JP4790553B2 - Visual display device - Google Patents

Description

  The present invention relates to a visual display device, and in particular, suitable for an observation device capable of stereoscopic observation from all surrounding directions without using glasses or the like, and a display device capable of displaying different observation images depending on viewing angles and individual persons. The present invention relates to a visual display device.

Conventionally, when a screen provided with a viewing angle limiting filter is rotated around a central axis, for example, an image obtained by viewing one object from a 360 ° peripheral direction is projected on the screen to observe from an arbitrary direction. Patent Documents 1 to 3 are known in which a viewing image changes depending on the viewing direction, and three-dimensional display is possible.
JP 2005-221690 A JP 2006-10852 A JP 2006-11367 A

  However, in the case of the conventional examples known in Patent Documents 1 to 3, a mechanism for mechanically rotating a screen provided with a viewing angle limiting filter is necessary, and observation is performed in that direction when viewed from a specific direction. Possible images can only be seen intermittently. Furthermore, there is a display device that can be viewed stereoscopically with the naked eye without rotating the display element or the screen surface, without using glasses or the like, and capable of observing from any direction around 360 °. There wasn't.

  The present invention has been made in view of such a situation in the prior art, and the object thereof is to enable stereoscopic observation from all directions without using a complicated mechanical rotation mechanism or glasses. And a visual display device suitable for a display device capable of displaying different observation images depending on viewing angles and individual persons.

  In order to solve the above-mentioned problems, the present invention is arranged such that a main optical system that is rotationally symmetric with respect to a central axis is arranged, and a plurality of sub optical systems having the same configuration are arranged in parallel on a circumference that is concentric with the central axis. Further, a third optical system that is rotationally symmetric with respect to the central axis is disposed on the opposite side of each of the sub optical systems across the main optical system, and each of the sub optical systems, the main optical system, and The exit pupil of the combining optical system constituted by the third optical system is opposite to the main optical system side of the third optical system and opposite to the sub optical system corresponding to the central axis. And a display surface is disposed on the opposite side of each sub optical system from the main optical system, and a virtual image of the display surface by each combining optical system is formed in the vicinity of the central axis, and The exit pupil of the combining optical system is formed substantially continuously and concentrically with the central axis, and the display surface is perpendicular to the central axis. It is characterized by being arranged rotationally symmetrical on a straight common plane.

  Further, an intermediate image of the display surface by a combination of each of the sub optical systems and the main optical system is projected in a layered manner in the vicinity of the central axis.

  In addition, the third optical system has a conversion function of converting the angle of view of the superimposed and projected intermediate image in all directions of 360 °, and the intermediate image projected as superimposed is converted to an angle of view. It is characterized by being layered by rotating so as to become the above-mentioned erect virtual image.

  Each of the display surfaces displays a plurality of different videos.

  Further, the plurality of different videos are videos taken from a plurality of viewpoints of the same object.

  In addition, each of the display surfaces is a display surface of a plurality of display elements arranged corresponding to each sub optical system.

  Further, each of the display surfaces is a display surface in which one display element is divided into regions corresponding to each sub optical system.

  Further, at least one surface of the third optical system has a different curvature in a longitudinal section including a rotational symmetry axis and a transverse section orthogonal to the rotational symmetry axis.

When the radius in the direction orthogonal to the central axis of the composite optical system is Rs,
10 <Rs (1)
It satisfies the following condition.

  In addition, at least one surface of the third optical system has a rotationally symmetric shape formed by rotating an arbitrary-shaped curve having no symmetrical surface around a rotational symmetry axis.

  In addition, at least one surface of the third optical system has a rotationally symmetric shape formed by rotating an arbitrarily shaped curve including an odd-order term around a rotationally symmetric axis.

  In the visual display device of the present invention described above, it is possible to observe a stereoscopic image by observing an image with parallax when viewed from the periphery without using a mechanically complicated rotating mechanism or glasses. A visual display device can be provided. Further, it is possible to provide a visual display device that can display different observation images depending on the viewing angle and the viewing direction. Further, since the display surface is formed on a common plane, a virtual image of the display element is formed near the central axis, and a focus mechanism for moving the position of the virtual image can be formed by a linear movement structure. Becomes easier.

  The visual display device of the present invention will be described below based on examples.

  As shown in FIG. 1, the basic principle of the visual display device of the present invention is that a main optical system 2 that is rotationally symmetric is arranged concentrically with a central axis 1 and a plurality of identical configurations are arranged on a circumference concentric with the central axis 1. A sub optical system 3 is arranged in parallel, and a third optical system 4 that is rotationally symmetric with respect to the central axis 1 is arranged on the opposite side of the sub optical system 3 with the main optical system 2 interposed therebetween. 3. The exit pupil 5 of the combining optical system constituted by the main optical system 2 and the third optical system 4 is opposite to the main optical system 2 side of the third optical system 4 and corresponds to the central axis 1. A display surface 16 is disposed on the opposite side of the sub optical system 3 from the main optical system 2 of each sub optical system 3, and a virtual image 8 by each combining optical system is formed near the central axis 1. In addition, the exit pupil 5 of each combining optical system is formed substantially continuously and concentrically with the central axis 1, and the display surface 16 is rotated on a common plane perpendicular to the central axis 1. Those disposed.

