Distance detecting device

Abstract

A distance detecting device utilizable in an optical device such as a camera and the like requiring focusing operation of the optical system thereof. The detecting device enables the adjustment of the relative optical length between the group of light receiving elements arranged adjacent to the image forming plane of the object to be measured by the distance measuring optical system and the distance measuring optical system. The detecting device is characterized in that the output of each of the light receiving elements of the groups is introduced through an electric switching device for effecting the time seriation of the outputs of the respective light receiving elements into a common signal processing circuit, so as to adjust the relative optical length by means of a motor provided in responsive relationship to the output of the signal processing circuit thereby permitting the focusing of the image on the groups of the light receiving elements to be made to the most proper condition.

What is claimed is: 
     
       1. A distance detecting device, comprising: a distance measuring optical system for forming an image of an object to be measured;   photoelectric transducer means arranged adjacent to the image forming plane of said distance measuring optical system, for developing electrical signals in response to incident light said transducer means including a plurality of photoelectric transducer elements arranged in juxtaposed relationship to each other;   time seriating means for time seriating the outputs of the respective elements constituting said photoelectric transducer means so as to form time seriated signals;   means for producing a time varying reference signal proportional to the distance to said object;   signal processing means for receiving said time seriated signals and said reference signal and for comparing the time seriated signal and reference signal to generate an output signal corresponding to the condition of focusing of said image of said object; and   focusing degree identifying output means, said means for receiving the output signal from said signal processing circuit for adjusting the relative length of the light path between said distance measuring optical system and said photoelectric transducer means, thereby compensating for the detected condition of the focusing of the image of said object on said photoelectric transducer means formed by said distance measuring optical system so as to detect the distance of said object.     
     
     
       2. A device according to claim 1, wherein said time seriating means comprises electric switching means for coupling the output of the respective elements sucessively to said signal processing means. 
     
     
       3. A device according to claim 1, wherein said focusing degree identifying output means is a motor. 
     
     
       4. A distance detecting device, comprising: a distance detecting optical system for forming an image of an object to be measured;   photoelectric transducer means arranged adjacent to the image forming plane of said distance detecting optical system, for develping electrical signals in response to incident light, said means including a plurality of photoelectric transducer elements each capable of accumulating electric charge corresponding to the quantity of light incident thereto and arranged in juxtaposed relationship to each other;   time seriating means for picking up the electric charged accumulated in said photoelectric transducer means for generating time seriated signals;   means for producing a time varying reference signal proportional to the distance to said object;   signal processing means for receiving said time seriated signals and said reference signal and for comparing the time seriated signal and reference signal to generate an output signal corresponding to the condition of focusing of the image of said object; and   focusing degree identifying output means, said means for receiving the output signal from said signal processing means for adjusting the relative length of the optical path between said distance measuring optical system and said photoelectric transducer means, thereby compensating for the detected condition of the focusing of the image of the object on said photoelectric transducer means formed by said distance measuring optical system so as to detect the distance of the object.     
     
     
       5. A device according to claim 4, wherein said time seriating means is provided with electric switching means for coupling the output of the respective element successively to said signal processing means. 
     
     
       6. A device according to claim 4, wherein said focusing degree identifying output means is a motor. 
     
     
       7. A device according to claim 4, wherein said photoelectric transducer means is a charge coupled device. 
     
     
       8. A device according to claim 4, wherein said photoelectric transducer means is a bucket brigade device. 
     
     
       9. A distance detecting device having a fixed optical system and a movable optical system, said systems having equal focal length and located in spaced relationship from each other in a plane perpendicular to the optical axis and photoelectric transducer means arranged adjacent to a common image forming plane of both of said optical systems so as to photoelectrically measure the distance of an object to be measured, said device comprising: said photoelectric transducer means including a first group of a plurality of photoelectric transducer elements arranged in juxtaposed relationship to each other and aligned with said fixed optical system and a second group of a plurality of photoelectric transducer elements arranged in the same configuration as those of said first group and aligned with said movable optical system;   time seriating means for scanning the elements in said first and second groups so as to time seriate the output signals of said elements to generate the respective time seriated signals; and   a control circuit, said control circuiting including:   a. phase discriminating means for detecting the phase difference in said two series of time seriated signals so as to generate an output signal corresponding to the detected phase difference; and   b. focusing degree identifying output means adapted to receive the output signal from said phase discriminating means for adjusting the relative length of the optical path between said movable optical system and said second group of photoelectric transducer elements, thereby permitting the condition of focusing of the image of the object on said second group of photoelectric elements formed by said movable optical system to be adjusted to an optimum condition.   
     
