Lens device and optical apparatus

• US 6,115,552 A
• Filed: 06/13/1998
• Issued: 09/05/2000
• Est. Priority Date: 06/16/1997
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kaneda, Naoya
• Primary Examiner(s): ADAMS JR, RUSSELL E
• Application Number:
  US09/097,000
• Time in Patent Office: 815 Days
• Field of Search: 396/72, 396/76-79, 396/81, 396/82, 396/87, 396/101
• US Class Current: 396/82
• CPC Class Codes: G02B 7/102 controlled by a microcomputer cameras with interchangeable lenses G03B17/14

Abstract

A lens device comprises an optical system including a first lens which performs a magnification varying operation, and a second lens which is positioned rearwardly of the first lens along an optical axis and performs a focus adjusting operation, a first detecting circuit for detecting a position of the first lens and a position of the second lens, and a storage circuit which stores a positional relation between the first lens and the second lens under reference conditions, wherein a position detection by the first detecting circuit is corrected by use of deviation information if the position of the first lens and the position of the second lens detected by the first detecting circuit deviate from the positional relation stored in the storage circuit, when an in-focus state of the second lens is detected.

Claims

1. A lens device comprising:

an optical system including a first lens which performs a magnification varying operation, and a second lens which is positioned rearwardly of said first lens along an optical axis and performs a focus adjusting operation;

first detecting means for detecting a position of said first lens and a position of said second lens; and

a storage circuit which stores a positional relation between said first lens and said second lens, with said first lens being set at a predetermined position, wherein a position detection by said first detecting means is corrected by use of deviation information if the position of said lens and the position of said second lens is detected by said first detecting means deviate from the positional relation stored in said storage circuit, when an in-focus state of said second lens is detected.

2. A device according to claim 1, wherein detection of the position of at least either one of said first lens and said second lens is performed on the basis of an amount of movement of said at least either one from a reset position, said first detecting means including a reset position detecting mechanism.

3. A device according to claim 1, wherein said storage circuit has at least stored information which stores a position to be occupied by said second lens when at least said first lens is positioned at or near a wide-angle end, the position detection by said first detecting means being corrected by use of the stored information and information indicative of an actual deviation of the position of said second lens.

4. A device according to claim 1, wherein said optical system is capable of being switched between a normal photography range and a macrophotography range, correction of the position detection by said first detecting means being disabled when said optical system is set to the macrophotography range.

5. A device according to claim 1, further comprising:

operating switch means which can be externally operated,

wherein only when said operating switch means performs a particular operation, correction of the position detection by said first detecting means is executed.

6. A device according to claim 1, wherein correction of the position detection by said first detecting means is cancelled when a power source is turned off.

7. A device according to claim 1, wherein correction of the position detection by said first detecting means is cancelled when a power source is turned off.

8. A device according to claim 1, wherein said optical system uses a plastic lens.

9. A device according to claim 3, wherein said optical system uses a plastic lens.

10. A device according to claim 1, wherein the position detection by said first detecting means is corrected with a particular correction value selected from a plurality of correction values.

11. A lens device comprising:

an optical system including a first lens which performs a magnification varying operation, and a second lens which is positioned rearwardly of said first lens along an optical axis and performs a focus adjusting operation;

first detecting means for detecting a position of said first lens and a position of said second lens;

second detecting means for detecting an environmental state such as temperature or humidity; and

a storage circuit which stores a positional relation between said first lens and said second lens, with said first lens being set at a predetermined position, wherein a position detection by said first detecting means is corrected by use of deviation information and a detection result of said second detecting means if the position of said first lens and the position of said second lens detected by said first detecting means deviate from the positional relation stored in said storage circuit, when an in-focus state of said second lens is detected.

12. A device according to claim 11, wherein detection of the position of at least either one of said first lens and said second lens is performed on the basis of an amount of movement of said at least either one from a reset position, said first detecting means including a reset position detecting mechanism.

13. A device according to claim 11, wherein said storage circuit has at least stored information which stores a position to be occupied by said second lens when at least said first lens is positioned at or near a wide-angle end, the position detection by said first detecting means being corrected by use of the stored information and information indicative of an actual deviation of the position of said second lens.

14. A device according to claim 11, wherein said optical system is capable of being switched between a normal photography range and a macrophotography range, correction of the position detection by said first detecting means being disabled when said optical system is set to the macrophotography range.

