Slight motion detecting device

• US 5,717,611 A
• Filed: 10/07/1994
• Issued: 02/10/1998
• Est. Priority Date: 10/08/1993
• Status: Expired due to Term

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Ohishi, Sueyuki, Kai, Tadao, Terui, Nobuhiko
• Primary Examiner(s): Trammell, James P.
• Application Number:
  US08/319,642
• Time in Patent Office: 1,222 Days
• Field of Search: 364/566, 364/508, 364/571.01, 364/571.02, 364/571.04, 364/571.05, 364/571.06, 364/571.07, 364/575, 348/500, 348/208, 348/356
• US Class Current: 702/150
• CPC Class Codes: G01H 1/003 of rotating machines G01H1/10 takes precedence
• CPC Class Codes: G03B 2205/0007 Movement of one or more optical elements for control of motion blur
• CPC Class Codes: G03B 2217/005 Blur detection
• CPC Class Codes: G03B 5/00 Adjustment of optical system relative to image or object surface other than for focusing

Abstract

A slight motion detecting device includes a angular velocity sensor, a low pass filter, a high pass filter, an amplifier, and a CPU. The CPU differentiates an output from the angular velocity sensor so as to obtain an angular acceleration, and determines that a peak of the acceleration is obtained at the time at which the sign of the acceleration is changed, and further, calculates a zero level detection value of the angular velocity, from the peak, thereby the output of the angular velocity sensor is corrected in accordance with the zero level detection value.

Claims

1. A slight motion detecting device comprising:

a slight motion detecting unit to detect a slight motion;

an extreme value detecting unit to detect extreme values of outputs from said slight motion detecting unit;

a prezero level detecting unit to detect a prezero level corresponding to an output from said slight motion detecting unit in the case of no slight motion, in accordance with an output from said extreme value detecting unit; and

a slight motion output correcting unit to correct an output from said slight motion detecting unit in accordance with a signal from said prezero level detecting unit.

2. A slight motion detecting device comprising:

a slight motion detecting unit to detect a slight motion;

an amplifying unit to amplify a signal from said slight motion detecting unit;

an extreme value detecting unit to detect extreme values of outputs from said amplifying unit;

a prezero level detecting unit to detect a prezero level corresponding to an output from said amplifying unit in the case of no slight motion, in accordance with an output from said extreme value detecting unit; and

a slight motion output correcting unit to correct an output from said amplifying unit in accordance with a signal from said prezero level detecting unit.

3. A slight motion detecting device comprising:

a slight motion detecting unit to detect a slight motion;

an extreme value detecting unit to detect extreme values of outputs from said slight motion detecting unit;

a prezero level detecting unit to detect a prezero level corresponding to an output from said slight motion detecting unit in the case of no slight motion, in accordance with an output from said extreme value detecting unit;

a moving average calculating unit to move an average of outputs from said prezero level detecting means; and

a slight motion output correcting unit to correct an output from said slight motion detecting unit in accordance with a signals from said moving average calculating unit.

4. A slight motion detecting device comprising:

a slight motion output unit to output a detection signals corresponding to slight motion;

a differentiating unit to differentiate said detection signal and to output a differentiated signal;

a sign change detecting unit to detect a change of the sign of said differentiated signal;

a reference level calculating unit to calculate a reference level for said detection signal in accordance with said detection signal until the sign of said differentiated signal is changed from one to the other with the change of said sign being detected by said sign change detecting unit; and

a slight motion amount correcting unit to correct said slight motion in accordance with said reference level.

5. A device as set forth in claim 4, wherein said sign change detecting unit includes a stopping unit to stop detection of said sign change for a predetermined time from the time when said sign change is detected.

6. A device as set forth in claim 4, further comprising:

a display unit to change a display configuration in accordance with a slight motion detected by said slight motion amount correcting unit; and

a reference level number measuring unit to measure a number of said reference levels repeatedly calculated by said reference level calculating unit, wherein said display unit stops its display operation when a number calculated by said reference level number measuring unit is less than a predetermined number.

7. A device as set forth in claim 4, further comprising:

a display unit to change the display configuration in accordance with a slight motion detected by said slight motion amount correcting unit; and

a reference level number measuring unit to measure a number of said reference levels repeatedly calculated by said reference level calculating unit, wherein said display unit displays a configuration different from a display configuration in accordance with the degree of slight motion is a number calculated by said reference level number measuring unit is less than a predetermined number.

8. A device as set forth in claim 4, wherein said slight motion output unit outputs an angular velocity signal in accordance witch said slight motion.

9. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal corresponding to slight motion;

a differentiating unit to differentiate said detection signal and to output a differentiated signal;

an averaging unit to average said differentiated signal and to output an averaged signal;

a sign change detecting unit to detect a change of the sign of said averaged signal;

a reference level calculating unit to correct a reference level for said detection signal in accordance with said detection signal until the sign of said averaged signal is changed from one to the other with the change of said sign being detected by said sign change detecting unit; and

a slight motion correcting unit to correct said slight motion in accordance with said reference level.

10. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal corresponding to slight motion;

an averaging unit to average said detection signal and to output an averaged signal;

a differentiating unit to differentiate said averaged signal and to output a differentiated signal;

a sign change detecting unit to detect a change of the sign of said differentiated signal;

a reference level calculating unit to calculate a reference level for said detection signal in accordance with said detection signal until the sign of said differentiated signal is changed from one to the other with the change of said sign being detected by said sign change detecting unit; and

a slight motion correcting unit to correct said slight motion in accordance with said reference level.

11. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal corresponding to slight motion;

a differentiating to differentiate said detection signal and to output a differentiated signal;

a sign change detecting unit to detect a change of the sign of said differentiated signal;

a reference level calculating unit to calculate a reference level for said detection signal in accordance with said detection signal until the sign of said differentiated signal is changed from one to the other with the change of said sign being detected by said sign change detecting unit; and

a reference level detecting precision improving unit to average the repeatedly calculated reference levels which are calculated by said reference level calculating unit; and

a slight motion correcting unit to correct said slight motion in accordance with an output from said reference level detecting precision improving unit.

12. A device as set forth in claim 11, wherein said reference level detecting precision improving unit averages a predetermined number of those of the repeatedly calculated reference levels, which have been lastly calculated, or all of the repeatedly calculated reference levels if all said repeatedly calculated reference levels have a number less than said predetermined number.

13. A device as set forth in claim 11, further comprising a reference level extracting unit to extract those of said repeatedly calculated reference levels which fall in a first reference range, wherein said reference level detecting precision improving unit averages said reference levels extracted by said reference level extracting unit.

14. A device as set forth in claim 13, further comprising a measuring unit to measure a number of reference levels extracted by said reference level extracting unit, wherein said reference level extracting unit extracts the reference levels which fall in a second reference range which is broader than the first reference range if said measured number is less than a predetermined number.

15. A device as set forth in claim 13, further comprising a measuring means for measuring a number of the reference levels extracted by said reference level extracting unit, wherein said reference levels extracting unit extracts the reference level which falls in a second reference range narrower than the first reference range if said measured number is greater than a predetermined number.

16. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal corresponding to slight motion;

an amplifying unit to amplify said detection signal;

a differentiating unit to differentiate an output from said amplifying unit and to output a differentiated signal;

a sign change detecting unit to detect a change of the sign of said differentiated signal;

a reference level calculating unit to calculate a reference level for said amplified detection signal in accordance with said amplified detection signal until the sign of said differentiated signal is changed from one to the other with the change of said sign being detected by said sign change detecting unit; and

a slight motion correcting unit to correct said amplified detection signal in accordance with said reference level.

17. A device as set forth in claim 16, wherein said amplifying unit further comprises a change-over unit to change whether a detection signal delivered from said slight motion output unit is inputted or a predetermined level signal is inputted;

and

an offset control unit to carry out such a control that said change-over unit is changed over so as to input said predetermined level signal to said amplifying unit for a predetermined time when the signal level of said detection signal amplified by said amplifying unit, becomes substantially equal to said reference level calculated by said reference level calculated unit.

18. A device as set forth in claim 17, further comprising a time measuring unit to measure a time by which the signal level of said detection signal amplified by said amplifying unit becomes substantially equal to said reference level, wherein when the time measured by said time measuring unit exceeds a predetermined time, the control by said offset control means is stopped.

19. A device as set forth in claim 18, further comprising a forced offset control unit to change over said change-over unit so as to input a predetermined level signal to said amplifying unit by a predetermined time when the control by said offset control unit is stopped.

20. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal in accordance with a slight motion;

an averaging unit to average said detection signal for every predetermined time;

a reference level calculating unit to repeatedly calculate reference levels of said detection signal corresponding to the case of no slight motion in accordance with said averaged detection signal;

a reference level detecting precision improving unit to average said repeatedly calculated reference levels which are calculated by said reference level calculating unit; and

a slight motion correcting unit to correct said slight motion in accordance with an output from said reference level detecting precision improving unit.

21. A device as set forth in claim 20, wherein said reference level detecting precision improving unit averages a predetermined number of those of said repeatedly calculated reference levels, which are lastly calculated, or averages all said repeatedly calculated reference levels if a number of already calculated reference levels is less than said predetermined number.

