Auto focus camera with electronic lens disc pawl release arrangement

• US 4,307,952 A
• Filed: 06/03/1980
• Issued: 12/29/1981
• Est. Priority Date: 06/03/1980
• Status: Expired due to Term

• Current Assignee: Polaroid Corporation (PLR IP Holdings LLC)
• Original Assignee: Polaroid Corporation (PLR IP Holdings LLC)
• Inventors: Johnson, Bruce K., Whiteside, George D., Launie, Kenneth J., Bagdis, Judy
• Primary Examiner(s): Hix, L. T.
• Assistant Examiner(s): Perkey, William B.
• Application Number:
  US06/156,044
• Time in Patent Office: 574 Days
• Field of Search: 354/25, 354/195, 354/197, 352/140, 352/142
• US Class Current: 396/105
• CPC Class Codes: G02B 7/40 using time delay of the reflected waves, e.g. of ultrasonic waves
• CPC Class Codes: G03B 19/07 having more than one objective

Abstract

An automatic focusing control apparatus focuses subjects in any one of a plurality of different camera-to-subject distance ranges by transmitting a sonar ranging signal and at the same time displacing an objective lens to move through a plurality of different focal positions corresponding respectively to the different camera-to-subject distance ranges, and thereafter detecting an echo signal from a subject and utilizing the detected echo signal to provide a specially timed control signal to ultimately stop the displacement of the objective lens at the appropriate focal position corresponding to the distance range in which the subject is located.

Claims

1. An automatic lens focusing apparatus for automatically focusing image forming rays at a camera focal plane, said apparatus comprising:

means for generating and transmitting a sonar ranging signal and for providing an indication upon detection of an echo signal reflected from a photographic subject at an elapsed time subsequent to the transmission of the sonar ranging signal;

an objective lens arrangement;

means for mounting said objective lens arrangement for displacement between a plurality of focal positions, said objective lens arrangement being adapted to focus an image of a subject located at a different distance from said objective lens arrangement within a given range of distance at the focal plane of a camera at each of its said focal positions;

means for effecting the displacement of said objective lens arrangement so that said objective lens arrangement reaches each one of its said plurality of focal positions respectively at an elapsed time from its initial displacement greater than the elapsed time from transmission to receipt of an echo signal by said sonar ranging means in an event that a photographic subject is located from said objective lens arrangement by a distance within the given range of distances corresponding to that one focal position in which said objective lens arrangement would focus an image of the subject at the focal plane of the camera; and

means responsive to receipt of an echo signal from a subject by said sonar ranging means for stopping the displacement of said objective lens arrangement at the one focal position in which the objective lens arrangement would focus an image of the subject at the focal plane of the camera, said stopping means operating to stop said objective lens arrangement at an elapsed time subsequent to receipt of the echo signal corresponding to the difference in the elapsed time for said objective lens arrangement to reach its said one focal position from its initial displacement and the elapsed time from transmission to receipt of the echo signal.

2. The automatic lens focusing apparatus of claim 1 wherein said mounting means comprises a plurality of spaced apart catches corresponding respectively to said plurality of focal positions and said stopping means includes means for engaging a respective one of said catches to stop the displacement of said objective lens arrangement and timing means for releasing said catch engaging means to first engage said objective lens arrangement in the space between a pair of adjacent catches such that the continued displacement of the objective lens arrangement operates to thereafter move a respective one of said catches into engagement with said catch engaging means to stop the displacement of said objective lens arrangement at the appropriate focal position corresponding to the distance range in which the subject is located.

3. The automatic focusing apparatus of claim 2 wherein said stopping means also comprises a counter connected to count in correspondence with said sonar ranging signal and a plurality of logic circuits operatively connected with respect to said counter and said sonar ranging means to provide a catch engaging means release signal at an elapsed time subsequent to receipt of the echo signal sufficient to enable said catch engaging means to first engage said objective lens arrangement in the space between the pair of adjacent catches corresponding respectively to the focal positions for the distance range in which the subject is located and the immediately preceeding distance range.

4. The automatic lens focusing apparatus of claim 2 or 3 wherein said lens mounting means comprises a lens holding member disposed for rotation about a center axis and said objective lens arrangement comprises a plurality of lens elements on said lens holding member in circumferentially spaced apart relation with respect to each other about said center axis with each of said lens elements corresponding to a different one of said plurality of focal positions such that rotational displacement of said lens holding member about said center axis by said displacement means operates to sequentially move each of said lens elements into its said one focal position.

5. The lens focusing apparatus of claim 4 wherein said sonar ranging signal is transmitted simultaneously with the initiation of rotational displacement of said lens holding member by said displacement means.

6. The lens focusing apparatus of claim 5 wherein said plurality of spaced apart catches comprise a plurality of notches disposed in circumferentially spaced-apart relation about the outer periphery of said lens holding member and said catch engaging means comprises a lens pawl releasable for engagement against the outer periphery of said lens holding member in the space between a pair of adjacent notches such that the continued rotation of the lens holding member operates to thereafter move a respective one of said notches into position to receive said lens pawl and thereby stop the displacement of said lens holding member.

