JP4341724B2 - Virtual image observation optical device - Google Patents

Description

  The present invention relates to a virtual image observation optical apparatus suitable for use in a viewfinder of a video camera, a head mounted display, and the like, and more particularly to a virtual image observation optical apparatus using a reflective spatial light modulation element.

  A spatial light modulator (SLM) is a device configured to input a video signal and modulate light for each pixel based on the image data. There are a transmission type that modulates light transmitted through the spatial light modulation element and a reflection type that modulates light reflected from the spatial light modulation element. The virtual image observation optical device of the present invention uses the latter reflective spatial light modulator.

  The spatial light modulator uses a liquid crystal, a digital micromirror, or the like. In particular, those using liquid crystal are called liquid crystal type spatial light modulators. The liquid crystal includes an optical rotation (polarization wave guide) mode type, a birefringence mode type, a light scattering mode type, and a light absorption mode type. Commonly used liquid crystals include a TN liquid crystal using an optical rotation (polarization waveguide) mode type twisted nematic (TN) operation mode, and a STN liquid crystal using a birefringence operation mode type super twisted nematic (STN) operation mode. And FLC type liquid crystal using a ferroelectric liquid crystal (FLC) mode of operation.

  The structure and operating principle of a reflective spatial light modulator using TN liquid crystal or STN liquid crystal will be described with reference to FIG. The TN or STN liquid crystal reflective spatial light modulator 90 includes a pair of electrode portions, a liquid crystal material 95 inserted between them, and a lower reflector 96. The upper electrode part includes a glass substrate 91A, an inner (lower) transparent electrode 92A, and an inner (lower) alignment film 93A, and the lower electrode part includes a glass substrate 91B and an inner (upper) electrode. It includes a transparent electrode 92B and an alignment film 93B on the inner side (upper side) thereof.

  A polarizer 94A is disposed on the outer side (upper side) of the glass substrate 91A in the upper electrode portion, and an analyzer 94B is disposed on the outer side (lower side) of the glass substrate 91B in the lower electrode portion. The polarization directions of the two polarizers 94A and 94B are orthogonal to each other.

  The alignment films 93A and 93B have a function of aligning the alignment direction of the molecules of the liquid crystal material 95, and the alignment direction of the alignment film 93A provided in the upper electrode part is the polarization direction of the polarizer 94A provided in the upper electrode part. The alignment direction of the alignment film 93B provided on the lower electrode portion is parallel to the polarization direction of the analyzer 94B provided on the lower electrode portion. That is, the alignment directions of the two alignment films 93A and 93B are orthogonal to each other.

  22A shows a voltage non-application state in which no voltage is applied to the transparent electrodes 92A and 92B, and FIG. 22B shows a voltage application state in which a voltage is applied to the transparent electrodes 92A and 92B. In the state where no voltage is applied in FIG. 22A, the orientation of the molecules of the liquid crystal material 95 is twisted, and in the state where the voltage is applied in FIG. 22B, the molecules of the liquid crystal material 95 are aligned in the vertical direction. In the case of a TN liquid crystal, the twist angle of molecules in a state where no voltage is applied is 90 degrees.

  22A, the polarization direction of the polarized light 97A from the upper polarizer 94A is rotated by being transmitted through the liquid crystal material 95. Therefore, the polarized light 97 </ b> B passes through the lower polarizer 94 </ b> B and reaches the reflection plate 96. Similarly, the polarized light 97 </ b> C reflected from the reflecting plate 96 is transmitted through the liquid crystal material 95, thereby rotating the polarization direction and transmitting through the upper polarizer 94 </ b> A. That is, it returns to the same path as the incident light.

  However, in the voltage application state of FIG. 22B, the polarization direction of the polarized light 97A from the upper polarizer 94A does not rotate by passing through the liquid crystal material 95. Therefore, this polarized light cannot pass through the lower polarizer 94B and does not reach the reflector 96. That is, the reflected light with respect to the incident light cannot be obtained.

  The structure and operating principle of a reflective spatial light modulator using FLC will be described with reference to FIG. The FLC reflective spatial light modulator 100 includes a pair of electrode portions and a liquid crystal material 105 inserted therebetween. The upper electrode part includes a glass substrate 101A, an inner (lower) transparent electrode 102A, and an inner (lower) alignment film 103A, and the lower electrode part includes a silicon substrate 101B and an inner (upper) electrode. An aluminum electrode 102B and an alignment film 103B inside (upper) thereof are included. The aluminum electrode 102B also functions as a reflective film. A polarizer 104 is disposed on the outer side (upper side) of the glass substrate 101A in the upper electrode part.

  FIG. 23A shows a first voltage direction state in which a voltage in the first direction is applied to the transparent electrode 102A and the aluminum electrode 102B, and FIG. 23B shows a voltage in the second direction applied to the transparent electrode 102A and the aluminum electrode 102B. The second voltage direction state is shown. As shown in FIG. 23C, in the first voltage direction state, the liquid crystal material 105 has no birefringence effect on the incident polarized light, but in the second voltage direction state, the liquid crystal material 105 has a birefringence effect on the incident polarized light. Indicates.

  In the first voltage direction state of FIG. 23A, since the liquid crystal material 105 does not show a birefringence effect, the polarized light 107A from the polarizer 104 transmits the liquid crystal material 105, and without changing the polarization state, the aluminum electrode (reflection) Film) 102B. The deflection 107B reflected by the aluminum electrode (reflection film) 102B passes through the liquid crystal material 105 again and reaches the polarizer 104 without changing the polarization state. That is, light having the same polarization state as that of incident light returns to the polarizer 104. Therefore, outgoing light is obtained from the polarizer 104.

  However, in the second voltage direction state of FIG. 23B, the polarized light 107A from the polarizer 104 undergoes a birefringence effect by passing through the liquid crystal material 105, and the linearly polarized light changes to circularly polarized light. The circularly polarized light reflects the aluminum electrode (reflective film) 102B, so that the rotational direction of the circularly polarized light 107B is opposite. The circularly polarized light 107 </ b> B whose rotation direction is opposite is again transmitted through the liquid crystal material 105, thereby receiving a birefringence effect and becomes linearly polarized light. This linearly polarized light is orthogonal to the polarization direction of the polarizer 104, and therefore does not pass through the polarizer 104.

  FIG. 24 shows an example of a virtual image observation optical system having a reflective spatial light modulation element using FLC (ferroelectric liquid crystal). This virtual image observation optical system includes an FLC reflection type spatial light modulator 100, a polarizer 104, a half mirror 111, and an analyzer 112. The polarization direction of the polarizer 104 and the polarization direction of the analyzer 112 are orthogonal to each other.

  The FLC reflective spatial light modulator 100 is the same as the FLC reflective spatial light modulator shown in FIG. The spatial light modulator is usually used together with a light source device for illumination. Light 107 </ b> A from an illumination light source device (not shown) reaches the half mirror 111 via the polarizer 104. The light 107 </ b> A reflected from the half mirror 111 reaches the half mirror 111 again via the FLC reflective spatial light modulator 100. The polarized light 107 </ b> B transmitted through the half mirror 111 reaches the analyzer 112.

  As described above, in the first voltage direction state, the liquid crystal material 105 does not exhibit the birefringence effect, and thus the polarized light 107A from the polarizer 104 reaches the analyzer 112 without changing the polarization state. Therefore, the light from the illumination light source device does not pass through the analyzer 112. However, in the second voltage direction state, the liquid crystal material 105 exhibits a birefringence effect, and the polarized light 107B from the polarizer 104 reaches the analyzer 112 while changing the polarization state. Therefore, the light from the illumination light source device is transmitted through the analyzer 104 and output.

  As described above, the reason for using the illumination light source device is that when the light from the illumination light source device is not subjected to the birefringence effect by the liquid crystal material 105, black display (normally black) is obtained. This is because the phase difference generated by the birefringence effect of the liquid crystal material 105 depends on the film thickness of the liquid crystal material 105 and the incident angle of incident light.

With reference to FIG. 25, an example of a virtual image observation optical device using a conventional reflective spatial light modulation element will be described. This example is an example described in Patent Document 1 , and for details, refer to the same patent. The virtual image observation optical apparatus of the present example has a cube-shaped polarizing beam splitter cube 125 (hereinafter simply referred to as a cube), and a polarizing beam splitter 125E is formed on the diagonal surface thereof.

  As shown in the drawing, the illumination light source device 121 and the polarizer 123 correspond to the first surface 125A of the cube 125, the reflective spatial light modulator 122 corresponds to the second surface 125B, and the third surface 125C. Thus, a quarter-wave plate 126 and a reflection mirror 127 are arranged.

  Light from the illumination light source device 121 passes through the polarizer 123, is deflected by the polarization beam splitter 125 </ b> E, and reaches the reflective spatial light modulator 122. The reflected spatial light modulator 122 outputs modulated reflected light. The reflected light passes through the polarizing beam splitter 125E and the quarter-wave plate 126, and reflects the concave reflecting surface of the reflecting mirror 127. This reflected light passes through the quarter-wave plate 126 again, is deflected by the polarization beam splitter 125E (reference numeral 128A), and reaches the human pupil 131 in the observation region 130.

The virtual image observation optical device of this example has the following drawbacks.
(1) A part of the light from the illumination light source device 121 directly reaches the pupil 131 as stray light as indicated by a broken line 128B. The stray light 128B becomes noise of image data displayed by the reflective spatial light modulator 122, and reduces the contrast of the image information.

