System for Exposure Measurement and/or Focus Detection by Means of Image Sensor

1. An exposure measurement system comprising; a plurality of photoelectric converting elements each for converting a portion of a light beam into an electrical signal corresponding to a portion of the light beam, scanning means electrically coupled with said elements for sensing the outputs of the elements one after another, digital converting means coupled to said scanning means for converting the sensed outputs of the photoelectric converting elements into digital signals, a processing device coupled to said digital converting means for processing the output of the photoelectric converting elements converted into digital values by means of the digital converting means in accordance with a predetermined estimation function so as to determine an exposure value.[...]. and control means for controlling the processing operation of said processing device, said control means being operable for causing the processing device to select optional elements whose outputs are to be utilized for the determination of the exposure value.

2. An exposure measurement system in accordance with claim 1, further comprising; an indication means electrically coupled to the processing device for indicating the exposure value on the basis of the exposure measurement information produced by the processing device.

3. An exposure measurement system in accordance with claim 1, said processing device comprising; an addition circuit electrically connected with the digital convertng means for summing a plurality of the outputs of the photoelectrical converting elements converted into digital value, a division circuit electrically coupled to the addition circuit for dividing the value obtained from the addition circuit by the number of the elements whose outputs have been summed by the addition circuit, a processing circuit electrically coupled to the division circuit for processing the exposure value in accordance with the output value of the division circuit.

4. An exposure measurement system in accordance with claim 1, said processing device comprising; a first addition circuit for summing all the outputs of the photoelectric converting elements converted into digital values, said circuit being electrically coupled to the digital converting means, a first division circuit for dividing the value obtained from the first addition circuit by the total number of the elements, said circuit being electrically coupled to the first addition circuit, a second addition circuit for summing a predetermined number of the outputs of the photoelectric converting elements converted into digital values less than the total number of the outputs of the photoelectric converting elements converted in digital values, said circuit being electrically coupled to the digital converting means, a second division circuit for dividing the value obtained from the second addition circuit by the number of the elements whose outputs have been summed by the second addition circuit, said circuit being electrically coupled to the second addition circuit, selection means electrically coupled to both of the division circuits for selecting the value from the second division circuit when the difference between the value from the first division circuit and that from the second division circuit is larger than a predetermined value, and for selecting the value from the first division circuit when the difference is smaller than the predetermined value, a processing circuit for processing the exposure value on the basis of the output value selected by the selection means, said circuit being electrically coupled to the selection means.

5. An exposure measurement system in accordance with claim .[.5.]. 4, further comprising: switch means for actuating at least one of said first addition and division circuits and second addition and division circuits, said switch means being electrically coupled to the first addition and division circuits and second addition and division circuits.

6. An exposure control system comprising a plurality of photoelectric converting elements each for converting a portion of a light beam into an electrical signal corresponding to a portion of the light beam. scanning means electrically coupled with said elements for sensing the outputs of the elements one after another, digital converting means coupled to said scanning means for converting the sensed outputs of the photoelectric converting elements into digital signals, control means for controlling the processing operation of said processing device, said control means being operable for causing the processing device to select optional elements whose outputs are to be utilized for the determination of the exposure value, and a processing device coupled to said digital converting means for processing the output of the photoelectric converting elements converted into digital values by means of the digital converting means in accordance with a predetermined estimation function so as to determine an exposure value, and exposure adjusting means electrically coupled to the processing device for adjusting the exposure value on the basis of the exposure measurement information produced by the processing device.

7. An exposure measurement system for a camera comprising; photoelectric converting means for converting light beam into electrical signals, said means being arranged in the path of the light beam coming from a photographic scene to be photographed by the camera and comprising a number of photoelectric converting elements for producing the electrical outputs corresponding to the brightness of the photographic scene, series detecting means for sequentially sensing the outputs of the photoelectric converting elements, said means being electrically coupled to the photoelectric converting means and sensing the outputs of the photoelectric converting elements in sequence and transmitting the outputs of the photoelectric converting elements one by one, digital converting means for successively converting the successive outputs of the detecting means into digital values, said means being electrically coupled to the output terminal of the photoelectric converting means, a processing device for determining the exposure value by processing the outputs converted into digital values by means of the digital converting means in accordance with a predetermined estimation function, so as to determine the exposure value, said device comprising; addition means for summing a plurality of the outputs of the photoelectric converting elements converted into digital values of the photoelectric converting elements, said means being electrically coupled to the digital converting means, division means for dividing the value obtained from the addition means by the number of the elements whose outputs have been summed by the addition means, said means being electrically coupled to the addition means, processing means for processing the exposure value on the basis of the value obtained from the dividing means, said means being electrically coupled to the dividing means.

8. A camera capable of an exposure measurement by converting the light beam coming from the photographic scene through a photo-taking optical system into electrical signals comprising; image sensing means including a number of the photoelectric converting elements, said means being arranged in the path of the light beam coming through the photo-taking optical system and producing outputs corresponding to the brightness of the photographic scene, time series means for producing a time series of the outputs of the photoelectric converting elements, said series means being electrically coupled to the image sensing means and producing a time series of the outputs of the photoelectric converting elements by transmitting the outputs of the photoelectric converting elements one by one, digital converting means for successively converting the time series of the outputs of the photoelectric converting elements produced by means of the time series means into digital values, said means being electrically coupled to the image sensing means, a processing device for determining the exposure value by processing the outputs converted into digital values by means of the digital converting means in accordance with a predetermined estimation function so as to determine the exposure value, said device being electrically coupled to the digital converting means.[...]. , and control means for controlling the processing operation of said processing device, said control means being operable for causing the processing device to select optional elements whose outputs are to be utilized for the determination of the exposure value.

