Optical scanning apparatus

• US 5,774,248 A
• Filed: 08/25/1997
• Issued: 06/30/1998
• Est. Priority Date: 07/08/1993
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Komatsu, Teruo
• Primary Examiner(s): Dzierzynski, Paul M.
• Assistant Examiner(s): Schuberg, Darren E.
• Application Number:
  US08/917,279
• Time in Patent Office: 309 Days
• Field of Search: 372/23, 359/196, 359/209, 359/214, 359/216, 359/217, 359/218, 359/219, 359/204, 359/201, 347/234, 347/245, 347/233, 347/242, 347/134, 347/241, 347/237, 347/243, 347/244
• US Class Current: 359/204.1
• CPC Class Codes: G02B 26/123 Multibeam scanners, e.g. using multiple light sources or beam splitters

Abstract

An optical scanning apparatus can record image information in a plurality of resolutions by changing the pitch (scanning interval) of light beams in a direction orthogonal to the scanning direction. In the apparatus, a plurality of light beams emitted from a light-source unit having a plurality of light-emitting portions are guided to a deflector via an optical system, and are deflected and reflected by the deflector. The light beams are then guided to a surface to be scanned via an imaging unit, so that the surface is simutaneously scanned by the plurality of light beams. At that time, an angle θ between a first line connecting imaged positions of the plurality of light beams on the surface and a second line obtained by the scanning line of the light beams in the scanning direction on the surface, can be changed by an angle adjusting unit.

Claims

1. An optical scanning apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

scanning means for scanning a predetermined surface in a scanning direction, said scanning means scanning the predetermined surface with the plural light beams from said light-source means by deflecting the plural light beams;

optical means disposed in an optical path between said light-source means and said scanning means; and

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light beams are arranged on the predetermined surface and the scanning direction in which the plural light beams are scanned on the predetermined surface, the angle θ

being changed automatically in correspondence to the selected resolution.

2. An apparatus according to claim 1, wherein said angle adjusting means rotates said light-source means.

3. An apparatus according to claim 1, wherein said angle adjusting means rotates said optical means.

4. An apparatus according to claim 1, wherein said angle adjusting means moves said optical means.

5. An apparatus according to claim 1, wherein said plural light beams are modulated with image information at the selected resolution.

6. An apparatus according to claim 1, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

7. An apparatus according to claim 1, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

8. An optical scanning apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light emitting portions which emit respective ones of plural light beams;

scanning means for scanning a predetermined surface in a scanning direction, said scanning means scanning the predetermined surface with the plural light beams from said light-source means by deflecting the plural light beams; and

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light beams are arranged on the predetermined surface and the scanning direction in which the plural light beams are scanned on the predetermined surface, the angle θ

being changed automatically in correspondence to the selected resolution.

9. An apparatus according to claim 8, wherein said plural light beams are modulated with image information at the selected resolution.

10. An apparatus according to claim 8, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

11. An apparatus according to claim 8, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

12. An optical scanning apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

rotation means for automatically rotating said light-source means in correspondence to the selected resolution; and

deflection means for deflecting the plural light beams from said light-source means.

13. An apparatus according to claim 12, wherein said plural light beams are modulated with image information at the selected resolution.

14. An apparatus according to claim 12, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

15. An apparatus according to claim 12, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

16. An optical scanning apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

optical means including a plurality of light-emitting portions which emit respective ones of plural light beams;

rotation means for automatically rotating at least a part of said optical means in correspondence to the selected resolution; and

deflection means for deflecting the plural light beams from said optical means.

17. An apparatus according to claim 16, wherein said plural light beams are modulated with image information at the selected resolution.

18. An apparatus according to claim 16, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

19. An apparatus according to claim 16, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

20. An optical scanning apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

emission control means for controlling the plurality of light-emitting portions;

scanning means for scanning a predetermined surface in a scanning direction, said scanning means scanning the predetermined surface with the plural light beams from said light-source means by deflecting the plural light beams;

optical means disposed in an optical path between said light-source means and said scanning means;

synchronization detection means for detecting the timing of the start of light beam scanning on the predetermined surface;

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light beams are arranged on the predetermined surface and the scanning direction in which the plural light beams are scanned on the predetermined surface, the angle θ

being changed automatically in correspondence to the selected resolution;

position detection means for detecting position information relating to a position adjusted by said angle adjusting means; and

control means for controlling said emission control means by linking said synchronization detection means with said position detection means.