7. A camera having means for defining a focal plane, said apparatus comprising:

means for generating and transmitting a sonar ranging signal and for providing an indication upon detection of an echo signal reflected from a photographic subject at an elapsed time subsequent to the transmission of the sonar ranging signal;

an objective lens arrangement;

means for mounting said objective lens arrangement for displacement between a plurality of focal positions, said objective lens arrangement being adapted to focus an image of a subject located at a different distance from said camera within a given range of distances at the focal plane of the camera at each of its said focal positions;

means for effecting a displacement of said objective lens arrangement so that said objective lens arrangement reaches each one of its said plurality of focal positions respectively at an elapsed time from its initial displacement greater than the elapsed time from transmission to receipt of an echo signal by said sonar ranging means in an event that a photographic subject is located from said camera by a distance within the given range of distances corresponding to that one focal position in which said objective lens arrangement would focus an image of the subject at the focal plane of said camera; and

means responsive to receipt of an echo signal from a subject by said sonar ranging means for stopping the displacement of said objective lens arrangement at the one focal position in which the objective lens arrangement would focus an image of the subject at the focal plane of said camera, said stopping means operating to stop said objective lens arrangement at an elapsed time subsequent to receipt of an echo signal corresponding to the difference in the elapsed time for said objective lens arrangement to reach its said one focal position from its initial displacement and the elapsed time from transmission to receipt of the echo signal.

8. The camera of claim 7 wherein said mounting means comprises a plurality of spaced apart catches corresponding respectively to said plurality of focal positions and said stopping means includes means for engaging a respective one of said catches to stop the displacement of said objective lens arrangement and timing means for releasing said catch engaging means to first engage said objective lens arrangement in the space between a pair of adjacent catches such that the continued displacement of the objective lens arrangement operates to thereafter move a respective one of said catches into engagement with said catch engaging means to stop the displacement of said objective lens arrangement at the appropriate focal position corresponding to the distance range in which the subject is located.

9. The camera of claim 8 in which said stopping means also comprises a counter connected to count in correspondence with said sonar ranging signal and a plurality of logic circuits operatively connected with respect to said counter and said sonar ranging means to provide a catch engaging means release signal at an elapsed time subsequent to receipt of the echo sufficient to enable said catch engaging means to first engage said objective lens arrangement in the space between the pair of adjacent catches corresponding respectively to the focal positions for the distance range in which the subject is located and the immediately preceeding distance range.

10. The camera of claim 8 or 9 wherein said lens mounting means comprises a lens holding member disposed for rotation about a center axis and said objective lens arrangement comprises a plurality of lens elements on said lens holding member in circumferentially spaced apart relation with respect to each other about said center axis with each of said lens elements corresponding to a different one of said plurality of focal positions such that rotational displacement of said lens holding member about said center axis by said displacement means operates to sequentially move each of said lens elements into its said one focal position.

11. The camera of claim 10 wherein said sonar ranging signal is transmitted simultaneously with the initiation of rotational displacement of said lens holding member by said displacing means.

12. The camera of claim 11 wherein said plurality of spaced apart catches comprise a plurality of notches disposed in circumferentially spaced-apart relation about the outer periphery of said lens holding member and said catch engaging means comprises a lens pawl releasable for engagement against the outer periphery of said lens holding member in the space between a pair of adjacent notches such that the continued rotation of the lens holding member operates to thereafter move a respective one of said notches into position to receive said lens pawl and thereby stop the displacement of said lens holding member.

13. An automatic lens focusing apparatus for automatically focusing image forming rays at a camera focal plane, said apparatus comprising:

means for generating and transmitting a sonar ranging signal and for providing an indication upon detection of an echo signal reflected from a photographic subject at an elapsed time subsequent to the transmission of the sonar ranging signal;

an object lens arrangement;

means for mounting said objective lens arrangement for displacement between a plurality of focal positions, said mounting means comprising a plurality of spaced apart catches corresponding respectively to said plurality of focal positions, said objective lens arrangement being adapted to focus an image of a subject located at a different distance from said objective lens arrangement within a given range of distances at the focal plane of a camera at each of its said focal positions;

means for effecting a displacement of said objective lens so that said objective lens arrangement reaches each one of its said plurality of focal positions at a time correlated to an indication of an echo signal being provided from said sonic ranging means in an event that a subject is located from said objective lens arrangement at a distance at which said objective lens arrangement would focus an image thereof at the camera'"'"'s focal plane; and

means responsive to receipt of an echo signal from a subject by said sonar ranging means for stopping the displacement of said objective lens arrangement at the one focal position in which the objective lens arrangement would focus an image of the subject at the focal plane of the camera, said stopping means comprising means for engaging a respective one of said catches to stop the displacement of said objective lens arrangement and timing means for releasing said catch engaging means at an elapsed time subsequent to receipt of the echo sufficient to enable said catch engaging means to always first engage said objective lens arrangement in the space between a pair of adjacent catches such that the continued displacement of said objective lens arrangement operates to thereafter move a respective one of said catches into engagement with said catch engaging means to stop the displacement of said objective lens arrangement at the appropriate focal position corresponding to the distance range in which the subject is located.