9. A camera in accordance with claim 8 further comprising; indication means for indicating the exposure value determined by the processing device, said means being electrically coupled to the processing device.

10. A camera in accordance with claim 8, further comprising; an exposure adjustment device for adjusting the exposure in accordance with the exposure value determined by means of the processing device, said device being electrically coupled to the processing device.

11. A camera in accordance with claim 8, said processing device comprising; an addition circuit for summing a plurality of the outputs of the photoelectrical converting elements converted into digital value, said circuit being electrically coupled to the digital converting means, a division circuit for dividing the value obtained from the addition circuit by the number of the elements whose outputs have been summed by the addition circuit, said circuit being electrically coupled to the addition circuit, a processing circuit for processing the exposure value in accordance with the value obtained from the division circuit, said circuit being electrically coupled to the division circuit.

12. A camera in accordance with claim 8, said processing device comprising: a first addition circuit for summing all the outputs of the photoelectric converting elements converted into digital values, said circuit being electrically coupled to the digital converting means, a first division circuit for dividing the value produced by the first addition circuit by the total number of the elements, said circuit being electrically coupled to the first addition circuit, a second addition circuit for summing a predetermined number of outputs of the elements converted into digital values less than the total number of the outputs of the photoelectric converting elements converted into digital values, said circuit being electrically coupled to the digital converting means, a second division circuit for dividing the value produced by the second addition circuit by the number of the elements whose outputs have been summed by the second addition circuit, said circuit being electrically coupled to the second addition circuit, selection means for selecting the value produced by the first division circuit or that produced by the second division circuit, said selection means being electrically coupled to both of the division circuits so as to select the value produced by the second division circuit when the difference between the value produced by the first division circuit and that produced by the second division circuit is larger than a predetermined value, and select the value produced by the first division circuit when the difference is smaller than the predetermined value, a processing circuit for processing the exposure value in accordance with the value selected by the selection means, said circuit being electrically coupled to the selection means.

13. A camera in accordance with claim 12, further comprising; switch means for actuating either the first addition and division circuits or the second addition and division circuits, said switch means being electrically connected with the first and the second addition and division circuits.

14. A system comprising; an image forming optical system, at least a part of said optical system being movable along an optical axis so as to form an image of an object at a predetermined position, photoelectric converting means for converting a light beam into electrical signals, said converting means being arranged at the predetermined position and comprising a number of photoelectric converting elements each producing an electrical output corresponding to a portion of the light beam, time series means coupled to the elements for producing a time series of the outputs of the photoelectric converting elements, said series means being electrically connected with the photoelectric converting elements and .[.making.]. forming the time series of the outputs of the photoelectric converting elements by successively transmitting the outputs of the photoelectric converting elements, digital converting means coupled to the photoelectric converting means for successively converting the time series outputs of the photoelectric converting elements into digital values, a processing device for processing the outputs of the photoelectric converting elements converted into digital values by means of the digital converting means in accordance with a predetermined estimation function so as to detect the focusing condition of the image forming optical system, said device being electrically coupled to the digital converting means so as to produce focusing information of the optical system by processing the outputs of the photoelectric converting elements converted into digital values in accordance with the predetermined estimation function.

15. A system in accordance with claim 14, further comprising: indication means for indicating the focusing condition of the image forming optical system on the basis of the focusing information produced by the processing device.

16. A system according to claim 14, further comprising; adjusting means for adjusting the image forming optical system in response to the output of the processing device so that the object image is formable at the predetermined position, said means being functionally engaged with the image forming optical system and electrically coupled to the processing device.

17. A camera comprising: a photo-taking optical system, at least a part of said system being movable along an optical axis so as to form an image of the object to be photographed at a predetermined position, image sensing means including a number of photoelectric converting elements arranged on a same plane, said sensing means being arranged at a position optically equivalent to the predetermined position and each element in said means producing an electrical output corresponding to a portion of a light beam coming through said optical system, time series means for producing a time series of the outputs of the photoelectric converting elements, said time series means being electrically coupled to the image sensing means and producing the time series of the outputs by successively transmitting the outputs of the photoelectric converting means, digital converting means for successively converting the time series outputs of the photoelectric converting elements, into digital values, said converting means being electrically coupled to the image sensing means, a processing device for processing the outputs of the photoelectric converting elements converted into digital values by means of digital converting means in accordance with a predetermined estimation function so as to detect the focusing condition of the optical system, said device being electrically coupled to the digital converting means so as to produce focusing information by processing the outputs of the photoelectric converting elements converted into digital values in accordance with the predetermined estimation function.

18. A camera in accordance with claim 17, further comprising; indication means coupled to the processing device for indicating the focusing condition of the photo-taking optical system in accordance with the focusing information produced by the processing device.