  In the case of an optical system that observes the central axis 1 direction from the periphery with respect to the central axis 1, in the conventional optical system in which the image plane is orthogonal to the central axis 1 with a rotational symmetry, it is necessary to bend the light beam greatly. The observed image was greatly distorted, and a relatively large observation area could not be taken.

  On the other hand, in the method of projecting onto the screen disclosed in Patent Documents 1 to 3, it is necessary to rotate the screen.

  Therefore, in the present invention, an optical system that functions as a magnifying optical system from any direction around the central axis is arranged with the rotational symmetry axis (central axis) as the vertical direction, and the observation direction is a horizontal direction substantially perpendicular to the rotational symmetry axis. It is the biggest feature to be able to observe from all directions.

  With such a configuration, it has succeeded in functioning as a magnifying observation optical system (visual display device) from any horizontal direction with the rotational symmetry axis as the vertical direction.

  Hereinafter, description will be given with reference to the drawings. FIG. 10 is a cross-sectional view taken along the central axis of the optical system of the visual display device according to the first embodiment of the present invention, which will be described later, and FIG. 11 is viewed in the direction along the central axis indicating the optical path in the optical system. 12 is an enlarged view of the main part of FIG. 10, and FIG. 13 is an enlarged view of the main part of FIG. 10 and 12, only a part of the sub optical system 3 and the display element 6 are shown.

  Hereinafter, the visual display device of the present invention will be described with reference to FIGS.

  In the optical system of the visual display device of the present invention, a main optical system 2 that is concentric and rotationally symmetric with respect to the central axis 1 is disposed. In this embodiment, the main optical system 2 uses a biconvex lens. However, the main optical system 2 is not limited to a single lens having positive power, and may be a reflection optical system, a catadioptric optical system, or a composite optical system. The requirements are that a positive power is given to the light beam traveling toward the central axis 1 and that it has a rotationally symmetric shape with respect to the central axis 1.

  As is apparent from FIG. 13 in particular, a plurality of sub optical systems 3 having the same configuration are arranged in parallel on a circumference concentric with the central axis 1. The sub optical system 3 is not limited to a single lens, and may be a reflection optical system, a catadioptric optical system, or a composite optical system. Further, on the side opposite to the main optical system 2 of each sub optical system 3, a display surface 16 composed of the display element 6 is arranged on a common plane perpendicular to the central axis 1. Then, an intermediate image 7 of the display element 6 is formed by a combination of each sub optical system 3 and the main optical system 2.

  A third optical system 4 that is concentric and rotationally symmetric with respect to the central axis 1 is disposed on the opposite side of the sub optical system 3 with the main optical system 2 interposed therebetween. The third optical system 4 is not limited to a single refractor, and may be a reflective optical system, a catadioptric optical system, or a composite optical system.

  Further, the exit pupils 5 of the respective synthesis optical systems are arranged concentrically in parallel with the central axis 1. The size of each exit pupil 5 is such that when arranged in parallel, they are connected substantially continuously on the circumference thereof.

  With such a configuration, when the observer brings his / her eyes in the vicinity of any exit pupil 5 position, the sub optical system 3 (sub optical system 3, main optical system 2, and third optical system 4) is sub An intermediate image 7 of the display element 6 is formed near the central axis 1 by the combination of the optical system 3 and the main optical system 2, and a virtual image 8 of the intermediate image 7 is formed near the central axis 1 by the third optical system 4. Can be observed. The composite optical system composed of the sub optical system 3, the main optical system 2, and the third optical system 4 is equivalent to being arranged at fixed angles around the central axis 1, so that the central axis 1 is If the vertical direction is set, the virtual image 8 of the display element 6 on the opposite side across the central axis 1 and the exit pupil 5 where the observer's eyes are located can be observed regardless of the 360 ° direction around the central axis 1. Can be observed.

  In the present invention, since the display surface 16 is arranged on a common plane perpendicular to the central axis 1, the virtual image 8 of the display element 6 is formed in the vicinity of the central axis 1, and the focus mechanism moves the position of the virtual image 8. Can be formed in a linearly moving structure, and the display element can be easily assembled.

  Furthermore, a plurality of identical sub optical systems 3 are arranged concentrically and in parallel, and the exit pupil 5 is arranged substantially continuously and concentrically with the central axis 1, whereby a wide observation region can be formed. A wide observation area can be secured without using a diffusion plate or the like by the exit pupils 5 projected in parallel continuously. Further, the image of the display element 6 is enlarged and projected as an intermediate image 7 near the central axis 1 by the combination of the sub optical system 3 and the main optical system 2. The observer observes the projected intermediate image 7 through the third optical system 4 and can observe the large virtual image 8.

  Further, if the virtual image 8 is arranged in the vicinity of the central axis 1, at least the convergence of the virtual image 8 projected by the synthesis optical system can coincide with the convergence point of both eyes, and a stereoscopic display that is easy to fuse is obtained. It becomes possible.

  More preferably, it is desirable that each display element 6 displays images taken from a plurality of viewpoints for the same object. That is, as shown in FIG. 2, the parallax image of the object 100 is a still image captured by the camera 101 by rotating the object 100 every 22.5 ° when the entire circumference of 360 ° is divided into 16, for example. Alternatively, a moving image generated by rotating a viewpoint every 22.5 ° similarly for a three-dimensional object created by CG or the like may be used. Furthermore, it may be a moving image from an imaging device in which 16 cameras are installed toward the center point.

