JP2012173736A - Stereoscopic display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems that, while video light of linear polarization is viewed through a half mirror for which reflectance and transmissivity are respectively equal, the half mirror of such a characteristic is expensive, the transmissivity is low and the characteristic of the linear polarization is destroyed in the case of using an inexpensive one, and it is difficult to accurately arrange an angle and a distance formed by two image display devices for a left eye and for a right eye.SOLUTION: A transparent plate produced with a resin, a glass or the like is used instead of a half mirror and transmission light is increased. For reflected light, two image display devices are installed so as to form an angle larger than 90 degrees and close to 180 degrees to increase an incident angle from the image display devices to the transparent plate, and by turning a polarization direction of the light of images reflected on the transparent plate to a direction vertical to the incidence plane to the transparent plate, the reflectance is increased and a sufficient light quantity is obtained. Also, in order to facilitate assembly, the two image display devices are integrated.

Description

The present invention relates to a stereoscopic display device using the parallax between human eyes.

Conventionally, the thing of patent document 1 is disclosed as a three-dimensional display apparatus using parallax of human eyes.
The stereoscopic display device described in Patent Document 1 will be described with reference to FIG.

FIG. 2 is a block diagram showing a conventional stereoscopic display device as a whole. Reference numeral 4 denotes a square half mirror having the same transmittance and reflectance, and the upper end of the half mirror 4 is in front of the upper part of the observation window 6. While fixing, the lower end part of the said half mirror 4 is fixed to the back lower part of the said observation window 4, and the said half mirror 4 forms a 45 degree surface toward a front surface direction with respect to a horizontal surface.

The left-eye image display device 1L for displaying the left-eye screen is arranged behind the half mirror 4 on the side opposite to the observation window 6 so that the screen is vertical, and the polarization direction thereof is horizontal. To. In this case, the upper side of the left-eye image display device 1L corresponds to the upper side of the observation window 6, and the lower side of the left-eye image display device 1L corresponds to the lower side of the observation window 6.

The right-eye image display device 1R for displaying the right-eye screen is fixed horizontally below the half mirror 4, and the polarization direction of the right-eye image display device 1R is the same as the polarization direction of the left-eye image display device 1L. The direction is parallel to the line of intersection between the plane and the plane of the half mirror 4. At this time, the upper side of the screen of the image display device 1R is positioned on the near side, and the lower side of the screen of the image display device 1R for the right eye is positioned on the back side.

A half-wave plate 2 is attached to the video display surface of the right-eye image display device 1R. The half-wave plate 2 can rotate the polarization plane of incident light, and rotates the polarization direction of the right-eye image display device 1R by 90 degrees within the plane.

Obtained by reflecting the half-mirror 4 of the image obtained from the right-eye image display device 1R by arranging the half-wave plate 2 on the screen of the right-eye image display device 1R and further arranging the polarizer 3. The polarization direction of the obtained image is the vertical direction, and the polarization direction of the image obtained by transmitting through the half mirror 4 of the image obtained from the left-eye image display device 1L is the horizontal direction. The polarized light obtained in this way is in the vertical and horizontal directions, and a good stereoscopic image can be obtained without losing the characteristics of linearly polarized light.

Reference numeral 5 denotes polarizing glasses worn by an observer, 5L and 5R are left-eye and right-eye analyzers, the left-eye analyzer 5L has a horizontal polarization angle, and the right-eye analyzer 5R is vertical polarization. Have an angle. Here, when an observer observes from the observation window 6 with the left-eye analyzer 5L and the right-eye analyzer 5R, the horizontally polarized video light coming from the left-eye image display device 1L is left-eye applied to the left eye. Passes the analyzer 5L and reaches the left eye. On the other hand, vertically polarized video light coming from the right-eye image display device 1R passes through the analyzer 5R attached to the right eye and reaches the right eye, so that the observer can experience a stereoscopic effect with the parallax of both eyes.

Patent Publication 2008-191399

However, the conventional stereoscopic display device described in Patent Document 1 is configured to view linearly polarized image light through half mirrors having the same reflectance and transmittance, and generally has such characteristics. Half mirrors are expensive. On the other hand, when an inexpensive half mirror is used, there is a problem that a good three-dimensional image cannot be obtained because the characteristics of linearly polarized light are destroyed in addition to the low transmittance.

In addition, it is necessary to accurately arrange the angle and the distance between the two image display devices for the left eye and the right eye, and when the two image display devices are individually installed in a housing, the two image display devices are displayed. There is a problem that it is difficult to accurately adjust the relative angle and distance of the apparatus.

In view of the above, the present invention has an object to realize an apparatus that can be manufactured at low cost and can obtain a good stereoscopic image by accurate assembly.