19. A camera in accordance with claim 17, further comprising; adjusting means for adjusting the photo-taking optical system in accordance with the focusing information produced by the processing device so that the image of the object to be photographed may be formed at the predetermined position, said adjusting means being functionally engaged with the movable part of the photo-taking optical system and electrically connected with the processing device.

20. A camera in accordance with claim 17, said processing device comprising; a processing circuit for producing the absolute values of the differences between the outputs of pairs of adjacent photoelectric converting elements converted into digital values, said circuit being electrically coupled to the digital converting means, an integrating circuit for successively integrating the values produced by the processing circuit, said circuit being electrically coupled to the processing circuit, a detecting circuit for detecting the maximum value of the value produced by the integrating circuit during the variation of the same in accordance with the movement of the movable part of the photo-taking optical system, said circuit being electrically coupled to the integrating circuit and producing a focusing signal when the maximum value of the integrated values is detected.

21. A camera in accordance with claim 20, further comprising; driving means capable of responsing to the focussing signal produced by the detecting circuit and of moving the movable part of the photo-taking optical system along the optical axis, said driving means being functionally engaged with the movable part of the photo-taking optical system and electrically coupled to the detecting circuit so as to move the movable part of the photo-taking optical system along the optical axis until the detecting circuit produces the focussing signal.

22. A camera in accordance with claim 20, further comprising; indication means for indicating the focussing condition relative to the object to be photographed, of the photo-taking optical system in accordance with the focussing signal produced by the detecting circuit, said indication means being electrically connected with the detecting circuit.

23. A system capable of both exposure measurement and detection of focusing condition of an image forming optical system settable along an optical axis to form an image of an object at a predetermined position, comprising photoelectric converting means for converting a light beam into electrical signals, said converting means being arranged at the predetermined position, and including a number of photoelectric converting elements producing electric outputs corresponding to the light beam, time series producing means coupled to said converting elements for producing a time series of the outputs of the photoelectric converting elements by successively transmitting the outputs of the photoelectric converting elements, digital converting means for successively converting the time series outputs of the photoelectric converting elements produced by the time series means into digital values, said converting means being electrically connected with the photoelectric converting means, a first processing device for processing the outputs of the photoelectric converting elements converted into digital values in accordance with a first predetermined estimation function so as to detect the focusing condition of the optical system, said device being electrically connected with the digital converting means, a second processing device for processing the outputs of the photoelectric converting elements converted into digital values by means of the digital converting means on the basis of a second predetermined estimation function, so as to determine an exposure value, said second processing device being electrically connected with the digital converting means.

24. A system in accordance with claim 23, further comprising; indication means coupled to the first processing device for indicating the focusing condition of the image forming optical system in acordance with the focus point detection information produced by the first processing device.

25. A system in accordance with claim 23, further comprising; indication means for indicating the exposure value determined by the exposure measurement information produced by the second processing device, said means being electrically connected with the second processing device.

26. A system for exposure measurement and focus adjustment of an image forming optical system settable along an optical axis to form an image of an object at a predetermined position, comprising photoelectric converting means for converting a light beam into electrical signals, said converting means being arranged at the predetermined position, and including a number of photoelectric converting elements producing electric outputs corresponding to the light beam, time series producing means coupled to said converting elements for producing a time series of the outputs of the photoelectric converting elements by successively transmitting the outputs of the photoelectric converting elements, digital converting means for successively converting the time series output of the photoelectric converting elements produced by the time series means into digital values, said converting means being electrically connected with the photoelectric converting means, a first processing device for processing the outputs of the photographic converting elements converted into digital values in accordance with a first predetermined estimation function so as to detect the focusing condition of the optical system, said device being electrically connected with the digital converting means, a second processing device for processing the outputs of the photoelectric converting elements converted into digital values by means of the digital converting means on the basis of a second predetermined estimation function, so as to determine an exposure value, said second processing device being electrically connected with the digital converting means, and adjusting means for adjusting the image forming optical system in accordance with the output of the first processing device, so that the image of the object may be formed at the predetermined position, said means being functionally engaged with the image forming optical system and electrically connected with the first processing device.

27. A system for exposure control and detection of focusing condition of an image forming optical system setting along an optical axis to form an image of an object at a predetermined position, comprising photoelectric converting means for converting a light beam into electrical signals, said converting means being arranged at the predetermined position, and including a number of photoelectric converting elements producing electric outputs corresponding to the light beam, time series producing means coupled to said converting elements for producing a time series of the outputs of the photoelectric converting elements by successively transmitting the outputs of the photoelectric converting elements, digital converting means for successively converting the time series outputs of the photoelectric converting elements produced by the time series means into digital values, said converting means being electrically connected with the photoelectric converting means, a first processing device for processing the outputs of the photoelectric converting elements converted into digital values in accordance with a first predetermined estimation function so as to detect the focusing condition of the optical system, said device being electrically connected with the digital converting means, a second processing device for processing the outputs of the photoelectric converting elements converted into digital values by means of the digital converting means on the basis of a second predetermined estimation function, so as to determine an exposure value, said second processing device being electrically connected with the digital converting means, and exposure adjusting means for adjusting the exposure value on the basis of the exposure measurement information produced by the second processing device, said means being electrically connected with the second processing devices.

