JPH09281602A - Polarizing screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of wrinkles and distortions and to improve video quality by using a form memory sheet storing a form. SOLUTION: This polarizing screen 10 has the form memory sheet 12 which memorizes the form so as to maintain a specified plane or curved surface, a video light reflection sheet 14 which is deposited on the form memory sheet 12 and specularly reflect video light (a), a polarizing sheet 16 which is deposited on the video light reflection surface 14 and a scattering sheet 18 which is deposited on the polarizing sheet 16. The form memory sheet 12 is formed by a shape memory resin, etc., and functions as a substrate sheet of the polarizing screen 10. The form memory sheet 12 holds the prescribed form (plane or curved surface) at the time of production by the restitutive force by the form memory characteristic to the external force leading to the wrinkles and distortions. As a result, the screen surface which is free from the wrinkles and curving of the ends and is taut when spread is embodied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarizing screen in which the contrast of an image is improved by using a polarizing sheet.

[0002]

2. Description of the Related Art A conventional polarizing screen includes a thick plastic sheet which functions as a screen substrate, an image light reflecting sheet which is attached to the plastic sheet and which specularly reflects image light, and the image light reflecting sheet. And a scattering sheet attached on the polarizing sheet.

Image light projected from a liquid crystal projector is polarized according to the principle of a liquid crystal light valve. The polarization direction of the polarizing sheet is matched with the polarization direction of the image light. Therefore, the image light passes through the polarizing sheet as it is. On the other hand, in the room illumination light, a component orthogonal to the polarization direction of the polarizing sheet is blocked by the polarizing sheet. As a result, the contrast of the image formed on the polarizing screen surface is improved.

[0004]

However, the conventional polarizing screen has a problem that wrinkles, distortions and the like are likely to occur at the time of winding. Therefore, the image quality is deteriorated because the brightness of the image is partially changed due to the wrinkles generated on the polarizing screen and the curvature of the end portion. In particular, since the polarizing screen uses specular reflection, it is easily affected by wrinkles and distortion. Further, a bead screen whose image light reflection surface is a scattering type has characteristics that are unsuitable for a polarizing screen, although the image quality is unlikely to deteriorate even if wrinkles or distortions occur.

[0005]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a polarizing screen with improved image quality by preventing the occurrence of wrinkles and distortion.

[0006]

A polarizing sheet according to the present invention includes a shape memory sheet that stores a shape so as to maintain a constant flat surface or a curved surface, and a shape memory sheet that is attached to the shape memory sheet and has a positive image light. An image light reflection sheet that reflects light, a polarizing sheet attached on the image light reflection sheet, and a scattering sheet attached on the polarizing sheet. Examples of the material of the shape memory sheet include a shape memory fiber that has been put into practical use in recent years as clothes that are less likely to wrinkle, or a well-known shape memory resin or shape memory alloy. Shape memory fibers are commercially available as shape memory shirts, shape memory pants, shape memory suits and the like that are less likely to wrinkle. Examples of the shape memory resin include a styrene-based hybrid polymer in which a polystyrene unit and a polybutadiene unit are composited, polynorbornene, dimethylformaside, and the like. The shape memory alloy is, for example, a nickel-titanium alloy processed into a plate shape, a foil shape, or a fiber shape.

In the polarizing screen according to the present invention, even if it is deformed by an external force during winding after use, unfolding before use or handling during use, it is restored by the restoring force of the shape memory sheet. Therefore, there are no wrinkles or bends at the ends,
A tight screen surface is obtained.

[0008]

1 and 2 show an embodiment of a polarizing screen according to the present invention, FIG. 1 is a partially enlarged sectional view, and FIG. 2 is an overall configuration diagram. Hereinafter, description will be given with reference to these drawings.

The polarizing screen 10 according to the present invention includes a morphological memory sheet 12 in which the morphology is stored so as to maintain a constant flat surface or curved surface, and an image which is attached to the morphological memory sheet 12 and specularly reflects the image light a. The light reflection sheet 14, the polarization sheet 16 attached on the image light reflection sheet 14, and the scattering sheet 18 attached on the polarization sheet 16 are provided. A rotating shaft 20 is fixed to the upper end of the polarizing screen 10, and a weight 22 is fixed to the lower end of the polarizing screen 10. The rotating shaft 20 is rotated by a motor (not shown) or the like, so that the polarization screen 10
To wind or unroll. The weight 22 stretches the polarizing screen 10 by the force of its gravity.

The above-mentioned sheets are bonded together by an adhesive sheet (not shown). The scattering sheet 18 forms the surface of the display surface of the polarizing screen 10 and prevents the image light a from being specularly reflected. Polarizing sheet 1
The polarization direction of 6 matches the polarization direction of the image light a projected from the liquid crystal projector. Therefore, the image light a
Passes through the polarizing sheet 16 as it is. On the other hand, in the room illumination light, a component orthogonal to the polarization direction of the polarizing sheet 16 is blocked by the polarizing sheet 16. As a result, the contrast of the image formed on the surface of the polarizing screen 10 is improved. The image light reflection sheet 14 is formed of, for example, an aluminum foil, and specularly reflects the image light a transmitted through the polarizing sheet 16.

The shape memory sheet 12 is made of a shape memory resin or the like and functions as a base sheet of the polarizing screen 10. Further, the morphological memory sheet 12 retains a predetermined morphology (flat surface or curved surface) at the time of manufacturing by the restoring force due to morphological memory characteristics against external force that causes wrinkles and distortion.

[0012]

According to the present invention, by using the shape memory sheet, it is possible to prevent the occurrence of wrinkles and distortion at the time of winding, and it is also possible to restore the dents and wrinkles caused by the handling during use. , It is possible to realize a taut screen surface without wrinkles or curved edges when deployed. Therefore, wrinkles and distortions are eliminated on the screen surface, and the image quality can be improved.

[Brief description of drawings]

FIG. 1 is a partially enlarged cross-sectional view showing an embodiment of a polarizing screen according to the present invention.

FIG. 2 is an overall configuration diagram showing an embodiment of a polarizing screen according to the present invention.

[Explanation of symbols]

 10 Polarizing Screen 12 Shape Memory Sheet 14 Image Light Reflecting Sheet 16 Polarizing Sheet 18 Scattering Sheet a Image Light

Claims (3)

[Claims] 1. A shape memory sheet in which a shape is stored so as to maintain a constant flat surface or curved surface, an image light reflecting sheet which is attached to the shape memory sheet and specularly reflects image light, and the image light reflection. A polarizing screen comprising a polarizing sheet applied on a sheet and a scattering sheet applied on the polarizing sheet. 2. The polarizing screen according to claim 1, wherein the shape memory sheet is made of a shape memory resin. 3. The polarizing screen according to claim 1, wherein the shape memory sheet is made of a shape memory fiber.