  The still images and moving images with 16 viewpoints created in this way become 16 viewpoint videos as shown in FIG. 3 with 16 images of the object 100 arranged side by side. Such an image is displayed on the entire display surface 16 formed by arranging the individual display elements 6 so as to be concentric in the order of the photographed angles as shown in FIG.

  When such parallax images are arranged on the respective display elements 6 in the order of angles taken around the central axis, as shown in FIG. 5, when the left and right eyeballs EL and ER of the observer are positioned on the adjacent exit pupil 5 The virtual image 8 of the binocular parallax image is seen in the left and right eyeballs EL and ER, and the stereoscopic image of the photographed object 100 is seen.

  Here, as for the position of the exit pupil 5 and the left and right eyeballs EL and ER of the observer at the observation position, as shown in FIG. 6, at least the standard of the eye width is 65 mm. Desirably, the projected exit pupils 5 of the system 50 are also 65 mm apart. Further, the shape of the exit pupil 5 is not limited to a square as shown in FIG. 5, but may be an ellipse or a rectangle.

  Also, as shown in FIG. 6, when the observation position is a clear vision distance of 30 cm, the standard eye width is 65 mm. Therefore, the observation region by one synthetic optical system of the optical system 50 of the visual display device of the present invention is 12 It is preferably 37 ° or more. Furthermore, when the observer E moves his / her head, as shown in FIG. 7, the observer sequentially moves to the observation area by the adjacent synthetic optical system and eventually observes a stereoscopic image from all directions of 360 °. It becomes possible. It is also possible to observe the omnidirectional stereoscopic image by mechanically rotating the optical system 50, or to electronically switch the display image of each display element 6 to observe the stereoscopic image from all directions. It is also possible to do so.

  Note that the image to be arranged on each display element 6 is not limited to an image in which the parallax images as described above are arranged in the order of angles. For example, by making a completely different image with a certain angle as a boundary, the viewing angle or individual Therefore, different images can be observed.

  The exit pupils 5 are preferably arranged continuously. However, the present invention is not limited to this, and as shown in FIG. 8, even if the exit pupils 5 are slightly separated, the parallax image is rotated around the central axis. When arranged on each exit pupil 5 in the order of the captured angles, when the left and right eyeballs EL and ER of the observer are positioned on the adjacent exit pupil 5, the virtual image 8 of the binocular parallax image can be seen on the left and right eyeballs EL and ER. It is the same that the stereoscopic image of the photographed object 100 can be seen.

  An image showing the positional relationship between the third optical system 4 and the virtual image 8 of the visual display device of the present invention is shown in the schematic diagram of FIG.

  Further, preferably, the intermediate image 7 of the display surface 16 by the combination of the sub optical system 3 and the main optical system 2 is projected in a layered manner in the vicinity of the central axis 1, thereby comparing with the outer diameter of the visual display device A large virtual image can be displayed.

  More preferably, the third optical system 4 has a conversion action of converting the angle of view of the superimposed and projected virtual image in all directions of 360 °, and the superimposed and projected virtual image is erected after the angle of view conversion. Since they are rotated and layered so as to form a virtual image, it is possible to observe from the entire circumference at an arbitrary angle with respect to the rotational symmetry axis by the view angle conversion action.

  Further, since a plurality of different images are displayed on each display surface 16, different images can be displayed depending on the viewing angle even in the same region.

  Preferably, the plurality of different images are images taken from a plurality of viewpoints of the same object, so that stereoscopic observation can be performed.

  More preferably, each display surface 16 is a display surface 16 of a plurality of display elements 6 arranged corresponding to each sub-optical system 3, so that a general-purpose plane can be obtained without newly manufacturing a special display element 6. By dividing the display surface 16 by the display element 6, each display element 6 can be configured, and the apparatus can be configured at low cost.

Further, since each display surface 16 is a display surface 16 corresponding to each sub optical system 3 and one display element 6 is divided into each region, the display surface 16 can be formed by one display element 6. It is possible to configure with a simple structure.

Further, it is desirable that at least one surface of the third optical system 4 is configured to have different curvatures in a longitudinal section including the rotational symmetry axis (center axis) 1 and a transverse section orthogonal to the rotational symmetry axis 1. . In the optical system of the present invention, a plurality of sub optical systems 3 are arranged in parallel on a circumference concentric with the central axis 1. Therefore, the sub optical system 3 is decentered with respect to the main optical system 2, and decentration aberration occurs. In order to reduce this, at least one surface of the third optical system 4 is configured to have different curvatures in a longitudinal section including the rotational symmetry axis (center axis) 1 and a transverse section orthogonal to the rotational symmetry axis 1. This makes it possible to correct this decentration aberration.

  Preferably, when the radius in the direction orthogonal to the central axis 1 of the combining optical system is Rs, it is desirable to satisfy the condition of 10 <Rs. If the lower limit is exceeded, the observation image becomes small, and it becomes difficult to make a realistic observation.

  More preferably, at least one surface of the third optical system 4 is further decentered by having a rotationally symmetric shape formed by rotating an arbitrary-shaped curve having no symmetric surface around the rotational symmetry axis 1. It becomes possible to correct aberration, for example, coma generated by decentration.

