate systems. The +X direction corresponds to the horizontal direction in which the two eyes EY of the observer or wearer US wearing the HMD 200 are arranged. The +Y direction is equivalent to the upward direction orthogonal to the horizontal direction in which the two eyes EY of the wearer US are arranged. The +Z direction is equivalent to the front direction or the front face direction of the wearer US. The ±Y direction is parallel to the vertical axis or the vertical direction.

[0026] The HMD 200 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 temple arms 100C that support the virtual image display devices 100A and 100B, and a user terminal 90 that serves as an information terminal. The first virtual image display device 100A is composed of a first display driving unit 102a arranged at the upper part, a first display optical system 103a covering in front of the eyes, and a light transmissive cover 104a covering 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 arranged at the upper part, a second display optical system 103b covering in front of the eyes, and a light transmissive cover 104b covering the second display optical system 103b on the outside or front side. The HMD 200 formed by 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 temple arms 100C are wearing parts or support devices 106 worn on the head of the wearer US, and support the upper end sides of the pair of display optical systems 103a and 103b and the upper end sides of the pair of light transmissive covers 104a and 104b via the display driving units 102a and 102b that are integrated in appearance. The component formed by combining the pair of display driving units 102a and 102b is called a driving device 102. The component formed by combining the pair of light transmissive covers 104a and 104b is called a light shielding member 104.

[0027] Figure 2 It is a perspective view showing the structure of the first display optical system 103a. The first display optical system 103a includes: a light source 10 that generates light of three colors as illumination light in a time-division manner; a plate-shaped composite display component 20 that forms a two-dimensional image and emits image light ML; and a polarization lens 50 that functions as a lens for the image light ML. The light source 10 is also Figure 1 a part of the first display driving unit 102a shown, and is arranged near the upper side of the upper edge of the light guide component 21 in a manner that supplies illumination light to the light guide component 21 (to be described later) in the composite display component 20 from the upper edge. The light source 10 and the composite display component 20 are driven by the driving circuit 81 of the control device 80 of the first display driving unit 102a to operate, and at the same time, the observation of the virtual image based on the image light ML and the perspective observation of the outside world are realized. That is, the driving circuit 81 synchronizes the operations of the light source 10, the transmissive liquid crystal panel 22, and the switch 1 / 2 wavelength plate 23. The composite display component 20 and the polarization lens 50 are arranged separately 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. In addition, the distance between the composite display component 20 and the polarization lens 50 is, for example, about 3 mm to 25 mm.

[0028] 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 for example, can be light-emitting diodes such as organic light-emitting diodes (OLEDs) or 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 assembled individually. 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. Between the light source 10 and the light guide member 21 of the composite display member 20, an optical combiner / divider including a beam splitter can be assembled to assist in the diffusion of illumination light.

[0029] The composite display member 20 is a plate-shaped member extending along the XY plane perpendicular to the optical axis AX, and sequentially includes a light guide member 21, a transmissive liquid crystal panel 22, and a switch 1 / 2 wavelength plate 23 from the outside. The composite display member 20 is a plate-shaped member formed by laminating the light guide member 21, the transmissive liquid crystal panel 22, and the switch 1 / 2 wavelength plate 23, 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 switch 1 / 2 wavelength plate 23 are fixed to each other in a state where they are arranged at a predetermined interval in the vicinity. In addition, the transmissive liquid crystal panel 22 includes a plurality of pixels PX arranged in a matrix along the XY plane (refer to Figure 3 ).

[0030] The polarization lens 50 is disposed on the front side (i.e., the -Z side) of the composite display member 20 and covers the front of the eye. More specifically, the polarization lens 50 is disposed on the opposite side of the transmissive liquid crystal panel 22 so as to face the switch 1 / 2 wavelength plate 23 in the composite display member 20. The polarization lens 50 is a plate-shaped member extending along the XY plane. The function of the polarization lens 50 varies depending on the polarization direction of the incident light. The polarization lens 50 functions as a lens for the image light ML emitted from the composite display member 20. That is, the polarization lens 50 collectively images the plurality of pixels constituting the transmissive liquid crystal panel 22, and the image formed on the transmissive liquid crystal panel 22 can be observed as a virtual image. On the other hand, the polarization lens 50 functions as a parallel plate with respect to the external light OL passing through the composite display member 20. Specifically, the polarization lens 50 is a liquid crystal lens and includes a plurality of circular annulus portions RA having different refractive index states. A set of annulus portions RA are symmetrically and concentrically arranged around the optical axis AX. The annulus portion RA at the periphery far from the optical axis AX in a set of annulus portions RA has a narrower radial width centered on the optical axis AX than the central annulus portion RA through which the optical axis AX passes. That is, the radial width of the annulus portion RA becomes narrower as it is closer to the periphery.

[0031] The second display optical system 103b is optically identical to the first display optical system 103a, or the first display optical system 103a is reversed left and right. Detailed description thereof is omitted.

[0032] Refer to Figure 3 , the light source 10 generates three-color illumination lights ILr, ILg, and ILb as the illumination light IL 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 to be white light when they overlap.

[0033] The light guide member 21 is formed by attaching a scattering member 12 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 illumination lights ILr, ILg, and ILb incident from the light source 10 downward. In addition, the light guide plate 11 allows external light OL to pass through. The light guide plate 11 has a thickness of about 0.5 mm, for example. The light guide plate 11 is formed of a light-transmissive plastic, glass, or the like.

[0034] The light guide plate 11 is formed of a light-transmissive flat plate and has a pair of flat surfaces 11a and 11b. The scattering member 12 is provided on the flat surface 11a on the front side or the outside of the light guide plate 11. That is, the scattering member 12 is disposed on the flat surface 11a on the side opposite to the transmissive liquid crystal panel 22 in the light guide plate 11. By providing the scattering member 12 on the flat surface 11a on the outside of the light guide plate 11, the emission angle of the scattered light can be moderated, and it is easy to manufacture the scattering member 12 and control the scattering angle.