28. A camera capable of both exposure measurement and focus point detection of a photo-taking optical system settable along an optical axis so as to form an image of an object at a predetermined position comprising; image sensing means having a number of photoelectric converting elements arranged a same plane, said sensing means being arranged at a position optically equivalent to the predetermined position and each element in said means producing an electrical output corresponding to a portion of a light beam coming through the optical system from the object, time series means for producing a time series of the outputs of the photoelectric converting elements said means being electrically connected with the image sensing means and producing the time series of the photoelectric converting elements by successively delivering the outputs of the photoelectric converting elements, digital converting means for successively converting the time series outputs of the photoelectric converting elements produced by the time series means into digital values, said means being electrically connected with the image sensing means, a first processing device for processing the outputs of the photoelectric converting elements converted into digital values by means of the digital converting means, in accordance with a first predetermined estimation function, so as to detect the focusing condition of the optical system, said device being electrically connected with the digital converting means and producing focusing detection information of the optical system by processing the outputs of the elements converted into digital values in accordance with the first estimation function, a second processing device for processing the outputs of the photoelectric converting elements converted into digital values by means of the digital converting means in accordance with a second predetermined estimation function, so as to determine the exposure value, said device being electrically connected with the digital converting means and producing the exposure measurement information by processing the outputs of the elements converted into digital values in accordance with the second estimation function.

29. A camera in accordance with claim 28, said first processing device comprising; a processing circuit for producing the absolute values of the differences between the outputs of pairs of adjacent photoelectric converting elements converted into digital values, said circuit being electrically coupled to the digital converting means, an integrating circuit for successively integrating the values produced by the processing circuit, said circuit being electrically coupled to the processing circuit, a detecting circuit for detecting the maximum value of the value produced by the integrating circuit during the variation of the same in accordance with the movement of the movable part of the photo-taking optical system, said circuit being electrically coupled to the integrating circuit and producing a focusing signal when the maximum value of the integrated value is detected.

30. A camera in accordance with claim 29, further comprising; driving means capable of responsing to the focussing signal produced by the detection circuit and of moving the movable part of the optical system along the optical axis, said means being functionally engaged with the movable part of the optical system and electrically connected with the detecting circuit, so as to move the movable part of the optical system along the optical axis until the detecting circuit produces the focussing signal.

31. A camera in accordance with claim 29, further comprising; indication means for indicating the focussing condition relative to the object to be photographed, of the optical system in accordance with the focussing signal produced by the detecting circuit, said means being electrically connected with the detecting circuit.

32. A camera in accordance with claim 28, said second processing device comprising: an addition circuit for successively adding the outputs of the photoelectric converting elements converted into digital values, said circuit being electrically connected with the digital converting means, a dividing circuit for dividing the values obtained from the addition circuit by the total number of the photoelectric converting elements, said dividing circuit being electrically connected with the addition circuit, a processing circuit for processing the exposure value in accordance with the value obtained from the dividing circuit.

33. A camera in accordance with claim 32, further comprising; indication means for indicating the exposure value on the bases of the value obtained from the processing circuit, said indication means being electrically connected with the processing circuit.

34. A camera in accordance with claim 32, further comprising; exposure adjusting means for adjusting the exposure on the basis of the value obtained from the processing circuit, said adjusting means being electrically connected with the processing circuit.

35. A system capable of .[.either.]. exposure measurement .[.or the.]. and detection of focusing condition of an optical system comprising; a plurality of photoelectric converting elements for converting light beam into electrical signals, each photoelectric converting element producing an electrical output corresponding to a portion of the light beam, .[.sequential sensing.]. time series output means for successively transmitting the outputs of successive ones of the photoelectric converting elements, said .[.sensing.]. time series output means being electrically connected with the photoelectric converting elements, digital converting means for converting the outputs successively transmitted by means of the .[.sensing.]. time series output means, of the photoelectric converting elements into digital values, a processing device for processing the outputs of the photoelectric converting elements converted in digital values by means of the digital converting means .[.either.]. in accordance with a first predetermined estimation function so as to determine a exposure value, .[.or.]. and in accordance with the predetermined second estimation function so as to detect the focusing condition of the optical system, said device being electrically connected with the digital converting means in such a manner that .[.either.]. exposure measurement information .[.or.]. and focusing condition information .[.is.]. are produced by processing the outputs of the photoelectric converting elements converted into digital value in accordance with .[.either of.]. the estimation functions control means for controlling the processing device to operate for either focus detection or exposure measurement.

36. A system capable of either exposure measurement or detection of focusing condition of an image forming optical system at least one part of which is movable along an optical axis so as to form an image of an object at a predetermined position, comprising photoelectric converting means for converting light beam into electrical signals, said means being arranged at the predetermined position and including a plurality of photoelectric converting elements, each element producing an output corresponding to a portion of the input light beam, time series means for making a time series of the outputs of the photoelectric converting elements, said means being electrically connected with the photoelectric means, so as to make the time series of the outputs of the photoelectric converting elements by successively delivering the outputs of the elements one by one, digital converting means for successively converting the time series outputs, of the photoelectric elements into digital values, said means being electrically connected with an output terminal of the photoelectric converting means, a processing device for processing the outputs of the photoelectric converting elements converted in digital values by means of the digital converting means either in accordance with a first predetermined estimation function, so as to determine the exposure value or in accordance with a second predetermined estimation function, so as to detect the focusing condition of the optical system, said device being electrically connected with the digital converting means in such a manner that either the exposure measurement information or information relating with the focusing condition is produced by processing the outputs of the photoelectric converting elements converted into digital values, of the photoelectric converting elements in accordance with either of the estimation functions.[...]., and control means for controlling said processing device, said control means causing the processing device to operate for either the focus detection or exposure measurement.