22. A device as set forth in claim 20, further comprising a reference level extracting unit to extract those of said repeatedly calculated reference levels which fall in the first reference range, wherein said reference level detecting unit averages the reference levels extracted by said reference level extracting unit.

23. A device as set forth in claim 22, further comprising a measuring unit to measure a number of the reference levels extracted by said reference level extracting unit, wherein said reference level extracting unit extracts the reference levels in a second reference range which is broader than said first reference range if said measured number is less than a predetermined number.

24. A device as set forth in claim 22, further comprising a measuring unit to measure a number of the reference levels extracted by said reference level extracted by said reference level extracting unit, wherein said reference level extracting unit extracts the reference levels which fall in a second reference range narrower than said first reference range if said measured number is greater than a predetermined number.

25. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal in accordance with a slight motion;

an amplifying unit to amplify said detection signal;

an averaging unit to average an output from said amplifying unit for every predetermined time;

a reference level calculating unit to repeatedly calculate reference levels of said amplified detection signal corresponding to the case of no slight motion in accordance with an output from said averaging unit;

a reference level detecting precision improving unit to average said repeatedly calculated reference levels which are calculated by said reference level calculating unit; and

a slight motion correcting unit to correct said amplified detection signal in accordance with an output from said reference level detecting precision improving unit.

26. A device as set forth in claim 25, further comprising:

a change-over unit to change over whether said detection signal delivered from said slight motion output unit is inputted to said amplifying unit or a predetermined level signal is inputted thereto; and

an offset control unit to control change-over of said change-over unit so as to input said predetermined level signal to said amplifying unit for a predetermined time when the signal level of said detection signal amplified by said amplifying unit becomes substantially equal to said reference level calculated by said reference level calculating unit.

27. A device as set forth in claim 26, further comprising a time measuring unit to measure a time by which the signal level of said detection signal amplified by said amplifying unit becomes substantially equal to said reference level, wherein when the time measured by said time measuring unit exceeds a predetermined time, the control by said offset control unit is stopped.

28. A device as set forth in claim 27, further comprising a forced offset control unit to change over said change-over unit so as to input said predetermined level signal to said amplifying unit by a predetermined time when the control by said offset control unit is stopped.

29. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal in accordance with a slight motion;

an averaging unit to average said detection signal for every predetermined time;

a reference level calculating unit to calculate a reference level of said detection signal corresponding to the case of no slight motion in accordance with said averaged detection signal;

a slight motion correcting unit to correct said slight motion in accordance with said reference level;

a display unit to change a display configuration in accordance with a slight motion detected by said slight motion correcting unit; and

a reference level number measuring unit to measure a number of said reference levels repeatedly calculated by said reference level calculating unit, wherein said display unit stops its display operation when a number calculated by said reference level number measuring means is less than a predetermined number.

30. A device as set forth in claim 29, wherein said slight motion output unit outputs an angular velocity signal in accordance with said slight motion.

31. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal in accordance with a slight motion;

an averaging unit to average said detection signal for every predetermined time;

a reference level calculating unit to calculate a reference level of said detection signal corresponding to the case of no slight motion in accordance with said averaged detection signal;

a slight motion correcting unit to correct said slight motion in accordance with said reference level;

a display unit to change the display configuration in accordance with a slight motion detected by said slight motion correcting unit; and

a reference level number measuring unit to measure a number of said reference levels repeatedly calculated by said reference level calculating unit, wherein said display unit displays a configuration different from a display configuration in accordance with said slight motion if a number calculated by said reference level number measuring unit is less than a predetermined number.

32. A slight motion detecting device comprising:

a slight motion output unit to deliver a detection signal in accordance with a slight motion;

an amplifying unit to amplify said detection signal;

a change-over unit to change over whether said detection signal is inputted to said amplifying unit or a zero level signal is inputted thereto;

an offset control unit to control change-over of said change-over unit so that an output from said amplifying unit when a reference level signal from said slight motion output unit, corresponding to the case of no slight motion, is inputted to said amplifying unit, becomes substantially equal to an output which is obtained from said amplifying unit when a zero level signal is inputted to said amplifying unit.

33. A device as set forth in claim 32, wherein said slight motion output unit outputs an angular velocity signal in accordance with said slight motion.

34. A slight motion detecting device comprising:

a slight motion output unit to output a detection signal in accordance with a slight motion;

a display unit to change a display configuration in accordance with a signal level of said detection signal; and

a maximum or minimum level detecting unit to detect a maximum or minimum value of signal levels of said detection signal for every predetermined time,

wherein said display unit changes the display configuration in accordance with said detected maximum or minimum value of said signal levels for every predetermined time.

35. A device as set forth in claim 34, wherein said slight motion output unit outputs an angular velocity signals in accordance with said slight motion.