[0035] Figure 4 is a conceptual plan view for explaining the scattering member 12. In Figure 4 it shows the transmissive liquid crystal panel 22 (refer to Figure 3) The scattering member 12 corresponding to the pixel PX. The scattering member 12 is provided in the light guide member 21 including the light guide plate 11. The scattering member 12 has a transmissive region 12a and a scattering region 12b disposed around the transmissive region 12a. In the entire light guide member 21, a plurality of repeating partitions 12c each having the transmissive region 12a and the scattering region 12b as a set are two-dimensionally arranged as the scattering member 12. In the present embodiment, the scattering member 12 represents one repeating partition 12c or an aggregate of a plurality of repeating partitions 12c. The repeating partition 12c has a quadrangular contour in a plan view, but its shape can be appropriately changed. In addition, a gap may exist between adjacent repeating partitions 12c. The repeating partition 12c may be arranged in units of pixels PX or in units of sub-pixels. In each repeating partition 12c, the arrangement, area, etc. of the transmissive region 12a and the scattering region 12b may be the same or different.

[0036] The transmissive region 12a allows the external light OL to pass through. The scattering region 12b scatters the illumination light IL (ILr, ILg, ILb) and emits it outside the light guide plate 11. Thus, the scattering member 12 creates a transparent state that allows the external light OL to pass through and pass by using the transmissive region 12a, and creates a scattering state that emits the illumination light IL outside the light guide plate 11 by using the scattering region 12b. That is, the scattering member 12 can simultaneously form a scattering state and a transparent state, and can separately emit the illumination light IL and the external light OL. The display switching between the image light ML formed by the illumination light IL and the external light OL is performed by the ON (open) / OFF (closed) of the switch 1 / 2 wavelength plate 23.

[0037] The transmissive region 12a is disposed at a position opposed to the pixel PX of the transmissive liquid crystal panel 22. That is, the transmissive region 12a corresponds to the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22. In the present embodiment, the transmissive region 12a is the plane 11a of the light guide plate 11 and has a smooth surface. The transmissive region 12a has a contour such as a circle, an ellipse, a quadrangle, a polygon, etc. in a plan view.

[0038] The scattering region 12b is partially disposed on the light guide plate 11 in units of pixels PX or sub-pixels in the repeating partition 12c. The scattering region 12b is disposed so as to surround the transmission region 12a. Specifically, the scattering region 12b is disposed around the transmission region 12a and 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 outline of the repeating partition 12c and the transmission region 12a. In the illustrated example, the scattering region 12b has a quadrilateral outer shape in plan view, and the central portion has a shape with a circular cutout. Further, if the outline of the transmission region 12a is a quadrilateral, the scattering region 12b can be made to approximate the shape of the black matrix 35. The repeating partition 12c may also include a partition that does not have the transmission region 12a, that is, a partition in which the entire repeating partition 12c is the scattering region 12b.

[0039] The scattering member 12 makes the area of the transmission region 12a smaller than the size of the opening OP in the case of the priority image light ML. Further, the scattering member 12 increases the area of the transmission region 12a, for example, to be approximately the same size as the opening OP, in the case of giving priority to the external light OL.

[0040] The scattering region 12b has a nano-structure NS. The scattered light, that is, the illumination light IL, reflected by the scattering region 12b is emitted in the direction of the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22 through the nano-structure NS. The scattering state in the scattering region 12b may be Lambert scattering or may be directional scattering. The nano-structure NS can control the scattering direction and scattering angle of the illumination light IL so that a large amount of light can be diffracted to a specified portion. By converging the illumination light IL as a directional scattered light to the opening OP of the transmissive liquid crystal panel 22, the light utilization efficiency can be improved.

[0041] The scattering member 12 is formed of glass, plastic, etc., similarly to the light guide plate 11 as a base material. The scattering member 12 has the same refractive index as the light guide plate 11. The nano-structure NS is formed by nanoimprint lithography, photolithography, or the like.

[0042] Return Figure 3, the transmissive liquid crystal panel 22 is disposed on the face side, i.e., the -Z side, opposite to the light guide plate 11. The transmissive liquid crystal panel 22 includes a liquid crystal modulation component 14 and a pair of polarizing plates 15 and 16 sandwiching the liquid crystal modulation component 14. In this case, the transmissive liquid crystal panel 22 or the liquid crystal modulation component 14 is a modulation element composed of, for example, in-plane switching (IPS) type liquid crystal, etc., and operates in units of pixels PX. The pixel PX does not have a color filter and is colorless. In the transmissive liquid crystal panel 22, the size of the region forming the pixel PX is about 1 to 2 inches, and the number of pixels is about 2K to 4K. The liquid crystal modulation component 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 are in a crossed direction, more specifically, in an orthogonal direction. That is, the image light ML or the external light OL emitted from the polarizing plate 16 through the transmissive liquid crystal panel 22 becomes the first polarized light P1 in the first direction with the polarization direction being longitudinal (refer to Figure 5 ). The transmissive liquid crystal panel 22 can switch ON (open) and OFF (closed) in units of pixels PX according to a drive signal from the drive circuit 81 (refer to Figure 2 ), and can partially pass incident light at an arbitrary gray level between ON and OFF. Therefore, the liquid crystal modulation component 14 not only has a liquid crystal layer 31, a common electrode 32, a pixel electrode 33, and a black matrix 35, but also has scan lines, signal lines, switching elements, etc. which are not shown.

[0043] In addition, the transmissive liquid crystal panel 22 or the liquid crystal modulation component 14 may rotate the polarization direction of incident light when no electric field is applied, and 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.