  More preferably, at least one surface of the third optical system 4 has a rotationally symmetric shape formed by rotating an arbitrarily shaped curve including an odd-order term around the rotational symmetry axis 1, thereby further increasing the degree of freedom. Aberration correction can be performed, which is preferable in terms of aberration correction.

  In addition, Rs of the optical system of Example 1 and Example 2 demonstrated below is as follows. Here, Rs indicates a radius in a direction orthogonal to the central axis of the optical system.

Example 1
Rs (mm) 32.00
Example 2
Rs (mm) 30.00
Rs is
10 <Rs (1)
It is desirable to satisfy the following conditions. More preferably,
20 <Rs (1-1)
It is desirable to satisfy the following conditions. If the lower limit is exceeded, the observation image becomes small, and it becomes difficult to make a realistic observation.

  By the way, in the visual display device of the present invention, the display elements 6 are arranged corresponding to the sub optical systems 3 respectively, but the entire display surface 16 in which the display elements 6 are arranged in parallel is a plane as described above. It becomes a shape. This may be constituted by a single display element 6, or a plurality of flat display elements 6 may be arranged rotationally symmetrically.

  Examples 1 and 2 of the optical system of the visual display device of the present invention will be described below. The configuration parameters of these optical systems will be described later. For example, as shown in FIG. 12 and FIG. 13, the configuration parameters of these embodiments are such that the surface where the virtual image 8 can be formed is the object plane 8, the plane conjugate with the virtual image 8 is the image plane 6 which is the display plane 6, and the exit pupil. 5 through the optical surface 41 and 42 of the third optical system 4, the optical surfaces 21 and 22 of the main optical system 2, and the optical surfaces 31 and 32 of the sub optical system 3 in this order. This is based on the results of back ray tracing to the display element 6 and the display surface 16.

  For example, as shown in FIG. 12, the coordinate system uses the center of the object plane 8 (located on the central axis 1) as the origin of the decentered optical surface of the decentered optical system, and the display element 6 of the center axis 1 is used. The direction opposite to the Y axis is the Y axis positive direction, and the inside of FIG. 12 is the YZ plane. Then, the direction of the display element 6 on the right side of FIG. 12 is the Z-axis positive direction, and the Y-axis, the Z-axis and the axis constituting the right-handed orthogonal coordinate system are the X-axis positive direction.

  For the decentered surface, the amount of decentering from the center of the origin of the optical system in the coordinate system in which the surface is defined (X-axis direction, Y-axis direction, and Z-axis direction are X, Y, and Z, respectively) and the optical system The inclination angles (α, β, γ (°), respectively) of the coordinate system defining each surface centered on the X axis, Y axis, and Z axis of the coordinate system defined at the origin are given. In this case, positive α and β mean counterclockwise rotation with respect to the positive direction of each axis, and positive γ means clockwise rotation with respect to the positive direction of the Z axis. Note that the α, β, and γ rotations of the central axis of the surface are performed by rotating the coordinate system defining each surface counterclockwise around the X axis of the coordinate system defined at the origin of the optical system. Then rotate it around the Y axis of the new rotated coordinate system by β and then rotate it around the Z axis of another rotated new coordinate system by γ. It is.

  Further, among the optical action surfaces constituting the optical system of each embodiment, when a specific surface and a subsequent surface constitute a coaxial optical system, a surface interval is given, in addition, the curvature radius of the surface, The refractive index and Abbe number of the medium are given according to conventional methods. In addition, the surface after the 6th surface of Example 1 and the surface after the 10th surface of Example 2 are translated with respect to the central axis 1 by a value defined by each eccentricity (6).

  The extended rotation free-form surface is a rotationally symmetric surface given by the following definition.

  First, the following curve (d) passing through the origin on the YZ coordinate plane is determined.

^{Z = (Y 2 / RY)} / [1+ {1- (C 1 +1) Y 2 / RY 2} 1/2]
+ C ₂ Y + C ₃ Y ² + C ₄ Y ³ + C ₅ Y ⁴ + C ₆ Y ⁵ + C ₇ Y ⁶
+ ··· + C ₂₁ Y ²⁰ + ··· + C _{n + 1} Y ⁿ + ···
... (d)
Next, a curve F (Y) obtained by rotating the curve (d) in the positive direction of the X axis and rotating counterclockwise to the positive angle θ (°) is determined. This curve F (Y) also passes through the origin on the YZ coordinate plane.

  The curve F (Y) is translated in the positive Z direction by a distance R (or negative Z direction if negative), and then the rotationally symmetric surface formed by rotating the translated curve around the Y axis is expanded and rotated. Let it be a free-form surface.

  As a result, the extended rotation free-form surface becomes a free-form surface (free-form curve) in the YZ plane and a circle with a radius | R | in the XZ plane.

  From this definition, the Y-axis becomes the axis of the extended rotation free-form surface (rotation symmetry axis).

Where RY is the radius of curvature of the spherical term in the YZ section, C ₁ is the conic constant, C ₂ , C ₃ , C ₄ , C ₅ . Aspheric coefficient.

A conical surface having an axis parallel to the Y axis as a central axis is given as one of the extended rotation free-form surfaces, and RY = ∞, C ₁ , C ₂ , C ₃ , C ₄ , C ₅ ,. , Θ = (conical surface inclination angle), R = (radius of bottom surface in XZ plane).

