Projector

• US 5,223,869 A
• Filed: 02/20/1991
• Issued: 06/29/1993
• Est. Priority Date: 02/20/1990
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yanagi, Haruyuki
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Dowling, William C.
• Application Number:
  US07/658,047
• Time in Patent Office: 860 Days
• Field of Search: 353/77, 353/78, 353/79, 353/94, 353/99, 353/98, 353/73, 353/37, 353/31, 353/30, 353/74, 353/38, 358/60, 358/64, 358/231, 358/237
• US Class Current: 353/78
• CPC Class Codes: G03B 21/10 Projectors with built-in or built-on screen
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor

Abstract

A projector suitable for a rear projection type receiver is disclosed. The projector has a device for generating an image and an image projecting device for projecting the image to a screen. The image projecting device includes a projection lens system and a reflector. The projection lens system directs the light flux indicative of the image from the image generating device toward the reflector so as to be away from the screen. The reflector bends the light flux and directs the light flux from the reflector to the screen along a predetermined path. The image generating device and the projection lens system are arranged on the side of the predetermined path along the path.

Claims

1. A projector comprising:

means for generating an image; and

means for projecting the image to a screen, said projecting means having a projection lens system, a first reflector and a second reflector, where said projection lens system directs a light beam indicative of the image from said generating means to said first reflector in a direction away from said screen, and said first reflector reflects the light beam incident thereon so that the light beam is folded thereat to be directed to said second reflector, and said second reflector reflects the light beam incident thereon so as to be folded thereat and to be directed to said screen such that an optical axis between said projection lens system and said first reflector and an optical axis between said second reflector and said screen do not intersect each other and such that the light beam is caused to be obliquely incident on said screen and a marginal portion of the light beam to be incident on said screen at the side opposed to the arrangement of said generating means and said projection lens system is caused to be incident on the screen with an incident angle of 0°

to 5°

, and wherein said generating means and said projection lens system are successively arranged from said screen so as to be disposed adjacent to the light beam from said second reflector to said screen.

2. A projector according to claim 1, wherein the projection lens system is obliquely arranged together with the generating means in a manner such that an angle between the optical axis of the projection lens system and an incident angle of the light flux to the screen lies within a range from 0°

to 10°

.

3. A projector according to claim 1, wherein the generating means has:

a first generator to form a red image;

a second generator to form a blue image; and

a third image to form a green image.

4. A projector according to claim 3, wherein the projection lens system has:

a first projection lens to project the image of the first generator;

a second projection lens to project an image of the second generator; and

a third projection lens to project an image of the third generator.

5. A projector according to claim 3, wherein the projection lens system has a single lens assembly to project the images of the first, second, and third generators.

6. A projector according to claim 1, wherein the generating means and the projection lens system are integratedly constructed.

7. A projector according to claim 1, wherein said first reflector and said second reflector are mutually connected.

8. A projector according to claim 3, wherein said generating means has a CRT.

9. A projector according to claim 4, wherein said generating means has a CRT.

10. A projector according to claim 5, wherein said generating means has a CRT.

11. A projector according to claim 3, wherein said generating means has a liquid crystal display.

12. A projector according to claim 4, wherein said generating means has a liquid crystal display.

13. A projector according to claim 5, wherein said generating means has a liquid crystal display.

55. A projector according to claim 11, wherein the projection lens system is obliquely arranged together with the generator in a manner such that an angle between the optical axis of the injection lens system and an incident angle of the light flux to the screen lies within a range from 0°

to 10°

.

56. A projector according to claim 11, wherein the projection lens system and the generator are integratedly constructed.

14. A projector comprising:

means for generating an image; and

means for projecting said image to a screen;

wherein said projecting means has a projection lens system and reflectors;

wherein said projection lens system directs a light beam indicative of the image from said generating means to said reflectors in a direction away from said screen, and said reflectors reflect the light beam incident thereon so that the light beam is folded thereat and to be directed to said screen such that an optical axis between said projection lens system and each of said reflectors and an optical axis between another reflector and said screen do not intersect each other;

wherein said reflectors are arranged such that when tracing the light path in order from said screen, said reflectors and said projection lens system, the light path between any of said reflectors and said projection lens system is directed toward said screen;

and wherein said reflectors direct said light beam to said screen such that the light beam is caused to be obliquely incident on said screen and a marginal portion of the light beam to be incident on said screen at the side opposed to the arrangement of said generating means and said projection lens system is caused to be incident on said screen with an incident angle of 0°

to 5°

.