[0044] The switch 1 / 2 wavelength plate 23 is disposed on the opposite side of the light guide plate 11 opposite to the transmissive liquid crystal panel 22. The switch 1 / 2 wavelength plate 23 is based on a drive signal from the drive circuit 81 (refer to Figure 2A device that performs a switching operation based on a drive signal of (), which switches the polarization direction of incident light to the first direction and the second direction that cross each other according to the alignment direction of the liquid crystal and allows it to pass through. The switching half-wave plate 23 includes a liquid crystal layer 17a sandwiched between a pair of substrates 17b and 17c with an unillustrated transparent electrode layer therebetween. 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 half-wave plate 23 can switch ON and OFF over the entire surface instead of in units of pixels. When the switching half-wave plate 23 is in the OFF state, the entire switching half-wave plate 23 functions as a transparent flat plate, and allows the image light ML (i.e., the first polarized light P1 with a polarization direction in the longitudinal first direction of ±Y direction) to pass through while maintaining its polarization direction (refer to Figure 5 the first region AR1). On the other hand, when the switching half-wave plate 23 is in the ON state, the entire switching half-wave plate 23 functions as a half-wave plate having a main axis in the middle of the X direction and the Y direction, rotates the polarization direction of the external light OL (i.e., the first polarized light P1 with a polarization direction in the longitudinal first direction) by 90°, and emits it as the second polarized light P2 with a polarization direction in the transverse second direction (refer to Figure 5 the second region AR2).

[0045] The polarization lens 50 disposed on the face side of the switching half-wave plate 23 includes a liquid crystal layer 18a sandwiched between a pair of substrates 18b and 18c with an unillustrated transparent electrode layer therebetween. As described above, the liquid crystal layer 18a includes a plurality of circular annulus portions RA having different refractive index states around the optical axis AX along the XY plane (refer to Figure 2 ). Regarding the first polarized light P1 with a polarization direction in the longitudinal first direction parallel to the paper surface, i.e., ±Y direction, which is the image light ML, the refractive index of the liquid crystal layer 18a gradually decreases from the central annulus portion RA passing through the optical axis AX to the outer annulus portion RA, and functions as a lens with positive refractive power. The position of the focal point of the polarization lens 50 is the position of the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22. In addition, regarding the second polarized light P2 with a polarization direction in the transverse second direction perpendicular to the paper surface, i.e., ±X direction, which is the external light OL, the refractive indices of the respective annulus portions RA of the liquid crystal layer 18a are the same, and it functions as a parallel flat plate. As a result, the polarization lens 50 has a refractive power that forms a virtual image of the first polarized light P1 in the first direction and allows the second polarized light P2 in the second direction to pass through.

[0046] Hereinafter, with reference to Figure 5 the state of light in the first display optical system 103a will be described. In Figure 5In the figure, the first area AR1 shows a case where the first display optical system 103a is in an image observation period and the transmissive liquid crystal panel 22 is in a display state, and the second area AR2 shows a case where the first display optical system 103a is in an external light observation period and the transmissive liquid crystal panel 22 is in a 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 area 12b of the scattering member 12 is incident to form the image light ML, and the non-display state is a state in which the external light OL passing through the transmissive area 12a of the scattering member 12 is transmitted.

[0047] In the first stage during the image observation period, for example, the R light-emitting element 10r among the light-emitting elements 10r, 10g, and 10b of the light source 10 emits light, and supplies the illumination light ILr as red light to the light guide member 21. The illumination light ILr is guided in the light guide plate 11 and becomes a scattered state in the scattering area 12b of the scattering member 12. The illumination light ILr illuminates the liquid crystal modulation member 14 as the transverse polarized light, that is, the second polarized light P2, via 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 image 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 the image light ML(R) as the first polarized light P1 only is emitted through the second polarizing plate 16. The image light ML(R) emitted from each pixel PX of the transmissive liquid crystal panel 22 is incident on the switch 1 / 2 wavelength plate 23. At this time, the switch 1 / 2 wavelength plate 23 is switched to the OFF state and functions as a transparent flat plate, and the image light ML(R) of the first polarized light P1 is transmitted while maintaining its polarization direction. The image light ML(R) of the first polarized light P1 that has passed through the switch 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 polarized light P1.

[0048] In the second stage during 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, supplies the illumination light ILg as green light to the light guide member 21, and emits it laterally from the light guide member 21. The image light QL passing through each pixel PX of the transmissive liquid crystal panel 22 or the liquid crystal modulation member 14 illuminated by the illumination light ILg is obtained by rotating the polarization plane of the illumination light ILg according to the drive signal, and the image light ML(G) as the first polarized light P1 is emitted from each pixel PX of the transmissive liquid crystal panel 22. The switch 1 / 2 wavelength plate 23 maintains the OFF state, and the image light ML(G) of the first polarized light P1 that has passed through the switch 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 polarized light P1.

[0049] In the third stage during image observation, the B light-emitting element 10b of the light source 10 emits light instead of the G light-emitting element 10g, and the illumination light ILb as blue light is supplied to the light guide member 21 and emitted laterally from the light guide member 21. The image light QL of 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 the image light ML(B) as the first polarized light P1 is emitted from each pixel PX of the transmissive liquid crystal panel 22. The switch 1 / 2 wavelength plate 23 maintains the OFF state, and the image light ML(B) of the first polarized light P1 that has passed through the switch 1 / 2 wavelength plate 23 forms a virtual image via the polarization lens 50 that functions as a convex lens with respect to the first polarized light P1.

[0050] During the above image observation period, that is, when the transmissive liquid crystal panel 22 is in the display state, the image lights ML(R), ML(G), and ML(B) of three colors are sequentially displayed, and the switch 1 / 2 wavelength plate 23 makes the image light ML from the transmissive liquid crystal panel 22, that is, the first polarized light P1, incident on the polarization lens 50, and the wearer US recognizes the color image.

