JPH06308633A - Lenticular plate - Google Patents

Abstract

(57) [Summary] [Purpose] A stereoscopic display that uses a lenticular plate to improve the convergence of light from the front, which is the main lobe, and light from diagonal directions, which is the sub-lobe and sub-lobe. Is made sharper when viewed from the front and sharper when viewed obliquely without blurring, and a sharper converged image is obtained when the original images are combined. [Structure] A light-shielding portion is provided along the boundary of the lens, and the effective lens width between the light-shielding portions is smaller than the lens pitch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lenticular plate used for a stereoscopic display, and a lenticular plate used for synthesizing an original image for the stereoscopic display and for stereo shooting of a subject.

[0002]

2. Description of the Related Art An example of the structure of a stereoscopic display using a lenticular plate is shown in FIG. 1, and the basic structure and the stereoscopic principle of a lenticular plate used in a stereoscopic display are shown in FIG. As shown in FIG. 1, the stereoscopic display A
Is a lenticular plate 1 and a film-like sheet (color film or printed matter) 2 attached to the back side of the lenticular plate 1
The lenticular plate 1 has a plate shape in which a plurality of lenses 3 having a cylindrical peripheral surface shape (cylindrical shape) and extending in the vertical direction are arranged side by side in the horizontal direction.

The lenticular plate 1 shown in FIG. 2 has a representation represented by a single lens 3. In reality, the lens 3 has a plate shape in which dozens and hundreds of lenses 3 are arranged side by side. (See FIG. 1), the curvature r, the width (pitch) P, and the thickness t that form the lens 3 are displayed to identify the lenticular plate 1. This lenticular plate 1
On the sheet 2 located on the back surface of the sheet 2, a plurality of (two or more) original images having parallax obtained by photographing from a plurality of left and right directions are divided and linearly compressed (converged image formation). ) And one synthesized image for stereoscopic vision is formed. It should be noted that the method of synthesizing the stereoscopic synthetic image is well known, and the description of the synthetic method is omitted. The composite image for stereoscopic vision, which has a structure required for stereoscopic vision, is obtained by printing on the sheet 2, or by using the sheet 2 as a color film and forming the composite image on the color film. .

When an observer views the stereoscopic display from a predetermined distance, for example, the right eye sees an image (convergent image) α and the left eye sees an image (convergent image) β. The synthetic image required for stereoscopic vision is synthesized from two or more original images as described above, and the images α and β are different images, and the parallax required for stereoscopic vision is between them. From the fact that is included, the observer can see an image having a stereoscopic effect. In this way, the stereoscopic display is configured by the combination of the lenticular plate and the composite image, and can be viewed stereoscopically when viewed from the front. And in a stereoscopic display equipped with a lenticular plate, unlike the method of wearing other red-blue glasses for stereoscopic viewing or the method of wearing polarizing glasses for stereoscopic viewing, stereoscopic viewing is possible without the need for these glasses. It has a great feature. The shape of the lenticular plate 1, that is,
The curvature r, the pitch P, and the thickness t are the size of the stereoscopic display, the number of images to be combined (the number of original images with parallax),
It depends on the distance required for observation.

[0005]

The optical characteristics (spherical aberration) of the lenticular plate will be described with reference to FIG. Since the lenticular plate is a single lens having one curvature, the spherical aberration has a great influence on the light convergence of the lenticular plate. That is, the influence of the spherical aberration is the stereoscopic effect of the image when the stereoscopic display is viewed, and the image viewed through the lenticular plate is very sharp and has a good stereoscopic effect (the depth of the front and rear feeling is deep). To achieve this, very sharp convergence is required. However, as shown in FIG. 3A, in each lens of the lenticular plate, due to the spherical aberration as a single lens, the fire line of k1 converges at the point p1 and the fire line of k2 changes at the point p.
2, the k3 fire line converges to the point p3, and the k4 fire line converges to the point p4. The converged positions are different, and the focal width (w _A ) has a certain spread.

In FIG. 3B, n (refractive index) = 1.53.
The spherical aberration in the case of (PVC plate) is shown, but in the vicinity of the center line of φ = 0 °, the line of fire is s (φ) /r≈2.8 (s:
Focus position φ: incident angle of light r: curvature), that is, the light is focused in the vicinity of 2.8r, and when φ = 90 °, it is focused at about 2.0r. As can be seen from the graph shown in FIG. 2, when the shape of the lenticular plate (shape of the lens) has a large curvature r and a small pitch P, the light is condensed in the vicinity of 2.8r, and its convergence state is sharp. However, when the curvature r is small and the pitch P is large, the light is 2.8r to 2.0r.
The light is focused on, and its convergence state becomes unsharp.

