Projection type image display apparatus

• US 20070229948A1
• Filed: 08/30/2006
• Published: 10/04/2007
• Est. Priority Date: 03/31/2006
• Status: Active Grant

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hirata, Koji, Ogura, Naoyuki, Imafuku, Daisuke
• Granted Patent: US 7,433,121 B2
• Time in Patent Office: Days
• US Class Current: 359/443
• CPC Class Codes: G03B 21/625 Lenticular translucent screens

Abstract

A screen is hung from a screen frame with hanging members bonded to the upper side of a front sheet. Supporting members are disposed on the lower side of the front sheet and, by mounting a Fresnel lens sheet on the supporting members, a tension is given by its weight to the front sheet in the vertical direction. Further, a tension in the horizontal direction is given to the front sheet. Long holes are so formed in the hanging members that the hanging members on the right and left sides of the screen by expansion or contraction of the screen are made greater in the extent of shifting in the horizontal direction than the hanging member in the central part.

Claims

1. A projection type image display apparatus comprising:

a screen on which an image is to be projected,

a screen frame which is fixed to a housing of said display apparatus and from which said screen is hung, and

a plurality of hanging members to be fitted to said screen frame, disposed at least at the center of the upper side and on the right and left sides of the screen, wherein;

the extents of shifting of the hanging members disposed on the right and left sides of said screen in the horizontal direction are made greater than the extent of shifting of the hanging member disposed at the center of said screen in the horizontal direction.

2. The projection type image display apparatus as claimed in claim 1, wherein said screen comprises a front sheet for diffusing lights of the image at least in the horizontal direction and a Fresnel lens sheet which is arranged on the light incidence side of the front sheet and in which a Fresnel lens is formed, wherein:

said plurality of hanging members are disposed on the upper side of said front sheet.

3. The projection type image display apparatus as claimed in claim 2, wherein a supporting member whose section is L-shaped is disposed on the lower side of said front sheet, said Fresnel lens sheet is mounted on said supporting member, and tension is given by the weight of the Fresnel lens sheet in the vertical direction of said front sheet.

4. The projection type image display apparatus as claimed in claim 3, wherein coupling members to be coupled with tensioning members for giving tension in the horizontal direction of said front sheet are disposed at the right and left ends of said front sheet.

5. The projection type image display apparatus as claimed in claim 4, wherein a plurality of said coupling members are disposed at each of the right and left ends of said front sheet.

6. The projection type image display apparatus as claimed in claim 1, wherein a hole is bored in each of the hanging members disposed in the central part and on the right and left sides of said screen, and said screen frame has bosses, each of which is disposed in a position matching each of the holes bored in said hanging members and to be inserted into the hole.

7. The projection type image display apparatus as claimed in claim 6, wherein the size of the hole in the horizontal direction in each of the hanging members positioned on the right and left sides of said screen is greater than the size of the hole in the horizontal direction in the hanging member positioned in the central part of said screen.

8. The projection type image display apparatus as claimed in claim 7, wherein the holes in the hanging members positioned on the right and left sides of said screen are elliptic-shaped and the hole in the hanging member positioned in the central part of in the hanging member positioned in the central part of said screen is round.

9. A projection type image display apparatus comprising:

a screen on which an enlarged image is to be projected,

a screen frame which is fixed to a housing of said display apparatus, and

a plurality of hanging members to be fitted to said screen frame, disposed at least at a center part and on right and left sides of the upper side of said screen, wherein;

a hole is bored in each of said plurality hanging members, and said screen frame has bosses, each of which matches each of the holes in the hanging members and is to be inserted into the hole, and

the size of the hole in the horizontal direction in each of the hanging members positioned on the right and left sides of said screen is greater than the size of the hole in the horizontal direction in the hanging member positioned in the central part of said screen.

10. The projection type image display apparatus as claimed in claim 9, wherein said screen comprises a front sheet for diffusing lights of the image at least in the horizontal direction and a Fresnel lens sheet which is arranged on the light incidence side of the front sheet and in which a Fresnel lens is formed,

said plurality of hanging members are disposed on the upper side of said front sheet, a supporting member whose section is L-shaped is disposed on the lower side of said front sheet, said Fresnel lens sheet is mounted on said supporting member, and a tension is given by the weight of the Fresnel lens sheet in the vertical direction of said front sheet.

11. The projection type image display apparatus as claimed in claim 10, wherein coupling members to be coupled with tensioning members for giving tension in the horizontal direction of said front sheet are disposed at the right and left ends of said front sheet.

12. The projection type image display apparatus as claimed in claim 11, wherein a plurality of said supporting members are disposed, and each supporting member is arranged in a position matching one or another of said hanging members on the lower side of said front sheet.