[0051] On the other hand, during the external light observation period, the light source 10 is set to the non-light-emitting state, that is, the extinguished state, and the supply of the illumination light IL to the light guide member 21 is stopped. The external light OL is incident on the transmissive region 12a of the scattering member 12 and passes through the light guide plate 11. Thus, the external light OL travels straight in a manner intersecting 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 operates in a normally OFF manner, for example, and becomes the maximum transmission state according to the drive signal. The second polarized light P2 in the external light OL incident on the pixel PX of the transmissive liquid crystal panel 22 travels straight in the transmissive liquid crystal panel 22, that is, the pixel PX, and is converted into the first polarized light P1 and is incident on the switch 1 / 2 wavelength plate 23. At this time, the switch 1 / 2 wavelength plate 23 is switched to the ON state and functions as a 1 / 2 wavelength plate, rotating the polarization direction of the external light OL as the first polarized light P1 by 90° and emitting it as the second polarized light P2. That is, when the transmissive liquid crystal panel 22 is in the non-display state, the switch 1 / 2 wavelength plate 23 makes the external light OL that has passed through the transmissive liquid crystal panel 22 incident on the polarization lens 50 as the second polarized light P2. The external light OL of the second polarized light P2 that has passed through the switch 1 / 2 wavelength plate 23 is incident on the eye EY via the polarization lens 50 that functions as a parallel plate with respect to the second polarized light P2 without being affected by the imaging action of the composite display member 20 and the polarization lens 50.

[0052] Figure 6This is a timing chart showing the display operation of the first virtual image display device 100A. The horizontal axis represents time, and from top to bottom, it successively shows the blinking signal SS1 of the R light-emitting element 10r, the R drive signal SM1 for red display supplied to the liquid crystal modulation component 14, the blinking signal SS2 of the G light-emitting element 10g, the G drive signal SM2 for green display supplied to the liquid crystal modulation component 14, the blinking signal SS3 of the B light-emitting element 10b, the B drive signal SM3 for blue display supplied to the liquid crystal modulation component 14, and the ON / OFF signal SW of the switch 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 as a sub-frame for image viewing and a second sub-frame Z2 as a sub-frame for external light viewing.

[0053] In the first stage red display interval Δ1 of the first sub-frame Z1 for image viewing, the drive circuit 81 turns on the R light-emitting element 10r, outputs the R drive signal SM1 for red display to each pixel PX of the transmissive liquid crystal panel 22, and makes the switch 1 / 2 wavelength plate 23 in the OFF state. As a result, the red image light ML(R) is incident on the eye EY, and through the polarization lens 50, a virtual image corresponding to the red pattern formed on the transmissive liquid crystal panel 22 can be observed. In the second stage green display interval Δ2 of the first sub-frame Z1, the drive circuit 81 turns on the G light-emitting element 10g, outputs the G drive signal SM2 for green display to each pixel PX of the transmissive liquid crystal panel 22, and maintains the switch 1 / 2 wavelength plate 23 in the OFF state. As a result, the green image light ML(G) is incident on the eye EY, and through the polarization lens 50, a virtual image corresponding to the green pattern formed on the transmissive liquid crystal panel 22 can be observed. In the third stage blue display interval Δ3 of the first sub-frame Z1, the drive circuit 81 turns on the B light-emitting element 10b, outputs the B drive signal SM3 for blue display to each pixel PX of the transmissive liquid crystal panel 22, and maintains the switch 1 / 2 wavelength plate 23 in the OFF state. As a result, the blue image light ML(B) is incident on the eye EY, and through the polarization lens 50, a virtual image corresponding to the blue pattern formed on the transmissive liquid crystal panel 22 can be observed.

[0054] During the above first sub-frame Z1, i.e., the image viewing period, the transmissive liquid crystal panel 22 in the display state or the transmissive state successively displays the three-color image lights ML(R), ML(G), and ML(B), and the wearer US recognizes the color image.

[0055] The drive circuit 81 turns off the light source 10 in the second sub-frame Z2 for external light observation, outputs, for example, a drive signal for maximum transmission to each pixel PX of the transmissive liquid crystal panel 22, and turns on the switch 1 / 2 wavelength plate 23. At this time, the transmissive liquid crystal panel 22 becomes a non-display state and a transmissive state. As a result, the external light OL traveling straight through the transmissive liquid crystal panel 22 and the polarization lens 50 enters the eye EY, and the outside image can be observed.

[0056] The configuration of the first embodiment described above is an example. For example, the transmissive liquid crystal panel 22 does not need to operate in a normally-closed manner and may operate in a normally-open manner. In the case of operating in a normally-open manner, Figure 6 the drive signals SM1, SM2, and SM3 shown are signals obtained by inverting the gray scale, that is, signals obtained by inverting the magnitude of the applied voltage. 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 a TN-type liquid crystal element.

[0057] The switch 1 / 2 wavelength plate 23 may also rotate the polarization direction of the image light ML by 90° and emit it as the second polarized light P2, and transmit the external light OL as the first polarized light P1 while maintaining its polarization direction. In this case, the polarization lens 50 has a refractive power for imaging the image light ML of the second polarized light P2 as a virtual image and directly transmits the external light OL of the first polarized light P1 as a parallel plate. In addition, the second polarized light P2 that is imaged by passing through such a polarization lens 50 can be referred to as the first polarized light, and the first polarized light P1 that is not imaged by passing through this polarization lens 50 can be referred to as the second polarized light.

[0058] Figure 6 The first sub-frame Z1 and the second sub-frame Z2 shown 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 the control device 80, for example, and can also be adjusted by the wearer US via the user terminal 90.

[0059] In the first sub-frame Z1, it is not necessary to make the pixel PX of the transmissive liquid crystal panel 22 in a maximum transmission state. By adjusting the transmittance of the pixel PX, the transmission intensity of the external light OL can be adjusted like an adjustable sunglasses. At this time, the transmittance may be adjusted not for the entire surface of the transmissive liquid crystal panel 22 but for a partial area.