(2) Since the cube-shaped polarization beam splitter cube 125 is used, the light incident surface 125A from the illumination light source device 121, the surface 125B corresponding to the reflective spatial light modulator 122, the quarter-wave plate 126, and The surface 125C corresponding to the reflection mirror 127, the surface 125D for emitting light to the observation region 130, and the polarization beam splitter surface 125E are flat surfaces, and there are few surfaces having optical degrees of freedom. Therefore, for example, when the pixel pitch of the reflective spatial light modulator 122 is small, sufficient resolution may not be obtained. (3) Assuming that the dimensions of the reflective spatial light modulator 122 are constant, the field angle must be increased in order to increase the apparent display screen dimensions. Increasing the angle of view decreases the focal length f. When the focal length f is decreased, the absolute value of the Petzval sum PS is increased. That is, the degree of curvature of the image increases.

  The Petzval sum PS is a parameter representing the flatness or curvature of the image, and is a function of the refractive index n and the focus f as shown in the following equation.

[Equation 1]
PS = Σ (1 / nf)

When the Petzval sum is zero, that is, when PS = 0, the image is flat. The larger the absolute value of the Petzval sum PS, the greater the degree of curvature of the image. In the example of FIG. 25, only the concave reflecting surface of the reflecting mirror 127 bears the refractive power of the entire optical system, and n = −1, f> 0. Therefore, Petzval sum is PS <0
It becomes.

(4) Since the polarizing beam splitter cube and the reflection mirror are separate components, the number of components increases, and the manufacturing cost and the like increase. In addition, since there is an air layer between the cube and the reflecting mirror, the focal length becomes longer than when there is no air layer.
(5) Since the polarizing beam splitter cube has a high manufacturing cost and a large weight, the manufacturing cost and the weight of the apparatus increase.

With reference to FIG. 26, another example of a virtual image observation optical apparatus using a conventional reflective spatial light modulation element will be described. This example is also an example described in the above-mentioned Patent Document 1 , and for details, refer to this patent. The virtual image observation optical device of this example is the same as the virtual image observation optical device described with reference to FIG. 25, but additionally includes a cube-shaped polarizing beam splitter cube 124 (hereinafter simply referred to as a cube) having a small size. It has a configuration.

  The small size cube 124 has the same configuration as the large size cube 125, and a polarizing beam splitter 124E is formed on the diagonal surface thereof. As shown in the drawing, the illumination light source device 121 corresponds to the first surface 124A of the small-sized cube 124, the reflective spatial light modulator 122 corresponds to the second surface 124B, and the third surface 124C. A cube 125 having a large size is arranged, and a quarter-wave plate 126 and a reflecting mirror 127 are arranged corresponding to the third surface 125C of the cube 125 having a large size.

  Light from the illumination light source device 121 is deflected by the polarization beam splitter 124E of the small cube 124 and reaches the reflective spatial light modulator 122. The reflected spatial light modulator 122 outputs modulated reflected light. The reflected light passes through the two polarizing beam splitters 124E and 125E and the quarter-wave plate 126, and reflects the concave reflecting surface of the reflecting mirror 127. This reflected light passes through the quarter-wave plate 126 again, is deflected by the polarization beam splitter 125E (reference numeral 128A), and reaches the human pupil 131 in the observation region 130.

  In the virtual image observation optical device of this example, a part of the light from the illumination light source device 121 passes through the polarization beam splitter 124E as indicated by a broken line 128B, but does not reach the observation region 130. Therefore, noise does not occur in the image data due to stray light. Therefore, in this example, among the above-mentioned three defects, the first defect (1) is avoided, but other defects still remain.

  With reference to FIG. 27, another example of a conventional virtual image observation optical system will be described. The virtual image observation optical system shown in FIG. 27A includes an illumination light source device 141, an FLC reflective spatial light modulation element 142A, a polarizing beam splitter 143, and a concave reflecting mirror 144. The polarizing beam splitter 143 of this example has a structure in which a polarizing beam splitting film is coated on a glass substrate. In the virtual image observation optical system shown in FIG. 27B, a TN crystal type reflection type spatial light modulation element 142B is used as a spatial light modulation element, and a quarter-wave plate 145 is further interposed between the polarization beam splitter 143 and the concave reflecting mirror 144. Is provided.

  Light from the illumination light source device 141 reaches the reflective spatial light modulation elements 142A and 142B via the polarization beam splitter 143. Light from the reflective spatial light modulators 142A and 142B is deflected by the polarization beam splitter 143, reflected by the concave reflecting mirror 144, and reaches the pupil 131 of the observation space 130.

In the example of FIG. 27, a plate-shaped polarizing beam splitter 143 is used instead of the cubic polarizing beam splitter cube. Accordingly, the fifth drawback described above is avoided. However, this example has the following drawbacks.
(1) When the dimensional relationship of the optical system is the same, the focal length of the reflecting mirror that generates refractive power becomes longer and the optical magnification becomes smaller than when a cube is used. As the optical magnification decreases, the apparent display image size decreases. The focal length for virtual image formation is a value obtained by dividing the physical distance between the reflective spatial light modulator and the principal point of the reflecting mirror by the refractive index of the medium between them when the virtual image distance is infinite. .
(2) In the plate-shaped polarizing beam splitter, it is difficult to increase both the P-polarized light transmittance and the S-polarized light transmittance in the entire visible light band. Even when a reflective TN liquid crystal spatial light modulator is used as the reflective spatial light modulator and a quarter-wave plate is disposed between the reflector and the polarizing beam splitter as in the example shown in FIG. 27B, Usage efficiency cannot be increased sufficiently.
(3) For example, when compared with an internally-filled polarization beam splitter whose constituent surfaces can be curved, there are few surfaces having a free surface optical degree of freedom. Therefore, aberration correction such as resolution and field curvature may not be sufficiently achieved.

US Pat. No. 5,596,451

With reference to Figure 28 illustrating another example of imaginary image observation optical system. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a reflective spatial light modulator 20, first and second half mirrors 21 and 22, and a concave reflecting mirror 23.

  The virtual image observation optical apparatus further includes a control circuit including a system controller 2 for inputting the video signal 1, an illumination light source device driving circuit 4 for inputting a signal from the system controller 2, and a reflective spatial light modulator driving circuit 6. . The illumination light source device drive circuit 4 supplies a light source drive signal to the illumination light source device 10 based on the signal from the system controller 2, and the reflective spatial light modulator drive circuit 6 is based on the signal from the system controller 2. A drive signal is supplied to the reflective spatial light modulator 20.

  The illumination light source device 10 includes a light source 11, a reflector 12, a light guide plate 13, and a reflection plate 14. Light from the light source 11 is introduced into the light guide plate 13 directly or after being reflected by the reflector 12. A part of the light introduced into the light guide plate 13 is directly emitted from the front surface 13A, but the other part is emitted from the front surface 13A after being repeatedly reflected between the two surfaces 13A and 13B and the reflection plate 14. . By making the cross section of the light guide plate 13 into a wedge shape, the intensity of light emitted from the front surface 13 </ b> A of the light guide plate 13 is made uniform from a portion near to the light source 11 to a portion far from the light source 11.

  The light from the light guide plate 13 reaches the optical film 15. The optical film 15 has a function of controlling the divergence angle DA of the light beam from the light guide plate 13, and its performance is represented by a half-value divergence angle HDA. The half-value divergence angle HDA is an angle that is half the solid angle at which the light intensity becomes half of the peak value.

  The light that has passed through the optical film 15 is reflected by the first half mirror 21, reaches the reflective spatial light modulator 20, and is modulated thereby. The light from the reflective spatial light modulator 20 is transmitted through the first half mirror 21, reflected from the second half mirror 22, reflected from the concave reflecting mirror 23, and transmitted through the second half mirror 22. The pupil 131 of the space 130 is reached.

  FIG. 29 is a diagram schematically showing an optical system of the virtual image observation optical apparatus of FIG. The optical system of the virtual image observation optical apparatus shown in FIG. 28 will be described in detail with reference to FIG. As is apparent from this figure, the optical system of the virtual image observation optical apparatus basically includes a light source optical system and an eyepiece optical system. The light source optical system includes a light beam splitting element for guiding light from the illumination light source device 10 to the reflective spatial light modulator 20, that is, a first half mirror 21. The eyepiece optical system includes a light beam splitting element that deflects light from the reflective spatial light modulator 20, that is, a second half mirror 22 and a reflective element, that is, a concave reflecting mirror 23.

  The angle formed by the reflective spatial light modulator 20 and the light beam splitting element of the light source optical system, that is, the first half mirror 21, is α. A point at which the light beam passing through the center of the reflective spatial light modulator 20, that is, the principal ray intersects with the light beam splitting element of the eyepiece optical system, that is, the second half mirror 22 is defined as P. Let Q be the point of intersection with the concave reflecting mirror 23.

  The surface normal vector at the point P is A, the surface normal vector at the point Q is B, and the angle formed by the two vectors A and B is β. In this example, α is 45 degrees and β is 135 degrees. As shown in the figure, the angle formed by the vector B and the light beam splitting element 22 of the eyepiece optical system is 45 degrees.

  The distance between the point Q on the reflection element 23 of the eyepiece optical system and the point P on the light beam splitting element 22 is f1 ′, and the distance from the reflective spatial light modulator 20 to the point P on the light beam splitting element 22 is f2. ′. The focal length f ′ of the reflecting element, that is, the concave reflecting mirror 23 is equal to the sum of these two distances.