     
       10. A device according to claim 9, wherein said time seriating means is provided with electric switching means for coupling the output of the respective elements successively to said control circuit. 
     
     
       11. A device according to claim 9, wherein said focusing degree indentifying means is a motor. 
     
     
       12. A device according to claim 9, further comprising a photographing optical system arranged to be actuated in responsive relationship to the output of said focusing degree identifying output means. 
     
     
       13. A distance detecting device having a fixed optical system and a movable optical system said systems having equal focal length and located in spaced relationship from each other in a plane perpendicular to the optical axis and photoelectric transducer means arranged adjacent to a common image forming plane of both of said optical systems so as to photoelectrically measure the distance of an object to be measured, said device comprising: said photoelectric transducer means being comprised of a plurality of elements arranged in juxtaposed relationship to each other;   optical means for focusing images of the object formed by the image bearing light bundles passing through said fixed and movable optical systems, respectively, onto said photoelectric transducer means;   shutter means interposed between said fixed and movable optical systems and said photoelectric transducer means, said means allowing the image-bearing light bundles passing through said fixed optical system and said movable optical system, respectively, to be alternately incident to said photoelectric transducer means;   time seriating means, said means being adapted to scan the respective elements in said group of photoelectric elements so as to convert the output signals obtained by said fixed and movable optical systems into separate two series of time seriated signals; and   a control circuit, said circuit including:   a. phase discriminating means for detecting the phase difference between said separate two series of time seriated signals so as to generate an output signal corresponding to the detected phase difference, and   b. focusing degree identifying output means adapted to receive the output from said phase discriminating means for adjusting the relative length of the light path between said movable optical system and said photoelectric transducer means, thereby permitting the condition of focusing of the image of the object formed by said movable optical system to be adjusted to an optimum condition.     
     
     
       14. A device according to claim 13, wherein said time seriating means is provided with electric switching means for coupling the output of the respective photoelectric elements successively to said control circuit. 
     
     
       15. A device according to claim 13, wherein said focusing degree identifying output means is a motor. 
     
     
       16. A device according to claim 13, further comprising a photographing optical system arranged to be operated in responsive relationship to said focusing degree identifying output means. .Iadd. 
     
     
       17.  A distance detecting device for detecting the distance between the device and an object, comprising: (A) a range finding optical system arranged so as to form two images of said object with relative positional parallax corresponding to the distance to the object;   (B) photoelectrical light receiving means arranged so as to receive said two images formed by the optical system and to provide output signals representative of the relative position of one of the two images with respect to the position of the other image, said light receiving means including a plurality of photosensitive elements each of which provides an electrical signal corresponding to light incident thereon;   (C) time seriating means electrically coupled to said light receiving means for time seriating the electrical signals of the respective photosensitive elements; said light receiving means providing time seriated signals as the output signals thereof through the operation of the time seriating means; and     (D) signal processing means receiving said time seriated output signals of the light receiving means to provide an electrical output representative of the distance between the device and the object. .Iaddend. .Iadd.18. A device according to claim 17, wherein said range finding optical system comprises;   (a) sighting optical means adapted to be aligned to said object so as to form a 1st image of the object at a predetermined position; and   (b) detecting optical means arranged so as to form a 2nd image of the object at a position corresponding to the distance to the object; and wherein said light receiving means is arranged so as to receive said 1st and 2nd images and to provide output signals representative of the relative position of the 2nd image formed by the detecting optical means with respect to the position of said 1st image formed by the sighting     
     