37. A camera capable of .[.either.]. exposure measurement .].or.]. and detection of focusing condition of image forming optical system by converting the light beam into electrical signal comprising: image sensing means including a plurality of photoelectric converting elements arranged on the same plane, said means being arranged at a position, at which light coming through the optical system can be caught, each photoelectric converting elements producing an output corresponding to a portion of the light, time series means for successively delivering the outputs of the photoelectric converting elements, said means being electrically connected with the image sensing means, digital converting means for successively converting the outputs successively delivered by means of the time series means, of the photoelectric converting elements into digital values, said means being electrically connected with an output terminal of the image sensing means, a processing device for processing the outputs converted in digital value by means of the digital converting means, of the photoelectric converting elements .[.either.]. in accordance with a first predetermined estimation function, so as to determine the exposure value .[.or.]. and in accordance with a second predetermined estimation function, so as to detect the focusing condition of the optical system, said device being electrically connected with the digital converting means, receiving the outputs converted into digital values, of the photoelectric converting elements and producing .[.either.]. exposure measurement information .[.or the estimation functions and information relating with the focusing condition of the photographic optical system by processing the outputs in accordance with .[.either of.]. the estimation functions and control means for controlling the processing device to operate for either focus detection or exposure measurement.

38. For a camera capable of exposure measurement in an optional zone of a photographic scene and having means for setting one or more other exposure factors; an exposure regulating arrangement, comprising; image sensing means including a plurality of photoelectric converting elements regularly arranged on a same plane, said sensing means being arranged at a position in the path of a light beam from the photograhic scene, each of said converting elements producing an electrical signal corresponding to a portion of the light beam, time series means for making a time series of the outputs of said photoelectric converting elements, said time series means being electrically connected with said image sensing means so as to make a time series of the outputs of the converting elements by successively delivering the outputs of the converting elements in accordance with the order of the arrangement of the converting elements, brightness determining means for detecting the brightness of the photographic scene on the basis of the outputs of the photoelectric converting elements, said brightness detecting means being electrically connected with the image sensing means and detecting the brightness of the photographic scene by processing at most all the outputs of the photoelectric converting elements, control means for controlling the detecting operation of said brightness determining means, said control means being operable for causing the brightness determining means to select optional elements whose outputs are to be processed for brightness detection, and exposure determining means for determining an exposure value on the basis of the output of said brightness detecting means and one or more of the other preset exposure factors, said exposure determining means being electrically connected with the brightness detecting means. 39. In a device comprising: sensing means including a plurality of sensing elements, each providing an electrical signal corresponding to radiation energy incident thereon, said sensing means being arranged to receive an image to provide an electrical output corresponding to the radiation energy distribution of the image thereon; and a circuit system responsive to the electrical output of said sensing means to provide an output signal indicative of sharpness of the image on the sensing means; time seriation output means for causing said sensing means to provide as the output thereof the electrical signals of the respective sensing elements in a time-seriated manner; wherein said circuit system includes: first circuit means for receiving the time-seriated output of said sensing means to detect, in a time-seriated manner, variations in the radiation energies between close positions in the image and for providing output signals indicating said variations in a time-seriated manner; and second circuit means receiving the time-seriated output signals of said first circuit menas to detect the sharpness of the image on said sensing means, said second circuit means providing said output signal indicative of the image sharpness on the basis of the time-seriated output signals of the first circuit means and being arranged to provide said output signal indicative of the image sharpness by integrating said variations in the radiation energies on the basis of the time-seriated output signals of said first circuit means. 40. The device according to claim 39, wherein said time seriation output means is pulse controlled means which is operable, in response to supplied control pulses, to feed the electrical signal of each of the sensing elements in said sensing means to said circuit system in a time-seriated manner. 41. The device according to claim 40, wherein said sensing means includes an array of a plurality of addressable sensing elements, and said time seriation output means is address means for addressing, in response to the supplied control pulses and in a time-seriated manner, the respective sensing elements in said sensing means to feed the electrical signal of each of the sensing elements in the sensing means to said circuit system in a time-seriated manner. 42. The device according to claim 39, wherein said first circuit means includes: delay means receiving the time-seriated output of said sensing means and delaying the same for a predetermined time; and detecting means receiving the time-seriated output of the sensing means and the delayed output provided by said delay means and detecting the variation in the radiation energies between each of two close positions in the image on the basis of the and delayed outputs of said sensing means and said delay means, said detecting means providing absolute value signals indicating said variations in a time-seriated manner; and said second circuit means includes; integration means receiving the time-seriated absolute value signals provided by said detecting means in said first circuit means and integrating the absolute value signals to provide said output signal indicative of the image sharpness. 