Rear-projection screen and rear-projection image display

• US 6,785,048 B2
• Filed: 10/09/2003
• Issued: 08/31/2004
• Est. Priority Date: 08/30/2000
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ikeda, Kenichi, Yamaguchi, Hiroshi
• Primary Examiner(s): Mack, Ricky
• Assistant Examiner(s): THOMAS, BRANDI N
• Application Number:
  US10/682,066
• Publication Number:
  US 20040080821A1
• Time in Patent Office: 327 Days
• Field of Search: 359/453, 359/457, 359/460, 359/456, 359/455, 359/454, 359/443
• US Class Current: 359/453
• CPC Class Codes: G03B 21/62 Translucent screens

Abstract

A rear-projection screen 3, including at least a lenticular lens sheet 32 and a Fresnel lens sheet 31, is configured so that the lenticular lens sheet 32 contains, in a base material thereof made of a resin, light diffusing microparticles made of a resin having a refractive index different from a refractive index of the base material, and the light diffusing microparticles satisfy 0.5 μm≦ΔN1×d1≦0.9 μm, where ΔN1 represents a difference between a refractive index of the light diffusing microparticles and a refractive index of the base material of the lenticular lens sheet, and d1 represents an average particle diameter of the light diffusing microparticles. With this, a rear-projection screen with small wavelength dependency of diffusion characteristics can be provided utilizing only resins with general properties.

Claims

1. A rear-projection display comprising a spatial modulation element, and a rear-projection screen on whose surface on a light-projected side an image formed by the spatial modulation element is projected so that the image is observed from an image-observed side opposite to the light-projected side,

wherein the rear-projection screen includes a first screen element for converting projected light from the spatial modulation element into substantially parallel light, and a second screen element for diffusing the substantially parallel light,

wherein the second screen element includes a lenticular lens array that is provided on the surface on the light-projected side and whose lengthwise direction is directed in a vertical direction, a diffusing layer provided at the image-observed side of the lenticular lens array, and a transparent layer provided between the lenticular lens array and the diffusing layer,

wherein a distance t1 between a light-projected-side surface of the diffusing layer and a focal plane of the lenticular lens array satisfies Formula II-1 below, and a distance t2 between an image-observed-side surface of the diffusing layer and the focal plane of the lenticular lens array satisfies Formula II-2 below:

3. The rear-projection display according to claim 1, wherein the first screen element is a Fresnel lens sheet made of a transparent material containing substantially no diffusing material.

4. The rear-projection display according to claim 1, wherein a light absorbing layer is provided on a light non-transmission portion in a vicinity of the focal plane of the lenticular lens array of the second screen element.

9. The rear-projection display according to claim 1, wherein the first screen element is a Fresnel lens sheet made of a transparent material containing substantially no diffusing material.

2. A rear-projection display comprising a spatial modulation element, and a rear-projection screen on whose surface on a light-projected side an image formed by the spatial modulation element is projected so that the image is observed from an image-observed side opposite to the light-projected side,

wherein the rear-projection screen includes a first screen element for converting projected light from the spatial modulation element into substantially parallel light, and a second screen element for diffusing the substantially parallel light,

wherein the second screen element includes a lenticular lens array that is provided on the surface on the light-projected side and whose length-wise direction is directed in a vertical direction, a diffusing layer provided at the image-observed side of the lenticular lens array, and a transparent layer provided between the lenticular lens array and the diffusing layer,

wherein a distance t1 between a light-projected-side surface of the diffusing layer and a focal plane of the lenticular lens array satisfies Formula II-1 below, and a distance t2 between an image-observed-side surface of the diffusing layer and the focal plane of the lenticular lens array satisfies Formula II-3 below:

10. The rear-projection display according to claim 2, wherein a light absorbing layer is provided on a light non-transmission portion in a vicinity of the focal plane of the lenticular lens array of the second screen element.

5. A rear-projection screen on whose surface on a light-projected side an image formed by a spatial modulation element is projected so that the image is observed from an image-observed side opposite to the light-projected side,

the rear-projection screen comprising:

a first screen element for converting projected light from the spatial modulation element into substantially parallel light; and

a second screen element for diffusing the substantially parallel light,

wherein the second screen element includes a lenticular lens array that is provided on the surface on the light-projected side and whose length-wise direction is directed in a vertical direction, a diffusing layer provided at the image-observed side of the lenticular lens array, and a transparent layer provided between the lenticular lens array and the diffusing layer,

wherein a distance t1 between a light-projected-side surface of the diffusing layer and a focal plane of the lenticular lens array satisfies Formula II-1 below, and a distance t2 between an image-observed-side surface of the diffusing layer and the focal plane of the lenticular lens array satisfies Formula II-5 below;

7. The rear-projection screen according to claim 5, wherein the first screen element is a Fresnel lens sheet made of a transparent material containing substantially no diffusing material.

8. The rear-projection screen according to claim 5, wherein a light absorbing layer is provided on a light non-transmission portion in a vicinity of the focal plane of the lenticular lens array of the second screen element.

6. A rear-projection screen on whose surface on a light-projected side an image formed by a spatial modulation element is projected so that the image is observed from an image-observed side opposite to the light-projected side,

the rear-projection screen comprising:

a first screen element for converting projected light from the spatial modulation element into substantially parallel light; and

a second screen element for diffusing the substantially parallel light,

wherein the second screen element includes a lenticular lens array that is provided on the surface on the light-projected side and whose length-wise direction is directed in a vertical direction, a diffusing layer provided at the image-observed side of the lenticular lens array; and

a transparent layer provided between the lenticular lens array and the diffusing layer,

wherein a distance t1 between a light-projected-side surface of the diffusing layer and a focal plane of the lenticular lens array satisfies Formula II-1 below, and a distance t2 between an image-observed-side surface of the diffusing layer and the focal plane of the lenticular lens array satisfies Formula II-6 below;

11. The rear-projection screen according to claim 6, wherein the first screen element is a Fresnel lens sheet made of a transparent material containing substantially no diffusing material.

12. The rear-projection screen according to claim 6, wherein a light absorbing layer is provided on a light non-transmission portion in a vicinity of the focal plane of the lenticular lens array of the second screen element.