     
        optical means. .Iaddend. .Iadd.19.  A device according to claim 18, wherein said photoelectrical light receiving means includes a 1st group of the photosensitive elements adapted to receive said 1st image formed by the sighting optical means and a 2nd group of the photosensitive elements adapted to receive said 2nd image formed by the detecting optical means. .Iaddend. .Iadd.20. A device according to claim 19, wherein said signal processing means provides said electrical output by comparing the time seriated output signal of the 2nd group of the elements with the time seriated output signal of the 1st group of the elements. .Iaddend. .Iadd.21. A device according to claim 20, wherein said time seriating means simultaneously time seriates the electrical signals of the respective elements in said 1st group and the electrical signals of the 
     
     
        respective elements in said 2nd group. .Iaddend. .Iadd.22.  A device according to claim 21, wherein said time seriating means includes at least an oscillator and a driver circuit which is electrically coupled to the oscillator and said photoelectrical light receiving means for simultaneously driving said 1st and 2nd groups of the elements in a time serial manner. .Iaddend. .Iadd.23. A device according to claim 21, wherein said photoelectrical light receiving means comprises a 1st and a 2nd photodiode arrays each having a plurality of photodiodes, in correspondence to said 1st and 2nd groups of the elements; and wherein said time seriating means is electrically coupled to each of said 1st and 2nd photodiode array so as to simultaneously time seriate the electrical signals of the respective photodiodes in the 1st array and the electrical signals of the respective photodiodes in the 2nd array. .Iaddend. .Iadd.24. A device according to claim 21, wherein said photoelectrical light receiving means comprises a 1st and a 2nd CCDs (Charge Coupled Devices) each having a plurality of electrical charge storing photosensors, in correspondence to said 1st and 2nd groups of the elements;   and wherein said time seriating means is electrically coupled to each of said 1st and 2nd CCDs so as to simultaneously time seriate the electrical charges of the respective photosensors in the 1st CCD and the electrical charges of the respective photosensors in the 2nd CCD. .Iaddend. .Iadd.25. A device according to claim 21, wherein said photoelectrical light receiving means comprises a list and a 2nd BBDs (Bucket Brigade Devices) each having a plurality of electrical charge storing photosensors, in correspondence to said 1st and 2nd groups of the elements;   and wherein said time seriating means is electrically coupled to each of said 1st and 2nd BBDs so as to simultaneously time seriate the electrical charges of the respective photosensors in the 1st BBD and the electrical charges of the respective photosensors in the 2nd BBD. .Iaddend. .Iadd.26. A device according to claim 18, wherein said sighting optical means is adapted as viewing means for viewing said object. .Iaddend. .Iadd.27. A device according to claim 17, wherein said photoelectrical light receiving means is a photodiode array having a plurality of photodiodes each providing an electrical signal corresponding to light incident thereon and arranged in juxtaposed relationship to each other;   and wherein said time seriating means is electrically coupled to the array and time seriates the electrical signals of the respective photodiodes.   
     
     
        .Iaddend. .Iadd.28.  A device according to claim 17, wherein said photoelectrical light receiving means is a CCD (Charge Coupled Device) having a plurality of electrical charge storing photosensors each storing an electrical charge corresponding to light incident thereon and arranged in juxtaposed relationship to each other; and wherein said time seriating means is electrically coupled to the CCD and time seriates the electrical charges of the respective photosensors. .Iaddend. .Iadd.29. A device according to claim 17, wherein said photoelectrical light receiving means is a BBD (Bucket Brigade Device) having a plurality of electrical charge storing photosensors each storing an electrical charge corresponding to light incident thereon and arranged in juxtaposed relationship to each other;   and wherein said time seriating means is electrically coupled to the BBD and time seriates the electrical charges of the respective photosensors. .Iaddend. .Iadd.30. A device according to claim 17, wherein said time seriating means includes at least an oscillator and a driver circuit which is electrically coupled to the oscillator and said photoelectrical light receiving means so as to electrically driving the light receiving means. .Iaddend. .Iadd.31. A distance measuring device for measuring the distance between the device and an object, comprising;   (A) a range finding optical system arranged so as to form two images of said object with relative positional parallax corresponding to the distance to the object, said optical system having at least one movable optical member for varying said relative positional parallax between the two images, and said movable optical member having a plurality of different positions each representing a different object distance;   (B) photoelectrical light receiving means arranged so as to receive said two images and to provide a 1st output signal representative of the position of one of the two images and a 2nd output signal representative of the position of the other image, said light receiving means including a plurality of photo-sensitive elements each providing an electrical signal corresponding to light incident thereon;   (C) time seriating means electrically coupled to said light receiving means for time seriating the electrical signals of the respective photosensitive elements; said light receiving means providing a 1st and a 2nd time seriated signals as said 1st and 2nd output signals thereof through the operation of said time seriating means; and     (D) signal processing means receiving said 1st and 2nd time seriated output signals of the light receiving means to provide an electrical output representative of the relative position of one of said two images with respect to the position of the other image; thereby the distance between the device and the object is indicated by the set position of the movable optical member in the optical system when the relative positions of the two images coincide with each other. .Iaddend.     
     
