Optical apparatus

• US 6,023,589 A
• Filed: 11/04/1998
• Issued: 02/08/2000
• Est. Priority Date: 11/11/1997
• Status: Expired due to Term

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Ohta, Seiya
• Primary Examiner(s): PERKEY, WILLIAM B
• Application Number:
  US09/185,951
• Time in Patent Office: 461 Days
• Field of Search: 396/97, 396/79, 396/80, 396/81, 359/820, 359/694, 359/696, 359/697, 359/698, 348/345, 348/347
• US Class Current: 396/80
• CPC Class Codes: G02B 7/102 controlled by a microcomputer cameras with interchangeable lenses G03B17/14

Abstract

An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, includes a lens driving mechanism which drives the moving lens group, a control circuit which drives and controls the lens driving mechanism on the basis of control information provided for driving and controlling the moving lens group, and a temperature and/or humidity detecting sensor for detecting information on temperature and/or humidity, wherein the control circuit computes a correction amount by which a driving limit of the moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to a temperature and/or humidity detection output of the temperature and/or humidity detecting sensor, and drives and controls the lens driving mechanism on the basis of the correction amount and the control information, so that the object image can be formed on the image forming plane of the optical system without shifting due to variations of temperature and/or variations of humidity.

Claims

1. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said lens driving mechanism on the basis of control information provided for driving and controlling said moving lens group; and

temperature detecting means for detecting information on temperature,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to a temperature detection output of said temperature detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature.

5. An apparatus according to claim 1, wherein the control information includes position data of said moving lens group obtained at a reference temperature and temperature coefficient data for correcting the position data of said moving lens group according to variations of temperature indicated by the temperature detection output of said temperature detecting means, and wherein said control circuit computes the correction amount by which the driving limit of said moving lens group toward the nearest-distance end or infinity-distance end for focus adjustment is variable, according to the variations of temperature indicated by the temperature detection output of said temperature detecting means and the temperature coefficient data, and drives and controls said lens driving mechanism on the basis of the correction amount and the position data of said moving lens group.

6. An apparatus according to claim 1, wherein said optical system is a zoom lens.

7. An apparatus according to claim 1, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

8. An apparatus according to claim 1, wherein at least a part of said moving lens group of said optical system is a plastic lens.

2. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said moving lens group;

a storage circuit which stores therein control information provided for driving and controlling said moving lens group;

temperature detecting means for detecting information on temperature; and

focus detecting means for detecting a focusing state of said optical system,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to a temperature detection output of said temperature detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information by using an output of said focus detecting means, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature.

9. An apparatus according to claim 2, wherein said optical system is a zoom lens.

12. An apparatus according to claim 2, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

15. An apparatus according to claim 2, wherein at least a part of said moving lens group of said optical system is a plastic lens.

3. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said lens driving mechanism on the basis of control information provided for driving and controlling said moving lens group; and

temperature detecting means for detecting information on temperature,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to variations of temperature indicated by a temperature detection output of said temperature detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature.

10. An apparatus according to claim 3, wherein said optical system is a zoom lens.

13. An apparatus according to claim 3, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

16. An apparatus according to claim 3, wherein at least a part of said moving lens group of said optical system is a plastic lens.

4. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said moving lens group;

a storage circuit which stores therein control information provided for driving and controlling said moving lens group,

temperature detecting means for detecting information on temperature; and

focus detecting means for detecting a focusing state of said optical system,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to variations of temperature indicated by a temperature detection output of said temperature detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information by using an output of said focus detecting means, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature.

11. An apparatus according to claim 4, wherein said optical system is a zoom lens.

14. An apparatus according to claim 4, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

17. An apparatus according to claim 4, wherein at least a part of said moving lens group of said optical system is a plastic lens.

18. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said lens driving mechanism on the basis of control information provided for driving and controlling said moving lens group; and

humidity detecting means for detecting information on humidity,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of humidity.

22. An apparatus according to claim 18, wherein the control information includes position data of said moving lens group obtained at a reference humidity and humidity coefficient data for correcting the position data of said moving lens group according to variations of humidity indicated by the humidity detection output of said humidity detecting means, and wherein said control circuit computes the correction amount by which the driving limit of said moving lens group toward the nearest-distance end or infinity-distance end for focus adjustment is variable, according to the variations of humidity indicated by the humidity detection output of said humidity detecting means and the humidity coefficient data, and drives and controls said lens driving mechanism on the basis of the correction amount and the position data of said moving lens group.

23. An apparatus according to claim 18, wherein said optical system is a zoom lens.

24. An apparatus according to claim 18, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

25. An apparatus according to claim 18, wherein at least a part of said moving lens group of said optical system is a plastic lens.

19. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said moving lens group;

a storage circuit which stores therein control information provided for driving and controlling said moving lens group;

humidity detecting means for detecting information on humidity; and

focus detecting means for detecting a focusing state of said optical system,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information by using an output of said focus detecting means, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of humidity.

26. An apparatus according to claim 19, wherein said optical system is a zoom lens.

29. An apparatus according to claim 19, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

32. An apparatus according to claim 19, wherein at least a part of said moving lens group of said optical system is a plastic lens.

20. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said lens driving mechanism on the basis of control information provided for driving and controlling said moving lens group; and

humidity detecting means for detecting information on humidity,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to variations of humidity indicated by a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of humidity.

27. An apparatus according to claim 20, wherein said optical system is a zoom lens.

30. An apparatus according to claim 20, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

33. An apparatus according to claim 20, wherein at least a part of said moving lens group of said optical system is a plastic lens.

21. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said moving lens group;

a storage circuit which stores therein control information provided for driving and controlling said moving lens group;

humidity detecting means for detecting information on humidity; and

focus detecting means for detecting a focusing state of said optical system,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to variations of humidity indicated by a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information by using an output of said focus detecting means, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of humidity.