[0060] The virtual image display devices 100A and 100B of the first embodiment described above sequentially include, 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 region 12a and a scattering region 12b; a transmissive liquid crystal panel 22 that assumes a display state and a non-display state; a switch 1 / 2 wavelength plate 23 that switches the polarization direction of incident light to a first direction and a second direction that cross each other; and a polarization lens 50 that has a refractive power for imaging the polarized light in the first direction as a virtual image and allows the polarized light in the second direction to pass through. The transmission region 12a is disposed at a position facing either the pixel PX or the sub-pixel of the transmissive liquid crystal panel 22. In the display state, the switch 1 / 2 wavelength plate 23 causes image light ML to enter the polarization lens 50 as polarized light in the first direction, and in the non-display state, causes external light OL to enter the polarization lens 50 as polarized light in the second direction.

[0061] In the above virtual image display device, when the transmissive liquid crystal panel 22 is in the display state, the switch 1 / 2 wavelength plate 23 causes image light ML from the transmissive liquid crystal panel 22 to enter the polarization lens 50 as first polarized light 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 second polarized light P2 in the second direction. Therefore, it is possible to switch between the image light ML and the external light OL and perform parallel observation. That is, the transmissive liquid crystal panel 22 can be used for both image observation and external light observation by the scattering member 12, and it is possible to suppress a decrease in the perspective transmittance while ensuring the brightness of the display.

[0062] In the virtual image display devices 100A and 100B of the first embodiment, the light source 10 alternately generates illumination light of red, green, and blue. The transmissive liquid crystal panel 22 has colorless pixels PX, and modulates the pixels PX corresponding to the colors of the illumination light generated by the light source 10, and makes the pixels PX in a transmissive state when the light source 10 is not emitting light. In this case, in the first sub-frame Z1 that is a sub-frame for image observation, there are display intervals Δ1, Δ2, and Δ3 for displaying image lights ML(R), ML(G), and ML(B) of red, green, and blue colors, respectively.

[0063] Second Embodiment

[0064] Hereinafter, the virtual image display device and the like of the second embodiment will be described. In addition, the virtual image display device of the second embodiment is obtained by partially modifying the virtual image display device of the first embodiment, and the description of the parts that are the same as those of the virtual image display device of the first embodiment will be omitted.

[0065] In Figure 7In the first display optical system 103a or the first virtual image display device 100A shown, the scattering member 12 is disposed on the plane 11b on the back side of the light guide plate 11, which is the surface of the light guide plate 11 facing the transmissive liquid crystal panel 22. Thereby, the scattered light can be concentrated in a relatively extremely small area. The scattered light, i.e., the illumination light IL, that has passed through the scattering region 12b is emitted in the direction of the opening OP (pixel electrode 33) of the transmissive liquid crystal panel 22 through the nano-structure NS.

[0066] Hereinafter, with reference to Figure 8 the state of light in the first display optical system 103a will be described. In Figure 8 , the first region BR1 represents the case where the first display optical system 103a is in the image observation period and the transmissive liquid crystal panel 22 is in the display state, and the second region BR2 represents 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.

[0067] During the 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 switch 1 / 2 wavelength plate 23 makes the image light ML from the transmissive liquid crystal panel 22, that is, the first polarized light P1, incident on the polarization lens 50, and the wearer US recognizes the color image.

[0068] On the other hand, during the external light observation period, the light source 10 is made in the non-luminous state, that is, the extinguished 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 passes through the transmissive region 12a of the scattering member 12. Thereby, the external light OL travels straight in a manner intersecting 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 becomes the maximum transmission state, for example, in the normally open mode, and the second polarized light P2 in the external light OL incident on the pixel PX of the transmissive liquid crystal panel 22 travels straight in the transmissive liquid crystal panel 22 and is converted into the first polarized light P1 and is incident on the switch 1 / 2 wavelength plate 23. At this time, the ON-state switch 1 / 2 wavelength plate 23 rotates the polarization direction of the external light OL of the first polarized light P1 by 90° and emits it as the second polarized light P2. The external light OL of the second polarized light P2 that has passed through the switch 1 / 2 wavelength plate 23 is incident on the eye EY via the polarization lens 50 that functions as a parallel plate with respect to the second polarized light P2 without being affected by the imaging action of the composite display member 20 and the polarization lens 50.

[0069] Third Embodiment

[0070] Hereinafter, the virtual image display device and the like of the third embodiment will be described. In addition, the virtual image display device of the third embodiment is obtained by partially changing the virtual image display device of the first embodiment, and the description of the same parts as the virtual image display device of the first embodiment will be omitted.

[0071] In Figure 9 the first display optical system 103a or the first virtual image display device 100A shown, the transmissive liquid crystal panel 22 includes sub-pixels PXs, specifically including 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 pattern or a Bayer pattern to form a pixel PX.

[0072] In the red display sub-pixel PXs(R), a red color filter 41r is disposed near the first polarizing plate 15. In the green display sub-pixel PXs(G), a green color filter 41g is disposed near the first polarizing plate 15. In the blue display sub-pixel PXs(B), a blue color filter 41b is disposed near the first polarizing plate 15.

[0073] Referring to Figure 10 , the state of light in the first display optical system 103a will be described. In Figure 10 , the first region CR1 shows the case where the first display optical system 103a is in the image 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.