     
        .Iadd.32.  A device according to claim 31, wherein said range finding optical system comprises; (a) sighting optical means adapted to be aligned to the object so as to form a 1st image of the object at a predetermined position; and   (b) detecting optical means arranged so as to form a 2nd image of the object at a position corresponding to the distance to the object, said detecting optical means including said movable optical member for varying the relative position of the 2nd image with respect to the position of the 1st image; and wherein said photoelectrical light receiving means is arranged so as to receive said 1st and 2nd images and to provide said 1st output signal in response to the position of the 1st image and said 2nd output signal in response to the position of the 2nd image. .Iaddend. .Iadd.33. A device according to claim 32, wherein said photoelectrical light receiving means includes a 1st group of the photosensitive elements adapted to receive said 1st image formed by the sighting optical means and to provide said 1st output signal, and a 2nd group of the photosensitive elements adapted to receive said 2nd image formed by the detecting optical means and to provide said 2nd output signal. .Iaddend. .Iadd.34. A device according to claim 33, wherein said signal processing means provides said electrical output by comparing the time seriated output signal of the 2nd group of the elements with the time seriated output signal of the 1st group of the elements. .Iaddend. .Iadd.35. A device according to claim 34, wherein said time seriating means simultaneously time seriates the electrical signals of the respective elements in said 1st group and the electrical signals of the respective elements in said 2nd group. .Iaddend. .Iadd.36. A device according to claim 35, wherein said photoelectrical light receiving means comprises a 1st and a 2nd photodiode arrays each having a plurality of photodiodes, in correspondence to said 1st and 2nd groups of the elements;     and wherein said time seriating means is electrically coupled to each of said 1st and 2nd photodiode array so as to simultaneously time seriate the electrical signals of the respective photodiodes in the 1st array and the electrical signals of the respective photodiodes in the 2nd array.   
     