43. A device for detecting sharpness of an image formed by an image forming optical system, comprising: (A) scanning type image sensing means having a plurality of sensing elements, each providing an electrical signal corresponding to radiation energy incident thereon, said sensing means being arranged to receive the image formed by said optical system to provide a time-seriated scanned image signal corresponding to the radiation energy distribution of the image thereon; and (B) a circuit system receiving the time-seriated scanned image signal provided by said sensing means to detect the sharpness of the image on the sensing means, said circuit system including: (B-1) first circuit means receiving said scanned image signal to detect, in a time-seriated manner, variations in the radiation energies between close positions in the image, said first circuit means providing output signals indicating said variations in a time-seriated manner; and (B-2) second circuit means receiving the time-seriated output signals of said first circuit means to detect the sharpness by integrating said variations in the radiation energies of the image on said sensing means, said second circuit means providing an electrical output indicative of the image sharpness on the basis of said time-seriated output signals of the first circuit means. 44. A device according to claim 43, wherein said scanning type image sensing means includes time seriation output means to provide as an output of the sensing means the electrical signals of the respective sensing elements in a time-seriated manner. 45. A device according to claim 44, wherein said time seriation output means is pulse controlled means which is operable, in response to supplied control pulses, to feed the electrical signal of each of the sensing elements to said circuit system in the time-seriated manner. 46. A device according to claim 45, wherein said sensing means has an array of a plurality of addressable sensing elements, and said time seriation output means is address means for addressing, in response to the supplied control pulses and in a time-seriated manner, the respective sensing elements to feed the electrical signal of each of the sensing elements to said circuit system in a time-seriated manner. 47. A device according to claim 43, wherein said first circuit means in said circuit system is so arranged as to detect, in a time-seriated manner, the variations in the radiation energies between each of two close positions in the image, and said second circuit means in said circuit system is so arranged as to provide said electrical output indicative of the image sharpness by integrating said variations in the radiation energies on the basis of the time-seriated output signals of said first circuit means. 48. A device according to claim 47, wherein said first circuit means includes: delay means receiving the time-seriated scanned image signal provided by said sensing means and delaying the same for a predetermined time; and detecting means receiving the time-seriated scanned image signal provided by the sensing means and the delayed output provided by said delay means and detecting the variation in the radiation energies between each of the two close positions in the image on the basis of the and delayed image signals of said sensing means and said delay means, said detecting means providing absolute value signals indicating said variations in a time-seriated manner; and said second circuit means includes: integtration means receiving the time-seriated absolute value signals provided by said detecting means in said first circuit means and integrating the absolute value signals to provide said electrical output indicative of the image sharpness. 49. A device for detecting sharpness of an image formed by an image forming optical system, comprising: sensing means including a plurality of sensing elements, each providing an electrical signal corresponding to radiation energy incident thereon, said sensing means being arranged to receive the image formed by said optical system to provide an electrical output corresponding to radiation energy distribution of the image thereon; a circuit system receiving the electrical output of said sensing means to detect the sharpness of the image on the sensing means, said circuit system including: first circuit means receiving the electrical output of the sensing means to detect variations in the radiation energies between close positions in the image, said first circuit means providing output signals indicating said variations; and second circuit means receiving output signals of said first circuit means to detect the sharpness of the image on said sensing means, said second circuit means providing an output signal indicative of the image sharpness by integrating said variations in the radiation energies on the basis of the output signals of the first circuit means; and time seriation output means for causing said sensing means to provide as the output thereof the electrical signals of the respective sensing elements in a time-seriated manner. 50. The device according to claim 49, wherein said time seriation output means is pulse controlled means which is operable, in response to supplied control pulses, to feed the electrical signal of each of the sensing elements in said sensing means to said circuit system in a time-seriated manner. 51. The device according to claim 50, wherein said sensing means includes an array of a plurality of addressable sensing elements, and said time seriation output means is address means for addressing, in response to the supplied control pulses and in a time-seriated manner, the respective sensing elements in said sensing means to feed the electrical signal of each of the sensing elements in the sensing means to said circuit system in a time-seriated manner. 52. The device according to claim 49, wherein said first circuit means in said circuit system is so arranged as to receive the time-seriated output of said sensing means to detect, in a time-seriated manner, the variations in the radiation energies between the close positions in the image, said first circuit means providing output signals indicating said variations in a time-seriated manner; and second circuit means in said circuit system is so arranged as to receive the time-seriated output signals of said first circuit means to detect the sharpness of the image on said sensing means, said second circuit means providing said output signal indicative of the image sharpness on the basis of the time-seriated output signals of the first circuit means. 53. The device according to claim 52, wherein said second circuit means is so arranged as to provide said output signal indicative of the image sharpness by integrating said variations in the radiation energies on the basis of the time-seriated output signals of said first circuit means. 54. The device according to claim 53, wherein said first circuit means includes: delay means receiving the time-seriated output of said sensing means and delaying the same for a predetermined time; and detecting means receiving the time-seriated output of the sensing means and the delayed output provided by said delay means and detecting the variation in the radiation energies between each of two close positions in the image on the basis of the and delayed outputs of said sensing means and said delay means, said detecting means providing absolute value signals indicating said variations in a time-seriated manner; and said second circuit means includes: integration means receiving the time-seriated absolute value signals provided by said detecting means in said first circuit means and integrating the absolute value signals to provide said output signal indicative of the image sharpness. 