15. A projector comprising:

a screen;

means for projecting an image; and

means for projecting said image to said screen, said projecting means having a projection lens system, a first reflector and a second reflector, wherein said projection lens system directs a light beam indicative of the image from said generating means to said first reflector in a direction away from said screen, and said first reflector reflects the light beam incident thereon so that the light beam is folded thereat to be directed to said second reflector, and said second reflector reflects the light beam incident thereon so as to be folded thereat and to be directed to said screen such that an optical axis between said projection lens system and said first reflector and said screen do not intersect each other, and said second reflector bends the light flux so that the light flux obliquely enters the screen, and said generating means and said projection lens system are successively arranged from said screen so as to be disposed adjacent to the light beam from said second reflector to said screen, and wherein the screen has an eccentric Fresnel lens sheet and said sheet deflects the light flux in the direction perpendicular to the sheet and also converges the light flux.

16. A projector according to claim 15, wherein the first and second mirrors are connected.

17. A projector according to claim 15, wherein the projection lens system is obliquely arranged together with the generator in a manner such that an angle between the optical axis of the projection lens system and an incident angle of the light flux to the screen lies within a range from 0°

to 10°

.

18. A projector according to claim 15, wherein the projection lens system and the generator are integratedly constructed.

19. A projector according to claim 15, wherein said generating means has:

a first generator to form a red image;

a second generator to form a blue image; and

a third generator to form a green image.

20. A projector according to claim 19, wherein the projection lens system has:

a first projection lens to project the image of the first generator;

a second projection lens to project the image of the second generator; and

a third projection lens to project the image of the third generator.

21. A projector according to claim 19, wherein the projection lens system has a single lens assembly to project the images of the first, second, and third generators.

22. A projector according to any one of claims 19 to 21, wherein said generating means has a CRT.

23. A projector according to any one of claims 19 to 21, wherein said generating means has a liquid crystal display.

24. A projector according to claim 15, wherein said generating means and the projection lens system are arranged at a lower position of the light beam.

25. A projector according to claim 15, wherein said generating means and the projection lens system are arranged at an upper or side position of the light beam.

26. A projector comprising:

a screen;

means for generating an image; and

means for projecting said image to said screen, said projecting means having a projection lens system, a first reflector and a second reflector, wherein said projection lens system directs a light beam indicative of the image from said generating means to said first reflector in a direction away from said screen, and said first reflector reflects the light beam incident thereon so that the light beam is folded thereat to be directed to said second reflector, and said second reflector reflects the light beam incident thereon so as to be folded thereat and to be directed to said screen such that an optical axis between said projection lens system and said first reflector and said screen do not intersect each other and to be directed to said screen such that the light beam is caused to be obliquely incident on said screen and a marginal portion of the light beam to be incident on said screen at the side opposed to the arrangement of said generating means and said projection lens system is caused to be incident on the screen with an incident angle of 0°

to 5°

, and wherein said generating means and said projection lens system are successively arranged from said screen so as to be disposed adjacent to the light beam from said second reflector to said screen.

27. A projector comprising:

means for generating an image; and

means for projecting having a projection lens system, a first reflector and a second reflector, wherein said projection lens system directs a light beam indicative of the image from said generating means to said first reflector in a direction away from said screen, and said first reflector reflects the light beam incident thereon so that the light beam is folded thereat to be directed to said second reflector, and said second reflector reflects the light beam incident thereon so as to be folded thereat and to be directed to said screen such that an optical axis between said projection lens system and said first reflector and an optical axis between said second reflector and said screen do not intersect each other and to be directed to said screen such that the light beam is caused to be obliquely incident on said screen and a marginal portion of the light beam to be incident on said screen at the side opposed to the arrangement of said generating means and said projection lens system is caused to be incident on the screen with an incident angle of 0°

to 5°

, and wherein said first reflector and said second reflector are arranged such that when tracing the light path in order from said screen, said second reflector, said first reflector and said projection lens system, the light path between said first reflector and said projection lens system is directed toward said screen.

29. A projector according to claim 27, wherein the projection lens system is obliquely arranged together with the generating means in a manner such that an angle between the optical axis of the projection lens system and an incident angle of the light flux to the screen lies within a range from 0°

to 10°

.

30. A projector according to claim 27, wherein the generating means has:

a first generator to form a red image;

a second generator to form a blue image; and

a third generator to form a green image.

31. A projector according to claim 30, wherein the projection lens system has:

a first projection lens to project the image of the first generator;

a second projection lens to project an image of the second generator; and

a third projection lens to project an image of the third generator.

32. A projector according to claim 30, wherein the projection lens system has a single lens assembly to project the images of the first, second and third generators.

33. A projector according to claim 27, wherein the generating means and the projection lens system are integratedly constructed.