[0074] During the image observation, by causing all the light-emitting elements 10r, 10g, and 10b constituting the light source 10 to emit light, white illumination lights ILr, ILg, and ILb are supplied to the light guide member 21. The illumination lights ILr, ILg, and ILb are scattered in the scattering region 12b of the scattering member 12 and emitted from the light guide member 21. The second polarized light P2 in the illumination lights ILr, ILg, and ILb illuminates the sub-pixels PXs(R), PXs(G), and PXs(B) constituting each pixel PX via the first polarizing plate 15 of the transmissive liquid crystal panel 22. As a result, ML(R), ML(G), and ML(B) of the modulated first polarized light P1 are emitted in parallel from the transmissive liquid crystal panel 22. The image lights ML(R), ML(G), and ML(B) emitted from the sub-pixels PXs(R), PXs(G), and PXs(B) of the transmissive liquid crystal panel 22 are incident on the OFF-state switch 1 / 2 wavelength plate 23. The switch 1 / 2 wavelength plate 23 allows the image lights ML(R), ML(G), and ML(B) of the first polarized light P1 to pass through while maintaining their polarization directions. The image lights ML(R), ML(G), and ML(B) of the first polarized light P1 that have passed through the switch 1 / 2 wavelength plate 23 form a virtual image via the polarization lens 50 that functions as a convex lens with respect to the first polarized light P1.

[0075] On the other hand, during the external light observation, the light source 10 is made non-luminous, i.e., in the extinguished state, and the supply of the illumination light IL to the light guide member 21 is stopped. The external light OL is incident on 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 in a manner intersecting the light guide member 21 and is incident on 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 polarized light P2 in the external light OL travels straight through the transmissive liquid crystal panel 22, i.e., the sub-pixels PXs(R), PXs(G), and PXs(B), and is converted into the first polarized light P1 and incident on the switch 1 / 2 wavelength plate 23. The ON-state switch 1 / 2 wavelength plate 23 rotates the polarization direction of the external light OL of the first polarized light P1 by 90° and emits it as the second polarized light P2. The external light OL of the second polarized light P2 that has passed through the switch 1 / 2 wavelength plate 23 is incident on the eye EY via the polarization lens 50 that functions as a parallel plate with respect to the second polarized light P2 without being affected by the imaging action of the composite display member 20 and the polarization lens 50.

[0076] Figure 11 is a timing chart for explaining the display operation of the first virtual image display device 100A, and is the same as that of the first embodiment Figure 6The corresponding timing chart is shown. In this case, instead of sequentially displaying the three-color image lights ML(R), ML(G), and ML(B) in a time-division manner, the three-color image lights ML(R), ML(G), and ML(B) are simultaneously displayed side by side. 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 passes through the sub-pixels PXs(R), PXs(G), and PXs(B) of the transmissive liquid crystal panel 22 with good balance, so that an uncolored external image can be observed.

[0077] In the present embodiment, the switchable 1 / 2 wavelength plate 23 can also rotate the polarization direction of the image light ML by 90° and emit it as the second polarized light P2, and allow the external light OL to pass through as the first polarized light P1 while maintaining its polarization direction. In addition, the time widths and time ratios of the sub-frames Z1 and Z2 can be adjusted by the control device 80 according to the external environment, for example.

[0078] In the second sub-frame Z2 for external light observation, it is not necessary to make each of the sub-pixels PXs(R), PXs(G), and PXs(B) constituting the transmissive liquid crystal panel 22 in the maximum transmission state, and the transmittances of the sub-pixels PXs(R), PXs(G), and PXs(B) can be adjusted individually.

[0079] In addition, the scattering member 12 of the present embodiment can also be arranged on the plane 11b on the back side of the light guide plate 11, which is the surface of the light guide plate 11 facing the transmissive liquid crystal panel 22, like the scattering member 12 of the second embodiment.

[0080] In the virtual image display devices 100A and 100B of the third 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). Corresponding to the light emission of the light source 10, modulation is performed using the sub-pixels PXs(R), PXs(G), and PXs(B) of each color, and when the light source 10 does not emit light, the sub-pixels PXs(R), PXs(G), and PXs(B) of each color are made in a transmissive state. In this case, in the first sub-frame Z1 as the image observation sub-frame, the red, green, and blue image lights ML can be simultaneously displayed.

[0081] Fourth Embodiment

[0082] Hereinafter, the virtual image display device and the like of the fourth embodiment will be described. In addition, the virtual image display device of the fourth embodiment is obtained by partially changing the virtual image display devices of the first and third embodiments, and the description of the parts identical to the virtual image display devices of the first embodiment and the like is omitted.

[0083] InFigure 12 and Figure 13 In the first display optical system 103a or the first virtual image display device 100A shown in Figure 13 , the transmissive liquid crystal panel 22 includes sub-pixels PXs, specifically including four types of sub-pixels PXs(R), PXs(G), PXs(B), and PXs(T). Three types of sub-pixels PXs(R), PXs(G), and PXs(B) all have color filters 41r, 41g, and 41b for image light ML. The remaining one type of sub-pixel PXs(T) does not have a color filter and is for external light OL.

[0084] Refer to Figure 14 , and the arrangement of sub-pixels PXs in pixel PX will be described. In Figure 14 , the first region DR1 represents an example of the arrangement of sub-pixels PXs, and the second region DR2 represents another example of the arrangement of sub-pixels PXs. Four types of sub-pixels PXs(R), PXs(G), PXs(B), and PXs(T) are arranged in an equal stripe pattern, but they can also be arranged in a Bayer pattern.

[0085] During Figure 12 the image observation period shown in Figure 12 , by causing all the light-emitting elements 10r, 10g, and 10b of the light source 10 to emit light, white illumination light ILr, ILg, and ILb is supplied to the light guide member 21. The illumination light ILr, ILg, and ILb is scattered in the scattering region 12b of the scattering member 12 and emitted from the light guide member 21. The second polarized light P2 in the illumination light ILr, ILg, and ILb illuminates the sub-pixels PXs(R), PXs(G), PXs(B), and PXs(T) that make up each pixel PX via the first polarizing plate 15 of the transmissive liquid crystal panel 22. As a result, the modulated first polarized light P1 of ML(R), ML(G), and ML(B) is emitted from the transmissive liquid crystal panel 22 in parallel. However, the sub-pixel PXs(T) is in the OFF state and does not transmit the illumination light. The image light ML(R), ML(G), and ML(B) emitted from each sub-pixel PXs(R), PXs(G), and PXs(B) of the transmissive liquid crystal panel 22 is incident on the switch 1 / 2 wavelength plate 23 in the OFF state. The switch 1 / 2 wavelength plate 23 allows the image light ML(R), ML(G), and ML(B) of the first polarized light P1 to pass through while maintaining its polarization direction. The image light ML(R), ML(G), and ML(B) of the first polarized light P1 that has passed through the switch 1 / 2 wavelength plate 23 forms a virtual image via the polarization lens 50 that functions as a convex lens with respect to the first polarized light P1.

