Lenticular lens sheet, display front plate and transmission type projection screen

• US 5,880,887 A
• Filed: 08/14/1997
• Issued: 03/09/1999
• Est. Priority Date: 08/16/1996
• Status: Expired due to Term

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: Goto, Masahiro
• Primary Examiner(s): Ben, Loha
• Application Number:
  US08/911,419
• Time in Patent Office: 572 Days
• Field of Search: 359/619, 359/621, 359/622, 359/626, 359/627, 359/628, 359/454, 359/455, 359/456, 359/457
• US Class Current: 359/626
• CPC Class Codes: G03B 21/625 Lenticular translucent screens

Abstract

A lenticular lens sheet includes a substrate layer, a lens portion having a lenticular lens configuration which is shaped so as to be convex on a light incident face side of the substrate layer and an achromatic or chromatic colored layer formed adjacent to at least a light incident face of the lens portion. The substrate layer is not colored. Alternatively, it is colored thinner than the colored layer. With the arrangement, it is possible to restrict reflection of outside light and enhance the contrast of picture without reducing the intensity of image light so much. Further, it is possible to realize fine pitching of images.

Claims

1. A lenticular lens sheet comprising:

a substrate layer;

a lens portion having a "lenticular lens" configuration which is shaped so as to be convex on a light incident face side of said substrate layer; and

an achromatic or chromatic colored layer formed adjacent to at least a light incident face of said lens portion;

wherein said substrate layer is either non-colored or colored paler than said colored layer.

2. A lenticular lens sheet as claimed in claim 1, wherein said colored layer has a configuration along a shape of said lens portion.

3. A lenticular lens sheet as claimed in claim 1 or 2, wherein said colored layer has a thickness from 0.05 to 1.0 times as large as a pitch of the lenticular lens configuration.

4. A lenticular lens sheet as claimed in claim 1, wherein said colored layer has a thickness less than one a half (1/2) of a thickness of the lenticular lens sheet.

5. A lenticular lens sheet as claimed in claim 1, wherein the lenticular lens configuration of said lens portion has a substantially elliptical cross section and a thickness of said colored layer at the top of the lenticular lens configuration is represented by:

space="preserve" listing-type="equation">t.sub.1 =b-b.sup.2 /(a.sup.2 +b.sup.2).sup.1/2

wherein t₁ is the thickness of said colored layer at the top portion;

a is a transverse diameter of the elliptical cross section; and

b is a longitudinal diameter of the elliptical cross section.

6. A lenticular lens sheet as claimed in claim 1, wherein a thickness of said colored layer is established so as to meet an inequality represented by:

space="preserve" listing-type="equation">t.sub.1 >

t.sub.2

wherein t₁ is a thickness of each center part of said lens portion; and

t₂ is a thickness of each foot part of said lens portion, the thickness being perpendicular to a lens surface thereof.

7. A lenticular lens sheet as claimed in claim 1, wherein at least said colored layer contains additive diffusion agents.

8. A lenticular lens sheet as claimed in claim 7, wherein it is established of an unequal relationship represented by:

space="preserve" listing-type="equation">O≦

C.sub.0 <

C.sub.1

wherein C₀ is a weight concentration of an additive diffusion agents added into said substrate layer; and

C₁ is a weight concentration of said additive diffusion agents added into said colored layer.

9. A lenticular lens sheet as claimed in claim 1, further comprising a diffusion layer which is formed between said colored layer and said substrate layer and into which diffusion agents are mixed, wherein said colored layer does not contain the diffusion agents and said substrate layer is either non-colored or colored paler than said colored layer.

10. A lenticular lens sheet as claimed in claim 1, wherein the lenticular lens configuration includes a portion a tangential line of which exhibits an angle more than a critical angle with respect to a surface of the lenticular lens sheet.

11. A lenticular lens sheet as claimed in claim 1, wherein said substrate layer has a light emitting projection face consisting of a flat surface or a mat surface.

12. A lenticular lens sheet as claimed in claim 11, wherein a thickness of the lenticular lens sheet is more than 1.5 mm.

13. A lenticular lens sheet as claimed in claim 11 or 12, wherein said substrate layer is provided, on a light emitting face thereof, with at least one of an anti-reflection layer, a low reflecting layer, a polarization filtering layer, an anti-static layer, an anti-glare treatment layer and a hard coated treatment layer.

14. A display front plate comprising:

a substrate layer; and

a lens portion having a "lenticular lens" configuration which is shaped so as to be convex on a light incident face side of said substrate layer;

wherein said lens portion has an achromatic or chromatic colored layer formed adjacent to at least a light incident face of said lens portion;

wherein said substrate layer has a light emitting face consisting of a flat surface or a mat surface.

15. A display front plate as claimed in claim 14, wherein said substrate layer is provided, on a light emitting face thereof, with at least one of an anti-reflection layer, a low reflecting layer, a polarization filtering layer, an anti-static layer, an anti-glare treatment layer and a hard coated treatment layer.

16. A transmission type projection screen comprising:

a lenticular lens sheet including;

a substrate layer;

a lens portion having a "lenticular lens" configuration which is shaped so as to be convex on a light incident face side of said substrate layer; and

an achromatic or chromatic colored layer formed adjacent to at least a light incident face of said lens portion;

wherein said substrate layer is either non-colored or colored paler than said colored layer; and

a Fresnel lens sheet arranged on a light source'"'"'s side of said lenticular lens sheet.

17. A transmission type projection screen as claimed in claim 16, further comprising a display front plate arranged on a viewer'"'"'s side of said lenticular lens sheet, wherein said display front plate comprises:

a substrate layer; and

a lens portion having a "lenticular lens" configuration which is shaped so as to be convex on a light incident face side of said substrate layer;

wherein said lens portion has an achromatic or chromatic colored layer formed adjacent to at least a light incident face of said lens portion;

wherein said substrate layer has a light emitting face consisting of a flat surface or a mat surface.

18. A transmission type projection screen as claimed in claim 17, wherein said substrate layer is provided, on a light emitting face thereof, with at least one of an anti-reflection layer, a low reflecting layer, a polarization filtering layer, an anti-static layer, an anti-glare treatment layer and a hard coated treatment.

19. A transmission type projection screen as claimed in any one of claims 16 to 18, wherein said transmission type projection screen has a transmissivity of total light beams from 40 to 70 percent.