15. A device according to claim 11, further comprising:

operating switch means which can be externally operated,

wherein only when said operating switch means performs a particular operation, correction of the position detection by said first detecting means is executed.

16. A device according to claim 11, wherein said optical system uses a plastic lens.

17. A device according to claim 13, wherein said optical system uses a plastic lens.

18. A device according to claim 11, wherein the position detection by said first detecting means is corrected with a particular correction value selected from a plurality of correction values.

19. An optical apparatus comprising:

an optical system including a first lens which performs a magnification varying operation, and a second lens which is positioned rearwardly of said first lens along an optical axis and performs a focus adjusting operation;

first detecting means for detecting a position of said first lens and a position of said second lens;

focus detecting means for detecting a state of focus; and

a storage circuit which stores a positional relation between said first lens and said second lens, with said first lens being set at a predetermined position, wherein a position detection by said first detecting means is corrected by use of deviation information if the position of said first lens and the position of said second lens detected by said first detecting means deviate from the positional relation stored in said storage circuit, when an in-focus state of said second lens is detected by said focus detecting means.

20. An apparatus according to claim 19, wherein detection of the position of at least either one of said first lens and said second lens is performed on the basis of an amount of movement of said at least either one from a reset position, said first detecting means including a reset position detecting mechanism.

21. An apparatus according to claim 19, wherein said storage circuit has at least stored information which stores a position to be occupied by said second lens when at least said first lens is positioned at or near a wide-angle end, the position detection by said first detecting means being corrected by use of the stored information and information indicative of an actual deviation of the position of said second lens.

22. An apparatus according to claim 19, wherein said optical system is capable of being switched between a normal photography range and a macrophotography range, correction of the position detection by said first detecting means being disabled when said optical system is set to the macrophotography range.

23. An apparatus according to claim 19, further comprising:

operating switch means which can be externally operated,

wherein only when said operating switch means performs a particular operation, correction of the position detection by said first detecting means is executed.

24. An apparatus according to claim 19, wherein correction of the position detection by said first detecting means is cancelled when a power source is turned off.

25. An apparatus according to claim 19, wherein said optical system uses a plastic lens.

26. An apparatus according to claim 21, wherein said optical system uses a plastic lens.

27. An apparatus according to claim 19, wherein the position detection by said first detecting means is corrected with a particular correction value selected from a plurality of correction values.

28. An optical apparatus comprising:

an optical system including a first lens which performs a magnification varying operation, and a second lens which is positioned rearwardly of said first lens along an optical axis and performs a focus adjusting operation;

first detecting means for detecting a position of said first lens and a position of said second lens;

second detecting means for detecting an environmental state such as temperature or humidity;

focus detecting means for detecting means for detecting a state of focus; and

a storage circuit which stores a positional relation between said first lens and said second lens, with said first lens being set at a predetermined position, wherein a position detection by said first detecting means is corrected by use of deviation information and a detection result of said second detecting means if the position of said first lens and the position of said second lens detected by said first detecting means deviate from the positional relation stored in said storage circuit, when an in-focus state of said second lens is detected by said focus detecting means.

29. An apparatus according to claim 28, wherein detection of the position of at least either one of said first lens and said second lens is performed on the basis of an amount of movement of said at least either one from a reset position, said first detecting means including a reset position detecting mechanism.

30. An apparatus according to claim 28, wherein said storage circuit has at least stored information which stores a position to be occupied by said second lens when at least said first lens is positioned at or near a wide-angle end, the position detection by said first detecting means being corrected by use of the stored information and information indicative of an actual deviation of the position of said second lens.

31. An apparatus according to claim 28, wherein said optical system is capable of being switched between a normal photography range and a macrophotography range, correction of the position detection by said first detecting means being disabled when said optical system is set to the macrophotography range.

32. An apparatus according to claim 28, further comprising:

operating switch means which can be externally operated,

wherein only when said operating switch means performs a particular operation, correction of the position detection by said first detecting means is executed.

33. An apparatus according to claim 28, wherein correction of the position detection by said first detecting means is cancelled when a power source is turned off.

34. An apparatus according to claim 28, wherein said optical system uses a plastic lens.

35. An apparatus according to claim 30, wherein said optical system uses a plastic lens.

36. An apparatus according to claim 28, wherein the position detection by said first detecting means is corrected with a particular correction value selected from a plurality of correction values.