55. A device for detecting a focus of an image forming optical system which is adjustable along an optical axis thereof, onto an object, comprising: (A) scanning type image sensing means having a plurality of sensing elements, each providing an electrical signal corresponding to radiation energy incident thereon, said sensing means being arranged to receive an image of the object formed by the optical system to provide a time-seriated scanned image signal corresponding to the radiation energy distribution of the image thereon; and (B) a circuit system receiving the time-seriated scanned image signal provided by said sensing means to detect the focus of said optical system onto the object, said circuit system including: (B-1) first circuit means receiving said scanned image signal to detect, in a time-seriated manner, variations in the radiation energies between close positions in the image, said first circuit means providing output signals indicating said variations in a time-seriated manner; (B-2) second circuit means receiving the time-seriated output signals of said first circuit means to detect the sharpness of the image, said second circuit providing an electrical output by integrating said variations in the radiation energies on the basis of the output signals of the first circuit means, said electrical output having a characteristic by accumulating correlation information on the basis of the output signals of said correlation detecting means when the optical system is properly focused onto the object; and (B-3) third circuit means for detecting whether the output of said second circuit means has the characteristic as the optical system is adjusted along the optical axis. 56. A device according to claim 55, wherein said scanning type image sensing means includes time seriation output means to provide as an output of the sensing means the electrical signals of the respective sensing elements in a time-seriated manner. 57. A device according to claim 56, wherein said time seriation output means is pulse controlled means which is operable, in response to supplied control pulses, to feed the electrical signal of each of the sensing elements to said circuit system in a time-seriated manner. 58. A device according to claim 57, wherein said sensing means has an array of a plurality of addressable sensing elements, and said time seriation output means is address means for addressing, in response to the supplied control pulses and in a time-seriated manner, the respective sensing elements to feed the electrical signal of each of the sensing elements to said circuit system in a time-seriated manner. 59. A device according to claim 55, wherein said first circuit means in said circuit system is so arranged as to detect, in a time-seriated manner, the variations in the radiation energies between each of two close positions in the image, and said second circuit means in said circuit system is so arranged as to provide an electrical output indicative of the image sharpness by integrating said variations in the radiation energies on the basis of the time-seriated output signals of said first circuit means. 60. A device according to claim 59, wherein said sensing means is so arranged as to receive the image of the object formed by the optical system at a position corresponding to a predetermined focal plane of the optical system so that said characteristic output of the second circuit means indicates the maximum image sharpness on said predetermined focal plane. 61. A device according to claim 60, wherein said second circuit means is so arranged as to provide a maximum output as said characteristic output when the image sharpness on said predetermined focal plane reaches maximum, and said third circuit means is so arranged as to detect whether the output of said second circuit means reaches maximum as the optical system is adjusted along the optical axis. 62. A device according to claim 61, wherein said first circuit means includes: delay means receiving the time-seriated scanned image signal provided by said sensing means and delaying the same for a predetermined time; and detecting means receiving the time-seriated scanned image signal provided by the sensing means and the delayed output provided by said delay means and detecting the variation in the radiation energies between each of the two close positions in the image on the basis of the and delayed image signals of said sensing means and said delay means, said detecting means providing absolute value signals indicating said variations in a time-seriated manner; and said second conduit means includes: integration means receiving the time-seriated absolute value signals provided by said detecting means in said first circuit means and integrating the absolute value signals to provide said electrical output indicative of the image sharpness. 63. A system for detecting sharpness of an image formed by an image forming optical system, comprising: (A) scanning type image sensing means having a plurality of sensing elements, each for receiving a different image portion of said image and for providing an electrical signal corresponding to said image portion, said sensing means being arranged to receive the image formed by the optical system to provide as an output indicative of imaging condition of the image the electrical signals of the respective elements in a time-seriated manner; (B) means for detecting, on the basis of the output of said sensing means, correlation between each of two close image portions of the image in a time-seriated manner, said correlation detecting means providing a time-seriated electrical output indicative of the correlation; and (C) means receiving the output of said correlation detecting means and providing a resultant output indicative of the sharpness of the image formed by the optical system in a digital word. 64. In a focusing system, a focus detecting device comprising: (A) sensing means having a plurality of radiation sensitive elements, each providing an electrical signal corresponding to radiation incident thereon, said sensing means being disposed at a position corresponding to at least near a predetermined focal plane on which an image of an object is to be focused, so as to receive radiation distribution which changes with the change in the focusing condition of the focusing system; (B) means for causing said sensing means to provide as an output indicative of said radiation distribution the electrical signals of the respective elements in a time seriated manner; (C) means for detecting, on the basis of the output of said sensing means, correlation of radiation distribution between each of two close positions in said focal plane, said correlation detecting means providing electrical signals indicative of the correlations; and (D) means receiving the electrical signals from said correlation detecting means and providing a resultant output indicative of the focusing condition of the focusing system. 65. A focus detecting device according to claim 64, wherein said correlation detecting means provides each electrical signal indicative of each correlation in a digital word. 66. A focus detecting device according to claim 65, wherein said correlation detecting means provides the electrical signals in a time-seriated manner. 67. A focus detecting device according to one of claim 64 to 66, wherein said resultant output providing means provides the resultant output in a digital word. 68. An exposure measurement system comprising: (A) light sensing means including a plurality of sensing elements, each for receiving a portion of a light and for providing an electrical signal corresponding to said portion of the light; (B) time seriation means for causing said sensing means to provide as an output thereof the electrical signals of the respective sensing elements in a time-seriated manner; and (C) processing means receiving the time-seriated output of said sensing means and processing at most all the electrical signals of said sensing elements to determine an exposure value; and (D) control means for controlling the signal processing operation of said processing means, said control means being operable for causing the processing means to select optional elements whose electrical signals are to be processed for the determination of the exposure value. 