  In addition, a term relating to an aspheric surface for which no data is described in the constituent parameters described later is zero. The refractive index and the Abbe number are shown for the d-line (wavelength 587.56 nm). The unit of length is mm. As described above, the eccentricity of each surface is expressed by the amount of eccentricity from the reference surface.

  FIG. 10 is a cross-sectional view taken along the central axis 1 of the optical system of the visual display device of Example 1, and FIG. 11 is a plan view seen in the direction along the central axis 1 showing the optical path in the optical system. An enlarged view of the main part of FIG. 10 is shown in FIG. 12, and an enlarged view of the main part of FIG. 11 is shown in FIG. However, the main optical system is not shown for the sake of simplicity. 10 and 12, only a part of the sub optical system 3 and the display element 6 are shown. Further, FIG. 14 shows a lateral aberration diagram of the entire optical system of this example. In this lateral aberration diagram, the angle shown at the center indicates (horizontal field angle, vertical field angle), and the lateral aberrations in the Y direction (meridional direction) and X direction (sagittal direction) at that field angle. Show. Note that a negative field angle means a clockwise angle in the Y-axis positive direction for the horizontal field angle, and a clockwise angle in the X-axis positive direction for the vertical field angle. same as below.

  In the first embodiment, a main optical system 2 that is concentric and rotationally symmetric with respect to the central axis 1 is disposed. In this embodiment, the main optical system 2 uses a biconvex lens. However, the main optical system 2 is not limited to a single lens having positive power, and may be a reflection optical system, a catadioptric optical system, or a composite optical system. The requirements are that a positive power is given to the light beam traveling toward the central axis 1 and that it has a rotationally symmetric shape with respect to the central axis 1.

  As is apparent from FIG. 13 in particular, a plurality of sub optical systems 3 having the same configuration are arranged in parallel on a circumference concentric with the central axis 1. Each of the sub optical systems 3 is not limited to a single lens, and may be a reflection optical system, a catadioptric optical system, or a composite optical system.

  Further, on the side opposite to the main optical system 2 of each sub optical system 3, a display surface 16 composed of the display element 6 is arranged on a common plane perpendicular to the central axis 1. Then, the intermediate image 7 of the display element 6 is projected in the vicinity of the central axis 1 by the combination of the sub optical system 3 and the main optical system 2.

  A third optical system 4 that is concentric and rotationally symmetric with respect to the central axis 1 is disposed on the opposite side of the sub optical system 3 with the main optical system 2 interposed therebetween. The third optical system 4 is not limited to a single refractor, and may be a reflective optical system, a catadioptric optical system, or a composite optical system.

  Further, the exit pupils 5 of the respective synthesis optical systems are arranged concentrically in parallel with the central axis 1. The size of each exit pupil 5 is such that when arranged in parallel, they are connected substantially continuously on the circumference thereof.

  With such a configuration, when the observer brings his / her eyes in the vicinity of any exit pupil 5 position, the sub optical system 3 (sub optical system 3, main optical system 2, and third optical system 4) is sub By combining the optical system 3 and the main optical system 2, the intermediate image 7 of the display element 6 is projected in the vicinity of the central axis 1, and each intermediate image 7 is directed by the third optical system 4 toward 360 ° in all directions. The angle of view is converted, and it can be formed and observed as a virtual image upright after the angle of view conversion in the vicinity of the central axis 1. The composite optical system composed of the sub optical system 3, the main optical system 2, and the third optical system 4 is equivalent to being arranged at fixed angles around the central axis 1, so that the central axis 1 is If the vertical direction is set, the virtual image 8 of the display element 6 on the opposite side across the central axis 1 and the exit pupil 5 where the observer's eyes are located can be observed regardless of the 360 ° direction around the central axis 1. Can be observed.

  In this embodiment, the display surface 16 is a large plane, which may be composed of one display element 6, but 22 plane display elements 6 are arranged in parallel in a rotationally symmetrical manner. May be.

The specification of this Example 1 is
Exit pupil diameter 60mm
Display size X4.67mm x Y6.03mm
Image size □ 10mm × 10mm
It is.

  Next, FIG. 15 is a cross-sectional view taken along the central axis 1 of the main part of the optical system of the visual display device of Modification 1 in which the display element 6 of Embodiment 1 is arranged on a cylinder. FIG. 16 is a plan view seen in the direction along the central axis 1 showing the optical path in the optical system of the part. However, the main optical system is not shown for the sake of simplicity. FIG. 17 shows an image of the display surface and the display element 6 arranged on the cylinder. In FIGS. 15 and 16, only a part of the sub optical system 3 and the display element 6 are shown, and the exit pupil 5 (FIG. 13) is omitted, so that it is not shown. Further, the lateral aberration diagram of the entire optical system of Modification 1 is omitted.

  In the first modification, a main optical system 2 that is concentric and rotationally symmetric with respect to the central axis 1 is disposed. In this embodiment, the main optical system 2 uses a biconvex lens. However, the main optical system 2 is not limited to a single lens having positive power, and may be a reflection optical system, a catadioptric optical system, or a composite optical system. The requirements are that a positive power is given to the light beam traveling toward the central axis 1 and that it has a rotationally symmetric shape with respect to the central axis 1.