[0086] On the other hand, during Figure 13During the external light observation shown, the light source 10 is in a non-luminous state, i.e., an extinguished state, and the supply of the illumination light IL to the light guide member 21 is stopped. The external light OL is incident on the transmission region 12a of the scattering member 12 and passes through the light guide plate 11. Thus, the external light OL travels straight in a manner intersecting the light guide member 21 and is incident on the transmissive liquid crystal panel 22. At this time, the sub-pixels PXs(R), PXs(G), PXs(B), and PXs(T) of each pixel PX constituting the transmissive liquid crystal panel 22 are, for example, driven to a maximum transmission state, and the second polarized light P2 in the external light OL travels straight through the transmissive liquid crystal panel 22, i.e., the sub-pixels PXs(R), PXs(G), PXs(B), and PXs(T), and is converted into the first polarized light P1 and is incident on the switch 1 / 2 wavelength plate 23. The ON-state switch 1 / 2 wavelength plate 23 rotates the polarization direction of the external light OL of the first polarized light P1 by 90° and emits it as the second polarized light P2. The external light OL of the second polarized light P2 that has passed through the switch 1 / 2 wavelength plate 23 is incident on the eye EY via the polarization lens 50 that functions as a parallel plate with respect to the second polarized light P2 without being affected by the imaging action of the composite display member 20 and the polarization lens 50.

[0087] Figure 15 It is a timing chart for explaining the display operation of the first virtual image display device 100A. Figure 15 It is for Figure 11 a diagram in which a W drive signal SM4 for the sub-pixel PXs(T) is added to the same drive signal.

[0088] The first virtual image display device 100A simultaneously and juxtaposedly displays three-color image lights ML(R), ML(G), and ML(B). In the present embodiment, during the second sub-frame Z2 for external light observation, the drive circuit 81 outputs not only the drive signals SM1 to SM3 to the sub-pixels PXs(R), PXs(G), and PXs(B) but also the W drive signal SM4 to the sub-pixel PXs(T) for the external light OL. 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 passes through the sub-pixels PXs(R), PXs(G), and PXs(B) of the transmissive liquid crystal panel 22 with good balance, so that an uncolored external image can be observed. In addition, since the external light OL also passes through the sub-pixel PXs(T) of the transmissive liquid crystal panel 22, the perspective image can be made brighter.

[0089] 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. The transmissive liquid crystal panel 22 has red, green, and blue sub-pixels PXs(R), PXs(G), and PXs(B). Corresponding to the light emission of the light source 10, modulation is performed using the sub-pixels PXs(R), PXs(G), and PXs(B) of each color. When the light source 10 does not emit light, the colorless sub-pixel PXs(T) is made to be in a transmissive state. In this case, in the first sub-frame Z1 which is a sub-frame for image observation, it is possible to simultaneously display red, green, and blue image lights ML(R), ML(G), and ML(B). 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 is possible to perform time-division observation of a color image and a perspective image.

[0090] Modification examples and others

[0091] The present invention has been described based on the above embodiments, but the present invention is not limited to the above embodiments and can be implemented in various ways without departing from its gist. For example, the following modifications can also be made.

[0092] In the scattering member 12, the scattering region 12b entirely surrounds the periphery of the transmissive region 12a, but it may not entirely surround it. In addition, the configurations of the transmissive region 12a and the scattering region 12b can be appropriately changed, etc.

[0093] The scattering member 12 may not be formed by processing the surface of the light guide plate 11. For example, the scattering member 12 may also be a sheet-like member having a transmissive region 12a and a scattering region 12b pasted on the surface of the light guide plate 11.

[0094] The scattering member 12 may also be provided on both surfaces 11a and 11b of the light guide plate 11.

[0095] The liquid crystal lens serving as the polarization lens 50 is not limited to including the annular zone portion RA. As the polarization lens 50, various structures having a lens action on specific polarized light can be adopted.

[0096] Above, it is premised that the HMD 200 is used while being worn on the head, but the above virtual image display devices 100A and 100B can also be used as a hand-held display for peeping like binoculars without being worn on the head. That is, in the present invention, the head-mounted display also includes a hand-held display.

[0097] The virtual image display device in the specific mode sequentially includes, from the outside: a light guide member that transmits illumination light from a light source; a scattering member that is provided on the light guide member and has 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 a virtual image of the polarized light in the first direction and allows the polarized light in the second direction to pass through. The transmission region is arranged at a position facing either the pixels or the sub-pixels of the transmissive liquid crystal panel. In the display state, the switching 1 / 2 wavelength plate makes image light enter the polarization lens as polarized light in the first direction, and in the non-display state, it makes external light enter the polarization lens as polarized light in the second direction.

[0098] In the above virtual image display device, when the transmissive liquid crystal panel is in the display state, the switching 1 / 2 wavelength plate makes image light from the transmissive liquid crystal panel enter the polarization lens as polarized light in the first direction, and when the transmissive liquid crystal panel is in the non-display state, it makes external light that has passed through the transmissive liquid crystal panel enter the polarization lens as polarized light in the second direction. Therefore, it is possible to switch between image light and external light and perform parallel observation. That is, the transmissive liquid crystal panel can be used for both image observation and external light observation by using the scattering member, and it is possible to suppress a decrease in the perspective transmittance while ensuring the brightness of the display.

[0099] In the virtual image display device in the specific mode, the transmission region allows external light to pass through, and the scattering region scatters the illumination light.