21. An apparatus according to claim 20, wherein said angle adjusting means rotates said light-source means, and wherein said position detection means detects angular position after the rotation.

22. An apparatus according to claim 20, wherein said angle adjusting means rotates said optical means, and wherein said position detection means detects angular position after the rotation.

23. An apparatus according to claim 20, wherein said angle adjusting means moves said optical means, and wherein said position detection means detects a position after the movement.

24. An apparatus according to claim 20, wherein said plural light beams are modulated with image information at the selected resolution.

25. An apparatus according to claim 20, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

26. An apparatus according to claim 20, wherein spot size of the scanned plural beams is set in, correspondence to the selected resolution.

53. An apparatus according to claim 20, wherein said angle adjusting means moves said optical means, and wherein said position detection means detects a position after the movement.

27. An optical scanning apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

emission control means for controlling the plurality of light-emitting portions;

scanning means for scanning a predetermined surface in a scanning direction, said scanning means scanning the predetermined surface with the plural light beams from said light-source means by deflecting the plural light beams;

synchronization detection means for detecting the timing of the start of the scanning on the predetermined surface; and

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light beams are arranged on the predetermined surface and the scanning direction in which the plural light beams are scanned on the predetermined surface, the angle θ

being changed automatically in correspondence to the selected resolution.

28. An apparatus according to claim 27, wherein said plural light beams are modulated with image information at the selected resolution.

29. An apparatus according to claim 27, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

30. An apparatus according to claim 27, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

31. A laser-beam printing apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

a recording medium;

scanning means for scanning said recording medium in a scanning direction, said scanning means scanning said recording medium with the plural light beams from said light-source means by deflecting the plural light beams;

optical means disposed in an optical path between said light-source means and said scanning means; and

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light-beams are arranged on said recording medium and the scanning direction in which the plural light beams are scanned on said recording medium, the angle θ

being changed automatically in correspondence to the selected resolution.

32. An apparatus according to claim 31, wherein said angle adjusting means rotates said light-source means.

33. An apparatus according to claim 31, wherein said angle adjusting means rotates said optical means.

34. An apparatus according to claim 31, wherein said angle adjusting means moves said optical means.

35. An apparatus according to claim 31, wherein said plural light beams are modulated with image information at the selected resolution.

36. An apparatus according to claim 31, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

37. An apparatus according to claim 31, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

38. A laser-beam printing apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

a recording medium;

scanning means for scanning said recording medium in a scanning direction, said scanning means scanning said recording medium with the plural light beams from said light-source means by deflecting the plural light beams; and

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light beams are arranged on said recording medium and the scanning direction in which the plural light beams are scanned on said recording medium, the angle θ

being changed automatically in correspondence to the selected resolution.

39. An apparatus according to claim 38, wherein said plural light beams are modulated with image information at the selected resolution.

40. An apparatus according to claim 38, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

41. An apparatus according to claim 38, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

42. A laser-beam printing apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

a recording medium;

rotation means for automatically rotating said light-source means in correspondence to the selected resolution; and

deflection means for deflecting the plural light beams from said light-source means toward said recording medium.

43. An apparatus according to claim 42, wherein said plural light beams are modulated with image information at the selected resolution.

44. An apparatus according to claim 42, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

45. An apparatus according to claim 42, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

46. A laser-beam printing apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

optical means including a plurality of light-emitting portions which emit respective ones of plural light beams;

a recording medium;

rotation means for automatically rotating at least a part of said optical means in correspondence to the selected resolution; and

deflection means for deflecting the plural light beams from said optical means toward said recording medium.

47. An apparatus according to claim 46, wherein said plural light beams are modulated with image information at the selected resolution.

48. An apparatus according to claim 46, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

49. An apparatus according to claim 46, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

50. A laser-beam printing apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

emission control means for controlling the plurality of light-emitting portions;

a recording medium;

scanning means for scanning said recording medium in a scanning direction, said scanning means scanning said recording medium with the plural light beams from said light-source means by deflecting the plural light beams;

optical means disposed in an optical path between said light-source means and said scanning means;

synchronization detection means for detecting the timing of the start of light beam scanning on said recording medium;

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light beams are arranged on said recording medium and the scanning direction in which the plural light beams are scanned on said recording medium, the angle θ

being changed automatically in correspondence to the selected resolution;

position detection means for detecting position information relating to a position adjusted by said angle adjusting means; and

control means for controlling said emission control means by linking said synchronization detection means with said position detection means.