In order to solve the above-mentioned problems, the stereoscopic display device according to claim 1 and claim 2 includes a transparent resin plate instead of a half mirror in which a metal or a dielectric is vapor-deposited on the surface and the reflectance and transmittance are adjusted. The transmitted light is increased by using a transparent plate that has been processed into a flat plate. At this time, the two image display devices are installed at an angle larger than 90 degrees and arranged so that the incident angle from the two image display devices to the transparent plate is large, and images generated by the two image display devices The reflectance of the transparent plate is increased by adjusting the polarization direction of the light of the image reflected by the transparent plate so as to be a direction perpendicular to the incident surface to the transparent plate, and the two image displays Make sure that enough light from the device is obtained.

The stereoscopic display device according to claim 3 has a structure in which two image display devices are fixed and integrated at an angle larger than 90 degrees and close to 180 degrees, thereby displaying two image displays. It is easy for the device to be assembled with a relatively accurate angle and distance.

The present invention has the following effects.
According to the first and second aspects of the present invention, since a sufficient amount of image light can be secured even if a transparent plate made of an inexpensive material is used instead of a half mirror, an apparatus capable of obtaining a good stereoscopic image at low cost. Can be realized.

According to the third aspect of the present invention, it is easy to manufacture parts of the image display device and to accurately assemble the image display device, so that a low-cost stereoscopic display device can be realized.

Furthermore, by using the present invention as an inexpensive teaching material, the child is interested in the principle and has a good opportunity to learn the basics of optics.

It is a block diagram of the typical Example in the three-dimensional display apparatus of this invention. It is a block diagram of an example of the conventional stereoscopic display apparatus. It is a block diagram of another Example in the three-dimensional display apparatus of this invention.

Hereinafter, with reference to FIG.3 and FIG.1, the example of the form for implementing the three-dimensional display apparatus of this invention is demonstrated.

FIG. 3 is a configuration diagram showing the stereoscopic display device of this example as a whole. The image display device 11 includes a left-eye image display device 11L that displays a left-eye screen each having a rectangular shape, and a right-eye image display device 11R that displays a right-eye screen, and one side of the left-eye image display device 11L. And the right-eye image display device 11R are integrated so as to share one side, and the angle between the left-eye image display device 11L and the right-eye image display device 11R is fixed at 150 degrees. . At this time, the left-eye image display device 11L is positioned in front of the observation window 16 so that the screen is vertical, and the right-eye image display device 11R is installed below the left-eye image display device 11L.

The polarization direction of the light of the image of the left-eye image display device 11L and the polarization direction of the light of the image of the right-eye image display device 11R are perpendicular to both the left-eye image display device 11L and the right-eye image display device 11R. The direction is in the correct plane. At this time, the polarization direction of the light of the image of the left-eye image display device 11L is the vertical direction. The polarization direction of the image light of the right-eye image display device 11R is converted to the horizontal direction by transmitting through the half-wave plate 12 and the polarizer 13.

A rectangular transparent plate 14 made of a resin material that transmits light well is 15 degrees downward with respect to the horizontal plane so as to form the same angle with respect to each of the right-eye image display device 11R and the left-eye image display device 11L. Install so as to form a surface.

At this time, the left-eye image display device 11L and the right-eye image display device 11R are symmetric with respect to the reflecting surface of the transparent plate 14 (the surface facing the right-eye image display device). The optical path lengths of the image light from the device 11L and the image light of the right-eye image display device 11R are equal (when the influence of refraction at the transparent plate 14 can be ignored).

Reference numeral 15 denotes polarized glasses worn by an observer, 15L and 15R are left-eye and right-eye analyzers, the left-eye analyzer 15L has a vertical polarization direction, and the right-eye analyzer 15R is a horizontal polarization. To have a direction.

Next, the operation of this example will be described. The image light from the right-eye image display device 11R passes through the half-wave plate 12 and the horizontal polarizer 13 so that the image light becomes horizontal linearly polarized light, and the polarization direction thereof is the transparent plate 14. It becomes perpendicular to the incident surface. On the other hand, the polarization direction of the light of the image from the left-eye image display device 11 </ b> L is a vertical direction and is a direction in the incident surface of the transparent plate 14.

In optics, it is well known that when linearly polarized light enters a medium having a higher refractive index than air, the reflectivity increases at a large incident angle, but the polarization direction of the light is perpendicular to the incident surface. It is known that the reflectance will be further increased if such a selection is made.

The light of the image from the right-eye image display device 11R is incident on the transparent plate 14 at a large incident angle of 75 degrees, and the polarization direction is horizontal and perpendicular to the incident surface. The reflectance at becomes large and a large amount of light can be obtained.