[0100] In the virtual image display device in the specific mode, 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.

[0101] In the virtual image display device in the specific mode, the scattering region has a nano-structure that controls the scattering direction and scattering angle of the illumination light. In this case, the illumination light can be made to enter the transmissive liquid crystal panel efficiently.

[0102] In the virtual image display device in the specific mode, the scattering member is arranged on the surface of the light guide plate provided on 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 moderated, and it is easy to fabricate the scattering member and control the scattering angle.

[0103] In the virtual image display device in the specific mode, the scattering member is arranged on the surface of the light guide plate provided on the light guide member that faces the transmissive liquid crystal panel. In this case, the scattered light can be relatively concentrated in a very small area.

[0104] In the virtual image display device in a specific mode, a light source alternately generates red, green, and blue illumination lights. The transmissive liquid crystal panel has colorless pixels, which are modulated through the pixels corresponding to the colors of the illumination lights generated by the light source, and the pixels are made to be in a transmissive state when the light source does not emit light. In this case, in the sub-frame for image observation, there are display intervals for each color of the image lights of red, green, and blue.

[0105] In the virtual image display device in a specific mode, a light source generates white illumination light. The transmissive liquid crystal panel has red, green, and blue sub-pixels, which are modulated through the respective sub-pixels corresponding to the light emission of the light source, and the respective sub-pixels are made to be in a transmissive state when the light source does not emit light. In this case, in the sub-frame for image observation, red, green, and blue image lights can be displayed simultaneously.

[0106] In the virtual image display device in a specific mode, a light source generates white illumination light. The transmissive liquid crystal panel has red, green, blue, and colorless sub-pixels, which are modulated through the respective sub-pixels corresponding to the light emission of the light source, and the colorless sub-pixels are made to be in a transmissive state when the light source does not emit light. In this case, in the sub-frame for image observation, red, green, and blue image lights can be displayed simultaneously. In the sub-frame for external light observation, by at least operating the colorless sub-pixels, time-division observation of a color image and a perspective image can be performed.

[0107] In the virtual image display device in a specific mode, the transmissive liquid crystal panel makes the respective sub-pixels be in a transmissive state when the light source does not emit light. In this case, in the sub-frame for external light observation, the respective sub-pixels can be effectively utilized, and the perspective image can be made bright.

[0108] In the virtual image display device in a specific mode, the colorless sub-pixels and the respective colored sub-pixels are arranged in a stripe shape or a Bayer shape together to form pixels.

[0109] In the virtual image display device in a specific mode, a scattering member makes the illumination light passing through the scattering region incident to form an image light in the display state, and makes the external light passing through the transmissive region pass through in the non-display state.

[0110] In the virtual image display device in a specific mode, the transmissive liquid crystal panel has a liquid crystal modulation member and a pair of polarizing plates sandwiching the liquid crystal modulation member. According to the characteristics and driving method of the liquid crystal modulation member, the pair of polarizing plates are set to a direction where the polarization directions cross or a direction where the polarization directions are parallel.

[0111] In the virtual image display device in a specific mode, it further has a driving circuit, which makes the light source, the transmissive liquid crystal panel, and the switch 1 / 2 wavelength plate operate synchronously.

Claims

1. A virtual image display device, which comprises, from the outside, the following: a light guide member that transmits illumination light from a light source; A scattering component, which is arranged on the light guiding component and has a transmission area and a scattering area; A transmissive liquid crystal panel that becomes a display state and a non-display state; A switch 1 / 2 wavelength plate that switches the polarization direction of incident light into a first direction and a second direction that cross each other; and a polarizing lens having a refractive power for imaging the polarized light in the first direction as a virtual image and allowing the polarized light in the second direction to pass through; The transmissive region is arranged at a position facing any one of a pixel and a sub-pixel of the transmissive liquid crystal panel. The switching half-wave plate allows the image light to enter the polarization lens as polarized light in the first direction in the display state, and allows the external light to enter the polarization lens as polarized light in the second direction in the non-display state.

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

3. The virtual image display device according to claim 1, wherein: The scattering region is arranged around the transmission region.

4. The virtual image display device according to claim 1, wherein: The scattering region has a nanostructure for controlling a scattering direction and a scattering angle of the illumination light.

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

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

7. The virtual image display device according to claim 1, wherein: The light source switches to generate red, green and blue illumination light. The transmissive liquid crystal panel has colorless pixels, and the illumination light generated by the light source is modulated by the pixels in accordance with the color of the illumination light, and the pixels are placed in a transmissive state when the light source does not emit light.

8. The virtual image display device according to claim 1, wherein: The light source generates white illumination light, The transmissive liquid crystal panel has red, green, and blue sub-pixels, and the sub-pixels of each color are modulated in accordance with the light emitted by the light source, and the sub-pixels of each color are placed in a transmissive state when the light source does not emit light.

9. The virtual image display device according to claim 1, wherein: The light source generates white illumination light, The transmissive liquid crystal panel has red, green, blue and colorless sub-pixels, and the sub-pixels of each color are modulated in accordance with the light emitted by the light source, and the colorless sub-pixels are placed in a transmissive state when the light source does not emit light.

10. The virtual image display device according to claim 9, wherein: The transmissive liquid crystal panel sets the sub-pixels of each color to a transmissive state when the light source does not emit light.

11. The virtual image display device according to claim 9, wherein: The achromatic sub-pixels are arranged in a stripe pattern or a Bayer pattern together with the sub-pixels of each color to form the pixel.

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

13. The virtual image display device according to claim 1, wherein: The transmissive liquid crystal panel includes a liquid crystal modulation component and a pair of polarizing plates sandwiching the liquid crystal modulation component.

14. The virtual image display device according to claim 1, wherein: The virtual image display device further includes a drive circuit that operates the light source, the transmissive liquid crystal panel, and the switching half-wavelength plate in synchronization.

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