  In the first modification, as shown in FIG. 17, the display element 6 is arranged in a cylindrical shape to form a display surface 16, and 22 biconvex lenses 3a concentric with the central axis are arranged in a cylindrical shape in parallel inside the display element 6. A plane mirror 3b is disposed between the biconvex lens 3a and the main optical system 2, and the sub-optical system 3 is formed by the biconvex lens 3a and each plane mirror 3b. Accordingly, the plane mirror 3b is disposed on a twenty-two pyramid surface concentric with the central axis 1 and having an apex angle of 90 °. Then, the intermediate image 7 of the display element 6 is projected in the vicinity of the central axis 1 by the combination of the sub optical system 3 and the main optical system 2.

  A third optical system 4 that is concentric and rotationally symmetric with respect to the central axis 1 is disposed on the opposite side of the sub optical system 3 with the main optical system 2 interposed therebetween. The third optical system 4 is not limited to a single refractor, and may be a reflective optical system, a catadioptric optical system, or a composite optical system.

  Further, the exit pupils 5 of the respective synthesis optical systems are arranged concentrically in parallel with the central axis 1. The size of each exit pupil 5 is such that when arranged in parallel, they are connected substantially continuously on the circumference thereof.

  With such a configuration, when the observer brings his / her eyes in the vicinity of any exit pupil 5 position, the sub optical system 3 (sub optical system 3, main optical system 2, and third optical system 4) is sub By combining the optical system 3 and the main optical system 2, the intermediate image 7 of the display element 6 is projected in the vicinity of the central axis 1, and each intermediate image 7 is directed by the third optical system 4 toward 360 ° in all directions. The angle of view is converted, and it can be formed and observed as a virtual image upright after the angle of view conversion in the vicinity of the central axis 1. The composite optical system composed of the sub optical system 3, the main optical system 2, and the third optical system 4 is equivalent to being arranged at fixed angles around the central axis 1, so that the central axis 1 is If the vertical direction is set, the virtual image 8 of the display element 6 on the opposite side across the central axis 1 and the exit pupil 5 where the observer's eyes are located can be observed regardless of the 360 ° direction around the central axis 1. Can be observed.

  In this modification, the display surface 16 is an inner surface of a cylindrical surface, which may be constituted by one display element 6, but 22 flat display elements 6 are provided on each side of the twenty-two prisms. You may comprise by arrange | positioning rotationally symmetrically.

  Next, FIG. 18 is a cross-sectional view taken along the central axis 1 of the main part of the optical system of the visual display device of Example 2, and in the direction along the central axis 1 showing the optical path in the optical system of the main part. A plan view is shown in FIG. However, the main optical system is not shown for the sake of simplicity. Since the exit pupil 5 is out of the box, the illustration is omitted. A lateral aberration diagram of the entire optical system of this example is shown in FIG.

This embodiment is an example in which the main optical system 2 is configured in the order of reverse tracking in the order of a biconcave negative lens 2L ₁ , a biconvex positive lens 2L ₂ and a biconvex positive lens 2L ₃ concentric with the central axis 1. The light rays are refracted by each lens and go out of the main optical system 2. Then, 30 sub optical systems 3 having the same configuration are arranged in parallel on a circumference concentric with the central axis 1 so as to face the biconvex positive lens 2L ₃ of the main optical system 2.

The sub optical system 3 includes a lens group that is eccentric with respect to the central axis, and is arranged in parallel on a circumference concentric with the central axis 1. Each sub optical system 3 includes, in order of reverse tracking, a cemented lens of a negative meniscus lens 3L ₁ and a biconvex positive lens 3L ₂ with a concave surface facing the display element 6 side, and a biconvex positive lens 3L ₂ and a display element 6 It consists of a cemented lens with a negative meniscus lens 3L ₄ with a convex surface facing the side.

  Further, on the side opposite to the main optical system 2 of each sub optical system 3, a display surface 16 composed of the display element 6 is arranged on a common plane perpendicular to the central axis 1. Then, the intermediate image 7 of the display element 6 is projected in a layered manner by the combination of each sub optical system 3 and the main optical system 2.

  The third optical system 4 is a refracting body having a substantially triangular prism shape in cross section having a first free curved surface 41 and a second free curved surface 42 arranged concentrically and symmetrically with respect to the central axis 1.

  Further, the exit pupils 5 of the respective synthesis optical systems are arranged concentrically in parallel with the central axis 1. The size of each exit pupil 5 is such that when arranged in parallel, they are connected substantially continuously on the circumference thereof.

  With such a configuration, when the observer brings his / her eyes in the vicinity of any exit pupil 5 position, the sub optical system 3 (sub optical system 3, main optical system 2, and third optical system 4) is sub By combining the optical system 3 and the main optical system 2, the intermediate image 7 of the display element 6 is projected in the vicinity of the central axis 1, and each intermediate image 7 is directed by the third optical system 4 toward 360 ° in all directions. The angle of view is converted, and it can be formed and observed as a virtual image upright after the angle of view conversion in the vicinity of the central axis 1. The composite optical system composed of the sub optical system 3, the main optical system 2, and the third optical system 4 is equivalent to being arranged at fixed angles around the central axis 1, so that the central axis 1 is If the vertical direction is set, the virtual image 8 of the display element 6 on the opposite side across the central axis 1 and the exit pupil 5 where the observer's eyes are located can be observed regardless of the 360 ° direction around the central axis 1. Can be observed.

