Camera having superimposed information display device

• US 5,525,792 A
• Filed: 09/26/1994
• Issued: 06/11/1996
• Est. Priority Date: 01/18/1990
• Status: Expired due to Term

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Kusaka, Yosuke
• Primary Examiner(s): ALLEN, STEPHONE B
• Application Number:
  US08/311,896
• Time in Patent Office: 624 Days
• Field of Search: 250/201.8, 250/204, 354/402, 354/404-408, 354/430, 354/173.11
• US Class Current: 250/201.8
• CPC Class Codes: G02B 7/346 using horizontal and vertical areas in the pupil plane, i.e. wide area autofocusing

Abstract

Disclosed is a focus detecting device for use in a camera comprising a phototaking optical system for forming an image of the object on a reference plane. A focus detecting optical system separates light passing through the phototaking system from at least a pair of light beams passing through spatially different areas on a first predetermined plane axially spaced by a first distance from the reference plane, and thereby forming images of the object. A photoelectric converting device generates object image signals corresponding to the intensity distribution of the object images formed by the focus detecting optical system. A phototaking optical information device generates information on the shape of exit pupil at fully-open diaphragm of the phototaking system and on a second distance from the reference plane to the exit pupil. A focus detecting optical information device generates information on the areas on the first predetermined plane and on the first distance. A light amount distribution detecting device determines the decrease in light amount on the plane of photosensor elements of the photoelectric converting device as light amount information relating to the position on the plane of photosensor elements, encountered when the phototaking system and the focus detecting system are combined, based on the information from the phototaking optical information device and from the focus detecting optical information device. A focus detection calculation device determines the defocus amount of the current object image plane relative to the reference plane based on the light amount distribution information.

Claims

1. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

a focus detecting circuit which detects a focus condition of an image plane formed by said phototaking optical system relative to the prearranged focal plane in a focus detecting position provided in the image field;

a finder having a finder image field for observing an image of an object formed by said phototaking optical system;

a displaying device which displays a focus condition detected by said focus detecting circuit superimposed on an image of an object in a position corresponding to the focus detecting position on the said finder image field;

a driving device which drives said phototaking optical system;

a drive controller which controls driving of said phototaking optical system, said drive controller having the following two focus modes,

(1) manual focus mode for manually focusing said phototaking optical system regardless of a focus condition,

(2) auto focus mode for driving said phototaking optical system to a focus point with said driving device in accordance with a focus condition;

a focus mode designating member which designates one of said focus modes to allow said drive controller to drive-control in the designated mode; and

a display controller which allows said displaying device to operate in case the auto focus mode is designated by said focus mode designating member while inhibiting said displaying device from operating in case the manual focus mode is designated by said focus mode designating member.

2. A camera according to claim 1, which further comprises a housing which houses said finder and said displaying device.

3. A camera according to claim 1, wherein said displaying device has an electrooptical device and a transparent electrode.

4. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

a focus detecting circuit which detects a focus condition of an image plane formed by said phototaking optical system relative to the prearranged focal plane in a focus detecting position provided in the image field;

an adjusting device having a plurality of modes for adjusting said phototaking optical system based on the detected focus condition;

a finder having a finder image field for observing an image of an object formed by said phototaking optical system;

a displaying device which displays a focus condition detected by said focus detecting circuit superimposed on an image of an object in a position corresponding to the focus detecting position on said finder image field;

a selecting member which selects one of said plurality of modes; and

a display controller which controls an operation of said displaying device in accordance with the selected mode.

5. A camera according to claim 4, wherein said focus detecting circuit has a plurality of focus detecting positions provided in the image field, and which further comprises a focus position selecting circuit which selects one of said plurality of focus detecting positions.

6. A camera according to claim 4, which further comprises a housing which houses said finder and said displaying device.

7. A camera according to claim 4, wherein said displaying device has an electrooptical device and a transparent electrode.

8. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

a focus detecting circuit which detects a focus condition of an image plane formed by said phototaking optical system relative to the prearranged focal plane in a focus detecting position provided in the image field;

a finder having a finder image field for observing an image of an object formed by said phototaking optical system;

a displaying device which displays said focus detecting position superimposed on an image of an object on said finder image field, based on the detected focus condition;

a selecting member which selects one of a plurality of focusing modes; and

a display controller which controls an operation of said displaying device in accordance with the selected mode.

9. A camera according to claim 8, which further comprises a housing which houses said finder and said displaying device.

10. A camera according to claim 8, wherein said displaying device has an electrooptical device and a transparent electrode.

11. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

a focus detecting circuit which detects a focus condition of an image plane formed by said phototaking optical system relative to the prearranged focal plane in a focus detecting position provided in the image field;

a finder having a finder image field for observing an image of an object formed by said phototaking optical system;

a displaying device which displays a photographing information superimposed on an image of an object on said finder image field;

a selecting member which selects one of a plurality of focusing modes; and

a display controller which controls an operation of said displaying device in accordance with the selected mode.

12. A camera according to claim 11, which further comprises a housing which houses said finder and said displaying device.

13. A camera according to claim 11, wherein said displaying device has an electrooptical device and a transparent electrode.

14. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

a focus detecting circuit which detects a focus condition of an image plane formed by said phototaking optical system relative to the prearranged focal plane in a focus detecting position provided in the image field;

a finder having a finder image field for observing an image of an object formed by said phototaking optical system;

a displaying device which displays focus information superimposed on an image of an object on said finder image field;

a selecting member which selects one of a plurality of operation modes; and

a display controller which inhibits said displaying device from operating in accordance with the selected mode.

15. A camera according to claim 14, which further comprises a housing which houses said finder and said displaying device.

16. A camera according to claim 14, wherein said displaying device has an electrooptical device and a transparent electrode.

17. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

a focus detecting position selecting circuit which selects one of a plurality of focus detecting positions provided in the image field;

a focus detecting circuit which detects a focus condition of an image plane formed by said phototaking optical system relative to the prearranged focal plane in a focus detecting position selected by said focus detecting position selecting circuit;

a finder having a finder image field for observing an image of an object formed by said phototaking optical system;

a displaying device which displays a focus frame corresponding to the selected focus detecting position superimposed on an image of an object on said finder image field; and

a display changing circuit which changes said focus frame according to the detected focus condition.

18. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

an area sensor for receiving a pair of object images formed by a pair of light fluxes passing through different portions of an exit pupil of said phototaking optical system;

a focus detecting circuit which detects a focus condition in a plurality of focus detecting positions provided in the image field, based on an output of said area sensor; and

an electrical view finder responsive to the output of said area sensor which displays an image of an object formed by said phototaking optical system.

19. A camera comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

an area sensor for receiving a pair of object images formed by a pair of light fluxes passing through different portions of an exit pupil of said phototaking optical system;

a focus detecting circuit which detects a focus condition in a plurality of focus detecting positions provided in the image field, based on an output of said area sensor; and

an outputting device which transfers the output of said area sensor to the outside of said camera.

20. A camera having a display device comprising:

a phototaking optical system for forming an image of an object in an image field provided in a prearranged focal plane;

a focus detecting circuit which detects a focus condition of an image plane formed by said phototaking optical system relative to the prearranged focal plane in a focus detecting position provided in the image field;

a finder having a finder image field for observing an image of an object formed by said phototaking optical system;

a displaying device which displays a focus condition detected by said focus detecting circuit superimposed on an image of an object in a position corresponding to the focus detecting position on said finder image field;

an operating member which selects whether or not to superimposingly display the focus condition with said displaying device; and

a display controller which controls an operation of said displaying device in accordance with the selection of said operating member.

21. A camera according to claim 20, which further comprises a housing which houses said finder and said displaying device.

22. A camera according to claim 20, wherein said displaying device has an electrooptical device and a transparent electrode.