51. An apparatus according to claim 50, wherein said angle adjusting means rotates said light-source means, and wherein said position detection means detects angular position after the rotation.

52. An apparatus according to claim 50, wherein said angle adjusting means rotates said optical means, and wherein said position detection means detects angular position after the rotation.

54. An apparatus according to claim 50, wherein said plural light beams are modulated with image information at the selected resolution.

55. An apparatus according to claim 50, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

56. An apparatus according to claim 50, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

58. An apparatus according to claim 52, wherein said plural light beams are modulated with image information at the selected resolution.

57. A laser-beam printing apparatus for scanning plural light beams modulated with image information in a selectable one of at least two different image resolutions, said optical scanning apparatus comprising:

light-source means including a plurality of light-emitting portions which emit respective ones of plural light beams;

emission control means for controlling the plurality of light-emitting portions;

a recording medium;

scanning means for scanning said recording medium in a scanning direction, said scanning means scanning said recording medium with the plural light beams from said light-source means by deflecting the plural light beams;

synchronization detection means for detecting the timing of the start of the scanning on said recording medium; and

angle adjusting means for automatically changing an angle θ

between a direction in which images of the plural light means are arranged on said recording medium and the scanning direction in which the plural light beams are scanned on said recording medium, the angle θ

being changed automatically in correspondence to the selected resolution.

59. An apparatus according to claim 57, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

60. An apparatus according to claim 57, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

61. A scanning method for scanning a predetermined surface with a plurality of light beams modulated with image information in a selectable one of at least two different image resolutions, said method comprising the steps of:

scanning the predetermined surface in a scanning direction with the plurality of light beams by deflecting the plurality of light beams; and

automatically changing an angle θ

between a direction in which images of the plurality of light beams are arranged on the predetermined surface and the scanning direction in which the plurality of light beams are scanned on the predetermined surface, the angle θ

being changed automatically in correspondence to the selected resolution.

62. A method according to claim 61, further comprising the step of modulating said plurality of light beams with image information at the selected resolution.

63. A method according to claim 61, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

64. A method according to claim 61, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

65. A scanning method for scanning a predetermined surface with a plurality of light beams modulated with image information in a selectable one of at least two different image resolutions, said method comprising the steps of:

scanning the predetermined surface with a plurality of light beams emitted from a light-source unit by deflecting the plurality of light beams; and

automatically rotating said light-source unit in correspondence to the selected resolution.

66. A method according to claim 65, further comprising the step of modulating said plurality of light beams with image information at the selected resolution.

67. A method according to claim 65, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

68. A method according to claim 65, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

69. A scanning method for scanning a predetermined surface with a plurality of light beams modulated with image information in a selectable one of at least two different image resolutions, said method comprising the steps of:

guiding the plurality of light beams to a deflector via an optical system;

scanning the predetermined surface with the plurality of light beams by deflecting the plurality of light beams with the deflector;

automatically rotating a part of the optical system in correspondence to the selected resolution.

70. A method according to claim 69, further comprising the step of modulating said plurality of light beams with image information at the selected resolution.

71. A method according to claim 69, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

72. A method according to claim 69, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.

73. A scanning method for scanning a predetermined surface with a plurality of light beams modulated with image information in a selectable one of at least two different image resolutions, said method comprising the steps of:

scanning the predetermined surface in a scanning direction with the plurality of light beams by deflecting the plurality of light beams;

controlling the emission of the plurality of light beams;

detecting the timing of the start of the scanning of the predetermined surface; and

automatically changing an angle θ

between a direction in which images of the plurality of light beams are arranged on the predetermined surface and the scanning direction in which the plurality of light beams are scanned on the predetermined surface, the angle θ

being changed automatically in correspondence to the selected resolution.

74. A method according to claim 73, further comprising the step of modulating said plurality of light beams with image information at the selected resolution.

75. A method according to claim 73, wherein the plural light beams are deflected at a speed corresponding to the selected resolution.

76. A method according to claim 73, wherein spot size of the scanned plural beams is set in correspondence to the selected resolution.