[Equation 2]
f ′ = f1 ′ + f2 ′

  The distance from the point Q on the reflecting element 23 of the eyepiece optical system to the light beam splitting element, that is, the lower end of the second half mirror 22, is L ′, and the lower end of the second half mirror 22 to the pupil O of the observation space 130 Is the distance R ′. The distance L ′ represents the thickness of the optical system, and the distance R ′ represents the eye relief.

  This example has a drawback that the focal length f ′ is relatively long. Further, the angle β between the two vectors A and B described above is relatively small, for example, 135 degrees. Therefore, the thickness distance L ′ of the optical system cannot be reduced. Furthermore, the eye relief or distance R ′ could not be increased.

In view of the above problems, an object of the present invention is to minimize noise in image data due to stray light in a virtual image observation optical apparatus using a reflective spatial light modulation element.

  An object of the present invention is to reduce the focal length of a reflecting element of an eyepiece optical system and increase the magnification of the optical system in a virtual image observation optical apparatus using a reflective spatial light modulation element.

  An object of the present invention is to minimize the thickness of an optical system and reduce the size of the entire apparatus in a virtual image observation optical apparatus using a reflective spatial light modulation element.

  An object of the present invention is to increase eye relief in a virtual image observation optical apparatus using a reflective spatial light modulator.

  An object of the present invention is to reduce aberration of an optical system in a virtual image observation optical apparatus using a reflective spatial light modulation element.

Virtual image optical system according to the present invention, the reflection type spatial light modulation element, the reflection type spatial light and illuminating light source device for providing illumination light to the modulation device, the illumination light emitted from the illuminating light source device is disposed on the optical path of the line, a light source optical system including a light-flux splitter having a first beam splitting surface for reflecting the illuminating light from the illuminating light source device leads to the reflective spatial light modulator, the upper The image light beam modulated by the reflective spatial light modulator is disposed on the exit side that has passed through the light beam splitting element, the refractive surface on the incident side of the image light beam from the reflective spatial light modulator, and the refractive surface a second beam splitting surface that totally reflects the incident the image light, the second reflecting the image light rays totally reflected by the beam splitting surface, observed by transmission refractive over SL second beam splitting surface leading to the space, freedom songs Menmata reflective B includes a total reflection refractive optical element and a graphic plane by Ri made reflecting surface, a normal line of the reflecting surface at a point where the principal ray passing through the center of the reflective spatial light modulator is reflected by the reflecting surface and a vector, the angle between the normal vector of the second beam splitting surface principal ray passing through the center is at the point to be reflected by the second beam splitting surface of the reflective spatial light modulator, the reflection surface The principal ray passing through the center of the reflective spatial light modulation element is 136 degrees or more and 179 degrees or less, with the side on which the light beam is reflected on each surface of the second light beam splitting surface being a positive direction of the vector. Of the light rays that pass through the optical path from the illumination light source device to the light beam dividing element, the light rays that pass through the light beam dividing element without being reflected by the light beam dividing element are reflected on the refractive surface of the total reflection refractive optical element. Incident to as reflected by the reflecting surface, and the refractive surface of the total reflection refractive optical element, and the said first beam splitting surface of the beam splitting element above Symbol light source optical system is arranged, the Of the light rays that pass through the optical path from the illumination light source device to the light beam splitting element, the main light beam that passes through the center of the reflective spatial light modulation element passes through the light beam splitting device without being reflected by the light beam splitting device, After being reflected by the reflection surface of the total reflection / refraction optical element, the optical path of the light beam directed to the second light beam splitting surface is directed to a region outside the observation space.

  Therefore, according to the present invention, the angle β formed by the surface normal vector set on the light beam splitting element and the surface normal vector set on the reflecting element is not less than 136 degrees and not more than 179 degrees. Greater than degree. Therefore, stray light from the illumination light source device does not reach the observation space. Further, the size of the optical system can be made smaller than that of a conventional virtual image observation optical device.

  According to the present invention, for example, as shown in FIG. 3, the virtual image observation optical device includes a reflective spatial light modulation element, an illumination light source device for providing illumination light to the reflective spatial light modulation element, A light source optical system for guiding illumination light from the illumination light source device to the reflective spatial light modulator; and an eyepiece optical system for guiding image light from the reflective spatial light modulator to the observation space. The light source optical system includes a light beam splitting element for deflecting the illumination light from the illumination light source device and guiding it to the reflective spatial light modulation element, and the eyepiece optical system has a refractive index larger than 1 inside. A refractive optical element filled with a medium, the eyepiece optical system refractive optical element comprising a refractive surface for receiving an image light beam from the reflective spatial light modulator, a light beam splitting surface for deflecting the image light beam, and the Depending on the beam splitting surface The deflected light is reflected and a reflecting surface for directing to the observation space.

  Thus, according to the present invention, since the optical system is constituted by a refractive optical element, each surface of the refractive optical element can be a curved surface, for example, a free curved surface having no rotational symmetry axis or an aspherical surface having a rotational symmetry axis. . Thereby, an aberration correction function and refractive power can be imparted to each surface of the refractive optical element.

  According to the present invention, for example, as shown in FIG. 5, the virtual image observation optical device includes a reflective spatial light modulation element, an illumination light source device for providing illumination light to the reflective spatial light modulation element, A light source optical system for guiding illumination light from the illumination light source device to the reflective spatial light modulator; and an eyepiece optical system for guiding image light from the reflective spatial light modulator to the observation space. The light source optical system and the eyepiece optical system each include a refractive optical element filled with a medium having a refractive index larger than 1, and the light source optical system refractive optical element receives illumination light from the illumination light source device. A first refracting surface for receiving, a second refracting surface for receiving image light from the reflective spatial light modulator, and an illuminating light beam from the illumination light source device to deflect the reflective spatial light modulator. To lead to The eyepiece optical system refracting optical element includes a refractive surface for receiving the image light beam, a light beam splitting surface for deflecting the image light beam, and reflecting light deflected by the light beam splitting surface. And a reflecting surface for guiding to the observation space.

  According to the present invention, since the optical system has an integrated structure as one refractive optical element by joining the light source optical system refractive optical element and the eyepiece optical system refractive optical element, the manufacturing process is simplified, and a virtual image of a compact structure is obtained. An observation optical system is obtained.

  According to the present invention, for example, as shown in FIG. 7, a virtual image observation optical device includes a reflective spatial light modulation element, an illumination light source device for providing illumination light to the reflective spatial light modulation element, A light source optical system for guiding illumination light from the illumination light source device to the reflective spatial light modulator; and an eyepiece optical system for guiding image light from the reflective spatial light modulator to the observation space. The light source optical system includes a refractive optical element filled with a medium having a refractive index larger than 1, and the eyepiece optical system includes two refractive optical elements filled with a medium having a refractive index larger than 1. The light source optical system refractive optical element includes a first refractive surface for receiving an illumination light beam from the illumination light source device, and a second refractive surface for receiving an image light beam from the reflective spatial light modulator. Lighting light A light splitting surface for deflecting an illumination light beam from the apparatus and guiding it to the reflective spatial light modulator, wherein the first refractive optical element of the eyepiece optical system receives the image light from the light source optical system refractive optical element An eyepiece optical system including a refracting surface for receiving, a light beam splitting surface for deflecting the image light beam, and a reflecting surface for reflecting light deflected by the light beam splitting surface and guiding it again to the light beam splitting surface The second refractive optical element receives the light from the light splitting surface of the first refractive optical element of the first eyepiece optical system and the light from the first refractive surface to the observation space. A second refractive surface for guiding.

  The light source optical system refractive optical element and the first and second refractive optical elements of the eyepiece optical system are optically closely bonded.

  According to the present invention, the refractive optical element of the light source optical system and the refractive optical element of the eyepiece optical system can be composed of one or two refractive optical elements joined to each other. Simplified and miniaturized.

  According to the present invention, for example, as shown in FIG. 8, a virtual image observation optical device includes a reflective spatial light modulation element, an illumination light source device for providing illumination light to the reflective spatial light modulation element, A light source optical system for guiding illumination light from the illumination light source device to the reflective spatial light modulator; and an eyepiece optical system for guiding image light from the reflective spatial light modulator to the observation space. The light source optical system includes a refractive optical element filled with a medium having a refractive index larger than 1, and the eyepiece optical system includes two refractive optical elements filled with a medium having a refractive index larger than 1. The light source optical system refractive optical element includes a first refractive surface for receiving an illumination light beam from the illumination light source device, and a second refractive surface for receiving an image light beam from the reflective spatial light modulator. Lighting light A light splitting surface for deflecting an illumination light beam from the apparatus and guiding it to the reflective spatial light modulator, wherein the first refractive optical element of the eyepiece optical system receives the image light from the light source optical system refractive optical element An eyepiece optical system including a refracting surface for receiving, a light beam splitting surface for deflecting the image light beam, and a reflecting surface for reflecting light deflected by the light beam splitting surface and guiding it again to the light beam splitting surface The second refractive optical element receives the light from the light splitting surface of the first refractive optical element of the first eyepiece optical system and the light from the first refractive surface to the observation space. A second refractive surface for guiding.

  According to the present invention, the optical system includes two refractive optical elements, ie, a light source optical system refractive optical element and an eyepiece optical system, and has a large number of optical surfaces. Accordingly, by making each surface of these refractive optical elements a curved surface such as a free curved surface, a spherical surface, or an aspherical surface, aberration can be reduced and refractive power can be imparted. Further, a polarizer, an analyzer, a quarter-wave plate, or the like can be disposed between the refractive optical element and the refractive optical element.