14. The automatic focusing apparatus of claim 13 wherein said stopping means also comprises a counter connected to count in correspondence with said sonar ranging signal and a plurality of logic circuits operatively connected with respect to said counter and said sonar ranging means to provide a catch engaging means release signal at an elapsed time subsequent to receipt of the echo signal sufficient to enable said catch engaging means to first engage said objective lens arrangement in the space between the pair of adjacent catches corresponding respectively to the focal positions for the distance range in which the subject is located and the immediately preceeding distance range.

15. The lens focusing apparatus of claim 13 or 14 wherein said lens mounting means comprises a lens holding member disposed for rotation about a center axis and said objective lens arrangement comprises a plurality of lens elements on said lens holding member in circumferentially spaced apart relation with respect to each other about said center axis with each of said lens elements corresponding to a different one of said plurality of focal positions such that rotational displacement of said lens holding member about said center axis by said displacement means operates to sequentially move each of said lens elements into its said one focal position.

16. The lens focusing apparatus of claim 15 wherein said sonar ranging signal is transmitted simultaneously with an initiation of rotational displacement of said lens holding member by said displacing means.

17. The lens focusing apparatus of claim 16 wherein said plurality of spaced apart catches comprise a plurality of notches disposed in circumferentially spaced-apart relation about the outer periphery of said lens holding member and said catch engaging means comprises a lens pawl releasable for engagement against the outer periphery of said lens holding member in the space between a pair of adjacent notches such that a continued rotation of the lens holding member operates to thereafter move a respective one of said notches into position to receive said lens pawl and thereby stop the displacement of said lens holding member.

18. A camera having means for defining a focal plane, said camera comprising:

means for generating and transmitting a sonar ranging signal and for providing an indication upon detection of an echo signal reflected from a photographic subject at an elapsed time subsequent to the transmission of the sonar ranging signal;

an object lens arrangement;

means for mounting said objective lens arrangement for displacement between a plurality of focal positions, said mounting means comprising a plurality of spaced apart catches corresponding respectively to said plurality of focal positions, said objective lens arrangement being adapted to focus an image of a subject located at a different distance from said camera within a given range of distances at the focal plane of said camera at each of its said focal positions;

means for effecting a displacement of said objective lens so that said objective lens arrangement reaches each one of its said plurality of focal positions at a time correlated to an indication of an echo signal being provided from said sonic ranging means in an event that a subject is located from said camera at a distance at which said objective lens arrangement would focus an image thereof at the camera'"'"'s focal plane; and

means responsive to receipt of an echo signal from a subject by said sonar ranging means for stopping the displacement of said objective lens arrangement at the one focal position in which the objective lens arrangement would focus an image of the subject at the focal plane of the camera, said stopping means comprising means for engaging a respective one of said catches to stop the displacement of said objective lens arrangement and timing means for releasing said catch engaging means at an elapsed time subsequent to receipt of the echo sufficient to enable said catch engaging means to first engage said objective lens arrangement in the space between a pair of adjacent catches such that the continued displacement of said objective lens arrangement operates to thereafter move a respective one of said catches into engagement with said catch engaging means to stop the displacement of said objective lens arrangement at the appropriate focal position corresponding to the distance range in which the subject is located.

19. The automatic focusing apparatus of claim 18 wherein said stopping means also comprises a counter connected to count in correspondence with said sonar ranging signal and a plurality of logic circuits operatively connected with respect to said counter and said sonar ranging means to provide a catch engaging means release signal at an elapsed time subsequent to receipt of the echo signal sufficient to enable said catch engaging means to first engage said objective lens arrangement in the space between the pair of adjacent catches corresponding respectively to the focal positions for the distance range in which the subject is located and the immediately preceeding distance range.

20. The camera of claim 18 or 19 wherein said lens mounting means comprises a lens holding member disposed for rotation about a center axis and said objective lens arrangement comprises a plurality of lens elements on said lens holding member in circumferentially spaced apart relation with respect to each other about said center axis with each of said lens elements corresponding to a different one of said plurality of focal positions such that rotational displacement of said lens holding member about said center axis by said displacement means operates to sequentially move each of said lens elements into its said one focal position.

21. The camera of claim 20 wherein said sonar ranging signal is transmitted simultaneously with an initiation of rotational displacement of said lens holding member by said displacing means.

22. The camera of claim 21 wherein said plurality of spaced apart catches comprise a plurality of notches disposed in circumferentially spaced-apart relation about the outer periphery of said lens holding member and said catch engaging means comprises a lens pawl releasable for engagement against the outer periphery of said lens holding member in the space between a pair of adjacent notches such that the continued rotation of the lens holding member operates to thereafter move a respective one of said notches into position to receive said lens pawl and thereby stop the displacement of said lens holding member.