  In this embodiment, the display surface 16 is a large plane, which may be composed of one display element 6, but 22 plane display elements 6 are arranged in parallel in a rotationally symmetrical manner. May be.

The specification of Example 2 is
Exit pupil diameter 60mm
Display size X 3.87mm x Y 6.42mm
Image size □ 10mm × 10mm
The configuration parameters of Example 1 and Example 2 are shown below. In the table below, “ERFS” indicates an extended rotation free-form surface.
Example 1
Surface number Curvature radius Surface spacing Eccentricity Refractive index Abbe number Object surface ∞ (1)
1 ∞ (Pupil) (2)
2 ERFS [1] (3) 1.5163 64.1
3 ERFS [2] (4)
4 389.66 10.00 (5) 1.8830 40.7
5 -35.83 46.63
6 18.78 3.00 (6) 1.8830 40.7
7 -22.90 11.94
Image plane ∞
ERFS [1]
RY 38.05
θ -65.32
R -24.59
C ₄ -1.6653 × 10 ^-4
ERFS [2]
RY 19.37
θ -33.64
R -20.99
C ₄ -2.7966 × 10 ^-4
Eccentric [1]
X 0.00 Y 0.00 Z 0.00
α -45.00 β 0.00 γ 0.00
Eccentric [2]
X 0.00 Y 212.13 Z -212.13
α -45.00 β 0.00 γ 0.00
Eccentric [3]
X 0.00 Y 24.59 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric [4]
X 0.00 Y 19.97 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric [5]
X 0.00 Y -33.30 Z 0.00
α -90.00 β 0.00 γ 0.00
Eccentric [6]
X 0.00 Y 0.00 Z 18.04
α 0.00 β 0.00 γ 0.00
Example 2
Surface number Curvature radius Surface spacing Eccentricity Refractive index Abbe number Object surface ∞ (1)
1 ∞ (Pupil) (2)
2 ERFS [1] (3) 1.5163 64.1
3 ERFS [2] (4)
4 -117.07 3.00 (5) 1.4940 66.6
5 22.21 1.00
6 24.43 9.35 1.4875 70.4
7 -31.78 1.00
8 69.27 5.73 1.4875 70.4
9 -35.93 44.68
10 23.63 1.00 (6) 1.7552 27.6
11 8.93 8.21 1.6099 55.9
12 -14.09 1.00
13 12.69 9.52 1.7518 31.2
14 -10.00 1.00 1.7493 27.8
15 -84.18 3.00
Image plane ∞
ERFS [1]
RY 37.29
θ -73.29
R -21.29
C ₄ 2.8026 × 10 ^-13
ERFS [2]
RY -18.22
θ -20.57
R-14.31
C ₄ 4.1927 × 10 ^-13
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α -28.89 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 150.00 Z -259.81
α -30.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 12.29 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 4.95 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y -14.12 Z 0.00
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 0.00 Z 18.75
α 0.00 β 0.00 γ 0.00
FIG. 21A shows a rotationally symmetric prism surface about the central axis 1 instead of the rotationally symmetric prism body 40 as an example of the third optical system 4 of the first embodiment shown in FIGS. It is a figure which shows the modification of Example 1 which used the rotation symmetry Fresnel prism body 45 made into the Fresnel prism surface, and made the observation direction the substantially horizontal direction. The cross-sectional shape including the central axis 1 of the rotationally symmetric Fresnel prism body 45 is as shown in FIG. However, FIG.21 (b) is an expanded sectional view of the A section of Fig.21 (a).

  By using the rotationally symmetric Fresnel prism body 45 as described above in the optical system of the visual display device of the present invention, it is possible to make the optical element to be added thinner, which is preferable for weight reduction.

  FIG. 22 shows a state in which a diffusion plate 25 that is rotationally symmetric with respect to the central axis 1 is arranged on the image plane of the intermediate image 7. FIG. 23A is a perspective view of the diffusion plate 25, and FIG. 23B is a cross-sectional view of the diffusion plate 25. For the diffusion plate 25, it is important to apply a rotationally symmetric lenticular sheet or the like that diffuses only in the radial direction, and to control the diffusion angle so that the projected images do not cause crosstalk. As described above, by reducing the pupil of the sub optical system 3 and enlarging the pupil with the diffusion plate 25, it is possible to reduce the burden on the aberration correction of the sub optical system 3.

  In the optical system as described above of the visual display device of the present invention, the optical system (main optical system 2 + sub optical system 3 + third optical system 4) that is rotationally symmetric about the central axis 1 is used as it is. The virtual image 8 of the display element 6 on the display surface (display element) 16 can be observed from all directions of 360 ° around the system, but the optical system is cut by a cross section including the central axis 1 and halved. Of course, the virtual image 8 may be observed in an angular range of 180 °, 120 °, 240 °, etc. around the central axis 1 by setting it to 1/3, 2/3, or the like.