  According to the present invention, for example, as shown in FIGS. 9 and 10, the virtual image observation optical device includes a reflective spatial light modulation element and an illumination light source for providing illumination light to the reflective spatial light modulation element. Device, light source optical system for guiding illumination light from the illumination light source device to the reflective spatial light modulator, and eyepiece optical system for guiding image light from the reflective spatial light modulator to the observation space The light source optical system includes a light beam splitting element for deflecting the illumination light from the illumination light source device and guiding it to the reflective spatial light modulator, and the eyepiece optical system has a refractive index inside. A refractive optical element filled with a medium greater than 1, the eyepiece optical system refractive optical element for deflecting the image light beam with a first refractive surface for receiving the image light beam from the reflective spatial light modulator. Luminous flux splitting surface and the A reflecting surface for reflecting the light deflected by the bundle splitting surface and a second refracting surface for guiding the light from the reflecting surface to the observation space, wherein the first and second refracting surfaces are: It is formed in a rotationally symmetric curved surface having a principal ray passing through the center of the reflective spatial light modulator as a rotational symmetry axis.

  Therefore, according to the present invention, since the eyepiece optical system is formed of one refractive optical element, the assembly process of the virtual image observation optical device is simplified. Various aberrations can be removed by making the refracting and reflecting surfaces of the refractive optical element of the eyepiece optical system curved.

  According to the present invention, the angle β formed by the surface normal vector A standing on the light beam splitting element of the eyepiece optical system and the surface normal vector B standing on the reflecting element is not less than 136 degrees and not more than 179 degrees. There is an advantage that it is possible to provide a virtual image observing optical apparatus in which the above is reduced.

  According to the present invention, the angle β formed by the surface normal vector A standing on the light beam splitting element of the eyepiece optical system and the surface normal vector B standing on the reflecting element is not less than 136 degrees and not more than 179 degrees. There is an advantage that a virtual image observation optical device can be provided.

  According to the present invention, the angle β formed by the surface normal vector A standing on the light beam splitting element of the eyepiece optical system and the surface normal vector B standing on the reflecting element is not less than 136 degrees and not more than 179 degrees. There is an advantage that a high-resolution virtual image observation optical apparatus can be provided.

  According to the present invention, one of the refractive optical elements of the optical system has a sufficiently small birefringence (usually made of glass), thereby minimizing the deterioration of the contrast of the display image. There is an advantage that can be. Therefore, it has an advantage that the manufacturing cost and the weight of the optical system can be reduced as compared with the case where all the refractive optical elements constituting the optical system are made to have a sufficiently small birefringence (usually made of glass).

  According to the present invention, the assembly process can be simplified by providing the light beam splitting element or reflecting element of the optical system on one surface of the refractive optical element.

  According to the present invention, curvature of field and distortion can be corrected by forming each surface of the refractive optical element into an appropriately shaped free-form surface or aspheric surface. Therefore, there is an advantage that a high-resolution virtual image observation optical apparatus can be provided.

It is a figure which shows the 1st example of the virtual image observation optical apparatus of this invention. It is explanatory drawing for demonstrating the detail of the 1st example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 2nd example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 3rd example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 4th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 5th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 6th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 7th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 8th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the 9th example of the virtual image observation optical apparatus of this invention. It is a light ray figure of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the data of the optical system of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the lens data of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the light ray aberration of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the light ray aberration of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the light ray aberration of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the light ray aberration of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows the light ray aberration of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows MTF of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows MTF of the 10th example of the virtual image observation optical apparatus of this invention. It is a figure which shows MTF of the 10th example of the virtual image observation optical apparatus of this invention. It is explanatory drawing for demonstrating a structure and operation | movement of a reflection type spatial light modulation element using an optical rotation (polarization waveguide) type liquid crystal. It is explanatory drawing for demonstrating the structure and operation | movement of a reflection type spatial light modulation element using a birefringent liquid crystal (FLC). It is explanatory drawing for demonstrating the outline of a structure of the virtual image observation optical system using the reflection type spatial light modulation element using the conventional birefringent liquid crystal (FLC). It is a figure which shows the 1st example of the conventional virtual image observation optical apparatus. It is a figure which shows the 2nd example of the conventional virtual image observation optical apparatus. It is a figure which shows the 3rd and 4th example of the conventional virtual image observation optical apparatus. Is a diagram illustrating an example of the imaginary image observation optical system. It is an explanatory view for explaining an example details of the imaginary image observation optical device shown in FIG. 28.

  A first example of the virtual image observation optical apparatus of the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a reflective spatial light modulator 20, first and second half mirrors 21 and 22, and a concave reflecting mirror 23.

  The half mirrors 21 and 22 may be reflective hologram surfaces. A polarizing beam splitter may be provided instead of the half mirrors 21 and 22, and a quarter-wave plate may be provided as appropriate. The concave reflecting mirror 23 may be a reflective holographic surface, and may be formed as an aspherical surface. The aspherical surface means a non-spherical curved surface having a rotational symmetry axis. Furthermore, the concave reflecting mirror 23 may be a free-form surface having no rotational symmetry axis. Although not shown, a polarizer and an analyzer may be provided.

  The virtual image observation optical apparatus further includes a control circuit including a system controller 2 for inputting the video signal 1, an illumination light source device driving circuit 4 for inputting a signal from the system controller 2, and a reflective spatial light modulator driving circuit 6. .

  The illumination light source device 10 includes a light source 11, a reflector 12, a light guide plate 13, and a reflection plate 14.

Components of the virtual image optical system of the present embodiment may be similar to the components of the reference to imaginary image observation optical device described Figure 28. However, the relative positional relationship between the components of the virtual image observation optical apparatus of this example is different from the example of FIG.

As in the case of the example of FIG. 28 , a part of the light from the illumination light source device 10 reflects the first half mirror 21 and reaches the reflective spatial light modulator 20, but the other part is the first. , And reaches the concave reflecting mirror 23 and reflects it. However, in this example, the stray light 200 reflected by the concave reflecting mirror 23 does not reach the pupil 131 of the observation space 130. Therefore, in this example, noise with respect to image data is not generated by the stray light 200.

  Details of the operation of the optical system of the virtual image observation optical apparatus of FIG. 1 will be described with reference to FIG. FIG. 2 is a diagram corresponding to FIG. 29, and the same portions are denoted by the same reference numerals. As in the example of FIG. 29, the optical system of this example guides light from the illumination light source device 10 to the reflective spatial light modulator 20 and guides light from the reflective spatial light modulator 20 to the eyepiece optical system. And an eyepiece optical system for guiding the light from the light source optical system to the pupil 131 of the observation space 130.

  The light source optical system includes a light beam splitting element 21 for deflecting light from the illumination light source device 10 and guiding it to the reflective spatial light modulation element 20. The eyepiece optical system includes a light beam splitting element 22 for deflecting light from the light source optical system and a reflecting element 23 for guiding light from the light beam splitting element 22 to the pupil 131 of the observation space 130.

  In this example, the first half mirror 21 is a light beam splitting element of the light source optical system, and the angle formed by the first half mirror 21 and the reflective spatial light modulator 20 is α. The second half mirror 22 is a light beam splitting element of the eyepiece optical system, and the concave reflecting mirror 23 is a reflecting element. Therefore, the angle formed by the surface normal vector A raised on the second half mirror 22 and the surface normal vector B raised on the concave reflecting mirror 23 is β.

In this example, α is 45 degrees and β is 145 degrees. The angle formed by the vector B and the second half mirror 22 is 55 degrees. The angle β formed by the two vectors A and B in this example is larger than the angle β formed by the two vectors A and B in the examples shown in FIGS.

  Similarly, the distance between the point Q on the concave reflecting mirror 23 and the point P on the second half mirror 22 is f1, and the distance from the reflective spatial light modulator 20 to the point P on the second half mirror 22 is Let the distance be f2. The focal length f of the concave reflecting mirror 23 is equal to the sum of these two distances.

[Equation 3]
f = f1 + f2

When the value of the focal length f of the concave reflecting mirror 23 of this example is compared with the value of the focal length f ′ of the concave reflecting mirror 23 of the example of FIG. 29, the value of the focal length f of the concave reflecting mirror 23 of this example is greater. Smaller than.

[Equation 4]
f <f ′

  Therefore, in the virtual image observation optical device of this example, the magnification of the optical system can be made larger than in the conventional case.

  The distance from the point Q on the concave reflecting mirror 23 to the lower end of the second half mirror 22 is L, and the distance from the lower end of the second half mirror 22 to the pupil O of the observation space 130 is R. The distance L represents the thickness of the optical system, and the distance R represents the eye relief.

When the values of the thickness L and the eye relief R of the optical system of this example are compared with the values of the thickness L ′ and the eye relief R ′ of the optical system of the example of FIG. 29, respectively, the thickness L of the optical system of this example is compared. Is smaller, and the eye relief R in this example is larger.

[Equation 5]
L <L '
R> R '

An embodiment based on the first example of the virtual image observation optical apparatus according to the present invention shown in FIG. 1 is as follows.
(1) Illumination light source device 10
(A) Light source 11: Cold cathode tube (b) Optical film 15: Half-value divergence angle HDA≈15 °
(2) Reflective spatial light modulator 20
(A) Liquid crystal: TN type (b) Display unit: Diagonal length DL = 0.55 inch (c) Pixel: VGA 640 × 480
(3) Arrangement of optical system (a) Light beam splitting element of light source optical system = first half mirror 21
α ≒ 45 °
(B) The beam splitting element of the eyepiece optical system = the second half mirror 22
Reflective element = concave reflector 23
β ≒ 145 °

  A second example of the virtual image observation optical apparatus according to the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a polarizer 17, a reflective spatial light modulator 20, a polarization beam splitter 25, an analyzer 26, and a total reflection / refractive optical element 30. The polarization beam splitter 25 may be a reflection hologram, for example. Although not shown, a quarter wave plate may be provided as appropriate. The illumination light source device 10 of this example may be the same as the illumination light source device 10 of the first example of FIG.

