JPH1039417A - Opaque screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove a hot spot on the surface of a screen and to enhance observed image quality by providing a light shielding part in a part including the top of the convex part of each unit lens of a lens array. SOLUTION: The light shielding part 2 is provided in the part including the top of the convex part of each unit lens 1 of the lens array. In other words, application to a lenticular sheet, a fly eye lens sheet where microlenses are arranged like a matrix and a lens sheet where toric lenses are arranged like the matrix is attained. Further, a light shielding layer can be easily formed by printing or a transfer, in the vicinity of the top of the convex part of each unit lens 1 and an arbitrary method can be suitably adopted. Thus, the light shielding part 2 is provided in the part including the top of the convex part of the unit lens 1 constituting the lens array and a reflection layer 3 is formed on a counter-lens part side. Moreover, a light shielding part 4 is formed in the part where light is not converged by the lens array (the noncondensing part, of the unit lens 1), at the time of irradiating the screen with the light from a projector.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection screen (reflection screen) which is disposed on a projection side of a variety of projection devices and observes reflected (imaged) image light.

[0002]

2. Description of the Related Art At conferences and projections, devices such as OHP (overhead projectors) and projectors using 16 mm or 8 mm films have been used. The opportunity to watch movies and the like by projection is increasing.

[0003] There are various types of screens arranged on the side to be projected with respect to these devices, and they are selected and used according to the application.

[0004] There is known a reflection type screen comprising a lens sheet having a lens array formed on the viewer and the projector side and a light reflection layer formed on the opposite side. Among them, a semi-cylindrical convex lens is known. A type of screen using a lenticular sheet having a side-by-side cylindrical lens group (hereinafter referred to as a lenticular screen) is typical.

[0005] A lenticular screen can increase the amount of light reflected to the light source (projector) side by making the reflected light recursive by the function of each unit lens. Accordingly, an image in which the entire projection surface is bright can be observed regardless of the widening of the lens of the projection device (enlargement of the projection angle) and the enlargement of the projection surface. The lenticular screen is disclosed in U.S. Pat.
-204927 and the like.

In the lenticular screen, since the cylindrical lens group faces the light source (projector) and the observer, a hot spot is generated near the top of the convex portion of each unit lens due to the reflection of the projection light, and the surface of the screen is damaged. It will be seen as glare.

[0007] Not only a lenticular screen but also a reflective screen of a type constituted by a lens sheet. Even if the unit lens is a micro lens or a toric lens, the above-mentioned hot spot (the local area near the top of the convex part of the unit lens) Glare).

To reduce the problem of hot spots,
It is a practical measure to form a diffusion layer on the surface of the lens array or to perform a mat (rough surface) treatment to such an extent that the lens function is not affected. However, the optical characteristics of the screen (S / N ratio) ) Will be degraded.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a reflection type screen comprising a lens sheet which can eliminate the problem of a hot spot without deteriorating the optical characteristics (S / N ratio) of the screen. Aim.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a reflection type screen comprising a lens sheet having a lens array formed on a viewer and a projector side and having at least a light reflection layer formed on the opposite side. A light shielding portion is provided at a portion including the top of the convex portion of each unit lens.

In the light-shielding portion, a portion including the top of the convex portion of each unit lens of the lens array may be formed in a projection shape, and a light-shielding layer may be formed on the projection.

Further, when light is emitted from the projector to the lens array, a light-shielding portion may be provided in a portion not converged by the lens array.

The shape of the light-shielding portion changes according to the shape of the lens array. For example, a micro lens has a circular shape, and a cylindrical lens has a band shape.

If the size of the light-shielding portion is made larger than necessary, the screen may be perceived as being dark. Therefore, the minimum size that satisfies the condition that the projection light reflected from the projector surface from the projector is not visible to the observer. Is fine.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B are explanatory diagrams of a case where the present invention is applied to various lens sheets. FIG. 1A is a lenticular sheet, and FIG. 1B is a fly-eye lens sheet in which micro lenses are arranged in a matrix. FIG. 1C is a perspective view of a lens sheet on which toric lenses are arranged in a matrix.

It is easy to form a light-shielding layer near the top of the convex portion of each unit lens by printing or transfer, and any method can be adopted as appropriate.

FIG. 2 is an explanatory sectional view showing a unit lens showing the optical characteristics of the reflective screen of the present invention.
A light-shielding portion 2 is provided at a portion including the top of the convex portion of the unit lens 1 constituting the lens array, and a reflection layer 3 is formed on the side opposite to the lens portion. The reflective layer 3 may simply exhibit specular reflection characteristics, but may be subjected to a diffusion process so that the light is reflected at a wide angle. Further, when the screen is irradiated with light from the projector, a light-shielding portion 4 is provided on a portion not condensed by the lens array (a non-condensing portion of the unit lens 1).
Are formed.

The incident light 5 which is an image from a projector (not shown) is refracted by the unit lens 1 and is reflected by the reflection surface (reflection layer 3)
And the reflected (diffused) light is refracted by the unit lens 1 again and reaches the observer (not shown).

Light other than the image from the projector that enters the screen (for example, room lighting or sunlight) has a different incident angle to the screen than the image light, and is condensed on the light shielding unit 4 by the lens array. It does not contribute to the reflection on the reflection layer 3.

The problem here is, of the light 6 reflected on the surface of the unit lens 1, the reflected light 9 reaching the observer and forming a hot spot. As shown in the figure, the reflected light 9 constituting the hot spot is the reflected light at the portion including the top of the convex portion of the unit lens, and in the screen of the present invention in which the light shielding portion 2 is provided at that portion, the reflected light 9 No problem occurs.

[0021]

【The invention's effect】

1) Hot spots on the screen surface can be removed, contributing to improvement of the observed image quality. 2) As a countermeasure against hot spots, it is possible to omit the diffusion treatment on the screen surface. Therefore, the optical characteristics (S / N ratio) of the screen are not degraded, the screen gain (brightness of the reflected light) is increased, and the observed image quality is improved.

[0022]

[Brief description of the drawings]

FIGS. 1A to 1C are explanatory diagrams illustrating a case where the present invention is applied to various lens sheets.

FIG. 2 is a cross-sectional explanatory view showing the optical characteristics of the reflective screen of the present invention for a certain unit lens.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Unit lens 2 ... Shield part 3 ... Reflective layer 4 ... Shield part 5 ... Incident light 6 ... Reflected light on a lens surface 9 ... Reflected light which comprises a hot spot

Claims (6)

[Claims] 1. A reflection type screen comprising a lens sheet having a lens array formed on a viewer and a projector side and having at least a light reflection layer formed on the opposite side, wherein a top of a convex portion of each unit lens of the lens array is provided. A reflection type screen, wherein a light-shielding portion is provided in a portion including the following. 2. The reflection type screen according to claim 1, wherein a portion including a top of the convex portion of each unit lens of the lens array is formed in a projection shape, and a light shielding layer is formed on the projection. 3. The reflection type screen according to claim 1, wherein a light-shielding portion is provided at a portion which is not converged by the lens array when light is emitted from the projector to the lens array. 4. The reflection type screen according to claim 1, wherein the lens sheet is a lenticular sheet having a cylindrical lens group in which semi-cylindrical convex lenses are juxtaposed. 5. The lens sheet according to claim 1, wherein the lens sheet is a fly-eye lens sheet in which micro lenses are arranged in a matrix.
The reflective screen according to claim 3. 6. The reflection type screen according to claim 1, wherein the lens sheet is a lens sheet in which toric lenses are arranged in a matrix.