When actually performing stereoscopic vision using a lenticular plate, as shown in FIG. 4, a stereoscopic vision by a main lobe (lobe: bundle of fire rays) (that is, front view)
In some cases, stereoscopic viewing may be performed in an oblique direction due to the sub-lobe and the sub-lobe. In FIG. 4, a is a stereoscopic view position by the main lobe, b is a stereoscopic view position by the sublobe, and c is a stereoscopic view position by the sub-lobe. As shown in FIG. 5 (a), when the stereoscopic view is performed only with the main lobe, the shape is viewed from the front, so that the range of light collected by the lenticular plate is scattered like 2.8r to 2.0r. However, the properly condensed light corresponds to the image on the back side, and the reduction of the stereoscopic effect is not so noticeable. The stereoscopic display can be viewed stereoscopically from the side lobes and side-by-side lobes,
This is a feature that many people can simultaneously see in stereoscopic view using a lenticular plate. However, as shown in FIG. 5B, when viewed from an oblique direction by the side lobe, it is difficult to properly collect light on the composite image on the sheet 2, and thus the stereoscopic image becomes a blurred stereoscopic image. (The same is true for stereoscopic viewing with the sub-lobe).

On the other hand, when a composite image is obtained from a plurality of original images, each of the original images is exposed to the composite image film through the lenticular plate for composition, and the color film exposed each time is exposed. The lenticular plate for photography is moved fixedly (1 pitch / number of original images) while being in close contact with the color film. Also, the subject is rotated by a predetermined angle, and the image is divided and compressed on the exposed film via the lenticular plate for photography, and the lenticular plate for photography is moved by the required amount for each photography. It may also form a composite image. For this synthesis, the lenticular plate for photographing is used under the same conditions as the above lenticular plate for observation, but if the convergence property in the main lobe is high, a sharper convergent image can be formed on the film for composite image, From this point as well, it is desired to improve the convergence of the lenticular plate.

In view of the above situation, it is an object of the present invention to improve the convergence of light from the front, which is a main lobe, and light from an oblique direction, which is a sublobe or a sublobe. In addition, the stereoscopic display using the lenticular plate can be seen sharper from the front, and can be viewed stereoscopically without blurring even when viewed obliquely, and the converged image at the time of synthesis can be obtained sharper. The purpose is to

[0010]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned problems, and a light-shielding portion is provided along the boundary portion of the lens, and the effective lens width between the light-shielding portions is smaller than the pitch of the lens. By providing a lenticular plate characterized by the above, the above-mentioned problems are solved.

[0011]

In the present invention, since light-shielding portions are provided at both ends of each lens of the lenticular plate, and the lens effective width is smaller than the pitch, the effective portion of each lens is the central portion of the lens, that is, the range of small φ. Under the same condition as that of the lens having the large curvature r and the small pitch P described above, the light is condensed in the vicinity of 2.8 r, and the converged state becomes sharp.

[0012]

EXAMPLES The present invention will now be described in detail with reference to the examples shown in FIGS. Here, the shape of the conventional lenticular plate is r = 1 mm, P = 1.5 mm, t = 2.6 mm, φ = 4
At 8.6 °, the caustic line exists at s (φ) /r=2.5 to 2.8 from FIG. 3B, indicating that the convergence is poor. It is also shown that the blurring when the lenticular plate is seen from an oblique direction becomes noticeable. In the lenticular plate 1 according to the embodiment of the present invention, the shape (r, P, t,
φ) is the same as the conventional lenticular plate described above. Then, as shown in FIG. 6, each boundary portion 4 of the lens 3 is
A light-shielding portion 5 is provided along with, and a lens effective width (use width) 6 between the light-shielding portions 5 is placed at the center of the lens 3,
The effective lens width 6 is ½ of the pitch P. As shown in FIG. 6, the convergence of the lenticular plate 1 of this embodiment is far greater than that of the conventional lenticular plate (see FIG. 5A) even in the main lobe light and the sublobe light. It can be confirmed that the property is improved.