  The analyzer 26 is provided to improve the contrast of the display image and to reduce stray light, and the polarization direction thereof is arranged to be orthogonal to the polarization direction of the polarizer 17, that is, to have a crossed Nicols relationship. Has been.

  The eyepiece optical system of this example is constituted by a total reflection / refraction optical element 30. Here, the refractive optical element is an optical element having a plurality of refracting surfaces and reflecting surfaces like a prism. The prism has a plurality of optical planes, whereas the refractive optical element has a plurality of optical planes or curved surfaces. Have The total catadioptric optical element 30 has a structure filled with a medium having a refractive index greater than 1, and has a concave refracting surface 31, a planar light beam splitting surface 32, and a concave reflecting surface 33 inside. The refracting surface 31 and the reflecting surface 33 have free curved surfaces in order to reduce non-rotationally symmetric aberration. A free-form surface means a curved surface shape having no rotational symmetry axis. The reflective surface 33 may be formed by a reflective holographic surface.

  The virtual image observation optical device of this example further includes a control circuit including a system controller 2, an illumination light source device drive circuit 4, and a reflective spatial light modulator drive circuit 6.

  The light from the illumination light source device 10 passes through the optical film 15 and the polarizer 17, reflects off the polarization beam splitter 25, and reaches the reflective spatial light modulator 20. The light from the reflective spatial light modulator 20 reaches the total reflection / refractive optical element 30 via the polarization beam splitter 25 and the analyzer 26.

  The light passing through the refracting surface 31 of the total reflection / refractive optical element 30 is reflected by the light beam splitting surface 32 under the total reflection condition and reaches the reflection surface 33. The light reflected from the reflecting surface 33 reaches the pupil 131 of the observation space 130 via the light beam splitting surface 32.

  Next, stray light in this example will be described. A part of the light from the illumination light source device 10 passes through the polarization beam splitter 25 and the analyzer 26 and is reflected by the reflection surface 33 of the total reflection / refraction optical element 30. The stray light 200 reflected from the reflecting surface 33 is deflected in a direction away from the observation space 130 through the light beam splitting surface 32. Therefore, the stray light 200 does not reach the pupil 131 of the observation space 130.

  In this example, the polarization beam splitter 25 is a light beam splitting element of the light source optical system, and the angle formed between the polarization beam splitter 25 and the reflective spatial light modulator 20 is α. The light splitting surface 32 of the total catadioptric optical element 30 is a light splitting element of the eyepiece optical system, and the reflecting surface 33 is a reflecting element. Therefore, the angle formed by the surface normal vector A raised on the light beam splitting surface 32 of the total catadioptric optical element 30 and the surface normal vector B raised on the reflecting surface 33 is β.

  A third example of the virtual image observation optical apparatus according to the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a polarizer 17, a reflective spatial light modulator 20, a polarizing beam splitter 25, an analyzer 26, a total reflection refractive optical element 30-1, and a refractive optical device. Element 30-2.

  The virtual image observation optical device of this example is different from the virtual image observation optical device of the second example of FIG. 3 in that a refractive optical element 30-2 is added, and other configurations are the same as those of the second example. It may be. Therefore, the description of the configuration other than the refractive optical element 30-2 is omitted here.

  The eyepiece optical system of this example includes a total reflection / refractive optical element 30-1 and a refractive optical element 30-2. The refractive optical element 30-2 has first and second refracting surfaces 34 and 35, which may be formed in a free-form surface having no rotational symmetry axis.

  The stray light in this example will be described. A part of the light from the illumination light source device 10 passes through the polarization beam splitter 25 and the analyzer 26 and is reflected by the reflection surface 33 of the total reflection / refraction optical element 30-1. The stray light 200 reflected from the reflecting surface 33 is deflected in a direction away from the observation space 130 via the light beam splitting surface 32 and the refractive optical element 30-2. Therefore, the stray light 200 does not reach the pupil 131 of the observation space 130.

  In this example, as in the second example, the polarizing beam splitter 25 is a light beam splitting element of the light source optical system, and the angle formed by the polarizing beam splitter 25 and the reflective spatial light modulator 20 is α. The light splitting surface 32 of the total catadioptric optical element 30-1 is a light splitting element of the eyepiece optical system, and the reflecting surface 33 is a reflecting element. Therefore, the angle formed by the surface normal vector A raised on the light beam splitting surface 32 of the total catadioptric optical element 30-1 and the surface normal vector B raised on the reflecting surface 33 is β.

Embodiments based on the second and third examples of the virtual image observation optical apparatus according to the present invention shown in FIGS. 3 and 4 are as follows.
(1) Illumination light source device 10
(A) Light source 11: Light emitting diode (LED)
(B) Optical film 15: Half-value divergence angle HDA≈15 °
(2) Reflective spatial light modulator 20
(A) Liquid crystal: FLC type (b) Display unit: diagonal length DL = 0.55 inch (c) Pixel: VGA 640 × 480
(3) Arrangement of optical system (a) Light beam splitting element of light source optical system = polarizing beam splitter 25
α ≒ 45 °
(B) The light beam splitting element of the eyepiece optical system = the light beam splitting surface 32 of the total reflection / refractive optical elements 30 and 30-1.
Reflective element = reflective surface 33 of total reflection / refractive optical elements 30, 30-1.
β ≒ 145 °

  A fourth example of the virtual image observation optical apparatus according to the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a reflective spatial light modulator 20, a refractive optical element 40-1, and a total reflection refractive optical element 40-2.

  According to this example, the light source optical system is constituted by the refractive optical element 40-1, and the eyepiece optical system is constituted by the total reflection refractive optical element 40-2.

  The refracting optical element 40-1 has concave first and second refracting surfaces 41 and 43 and a half mirror. The half mirror 42 may be a reflection hologram surface. The total catadioptric optical element 40-2 has a refracting surface 44, a flat light splitting surface 47, and a concave reflecting surface 48 inside.

  Although the refractive optical element 40-1 and the total reflection refractive optical element 40-2 may be configured as separate refractive optical elements, they may be optically closely bonded via the half mirror 42 and the refractive surface 44. When the two refractive optical elements 40-1 and 40-2 are optically closely joined, the half mirror 42 and the refractive surface 44 are surfaces formed inside the refractive optical elements 40-1 and 40-2. .

  The light source optical system and the eyepiece optical system configured by the refractive optical element 40-1 and the total reflection refractive optical element 40-2 are decentered optical systems. Accordingly, the first and second refracting surfaces 41 and 43 of the refractive optical element 40-1 and the reflecting surface 48 of the total reflection refracting optical element 40-2 are formed as free-form surfaces in order to reduce non-rotationally symmetric aberration. Yes. The reflection surface 48 of the total catadioptric optical element 40-2 may be, for example, a reflective holographic surface. Instead of the half mirror 42, a polarizing beam splitter may be provided and a quarter wave plate may be provided. Although not shown, a polarizer and an analyzer may be provided as appropriate.

  Light from the illumination light source device 10 passes through the optical film 15, passes through the first refractive surface 41 of the refractive optical element 40-1, reflects the half mirror 42, and passes through the second refractive surface 43. The reflection type spatial light modulator 20 is reached. The light from the reflective spatial light modulator 20 reaches the total reflection refractive optical element 40-2 via the second refractive surface 43 and the half mirror 42 of the refractive optical element 40-1.

  The light that reaches the total reflection / refraction optical element 40-2 passes through the refractive surface 44 and is reflected by the light beam splitting surface 47 of the total reflection / refraction optical element 40-2 under the total reflection condition. The light reflected by the light beam splitting surface 47 is reflected by the reflecting surface 48 and reaches the pupil 131 of the observation space 130 via the light beam splitting surface 47.

  Next, stray light in this example will be described. A part of the light from the illumination light source device 10 passes through the half mirror 42 and the refracting surface 44 and reflects off the reflecting surface 48 of the total reflection / refractive optical element 40-2. The stray light 200 reflected from the reflecting surface 48 is deflected in a direction away from the observation space 130 through the light beam splitting surface 47. Therefore, in this example, the stray light 200 does not reach the pupil 131 of the observation space 130.

  In this example, the half mirror 42 of the refractive optical element 40-1 is a light beam splitting element of the light source optical system. Therefore, the angle formed by the half mirror 42 and the reflective spatial light modulator 20 is α. Further, the light beam splitting surface 47 of the total catadioptric optical element 40-2 is a light beam splitting device of the eyepiece optical system, and the reflecting surface 48 is a reflecting element. Therefore, the angle formed by the surface normal vector A raised on the light beam splitting surface 47 of the total reflection / refraction optical element 40-2 and the surface normal vector B raised on the reflection surface 48 is β.

  A fifth example of the virtual image observation optical apparatus according to the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a reflective spatial light modulator 20, a refractive optical element 40-1, a total reflection refractive optical element 40-2, and a refractive optical element 40-3. Have.

  The virtual image observation optical device of this example is different from the virtual image observation optical device of the fourth example of FIG. 5 in that a second refractive optical element 40-3 is added, and the other configuration is the same as the fourth example. It may be the same. Therefore, the description of the configuration other than the refractive optical element 40-3 is omitted here.