28. An apparatus according to claim 21, wherein said optical system is a zoom lens.

31. An apparatus according to claim 21, wherein said optical system includes first position detecting means for detecting a position of said moving lens group for focus adjustment, a moving lens group for variable magnification, and second position detecting means for detecting a position of said moving lens group for variable magnification.

34. An apparatus according to claim 21, wherein at least a part of said moving lens group of said optical system is a plastic lens.

35. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said lens driving mechanism on the basis of control information provided for driving and controlling said moving lens group;

temperature detecting means for detecting information on temperature; and

humidity detecting means for detecting information on humidity,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to a temperature detection output of said temperature detecting means and a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature and variations of humidity.

39. An apparatus according to claim 35, wherein the control information includes position data of said moving lens group obtained at a reference temperature and a reference humidity, temperature coefficient data for correcting the position data of said moving lens group according to variations of temperature indicated by the temperature detection output of said temperature detecting means and humidity coefficient data for correcting the position data of said moving lens group according to variations of humidity indicated by the humidity detection output of said humidity detecting means, and wherein said control circuit computes the correction amount by which the driving limit of said moving lens group toward the nearest-distance end or infinity-distance end for focus adjustment is variable, according to the variations of temperature indicated by the temperature detection output of said temperature detecting means, the temperature coefficient data, the variations of humidity indicated by the humidity detection output of said humidity detecting means and the humidity coefficient data, and drives and controls said lens driving mechanism on the basis of the correction amount and the position data of said moving lens group.

36. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said moving lens group;

a storage circuit which stores therein control information provided for driving and controlling said moving lens group;

temperature detecting means for detecting information on temperature;

humidity detecting means for detecting information on humidity; and

focus detecting means for detecting a focusing state of said optical system,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to a temperature detection output of said temperature detecting means and a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information by using an output of said focus detecting means, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature and variations of humidity.

40. An apparatus according to claim 36, wherein the control information includes position data of said moving lens group obtained at a reference temperature and a reference humidity, temperature coefficient data for correcting the position data of said moving lens group according to variations of temperature indicated by the temperature detection output of said temperature detecting means and humidity coefficient data for correcting the position data of said moving lens group according to variations of humidity indicated by the humidity detection output of said humidity detecting means, and wherein said control circuit computes the correction amount by which the driving limit of said moving lens group toward the nearest-distance end or infinity-distance end for focus adjustment is variable, according to the variations of temperature indicated by the temperature detection output of said temperature detecting means, the temperature coefficient data, the variations of humidity indicated by the humidity detection output of said humidity detecting means and the humidity coefficient data, and drives and controls said lens driving mechanism on the basis of the correction amount and the position data of said moving lens group.

37. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said lens driving mechanism on the basis of control information provided for driving and controlling said moving lens group;

temperature detecting means for detecting information on temperature; and

humidity detecting means for detecting information on humidity,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to variations of temperature indicated by a temperature detection output of said temperature detecting means and variations of humidity indicated by a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature and variations of humidity.

41. An apparatus according to claim 37, wherein the control information includes position data of said moving lens group obtained at a reference temperature and a reference humidity, temperature coefficient data for correcting the position data of said moving lens group according to variations of temperature indicated by the temperature detection output of said temperature detecting means and humidity coefficient data for correcting the position data of said moving lens group according to variations of humidity indicated by the humidity detection output of said humidity detecting means, and wherein said control circuit computes the correction amount by which the driving limit of said moving lens group toward the nearest-distance end or infinity-distance end for focus adjustment is variable, according to the variations of temperature indicated by the temperature detection output of said temperature detecting means, the temperature coefficient data, the variations of humidity indicated by the humidity detection output of said humidity detecting means and the humidity coefficient data, and drives and controls said lens driving mechanism on the basis of the correction amount and the position data of said moving lens group.

38. An optical apparatus for forming an object image on an image forming plane by using an optical system including a moving lens group for focus adjustment, said optical apparatus comprising:

a lens driving mechanism which drives said moving lens group;

a control circuit which drives and controls said moving lens group;

a storage circuit which stores therein control information provided for driving and controlling said moving lens group;

temperature detecting means for detecting information on temperature;

humidity detecting means for detecting information on humidity; and

focus detecting means for detecting a focusing state of said optical system,

wherein said control circuit computes a correction amount by which a driving limit of said moving lens group toward a nearest-distance end or infinity-distance end for focus adjustment is variable, according to variations of temperature indicated by a temperature detection output of said temperature detecting means and variations of humidity indicated by a humidity detection output of said humidity detecting means, and drives and controls said lens driving mechanism on the basis of the correction amount and the control information by using an output of said focus detecting means, so that the object image can be formed on the image forming plane of said optical system without shifting due to variations of temperature and variations of humidity.

42. An apparatus according to claim 38, wherein the control information includes position data of said moving lens group obtained at a reference temperature and a reference humidity, temperature coefficient data for correcting the position data of said moving lens group according to variations of temperature indicated by the temperature detection output of said temperature detecting means and humidity coefficient data for correcting the position data of said moving lens group according to variations of humidity indicated by the humidity detection output of said humidity detecting means, and wherein said control circuit computes the correction amount by which the driving limit of said moving lens group toward the nearest-distance end or infinity-distance end for focus adjustment is variable, according to the variations of temperature indicated by the temperature detection output of said temperature detecting means, the temperature coefficient data, the variations of humidity indicated by the humidity detection output of said humidity detecting means and the humidity coefficient data, and drives and controls said lens driving mechanism on the basis of the correction amount and the position data of said moving lens group.