The light-shielding portion 5 is obtained by painting black, and the light-shielding portion which does not transmit light does not affect the image quality. The reason will be described below. When observing the human eye physiologically and optically, if the pitch of the lenticular plate is P ≦ observation distance / (1700 to 3500), the eye cannot be resolved and no black line is seen. Of course, when viewed as a surface, the area of black occupies 1/2 of the whole product, so the screen becomes darker and darker, but the fact that it becomes darker means that the contrast is improved, and this contrast is improved. The benefits are greater.

Further, when the lenticular plate 1 having the light-shielding portion is used as a lenticular plate for synthesis, even if the light-shielding portion is made of black paint, it does not affect the exposure and the convergence property. Therefore, a sharp image can be formed on the film side.

The light-shielding portion is located at both ends of each lens in order to exclude the large φ portion of the lenticular plate.
As shown in FIG. 7, the shape of the lenticular plate 1 is left as it is, and the light shielding portion 5 is provided on the boundary portion 4, and the shape of the boundary portion 4 is made flat as shown in FIG. Alternatively, as shown in FIG. 8, the boundary portion 4 may be formed in a flattened shape so as to make it easier to ride. The light-shielding portion 5 is formed by coating or printing with a black paint or black ink, or by arranging it in the boundary portion 4 using a light-shielding material such as a resin or a metal substance containing a light-shielding substance. May be.

In the lenticular plate, the effective lens width is

[0017]

[Equation 1]

Within the range, good convergence can be obtained without hindering the use of the stereoscopic display, and it covers the range corresponding to the stepwise changing aperture of a general camera. .

[0019]

As described above, according to the present invention,
It is characterized in that a light-shielding portion is provided along the boundary portion of the lens, and the effective lens width between the light-shielding portions is smaller than the lens pitch. This improves the convergence of light in each lens, and when the back surface of this lenticular plate arranges a composite image to form a stereoscopic display, the light is properly converged to the composite image. It becomes a state, and it becomes possible to perform a sharper stereoscopic view. Then, even when viewed from the diagonal direction of the sub-lobe and the sub-lobe, the stereoscopic view becomes sharp and the left and right stereoscopic regions of the stereoscopic display are expanded. Further, the contrast can be easily improved by a simple method in which the light shielding portion is made black. From these points, it is possible to greatly improve the quality (image quality) of the stereoscopic display.

On the other hand, since the composite image is created first when finishing as a product (stereoscopic display), the convergence image in the composite image is sharp in consideration of the deterioration in the later process. The better. In this respect,
In the lenticular plate of the present invention, the convergence property due to the front light is significantly sharper than that of the conventional one, so that it can be used as an object for photographing and a composition, and a sharp composite image can be obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a stereoscopic display.

FIG. 2 is an explanatory diagram showing a basic configuration of a lenticular plate and a principle of stereoscopic vision.

FIG. 3 is an explanatory diagram showing optical characteristics (spherical aberration) of a lenticular plate, (a) showing a caustic line passing through a lens,
(B) shows the relationship between the focal position and the light beam incident position.

FIG. 4 is an explanatory diagram showing stereoscopic positions of a main lobe, a sub-lobe, and a sub-lobe with respect to a lenticular plate.

5 (a) and 5 (b) are explanatory diagrams showing how a fire line travels with respect to a lenticular plate, in which (a) shows convergence by main lobe light and (b) shows convergence by sublobe light.

6A and 6B are explanatory views showing the convergence of light in one embodiment of the lenticular plate according to the present invention, in which FIG. 6A shows the convergence by the main lobe light, and FIG. 6B shows the convergence by the sublobe light. .

FIG. 7 is an explanatory diagram showing another embodiment.

FIG. 8 is an explanatory view showing another embodiment of the present invention.

[Explanation of symbols]

 1 ... Lenticular plate 3 ... Lens 4 ... Border part 5 ... Light-shielding part 6 ... Lens effective width

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Tetsuro Komuro 1-5-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. (72) Inventor Satomi Arai 1-5-1 Taito, Taito-ku, Tokyo Toppan Imprint Co., Ltd.

Claims (1)

[Claims] 1. A lenticular plate, characterized in that a light-shielding portion is provided along a boundary portion of the lens, and an effective lens width between the light-shielding portions is smaller than a lens pitch.