  The eyepiece optical system of this example is constituted by a total reflection refractive optical element 40-2 and a refractive optical element 40-3. The second refractive optical element 40-3 has first and second refracting surfaces 46, 49, which may be formed as a free-form surface having no rotational symmetry axis.

  The stray light in this example will be described. A part of the light from the illumination light source device 10 passes through the half mirror 42 and the refracting surface 44 and reflects off the reflecting surface 48 of the total reflection / refractive optical element 40-2. The stray light 200 reflected from the reflecting surface 48 is deflected in a direction away from the observation space 130 through the light beam splitting surface 47 and the refractive optical element 40-3. Therefore, the stray light 200 does not reach the pupil 131 of the observation space 130.

  In this example, as in the fourth example, the half mirror 42 is a light beam splitting element of the light source optical system, and the angle formed by the half mirror 42 and the reflective spatial light modulator 20 is α. The light splitting surface 47 of the total catadioptric optical element 40-2 is a light splitting element of the eyepiece optical system, and the reflecting surface 48 is a reflecting element. Therefore, the angle formed by the surface normal vector A raised on the light beam splitting surface 47 of the total reflection / refraction optical element 40-2 and the surface normal vector B raised on the reflection surface 48 is β.

Examples based on the fourth and fifth examples of the virtual image observation optical apparatus according to the present invention shown in FIGS. 5 and 6 are as follows.
(1) Illumination light source device 10
(A) Light source 11: Light emitting diode (LED)
(B) Optical film 15: Half-value divergence angle HDA≈15 °
(2) Reflective spatial light modulator 20
(A) Liquid crystal: TN type (b) Display unit: diagonal length DL = 0.55 inch (c) Pixel: VGA 640 × 480
(3) Arrangement of optical system (a) Light beam splitting element of light source optical system = half mirror 42 of refractive optical element 40-1
α ≒ 40 °
(B) The light beam splitting element of the eyepiece optical system = the light beam splitting surface 47 of the total internal reflection refractive optical element 40-2
Reflective element = refracting surface 48 of total reflection refractive optical element 40-2
β ≒ 140 °

  A sixth example of the virtual image observation optical apparatus according to the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a reflective spatial light modulator 20, and a glass refractive optical element 50. The glass refractive optical element 50 includes four glass refractive optical elements 50-1, 50-2, 50-3, and 50-4 as shown in the figure.

  According to this example, the light source optical system is configured by the first glass refractive optical element 50-1, and the eyepiece optical system is the second, third, and fourth glass refractive optical elements 50-2, 50-3, 50-4.

  The light source optical system has a concave first refractive surface 51, a half mirror 52, and a convex second refractive surface 53. The eyepiece optical system has a third refracting surface 54, a polarizing beam splitter 57, a quarter-wave plate 56, a concave reflecting surface 58 and a concave fourth refracting surface 59 inside. The half mirror 52 and the third refracting surface 54 may be cylindrical surfaces having a central axis perpendicular to the paper surface.

  The glass refractive optical element 50 may be composed of four separate glass refractive optical elements 50-1, 50-2, 50-3, and 50-4. It may be configured as a refractive optical element. When configured as one glass refractive optical element, the half mirror 52, the polarization beam splitter 57, and the quarter wavelength plate 56 are surfaces formed inside the glass refractive optical element 50.

  The half mirror 52 may be a reflective hologram surface. The reflective surface 58 may be, for example, a reflective holographic surface. Although not shown, a polarizer and an analyzer may be provided as appropriate.

  The first, second and third refracting surfaces 51, 53, 59 and the reflecting surface 58 of the glass refractive optical element 50 are mainly composed of aspherical surfaces in order to correct distortion and curvature of field. An aspherical surface means an aspherical curved surface having an axis of symmetry.

  The light from the illumination light source device 10 passes through the optical film 15 and reflects through the first refractive surface 51 of the glass refractive optical element 50 to the cylindrical half mirror 52. By making the half mirror 52 into a cylindrical surface, the illumination light from the illumination light source device 10 is efficiently and uniformly guided to the reflective spatial light modulator 20. The light from the half mirror 52 reaches the reflective spatial light modulator 20 via the second refracting surface 53. The light from the reflective spatial light modulator 20 reaches the half mirror 52 via the second refracting surface 53.

  The light that has passed through the half mirror 52 is reflected by the polarization beam splitter 57 and reaches the reflection surface 58 via the quarter-wave plate 56. The light reflected from the reflecting surface 58 passes through the quarter-wave plate 56 again.

  The linearly polarized light incident on the reflecting surface 58 becomes circularly polarized light by passing through the quarter-wave plate 56. The circularly polarized light reflected by the reflecting surface 58 becomes linearly polarized light by passing through the quarter-wave plate 56. The return linearly polarized light has a polarization state orthogonal to the forward linearly polarized light. The linearly polarized light from the quarter-wave plate 56 reaches the pupil 131 of the observation space 130 via the polarization beam splitter 57 and the third refracting surface 59.

  Next, stray light in this example will be described. A part of the light from the illumination light source device 10 passes through the half mirror 52 and reflects off the reflection surface 58. The stray light 200 reflected from the reflecting surface 58 is deflected away from the observation space 130 by passing through the third refracting surface 59. Therefore, in this example, the stray light 200 does not reach the pupil 131 of the observation space 130.

  In this example, the half mirror 52 of the first glass refractive optical element 50-1 is a light beam splitting element of the light source optical system. Therefore, the angle formed by the half mirror 52 and the reflective spatial light modulator 20 is α. . The polarizing beam splitter 57 of the second glass refractive optical element 50-2 is a light beam splitting element of the eyepiece optical system, and the reflecting surface 58 of the fourth glass refractive optical element 50-4 is a reflecting element. Therefore, the angle formed by the surface normal vector A raised on the polarizing beam splitter 57 and the surface normal vector B raised on the reflecting surface 58 is β.

An embodiment based on the sixth example of the virtual image observation optical apparatus according to the present invention shown in FIG. 7 is as follows.
(1) Illumination light source device 10
(A) Light source 11: Light emitting diode (LED)
(B) Optical film 15: Half-value divergence angle HDA≈20 °
(2) Reflective spatial light modulator 20
(A) Liquid crystal: TN type (b) Display unit: diagonal length DL = 0.45 inch (c) Pixel: SVGA 800 × 600
(3) Arrangement of optical system (a) Light beam splitting element of light source optical system = half mirror 52 of refractive optical element 50 made of glass
α ≒ 45 °
(B) The beam splitting element of the eyepiece optical system = the beam splitting surface 57 of the refractive optical element 50 made of glass
Reflective element = reflecting surface 58 of the refractive optical element 50 made of glass
β ≒ 145 °

  A seventh example of the virtual image observation optical apparatus according to the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a polarizer 17, a reflective spatial light modulator 20, a glass refractive optical element 60-1, and first and second plastic refractive optical elements. 60-2, 60-3.

  According to this example, the light source optical system is constituted by the glass refractive optical element 60-1, and the eyepiece optical system is constituted by the first and second plastic refractive optical elements 60-2 and 60-3. In this example, the first and second plastic refractive optical elements 60-2 and 60-3 of the eyepiece optical system may be optically closely bonded to each other to form a single refractive optical element. Further, the glass refractive optical element 60-1 and the first and second plastic refractive optical elements 60-2 and 60-3 are optically closely bonded to each other to form a single refractive optical element. Good.

  The glass refractive optical element 60-1 has a concave first refractive surface 61, a polarizing beam splitter 63, and a convex second refractive surface 62. The first plastic refractive optical element 60-2 has an analyzer 64, a half mirror 67, and a concave reflecting surface 68 inside. The second plastic refractive optical element 60-3 has a flat first refractive surface 66 and a concave second refractive surface 65.

  Refraction of the first and second refractive surfaces 61 and 62 of the glass refractive optical element 60-1, the reflecting surface 68 of the first plastic refractive optical element 60-2, and the second plastic refractive optical element 60-3. The surface 65 is aspherical. The polarizing beam splitter 63 of the glass refractive optical element 60-1 may be a reflection hologram surface. The reflective surface 68 of the first plastic refractive optical element 60-2 may be, for example, a reflective holographic surface. A polarization beam splitter may be provided instead of the half mirror 67, and a quarter wave plate may be further provided.

  The analyzer 64 is provided to improve the contrast of the display image and reduce stray light, and the polarization direction thereof is arranged to be orthogonal to the polarization direction of the polarizer 17, that is, to have a crossed Nicols relationship. Has been.

  The light from the illumination light source device 10 passes through the optical film 15 and the polarizer 17, is reflected by the polarization beam splitter 63 through the first refractive surface 61 of the glass refractive optical element 60-1, The light reaches the reflective spatial light modulator 20 via the refractive surface 62. The light from the reflective spatial light modulator 20 reaches the first plastic refractive optical element 60-2 via the second refractive surface 62 and the polarizing beam splitter 63 of the glass refractive optical element 60-1. To do.

  The light that has reached the first plastic refractive optical element 60-2 is reflected by the half mirror 67 and the reflecting surface 68 via the analyzer 64, and is transmitted through the half mirror 67 to be the second plastic refractive optical element. Reach 60-3. The light that reaches the second plastic refractive optical element 60-3 reaches the pupil 131 of the observation space 130 via the first and second refractive surfaces 66 and 65.