     
        .Iaddend. .Iadd.37.  A device according to claim 31, wherein said photoelectrical light receiving means comprises a 1st and a 2nd CCDs (Charge Coupled Devices) each having a plurality of electrical charge storing photosensors, in correspondence to said 1st and 2nd groups of the elements; and wherein said time seriating means is electrically coupled to each of said 1st and 2nd CCDs so as to simultaneously time seriate the electrical charges of the respective photosensors in the 1st CCD and the electrical charges of the respective photosensors in the 2nd CCD. .Iaddend. .Iadd.38. A device according to claim 32, wherein said sighting optical means is adapted as viewing means for viewing said object. .Iaddend. .Iadd.39. A device according to claim 31, wherein said photoelectrical light receiving means is a photodiode array having a plurality of photodiodes each providing an electrical signal corresponding to light incident thereon and arranged in juxtaposed relationship to each other;   and wherein said time seriating means is electrically coupled to the array and time seriates the electrical signals of the respective photodiodes. .Iaddend. .Iadd.40. A device according to claim 31, wherein said photoelectrical light receiving means is a CCD (Charge Coupled Device) having a plurality of electrical charge storing photosensors each storing an electrical charge corresponding to light incident thereon and arranged in juxtaposed relationship to each other;   and wherein said time seriating means is electrically coupled to the CCD and time seriates the electrical charges of the respective photosensors. .Iaddend. .Iadd.41. A device according to claim 31, wherein said time seriating means includes at least an oscillator and a driver circuit which is electrically coupled to the oscillator and said photoelectrical light receiving means so as to electrically driving the light receiving means. .Iaddend. .Iadd.42. A device according to claim 31, further comprising;   adjusting means for adjusting the position of said movable optical member in the optical system in response to the electrical output of said signal processing means;   said signal processing means stopping the adjusting operation of said adjusting means when relative positions of said two images coincide with each other in the adjusting process of said movable optical member. .Iaddend. .Iadd.43. A focus detecting device for detecting the focusing condition of an image forming lens system to an object, said lens system having an optical axis and adjustable along the axis, said device comprising;   (A) a range finding optical system operatively associated with said image forming lens system so as to form two images of said object with relative positional parallax corresponding to the deviation of set position of the lens system from a position at which the lens system is properly focused on the object;   (B) photoelectrical light receiving means arranged so as to receive said two images and to provide a 1st output signal representative of the position of one of the two images and a 2nd output signal representative of the position of the other image, said light receiving means including a plurality of photosensitive elements each providing an electrical signal corresponding to light incident thereon;   (C) time seriating means electrically coupled to said light receiving means for time seriating the electrical signals of the respective photosensitive elements;   said light receiving means providing a 1st and a 2nd time seriated signals at said 1st and 2nd output signals thereof through the operation of said time seriating means; and   (D) signal processing means receiving said 1st and 2nd time seriated output signals of the light receiving means to provide an electrical output representative the deviation of the set position of said image forming lens system to the position at which the lens system is properly focused   
     
     
        on the object. .Iaddend. .Iadd.44.  A device according to claim 43, wherein said range finding optical system comprises; (a) sighting optical means adapted to be aligned to the object so as to form a 1st image of the object at a predetermined position; and   (b) detecting optical means arranged so as to form a 2nd image of the object at a position corresponding to the distance to the object, said detecting optical means having at least one movable optical member operatively connected to said image forming lens system for arraying the relative position of the 2nd image with respect to the position of the 1st image in correspondence to the set position of the lens system along the optical axis; and wherein said photoelectrical light receiving means is arranged so as to receive said 1st and 2nd images and to provide said 1st output signal in response to the position of the 1st image and said 2nd output signal in response to the position of the 2nd image. .Iaddend. .Iadd.45. A device according to claim 44, further comprising;     adjusting means for adjusting the position of said image forming lens system in response to the electrical output of said signal processing means;   said signal processing means stopping the adjusting operation of said adjusting means when relative position of said 2nd image coincides with the position of said 1st image in the adjusting process of the lens   
     
     
        system. .Iaddend. .Iadd.46.  A distance detecting device for detecting the distance between the device and an object, comprising: (a) an optical system arranged to form two images of the object, said images having a relative positional difference which varies at least with the change in the distance between the object and the device;   (b) photoelectrical light receiving means responsive to said two images, said receiving means including a plurality of photosensitive elements, each for providing an electrical signal corresponding to light incident thereon, said elements being arranged to provide output signals corresponding to the received patterns of said images;   (c) time seriating means coupled to said light receiving means for generating two composite output signals corresponding to each image respectively; and   (d) signal processing means responsive to said composite output signals for providing an electrical output signal representative of the relative positional difference between said two images on said receiving means.   
     