69. An exposure measurement system according to claim 68, wherein said processing means determines the exposure value on the basis of the output of said sensing means and one or more other exposure factors. 70. An exposure measurement system according to claim 68 or 69, wherein said processing means provides a resultant output indicative of the determined exposure value in a digital word. 71. A system for exposure measurement and detection of focusing condition of an image forming optical system onto an object, comprising: (A) sensing means including a plurality of sensing elements, each providing an electrical signal corresponding to a portion of a light incident thereon, said sensing means being arranged to receive an image of the object formed by said optical system; (B) time seriation means for causing said sensing means to provide as an output thereof the electrical signals of the respective sensing elements in a time-seriated manner; (C) first processing means receiving the time-seriated output of said sensing means and processing said output to detect the focusing condition of the optical system onto the object; (D) second processing means receiving the time-seriated output of said sensing means and processing said output to determine an exposure value; and (E) sequence control means for controlling operations of said time seriation means and said first and second processing means, said sequence control means firstly causing said time seriation means and one of said first and second processing means to operate for one of said focus detection and exposure determination and after the termination of said one of focus detection and exposure determination causing the time seriation means and the other of said first and second processing means to operate for the other of said focus detection and exposure determination. . A system according to claim 71, wherein said sequence control means firstly causes said first processing means to operate for the focus detection and after the termination of the focus detection by the first processing means causes said second processing device to operate for the exposure determination. 73. A system according to claim 71, wherein said first processing means provides a resultant output indicative of the focusing condition of the optical system in a digital word. 74. A system according to claim 71 or 73, wherein said processing means provides a resultant output indicative of the determined exposure value in a digital word. 75. A system for exposure measurement and detection of focusing condition of an image forming optical system onto an object, comprising: (A) sensing means including a plurality of sensing elements, each providing an electrical signal corresponding to a portion of a light incident thereon, said sensing means being arranged to receive an image of the object formed by said optical system; (B) time seriation means for causing said sensing means to provide an output thereof the electrical signals of the respective sensing elements in a time-seriated manner; (C) processing means receiving the output of said sensing means and processing said output for focus detection and for exposure determination, said processing means being selectively operable in a first operation mode for detection of the focusing condition of the optical system on the basis of said output and in a second operation mode for determining an exposure value on the basis of said output; and (D) sequence control means for controlling operations of said time seriation means and said processing means, said sequence control means firstly causing the time seriation means to operate and the processing means to operate in one of said first and second operation modes for one of said focus detection and exposure determination and after the termination of said one of the focus detection and exposure determination causing again the time seriation means to operate and the processing means to operate in the other of said first and second operation modes for the other of said focus detection and exposure determination. 6. A system according to claim 75, wherein said sequence control means firstly causes said processing means to operate in said first operation mode for the focus detection and after the termination of the focus detection causes the processing means to operate in said second operation mode for the exposure determination. 77. A system according to claim 75 or 76, wherein said processing means provides a first output indicative of the focusing condition of the optical system and a second output indicative of the determined exposure value in digital words. 78. A system capable of either of exposure measurement or detection of focusing condition of an image forming optical system onto an object, comprising: (A) sensing means including a plurality of sensing elements, each providing an electrical signal corresponding to a portion of a light incident thereon, said sensing means being arranged to receive an image of the object formed by said optical system; (B) time seriation means for causing said sensing means to provide as an output thereof the electrical signals of the respective sensing elements in a time-seriated manner; (C) processing means receiving the output of said sensing means and processing said output for either of detecting focusing condition of the optical system or determining an exposure value, said processing means providing focusing condition information or exposure value information on the basis of the output of the sensing means; and (D) control means for controlling said time seriation means and said processing means, said control means causing the time seriation means and the processing means to operate for either of the focus detection or exposure determination. 79. A system according to claim 78, wherein said processing means provides said focusing condition information or exposure value information in a digital word. 80. In a focusing system, a focus detecting device comprising: (A) sensing means having a plurality of radiation sensitive elements, each providing an electrical signal corresponding to radiation incident thereon, said sensing means being disposed at a position corresponding to at least near a predetermined focal plane on which an image of an object is to be focused, so as to receive radiation distribution which changes with the change in the focusing condition of the focusing system; (B) means for causing said sensing means to provide as an output indicative of said radiation distribution the electrical signals of the respective elements in a time seriated manner; (C) means for detecting, on the basis of the output of said sensing means, correlation of radiation distribution between each of two close positions in said focal plane, said correlation detecting means providing electrical signals indicative of the correlation; and (D) means receiving the electrical signal from said correlation detecting means and providing a resulting output indicative of the focusing condition of the focusing system by accumulating correlation information on the basis of the output signals of said correlation detecting means.