On the other hand, although the image light from the left-eye image display device 11L also enters the transparent plate at an incident angle as large as 75 degrees, the polarization direction becomes the vertical direction and becomes the direction in the incident plane. The decrease in transmittance at the plate is small.

Here, when an observer observes from the observation window 16 with the left-eye analyzer 15L and the right-eye analyzer 15R, light of a vertically polarized linearly-polarized image coming from the left-eye image display device 11L. Passes through the left eye analyzer 15L in the vertical direction attached to the left eye and continues to the left eye. On the other hand, the horizontally linearly polarized image light coming from the right-eye image display device 11R via the half-wave plate 12 and the polarizer 13 passes through the right-eye analyzer 15R applied to the right eye and passes through the right-eye analyzer 15R. Therefore, the observer can experience a stereoscopic effect with the parallax of both eyes.

According to this example, the left-eye image display device 11L and the right-eye image display device 11R are installed at a large angle, and the polarization of an image obtained by reflecting the transparent plate 14 of the right-eye image display device 11R is obtained. Since the direction is horizontal, the polarization direction of the image of the right-eye image display device 11R is perpendicular to the incident surface incident on the transparent plate 14 and has a large incident angle, so that the reflectance increases. A sufficient amount of reflected light can be obtained. Thereby, it is not necessary to use an expensive half mirror, and an apparatus capable of obtaining an inexpensive and good stereoscopic image can be realized.

FIG. 1 shows an example of another application configuration for carrying out the present invention.
Another application of the present invention relates to a teaching material that makes it possible to easily experience a 3D image by utilizing basic light properties such as reflection of linearly polarized light. Although the appearance of products using 3D technology such as movies and television is a good opportunity to learn the basics of optics including polarized light, there are few inexpensive things that can easily learn the principles as teaching materials.

An image sheet 21, a left-eye polarizer 23L, a right-eye polarizer 23R, a transparent plate 24, a left-eye analyzer 25L, and a right-eye analyzer 25R are arranged in a casing 27 having a wall whose inner surface is painted black. This shows the configuration, and shows a state in which a part of the wall 27a of the housing 27 is opened.

One side of the left-eye polarizer 23L, one side of the right-eye polarizer 23R, and one side of the transparent plate 24 each having a rectangular shape are in contact with each other. The left-eye polarizer 23L and the right-eye polarizer 23R are installed at an angle of 150 degrees with respect to each other and at the same angle of 75 degrees from the transparent plate 24.

The polarization direction of the right-eye polarizer 23 </ b> R is adjusted to a direction parallel to the intersection line between the plane of the right-eye polarizer 23 </ b> R and the plane of the transparent plate 24. On the other hand, the polarization direction of the left-eye polarizer 23L is adjusted to an in-plane direction perpendicular to both the left-eye polarizer 23L and the transparent plate 24.

The left-eye analyzer 25L and the right-eye analyzer 25R are half the size of the left-eye polarizer 23L and have a rectangular shape, and are parallel to the left-eye polarizer 23L with the transparent plate 24 in between. It is installed to be in front. One side of the left-eye analyzer 25L is in contact with one side of the right-eye analyzer 25R, and the direction in which the side is in contact with one side of the left-eye polarizer 23L and one side of the right-eye polarizer 23R is in contact with each other. It is installed so as to be vertical with respect to it. The polarization direction of the left-eye analyzer 25L has the same polarization direction as that of the left-eye polarizer 23L, and the polarization direction of the right-eye analyzer 25R is adjusted to have the same polarization direction as that of the right-eye polarizer 23R. is doing.

The image sheet 21 is printed such that a left-eye image 21L and a right-eye image 21R are arranged in line symmetry with each other, and light from a light source outside the housing 27 is transmitted to the left-eye. The image light and the right-eye image light are generated. The image sheet 21 is bent at 150 degrees along the symmetry line of the left-eye image 21L and the right-eye image 21R, and is installed so as to be in close contact with the left-eye polarizer 23L and the right-eye polarizer 23R from the outside. Yes.

The light from the outside of the casing 27 is transmitted through the casing 27 except for the positions where the left-eye polarizer 23L, the right-eye polarizer 23R, the left-eye analyzer 25L, and the right-eye analyzer 25R are arranged. It is blocked.

According to this example, if one point of the left-eye image 21L and one point of the left-eye image 21R corresponding to the left-eye image 21L are arranged at the same distance from the transparent plate 24, the left-eye image 21L The optical path length traveled by the light passing through the transparent plate 24 is equal to the optical path length traveled by the light from the right-eye image 21R reflected by the transparent plate 24, and the left-eye image 21L and the right-eye image. The image 21R travels in the same optical path after being synthesized by the transparent plate 24 and reaches the left-eye analyzer 25L or the right-eye analyzer 25R (when the influence of refraction on the transparent plate 24 is small).