     
        .Iaddend. .Iadd.47.  A distance detecting device for detecting the distance between the device and an object, comprising: (a) an optical system arranged to form two images of the object, said images having relative positional difference which varies at least with the change in the distance between the object and the device;   (b) a first array of photoelectrical light sensitive elements, said first array being arranged so that one of said images is incident thereon, each of said elements for developing an electrical output signal corresponding to the intensity of light associated with a corresponding region of said one image;   (c) a second array of photoelectrical light sensitive elements, said second array being arranged so that the other of said images is incident thereon, each of said elements for developing an electrical output signal corresponding to the intensity of light associated with a corresponding region of said other image;   (d) time seriating means coupled to said first and second arrays of the sensitive elements for generating two composite output signals corresponding to each image respectively; and   (e) comprising means for making a comparison of the composite output signal of said first array with the composite output signal of said second array, for providing an electrical output signal representative of the relative positional difference between said two images on said first and second   
     
     
        arrays. .Iaddend. .Iadd.48.  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 two images of an object along different paths, each image having an associated radiation energy intensity distribution, and to provide electrical outputs corresponding to the radiation energy intensity distributions of said two images focused thereon; and circuit means responsive to said electrical outputs of said sensing means to provide an output signal representative of the relative positional difference between said two images on said sensing means;   the improvement further comprising:   time seriating output means for causing said sensing means to provide as the outputs thereof the electrical signals of the respective sensing elements in a time-seriated manner. .Iaddend. .Iadd.49. A distance detecting device for detecting the distance to an object, comprising:   (a) sensing means including a plurality of addressable sensing elements, each providing an electrical signal in response to light incident thereon, said sensing means being arranged to receive first and second images of said object along different paths;   (b) address means cooperating with said sensing means to scan said first and second images focused on the sensing means, said address means addressing, in a time-seriated manner, the respective sensing elements in the sensing means to cause the sensing means to provide as outputs thereof time seriated electrical signals of the respective sensing elements;   said sensing means providing a first time seriated scanning output on said first image and a second time seriated scanning output on said second image through the scanning operation of said address means; and   (c) circuit means responsive to said first and second time seriated scanning outputs of said sensing means to provide an output signal representative of the relative positional difference between said first and second images on said sensing means. .Iaddend. .Iadd.50. A distance detecting device for detecting the distance to an object, comprising:   (a) sensing means including a plurality of sensing elements, each providing an electrical signal corresponding to light incident thereon, said sensing means being arranged to receive first and second images of said object along different paths;   (b) time seriating output means cooperating with said sensing means to scan said first and second images focused on the sensing means, said time seriating output means providing the sensing means with time seriating timing signals for causing the sensing means to provide as outputs thereof the time seriated electrical signals of the respective sensing elements;   said sensing means providing a first time seriated scanning output on said first image and a second time seriated scanning output on said second image in response to said time seriating timing signals provided by said time seriating output means; and   (c) circuit means receiving said first and second time seriated scanning outputs of said sensing means and comparing the first scanning output with the second scanning output to provide an electrical output representative of the relative positional difference between said first and second images on said sensing means. .Iaddend. .Iadd.51. An image comparator, comprising:   (a) radiation sensing means including a plurality of sensing elements, each providing an electrical signal which varies with the intensity of radiation energy impinging upon a radiation receiving surface thereof;   (b) radiation directing means to direct radiations from first and second fields of view to said sensing means;   (c) time seriating output means for causing said sensing means to provide as outputs thereof time seriated electrical signals of the respective sensing elements;   said sensing means providing a first time seriated electrical output related to said first field of view and a second time seriated electrical output related to said second field of view through the time seriating operation of said time seriating output means;   (d) processing circuit means receiving said first and second time seriated electrical outputs of said light sensing means and providing a resultant signal which has a characteristic when the radiations from the first and second fields of view attain a predetermined relationship on said light sensing means; and   (e) means connected to receive said resultant signal and operable to change at least one of the fields of view until the resultant signal is proximate the characteristics. .Iaddend. .Iadd.52. A distance detecting device for detecting the distance to an object, comprising:   (a) photoelectrical sensing means having a plurality of sensing elements, each providing an electrical signal in response to light impinging thereon, said sensing means being arranged to receive first and second images of said object along different paths;   (b) path change-over means for causing said sensing means to receive said first and second images selectively along the respective paths;   (c) time seriating output means for causing said sensing means to provide as outputs thereof time seriated electrical signals of the respective sensing elements;   said sensing means selectively providing a first time seriated scanning output on the first image and a second time seriated scanning output on the second image through the change-over operation of said change-over means and the time seriating operation of said time seriating output means; and   (d) circuit means receiving said first and second time seriated scanning outputs of said sensing means and providing an output signal representative of the relative positional difference between said first   
     