  Next, stray light in this example will be described. A part of the light from the illumination light source device 10 is transmitted through the polarizing beam splitter 63 of the glass refractive optical element 60-1 and reflected by the reflecting surface 68 of the first plastic refractive optical element 60-2. The stray light 200 reflected from the reflecting surface 68 is deflected away from the observation space 130 by passing through the refracting surface 65 of the second plastic refracting optical element 60-3. Therefore, in this example, the stray light 200 does not reach the pupil 131 of the observation space 130.

  In this example, the polarizing beam splitter 63 of the glass refractive optical element 60-1 is a light beam splitting element of the light source optical system. Therefore, the angle formed between the polarizing beam splitter 63 and the reflective spatial light modulator 20 is α. The half mirror 67 of the first plastic refractive optical element 60-2 is a light beam splitting element of the eyepiece optical system, and the reflecting surface 68 is a reflecting element. Therefore, the angle formed by the surface normal vector A raised on the half mirror 67 of the first plastic refractive optical element 60-2 and the surface normal vector B raised on the reflecting surface 68 is β.

An embodiment based on the seventh example of the virtual image observation optical apparatus according to the present invention shown in FIG. 8 is as follows.
(1) Illumination light source device 10
(A) Light source 11: Light emitting diode (LED)
(B) Optical film 15: Half-value divergence angle HDA≈20 °
(2) Reflective spatial light modulator 20
(A) Liquid crystal: FLC type (b) Display unit: diagonal length DL = 0.45 inch (c) Pixel: SVGA 800 × 600
(3) Arrangement of optical system (a) Light beam splitting element of light source optical system = polarizing beam splitter 63 of refractive optical element 60-1 made of glass
α ≒ 45 °
(B) Beam splitting element of eyepiece optical system = half mirror 67 of plastic refractive optical element 60-2
Reflective element = reflective surface 68 of plastic refractive optical element 60-2
β ≒ 145 °

  With reference to FIG. 9, an eighth example of the virtual image observation optical apparatus according to the present invention will be described. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a polarizer 17, a reflective spatial light modulator 20, a half mirror 21, an analyzer 26, and a plastic refractive optical element 70. According to this example, the eyepiece optical system is constituted by a plastic refractive optical element 70.

  The plastic refractive optical element 70 includes a spherical first refractive surface 71, a half mirror 72, an inner concave reflective surface 73, and an aspherical second refractive surface 74. The half mirror 72 is a surface formed inside the plastic refractive optical element 70. The half mirror 72 may be a reflective hologram surface. The reflection surface 73 may be a reflection type holographic surface and is formed in an aspherical surface. A polarizing beam splitter may be provided instead of the half mirror 72, and a quarter wavelength plate may be further provided.

  Light from the illumination light source device 10 passes through the optical film 15 and the polarizer 17, is reflected by the half mirror 21, and reaches the reflective spatial light modulator 20. The light from the reflective spatial light modulator 20 reaches the plastic refractive optical element 70 via the half mirror 21 and the analyzer 26.

  The light reaching the plastic refractive optical element 70 is reflected by the half mirror 72 and the reflecting surface 73 via the first refracting surface 71, and is observed by the observation space 130 via the half mirror 72 and the second refracting surface 74. The pupil 131 is reached.

  Next, stray light in this example will be described. A part of the light from the illumination light source device 10 passes through the half mirror 21 and the analyzer 26 and reflects on the reflection surface 73 of the plastic refractive optical element 70. However, in this example, the stray light reflected from the reflecting surface 73 of the plastic refractive optical element 70 does not reach the pupil 131 of the observation space 130.

  A ninth example of the virtual image observation optical apparatus according to the present invention will be described with reference to FIG. The virtual image observation optical device of this example includes an illumination light source device 10, an optical film 15, a polarizer 17, a reflective spatial light modulator 20, a half mirror 21, an analyzer 26, and a plastic refractive optical element 80. According to this example, the eyepiece optical system is constituted by a plastic refractive optical element 80.

  When the virtual image observation optical device of this example is compared with the eighth example of FIG. 9, the position of the reflection surface of the plastic refractive optical element is different, and the other configurations may be the same.

  The plastic refractive optical element 80 includes a spherical first refractive surface 81, a half mirror 82, an inner concave reflective surface 83, and an aspherical second refractive surface 84. The half mirror 82 is a surface formed inside the plastic refractive optical element 80. The half mirror 82 may be a reflective hologram surface. The reflective surface 83 may be a reflective holographic surface, and is formed as an aspherical surface. A polarizing beam splitter may be provided instead of the half mirror 72, and a quarter wavelength plate may be further provided.

  Light from the illumination light source device 10 passes through the optical film 15 and the polarizer 17, is reflected by the half mirror 21, and reaches the reflective spatial light modulator 20. The light from the reflective spatial light modulator 20 reaches the plastic refractive optical element 80 via the half mirror 21 and the analyzer 26.

  The light reaching the plastic refractive optical element 80 is transmitted through the half mirror 82 via the first refractive surface 81, reflected from the reflective surface 83 and the half mirror 82, and then via the second refractive surface 84. It reaches the pupil 131 of the observation space 130.

  Next, stray light in this example will be described. Part of the light from the illumination light source device 10 passes through the half mirror 21 and the analyzer 26 and reaches the plastic refractive optical element 80. However, in this example, stray light that reaches the plastic refractive optical element 80 does not reach the pupil 131 of the observation space 130.

  In the example shown in FIGS. 9 and 10, the half mirror 21 is a light beam splitting element of the light source optical system, and therefore the angle formed by the half mirror 21 and the reflective spatial light modulator 20 is α. Further, the half mirrors 72 and 82 of the plastic refractive optical elements 70 and 80 are light beam splitting elements of the eyepiece optical system, and the reflecting surfaces 73 and 83 are reflecting elements. Therefore, the angle formed by the surface normal vector A standing on the half mirrors 72 and 82 and the surface normal vector B standing on the reflecting surfaces 73 and 83 of the plastic refractive optical elements 70 and 80 is β.

Examples based on the eighth and ninth examples of the virtual image observation optical apparatus according to the present invention shown in FIGS. 9 and 10 are as follows.
(1) Illumination light source device 10
(A) Light source 11: Light emitting diode (LED)
(B) Optical film 15: Half-value divergence angle HDA≈20 °
(2) Reflective spatial light modulator 20
(A) Liquid crystal: FLC type (b) Display unit: diagonal length DL = 0.55 inch (c) Pixel: VGA 640 × 800
(3) Arrangement of optical system (a) Light beam splitting element of light source optical system = half mirror 21
α ≒ 45 °
(B) Beam splitting element of eyepiece optical system = half mirrors 72 and 82 of plastic refractive optical elements 70 and 80
Reflective element = reflective surfaces 73 and 83 of plastic refractive optical elements 70 and 80
β ≒ 135 °

  FIG. 11 is a ray diagram of a tenth example of the virtual image observation optical apparatus according to the present invention. The configuration of the virtual image observation optical apparatus of this example is the same as that of the sixth example shown in FIG. 7 except that the quarter-wave plate 56 is removed in this example. As shown in the figure, the origin is provided at the point where the exit pupil of the observation space exists, and the z axis is taken along the optical axis, the x axis is taken in the horizontal direction in the plane perpendicular to the optical axis, and the y axis is taken in the vertical direction. As shown in the figure, the positive direction of the z-axis is taken in a direction away from the virtual image observation optical system. The specifications of the optical system of this example are as follows.

Pupil diameter: horizontal diameter 12 mm × vertical diameter 4 mm (calculation of ray aberration and resolution was performed with a pupil diameter of 4 mm)
Eye relief: 20 mm Horizontal field angle: 32 degrees Vertical field angle: 24 degrees Distortion: 5% or less

  As described above, actually, the light from the illumination light source device 10 reaches the exit pupil of the observation space via the light source optical system, the spatial light modulator, and the eyepiece optical system. Here, however, the light path is reversed. follow. Therefore, as shown in the drawing, light from the exit pupil STO in the observation space to the virtual image OBJ is assumed. This light reaches the illumination light source device via the eyepiece optical system, the spatial light modulation element, and the light source optical system.

  In this manner, the surfaces of the optical system existing in the path of the optical path are sequentially numbered. For example, the refractive surface 59 of the glass refractive optical element 50 is given the numeral 3, the polarizing beam splitter 57 is given numerals 4 and 6 for the forward path and the return path, respectively, and the reflective surface 58 is given the numeral 5. Has been. Note that the numeral 10 is assigned to the pixel display surface of the spatial light modulator 20, and 8, 9, 11, and 12 are assigned to the both sides of the polarizer of the spatial light modulator 20 for the forward path and the return path, respectively. Yes.

  Each optical surface is represented by an expression representing the following aspheric surface. RDY on the right side of this equation is a radius of curvature, and K, a, b, c, and d are constants.

[Equation 6]
z = RDY · h ² [1+ (1- (1 + K) RDY ² h ² ) ^1/2 ] ⁻¹ + ah ⁴ + bh ⁶ + ch ⁸ + dh ¹⁰
h ² = x ² + y ²

  FIG. 12 shows data of the optical system of the virtual image observation optical apparatus of this example, and FIG. 13 shows lens data of each optical surface. The data of the optical system in FIG. 12 will be briefly described. The surface number is the number of the surface assigned to each element of the optical system shown in FIG. OBJ is a virtual image position, STO is a pupil, and IMG is a light source device for illumination. Surface numbers 8 to 12 indicate the constituent surfaces of the spatial light modulator. ASP indicates an aspherical surface. REFL indicates a reflective surface, and the absence of REFL indicates a refractive surface.