34. A projector according to claim 27, wherein said first reflector and said second reflector are mutually connected.

35. A projector according to claim 30, wherein said generating means has a CRT.

36. A projector according to claim 31, wherein said generating means has a CRT.

37. A projector according to claim 32, wherein said generating means has a CRT.

38. A projector according to claim 30, wherein said generating means has a liquid crystal display.

39. A projector according to claim 31, wherein said generating means has a liquid crystal display.

40. A projector according to claim 32, wherein said generating means has a liquid crystal display.

28. A projector comprising:

means for generating an image; and

means for projecting having a projection lens system, a first reflector and a second reflector, wherein said projection lens system directs a light beam indicative of the image from said generating means to said first reflector in a direction away from said screen and said lens system is obliquely arranged together with the generating means in a manner such that an angle between the optical axis of the projection lens system and an incident angle of the light flux to the screen lies within a range from 0°

to 10°

, and said first reflector reflects the light beam incident thereon so that the light beam is folded thereat to be directed to said second reflector, and said second reflector reflects the light beam incident thereon so as to be folded thereat and to be directed to said screen such that an optical axis between said projection lens system and said first reflector and an optical axis between said second reflector and said screen do not intersect each other and said second reflector reflects the light beam incident thereon so as to be folded and be obliquely incident on said screen, and wherein said first reflector and said second reflector are arranged such that when tracing the light path in order from said screen, said second reflector, said first reflector and said projection lens system, the light path between said first reflector and said projection lens system is directed toward said screen.

41. A projector comprising:

a screen;

means for generating an imaged; and

means for projecting the image to a screen, said projecting means having a projection lens system, a first reflector and a second reflector, wherein said projection lens system directs a light beam indicative of the image from said generating means to said first reflector in a direction away from said screen, and said first reflector reflects the light beam incident thereon so that the light beam is folded thereat to be directed to said second reflector, and said second reflector reflects the light beam incident thereon so as to be folded thereat and to be directed to said screen such that an optical axis between said projection lens system and said first reflector and an optical axis between said second reflector and said screen do not intersect each other, and said second reflector directs the light beam to said screen such that the light beam is caused to obliquely incident on said screen and a marginal portion of the light beam to be incident on said screen at the side opposed to the arrangement of said generating means and said projection lens system is caused to be incident on the screen with an incident angle of 0°

to 5°

, and wherein said first reflector and said second reflector are arranged such that when tracing the light path in order from said screen, said second reflector, said first reflector and said projection lens system, the light path between said first reflector and said projection lens system is directed toward said screen.

42. A projector according to claim 41, wherein the projection lens system is obliquely arranged together with the generating means in a manner such that an angle between the optical axis of the projection lens system and an incident angle of the light flux to the screen lies within a range of 0°

to 10°

.

43. A projector according to claim 41, wherein the generating means has:

a first generator to form a red image;

a second generator to form a blue image; and

a third generator to form a green image.

44. A projector according to claim 43, wherein the projection lens system has:

a first projection lens to project the image of the first generator;

a second projection lens to project an image of the second generator; and

a third projection lens to project an image of the third generator.

45. A projector according to claim 43, wherein the projection lens system has a single lens assembly to project the images of the first, second and third generators.

46. A projector according to claim 41, wherein the generating means and the projection lens system are integratedly constructed.

47. A projector according to claim 43, wherein the generating means has a CRT.

48. A projector according to claim 44, wherein said generating means has a CRT.

49. A projector according to claim 45, wherein said generating means has a CRT.

50. A projector according to claim 43, wherein said generating means has a liquid crystal display.

51. A projector according to claim 44, wherein said generating means has a liquid crystal display.

52. A projector according to claim 45, wherein said generating means has a liquid crystal display.

53. A projector according to claim 41, wherein said generating means and said projection lens system are disposed under the light beam between said second reflector and said screen.

54. A projector according to claim 41, wherein said generating means and said projection lens system are disposed under the light beam between said second reflector and said screen, or laterally to said light beam.

57. A projector comprising:

means for generating an image; and

means for projecting said image to a screen;

wherein said projecting means has a projection lens system and reflectors;

wherein said projection lens system directs a light beam indicative of the image from said generating means to said reflectors in a direction away from said screen, and said reflectors reflect the light beam incident thereon so that the light beam is folded thereat and to be directed to said screen such that an optical axis between said projection lens system and each of said reflectors and an optical axis between another reflector and said screen do not intersect each other;

wherein said generating means and said projection lens system are successively arranged from said screen so as to be disposed adjacent to the light beam from said reflectors to said screen;

and wherein said reflectors direct said light beam to said screen such that the light beam is caused to be obliquely incident on said screen and a marginal portion of the light beam to be incident on said screen at the side opposed to the arrangement of said generating means and said projection lens system is caused to be incident on said screen with an incident angle of 0°

to 5°

.