     
        and second images on said sensing means. .Iaddend. .Iadd.53.  A distance detecting device for detecting the distance to an object, comprising: (a) light sensing means having a plurality of sensing elements, each providing an electrical signal in response to light incident thereon, and light sensing means being arranged to receive first and second images of said object along different paths;   (b) path change-over means for causing said light sensing means to receive said first and second images selectively along the respective paths;   (c) time seriating output means for causing said light sensing means to provide as outputs thereof the time seriated electrical signals of the respective sensing elements;   said light sensing means selectively providing a first time seriated scanning output on the first image and a second time seriated scanning output on the second image through the change-over operation of said change-over means and the time seriating operation of said time seriating output means;   (d) first circuit means for receiving said first time seriated scanning output of said light sensing means;   (e) second circuit means for receiving said second time seriated scanning output of said light sensing means;   (f) output directing means to direct said first scanning output to said first circuit means and said second scanning output to said second circuit means each respectively; and   (g) comparison means receiving said first and second scanning outputs through said first and second circuit means and comparing the first scanning output with the second scanning output to provide an output signal representative of the relative positional difference between said first and second images on said sensing means. .Iaddend. .Iadd.54. An image comparator, comprising:   (a) light sensing means having a plurality of sensing elements, each providing an electrical signal which varies with the change in the intensity of light impinging upon a light receiving surface thereof;   (b) light directing means to direct light from first and second fields of view to said light sensing means;   (c) light path change-over means for causing said light sensing means to receive the light from said first and second fields of view selectively through said light directing means;   (d) time seriating output means for causing said light sensing means to provide as outputs thereof the time seriated electrical signals of the respective sensing elements;   said light sensing means selectively providing a first time seriated electrical output related to said first field of view and a second time seriated electrical output related to said second field of view through the change-over operation of said light path change-over means and the time seriating operation of said time seriating output means;   (e) processing circuit means receiving said first and second time seriated electrical outputs of said light sensing means and providing a resultant signal which has a charcteristic when the lights from the first and second fields of view attain a predetermined relationship on said light sensing means; and   (f) means connected to receive said resultant signal and operable to change at least one of the fields of view until the resultant signal is proximate   
     