It is a figure which shows the basic principle of this invention. It is a figure for demonstrating the imaging | photography method of the parallax image arrange | positioned on the display surface of the optical system of the visual display apparatus of this invention. It is a figure which shows the example of the parallax image image | photographed with the imaging | photography method of FIG. It is a figure which shows how to display the parallax image on the whole display surface on a common plane. It is a figure which shows a mode that an observer's right and left eyeball is located in the exit pupil which the optical system of the visual display apparatus of this invention adjoins. It is a figure which shows the eye width of an eyeball of an observer's right and left, and the space | interval of the adjacent exit pupil of the optical system of the visual display apparatus of this invention. It is a figure which shows a mode that it moves to the observation area | region by an adjacent synthetic | combination optical system sequentially, when an observer moves a head. FIG. 6 is a diagram corresponding to FIG. 5 when each display element is slightly separated. It is a schematic diagram which shows the image of the virtual image of the visual display apparatus of this invention. It is sectional drawing taken along the central axis of the optical system of the visual display apparatus of Example 1 of this invention. It is the top view seen in the direction in alignment with the central axis which shows the optical path in the optical system of FIG. It is an enlarged view of the principal part of FIG. It is an enlarged view of the principal part of FIG. 2 is a transverse aberration diagram for the whole optical system of Example 1. FIG. It is sectional drawing taken along the central axis of the principal part of the optical system of the visual display apparatus of the modification 1. It is the top view seen in the direction in alignment with the central axis which shows the optical path in the optical system of the principal part of FIG. It is a figure which shows how to display the parallax image on the cylindrical whole display surface as a modification. It is sectional drawing taken along the central axis of the principal part of the optical system of the visual display apparatus of Example 2 of this invention. It is the top view seen in the direction in alignment with the central axis which shows the optical path in the optical system of the principal part of FIG. FIG. 6 is a transverse aberration diagram for the whole optical system of Example 2. It is a figure corresponding to FIG. 12 of the Example which uses a rotationally symmetric Fresnel prism body as a 3rd optical system. It is a figure corresponding to FIG. 12 of the Example which uses a diffuser plate. It is a figure which shows the structure of a diffusion plate.

Explanation of symbols

1 ... central axis 2 ... main optical system 21, 22 ... main optical system of the optical surfaces 2L ₁ ... biconcave negative lens 2L ₂ ... biconvex positive lens 2L ₃ ... biconvex positive lens 25 ... diffusing plate 3 ... secondary optical system 31 , display negative meniscus lens 3L ₂ ... biconvex positive lens 3L ₃ ... biconvex positive lens 3L ₄ ... convex surface directed toward the optical surfaces 3a ... biconvex lens 3b ... plane mirror 3L ₁ ... concave 32 ... secondary optical system on the display surface side Negative meniscus lens 4 directed to the surface side ... Third optical system 40 ... Rotationally symmetric prism body 41 ... First free-form surface 42 ... Second free-form surface 45 ... Rotation-symmetric Fresnel prism body 5 ... Exit pupil 6 ... Display element (image surface) )
16 ... Display surface 7 ... Intermediate image 8 ... Virtual image (object surface)
50. Optical system of visual display device (present invention)
100 ... object 101 ... camera EL, ER ... eyeball E ... observer

Claims (11)

  A main optical system that is rotationally symmetric with respect to the central axis is disposed, and a plurality of sub-optical systems having the same configuration are disposed in parallel on a circumference that is concentric with the central axis. A third optical system that is rotationally symmetric with respect to the central axis is disposed on the opposite side of each of the sub optical systems, and is a combined optical system that includes the sub optical system, the main optical system, and the third optical system. Is located on the opposite side of the third optical system from the main optical system side and on the opposite side to the sub optical system corresponding to the central axis. A display surface is disposed on the opposite side of the optical system, a virtual image of the display surface by each of the combining optical systems is formed in the vicinity of the central axis, and the exit pupil of each of the combining optical systems is on the central axis Concentric and substantially continuous, the display surface is rotationally symmetrical on a common plane perpendicular to the central axis. A visual display device characterized by that.   The visual display device according to claim 1, wherein an intermediate image of the display surface by a combination of each of the sub optical systems and the main optical system is projected in a layered manner in the vicinity of the central axis.   The third optical system has a converting function of converting the angle of view of the intermediate and projected intermediate image toward 360 ° in all directions, and each of the intermediate images to be projected after being overlapped is subjected to angle-of-view conversion. 3. The visual display device according to claim 2, wherein the visual display device is rotated and overlaid so as to become the upright virtual image.   The visual display device according to claim 1, wherein each of the display surfaces displays a plurality of different images.   The visual display device according to claim 4, wherein the plurality of different images are images taken from a plurality of viewpoints of the same object.   6. The visual display device according to claim 1, wherein each of the display surfaces is a display surface of a plurality of display elements arranged corresponding to each sub optical system.   6. The visual display device according to claim 1, wherein each of the display surfaces is a display surface in which one display element is divided into regions corresponding to each sub optical system.   8. The curvature according to claim 1, wherein at least one surface of the third optical system has different curvatures in a longitudinal section including a rotational symmetry axis and a transverse section perpendicular to the rotational symmetry axis. Visual display device. When the radius in the direction orthogonal to the central axis of the synthetic optical system is Rs,
10 <Rs (1)
The visual display device according to claim 1, wherein the following condition is satisfied.   The at least one surface of the third optical system has a rotationally symmetric shape formed by rotating an arbitrary-shaped curve having no symmetric surface around a rotational symmetry axis. Item 9. The visual display device according to any one of Items 8 to 8.   The at least one surface of the third optical system has a rotationally symmetric shape formed by rotating an arbitrarily shaped curve including an odd-order term around a rotational symmetry axis. The visual display device according to any one of 10.

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