  The lens data in FIG. 13 will be briefly described. The lens data will be briefly described. A, B, C, D, and K are coefficients in the equation (6), XDE, YDE, and ZDE are eccentricities in the XYZ directions, and ADE, BDE, and CDE are tilts around the XYZ axes. In the table, GLBG1 is a pupil coordinate reference, and IC: Y means that the first surface is targeted when there are a plurality of aspherical curved surfaces.

  14 to 18 are curves showing the light aberration of each surface of the virtual image observation optical apparatus of this example. As shown on the right side of each figure, light aberration was obtained for three wavelengths λ. The vertical axis represents the distance between the position of the principal ray on the image plane and the position of the other rays on the image plane, and the unit is mm. The horizontal axis is the height of light at the entrance pupil, and the maximum value is ± 2 mm. The first parenthesis in the center of each figure is the XY coordinate, and the next parenthesis is the horizontal and vertical angle of view.

  19 to 21 show an MTF (Modulation Transfer function). The vertical axis represents the degree of modulation, and the horizontal axis represents the defocus position. The same three wavelengths were used as in the case of the ray aberration, but synthetic wavelengths with a ratio of 1: 1 to 1: 1 were used for the three wavelengths. The parentheses on the left side of each figure are the horizontal field angle and the vertical field angle.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and it is easily understood by those skilled in the art that other various configurations can be adopted without departing from the gist of the present invention. Let's be done.

  In the above-described example, a liquid crystal spatial light modulator including liquid crystal is used as the reflective spatial light modulator. However, the virtual image observation optical device of the present invention can be used in any type as long as it is a reflection type spatial light modulation element. For example, another reflection type spatial light modulation element such as a digital micromirror device is used. May be.

  In addition, when using a reflective spatial light modulator other than the liquid crystal spatial light modulator in this way, in the light source optical system and the eyepiece optical system, as in the above-described example, a polarizer, an analyzer, and a quarter are used. You may use it combining optical elements, such as phase difference plates, such as a wavelength plate, a micro lens, and a diffuser, suitably.

  In the above-described example, an apparatus including a light source and a light guide plate is used as the illumination light source apparatus, but other illumination light source apparatuses are also possible. For example, a combination of a diffusion plate or fly-eye lens and a laser light source may be used.

  DESCRIPTION OF SYMBOLS 10 ... Illumination light source device, 11 ... Light source, 12 ... Reflector, 13 ... Light guide plate, 13A ... Front surface (output surface), 13B ... Back surface, 14 ... Reflector plate, 15 ... Optical film, 17 ... Polarizer, 20 ... Reflection Type spatial light modulator, 21, 22 ... half mirror, 23 ... reflecting mirror, 25 ... polarizing beam splitter, 26 ... analyzer, 30,30-1 ... total reflection refractive optical element, 30-2 ... refractive optical element, 31 ... refracting surface, 32 ... light splitting surface, 33 ... reflecting surface, 34, 34 ... refracting surface, 40-1 ... refractive optical element, 40-2 ... total reflection refractive optical element, 40-3 ... refractive optical element, 41 ... Refracting surface, 42 ... half mirror, 43, 44, 46 ... refracting surface, 47 ... light splitting surface, 48 ... reflecting surface, 49 ... refracting surface, 50, 50-1, 50-2, 50-3 ... glass refraction Optical element, 50-4 ... Refractive optical element made of glass, 51 ... Folded surface, 52 ... half mirror, 53 ... refracting surface, 56 ... quarter-wave plate, 57 ... polarizing beam splitter, 58 ... reflecting surface, 59 ... refracting surface, 60-1 ... refracting optical element made of glass, 60- DESCRIPTION OF SYMBOLS 2,60-3 ... Plastic refractive optical element, 61, 62 ... Refraction surface, 63 ... Polarization beam splitter, 64 ... Analyzer, 65, 66 ... Refraction surface, 67 ... Half mirror, 68 ... Reflection surface, 70 ... Plastic Refractive optical element, 71 ... refractive surface, 72 ... half mirror, 73 ... reflective surface, 74 ... refractive surface, 80 ... refractive optical element made of plastic, 81 ... refractive surface, 82 ... half mirror, 83 ... reflective surface, 84 ... Refractive surface, 90 ... liquid crystal reflective spatial light modulator, 91A, 91B ... glass substrate, 92A, 92B ... transparent electrode, 93A, 93B ... orientation plate, 94A ... polarizer, 94B ... analyzer, 95 ... liquid crystal material DESCRIPTION OF SYMBOLS 96 ... Reflecting plate, 100 ... FLC type | mold reflective spatial light modulation element, 101A ... Glass substrate, 101B ... Silicon substrate, 102A ... Transparent electrode, 102B ... Aluminum electrode, 103A, 103B ... Orientation film, 104 ... Polarizer, 105 ... Liquid crystal material, 111 ... half mirror, 112 ... analyzer, 130 ... observation space, 131 ... pupil, 200 ... stray light

Claims (17)

A reflective spatial light modulator;
An illumination light source device for providing illumination light to the reflective spatial light modulator;
Is disposed on the optical path of the illumination light rays emitted from the illuminating light source device, having a first beam splitting surface for reflecting the illuminating light from the illuminating light source device leads to the reflective spatial light modulator A light source optical system including a beam splitting element ;
It is arranged on the exit side that has passed through the beam splitting element of the modulated image light beams by the upper Symbol reflection type spatial light modulator, and the refractive surface on the incident side of the image light rays from the reflective spatial light modulator,該屈refracting surface a second beam splitting surface to totally reflect the image light incident from the second reflecting the image light rays totally reflected by the beam splitting surface, by transmitting refracted on SL second beam splitting surface leading to the observation space, free song Menmata comprises a total reflection refractive optical element having a reflecting surface formed Ri by reflection holographic surface,
The normal vector of the reflecting surface at the point where the principal ray passing through the center of the reflective spatial light modulator is reflected by the reflecting surface, and the principal ray passing through the center of the reflective spatial light modulator is the second the angle between the normal vector of the second beam splitting surface at the point that is reflected by the beam splitting surface, a positive vector side light beam at the reflecting surface and the second beam splitting surface of each surface is reflected The direction is 136 degrees or more and 179 degrees or less,
Of the light rays that pass through the optical path from the illumination light source device to the light beam splitting device, the light beam that passes through the light beam splitting device without being reflected by the light beam splitting device is the principal light beam that passes through the center of the reflective spatial light modulator. , as reflected by the incident the reflecting surface from the refracting surface of the total reflection refractive optical element, and the refractive surface of the total reflection refractive optical element, above said beam splitting element above Symbol light source optical system first a first beam splitting surface is arranged,
Of the light rays that pass through the optical path from the illumination light source device to the light beam splitting device, the main light beam that passes through the center of the reflective spatial light modulator is transmitted through the light beam splitting device without being reflected by the light beam splitting device. A virtual image observation optical apparatus configured such that after being reflected by the reflection surface of the total reflection / refraction optical element, an optical path of a light beam directed to the second light beam splitting surface is directed to a region outside the observation space . The virtual image observation optical device according to claim 1, wherein a polarizer is disposed between the illumination light source device and a light beam splitting element of the light source optical system.   The virtual image observation optical apparatus according to claim 1, wherein an analyzer is disposed between the light beam splitting element of the light source optical system and the observation space.   The virtual image observation optical device according to claim 1, wherein the light beam splitting element of the light source optical system is a polarizing light beam splitting element.   4. The virtual image observation optical device according to claim 1, wherein the light beam splitting element of the light source optical system is a non-polarizing light beam splitting element.   The virtual image observation optical device according to claim 1, wherein the light beam splitting element of the light source optical system is a reflective hologram light beam splitting element. The virtual image observation optical apparatus according to claim 1, wherein the second light beam splitting surface of the total reflection / refraction optical element is a polarizing light beam splitting surface. The virtual image observation optical device according to claim 1, wherein the second light beam splitting surface of the total reflection / refraction optical element is a non-polarizing light beam splitting surface. The virtual image observation optical device according to claim 1, wherein the second light beam splitting surface of the total reflection / refractive optical element is a reflective hologram light beam splitting surface. The virtual image observation optical apparatus according to claim 1, wherein a quarter-wave plate is disposed between the second light beam splitting surface of the total catadioptric optical element and the reflecting surface. The virtual image observation optical system according to claim 1, wherein at least one of the second light beam splitting surface, the reflecting surface, and the refracting surface of the total reflection / refractive optical element is a free-form surface having no rotational symmetry axis. apparatus.   The virtual image observation optical device according to claim 1, wherein the illumination light source device includes a light source and a light guide plate.   The virtual image observation optical device according to claim 1, wherein the reflective spatial light modulator is a ferroelectric liquid crystal spatial light modulator. Disposed adjacent to the total reflection refractive optical element has a refractive surface, the light reflected by the reflecting surface of the total reflection refractive optical element via the refracting surface refractive optical element for guiding the said observation space, Furthermore, the virtual image observation optical apparatus in any one of Claims 1-13.   The light source optical system includes a refractive optical element having a free curved surface on at least one of a light incident surface from the illumination light source device and a surface on the reflective spatial light modulation element side. The virtual image observation optical apparatus in any one of -14. Refractive optical element of said light source optical system, the surface of the total reflection refractive optical element side is from the first beam splitting surface having a function of the beam splitting device, said first beam splitting surface the total catadioptric The virtual image observation optical device according to claim 15, wherein the virtual image observation optical device is disposed in contact with the refractive surface of the optical element. The virtual image observation optical device according to any one of claims 1 to 16 , wherein an optical film having a divergence angle control function is disposed between the illumination light source device and a light beam splitting element of the light source optical system.

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