     
        the characteristic. .Iaddend. .Iadd.55.  The improvement as in claim 48, wherein said time seriating output means is means for providing said sensing means with time seriating timing signals to cause the sensing means to provide as the outputs thereof the time seriated electrical signals of the respective sensing elements; said sensing means provides time seriated electrical signals on the radiation energy intensity distributions of said two images in response to said time seriating timing signals provided by said time seriating output means. .Iaddend. .Iadd.56. The improvement as in claim 48, wherein said sensing means includes a plurality of addressable sensing elements, and said time seriating output means is address means for addressing, in time-seriated manner, the respective sensing elements in the sensing means to cause the sensing means to provide as the outputs thereof the time seriated electrical signals of the respective sensing elements. .Iaddend. .Iadd.57. The improvement as in claim 48, wherein said time seriating 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 means in a time-seriated manner. .Iaddend. .Iadd.58. A system, comprising:   image forming means for receiving energy from a source along two paths and forming two images of the source;   a receiving arrangement having a plurality of sensing elements, said elements being arranged to receive energy of a plurality of portions of one of the images and of a plurality of portions of the other of the images and to produce two sets of electrical signals, each signal being in response to a characteristic of the energy at an element;   scanning means coupled to the receiving arrangement for sequentially sampling the signals in each of the two sets to produce a time-seriating output for each set; and   comparing means for comparing the two outputs to produce indications indicative of the relative positional difference between the two images on the receiving arrangement. .Iaddend. .Iadd.59. A system as in claim 58, wherein said image forming means includes:   a first image forming device for forming the first image of the source,   a second image forming device spaced from the first image forming device for forming the second image. .Iaddend. .Iadd.60. A system as in claim 58, wherein said image forming means, said receiving arrangement, and said scanning means form a detector, said system further comprising:   feedback means coupling said comparing means to said detector for varying one of the sets of said time-seriating outputs. .Iaddend. .Iadd.61. A system as in claim 59, wherein said image forming means, said receiving arrangement, and said scanning means form a detector, said system further comprising:   feedback means coupling said comparing means to said detector for varying one of the sets of said time-seriating outputs. .Iaddend. .Iadd.62. A system as in claim 58, further comprising:   feedback means coupled to the comparing means and said image forming means for varying one of the sets of the time-seriating outputs. .Iaddend. .Iadd.63. A system as in claim 59, further comprising:   feedback means coupled to the comparing means and one of the image forming devices for changing the relative positions of the image forming devices to vary one of the sets of the time-seriating outputs. .Iaddend. .Iadd.64. A system as in claim 60, further comprising:   a body defining a focusing plane, and   an objective device for focusing an image of the source onto the focusing plane,   said feedback means being connected to said objective device for moving the objective device toward a focused position in response to indications provided by said comparing means. .Iaddend. .Iadd.65. A system as in claim 62, further comprising:   a body defining a focusing plane, and   an objective device for focusing an image of the source onto the focusing plane,   said feedback means being connected to said objective device for moving the objective device toward a focused position in response to indications provided by said comparing means. .Iaddend. .Iadd.66. A system as in claim 58, wherein:   said elements are arranged in two arrays, each in the path of one of the images, and   wherein said scanning means separately scans each of the two arrays. .Iaddend. .Iadd.67. A system as in claim 59, wherein said elements are arranged in two arrays, each in the path of one of the images, and   wherein said scanning means separately scans each of the two arrays.   
     
     
        .Iaddend. .Iadd.68.  A system as in claim 60, wherein said elements are arranged in two arrays, each in the path of one of the images, and wherein said scanning means separately scans each of the two arrays. .Iaddend. .Iadd.69. A system as in claim 61, wherein said elements are arranged in two arrays, each in the path of one of the images, and wherein said scanning means separately scans each of the two arrays. .Iaddend. .Iadd.70. A system as in claim 62, wherein said elements are arranged in two arrays, each in the path of one of the images, and   wherein said scanning means separately scans each of the two arrays. .Iaddend. .Iadd.71. A system as in claim 63, wherein said elements are arranged in two arrays, each in the path of one of the images, and   wherein said scanning means separately scans each of the two arrays. .Iaddend. .Iadd.72. A system as in claim 64, wherein said elements are arranged in two arrays, each in the path of one of the images, and   wherein said scanning means separately scans each of the two arrays. .Iaddend. .Iadd.73. A system as in claim 65, wherein said elements are arranged in two arrays, each in the path of one of the images, and   wherein said scanning means separately scans each of the two arrays.   
     
     
        .Iaddend. .Iadd.74.  A system as in claim 58, wherein: said elements are arranged in an array, and   said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans with each other. .Iaddend. .Iadd.75. A system as in claim 59, wherein:   said elements are arranged in an array, and said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans with each other. .Iaddend. .Iadd.76. A system as in claim 60, wherein:   said elements are arranged in an array, and said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans   
     
     
        with each other. .Iaddend. .Iadd.77.  A system as in claim 61, wherein: said elements are arranged in an array, and said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans with each other. .Iaddend. .Iadd.78. A system as in claim 62, wherein:   said elements are arranged in an array, and said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans with each other. .Iaddend. .Iadd.79. A system as in claim 63, wherein:   said elements are arranged in an array, and said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans   
     
     
        with each other. .Iaddend. .Iadd.80.  A system as in claim 64, wherein: said elements are arranged in an array, and said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans with each other. .Iaddend. .Iadd.81. A system as in claim 64, wherein:   said elements are arranged in an array, and said arrangement includes alternating means for alternately applying the energy of each of the images onto the array, and said scanning means first scans the array when it receives one image, and then scans the array when it receives the other image,   said comparing means includes means for comparing the alternating scans with each other. .Iaddend.