The polarization direction of the light from the right-eye image 21R is perpendicular to the incident surface incident on the transparent plate 24 by the right-eye polarizer 23R, and the incident angle is a large value of 75 degrees. Therefore, the reflectance of the transparent plate 24 is increased, and a sufficient amount of light from the right-eye image 21R is obtained.

Since the light from the right-eye image 21R passes only through the right-eye analyzer 25R having the same polarization direction as the right-eye polarizer 23R, it is visually recognized only by the observer's right eye. On the other hand, since the polarization direction of the light from the left-eye image 21L passes only through the left-eye analyzer 25L having the same polarization direction as the left-eye polarizer 23L, it is visually recognized only by the left eye of the observer. With the operation of the above configuration, the observer can experience a stereoscopic image.

However, since the light from the left-eye image 21L is refracted when passing through the transparent plate 24, the optical path is shifted. In order to cope with this, it is necessary to adjust the position of the reflective surface of the transparent plate 24 from a position that is the axis of symmetry between the left-eye image 21L and the right-eye image 21R. Also at this time, the angle formed by the portion of the left-eye image 21L of the image sheet 21 and the transparent plate 24 is equal to the angle formed by the portion of the right-eye image 21R of the image sheet 21 and the transparent plate 24. It is kept.

In the embodiment described above, the angle formed by the two image display devices and the angle of the image sheet are 150 degrees, but the angle is not limited to this. When the transparent plate has a refractive index of 1.52, if it is 140 degrees (incident angle 70 degrees), a reflectance of 30% or more, which is the same as that of the half mirror, can be obtained. Therefore, if the angle formed by the two image display devices is 140 degrees or more, it is an appropriate condition for carrying out the present invention.

As the image display device and the image sheet in the above-described invention, any device capable of generating an image by transmitting light or emitting light itself such as a film, a liquid crystal, and EL can be applied.

Further, as the material of the transparent plate in the invention described above, any material can be applied as long as it transmits light and has a refractive index larger than that of air, such as glass, acrylic and polycarbonate. However, in order to increase the reflectance, a material having a higher refractive index is preferable.

1L ... left eye image display device, 1R ... right eye image display device,
2 ... 1/2 wavelength plate, 3R ... right eye polarizer,
4 ... Transparent plate,
5 ... 3D glasses, 5L ... left eye analyzer, 5R ... right eye analyzer,
6 ... Observation window, 7 ... Housing,
DESCRIPTION OF SYMBOLS 11 ... Image display apparatus, 11L ... Image display apparatus for left eyes, 11R ... Image display apparatus for right eyes,
12 ... 1/2 wavelength plate, 13R ... right eye polarizer,
14 ... half mirror,
15 ... 3D glasses, 15L ... left eye analyzer, 15R ... right eye analyzer,
16 ... Observation window, 17 ... Housing,
21 ... Image sheet, 21L ... Left eye image, 21R ... Right eye image 23L ... Left eye polarizer, 23R ... Right eye polarizer,
24 ... Transparent plate,
25L ... left eye analyzer, 25R ... right eye analyzer,
26 ... Observation window, 27 ... Housing,
27a: Wall developed so that the inside of the housing can be seen

Claims (3)

  An angle formed by the first flat plate, the second flat plate, and the third flat plate, the angle formed by the first flat plate and the third flat plate is formed by the first flat plate and the third flat plate. The first flat plate emits light or the light of the image generated by transmitting light through the first flat plate passes through the third flat plate, and the second flat plate is arranged to be equal to a corner. The light of the image generated when the flat plate emits light or the light passes through the second flat plate is reflected by the third flat plate, and the image generated by the first flat plate and the second In a stereoscopic display device having a mechanism in which an image generated by a flat plate is synthesized on the third flat plate, the second flat plate is made of a resin or glass, and the surface is not coated with a metal or dielectric film. A plate and the first flat plate and the second flat plate. Stereoscopic display device angle between each other is characterized in that it is installed to be greater than 90 degrees   2. The stereoscopic display device according to claim 1, wherein a polarizing plate and / or a wave plate is provided on at least one of the first flat plate and the second flat plate, thereby changing the second flat plate to the third flat plate. The polarization direction of the incident light is adjusted so as to be parallel to the intersecting line formed by the plane of the second flat plate and the plane of the third flat plate, and from the first flat plate to the third flat plate. A stereoscopic display device characterized in that the polarization direction of light incident on the flat plate is adjusted to be in a plane perpendicular to both the first flat plate and the third flat plate.   3. The stereoscopic display device according to claim 1, wherein the first flat plate and the second flat plate are manufactured as an integrated part.

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