Automatic focus state detecting apparatus

Claim 2

An automatic focus state detecting appa­ratus, comprising: focus state detecting means for effecting focus state detection respectively in a narrow focus state detecting area and a wide focus state detecting area present in the object field; discrimination means for discriminating whether an object present in either of said focus state detect­ing area is moving; and selection means for causing, when said object is identified as moving by said discrimination means, said focus state detecting means to effect said focus state detection in said wide focus state detecting area.

Claim 3

An apparatus according to claim 1, wherein said selection means is adapted, when said object is identified as not moving by said discrimination means, to cause said focus state detecting means to effect the focus state detection in said narrow focus state detecting area.

Claim 4

An apparatus according to claim 1 or 2, further comprising: area mode selection means for manually select­ing either to cause said focus state detecting means to effect the focus state detection in said wide focus state detecting area, or to cause said focus state detecting means to effect the focus state detec­tion in said narrow focus state detecting area.

Claim 5

An automatic focus state detecting appa­ratus, comprising: photoelectric conversion means for converting an image of the object formed by light transmitted by a photographing lens into electrical signals in successive manner; defocus amount calculating means for calculating, in repetitive manner, a defocus amount correspond­ing to the distance between an image plane on which the image of said object is formed and a predeter­mined focal plane, based on the electrical signals released in successive manner from said photoelectric conversion means; selection means for selecting either a narrow focus state detecting area or a wide focus state detecting area present in the object field, and for causing said defocus amount calculating means to cal­culate the defocus amount of an object present in said narrow focus state detecting area upon selec­tion thereof, or to calculate the defocus amount of an object present in said wide focus state detecting area upon selection thereof; and discrimination means for discriminating whether said object is moving; wherein said selection means is adapted to auto­matically select said wide focus state detecting area when said discrimination means identifies the movement of said object.

Claim 6

An automatic focus state detecting appa­ratus, comprising: photoelectric conversion means for converting an image of the object formed by light transmitted by a photographing lens into electrical signals in successive manner; defocus amount calculating means for calculating, in repetitive manner, a defocus amount correspond­ing to the distance between an image plane on which the image of said object is formed and a predeter­mined focal plane, based on the electrical signals released in successive manner from said photoelectric conversion means; selection means for selecting either a narrow focus state detecting area or a wide focus state detecting area present in the object field, and for causing said defocus amount calculating means to cal­culate the defocus amount of an object present in said narrow focus state detecting area upon selec­tion thereof, or to calculate the defocus amount of an object present in said wide focus state detecting area upon selection thereof; and discrimination means for discriminating whether said object is moving; wherein said selection means is adapted to auto­matically select said wide focus state detecting area when said discrimination means identifies the movement of said object.

Claim 7

An apparatus according to claim 4, wherein said selection means is adapted to automatically select said narrow focus state detecting area when said discrimination means identifies the stopped state of said object.

Claim 8

An apparatus according to claim 4 or 5, wherein said discrimination means is adapted to dis­criminate the movement of said object, based on said repetitively calculated defocus amounts.

Claim 9

An apparatus according to claim 4 or 5, further comprising: area mode selection means for manually selecting either to cause said defocus amount calculating means to effect the focus state detection on an object in said wide focus state detecting area, or to cause said defocus amount calculating means to effect the focus state detection on an object in said narrow focus state detecting area.

Claim 10

An automatic focus state detecting appa­ratus, comprising: photoelectric conversion means for converting an image of the object formed by light transmitted by a photographing lens into electrical signals in successive manner; defocus amount calculating means for calculating, in repetitive manner, a defocus amount correspond­ing to the distance between an image plane on which the image of said object is formed and a predeter­mined focal plane, based on the electrical signals released in successive manner from said photoelectric conversion means; discrimination means for discriminating whether said object is moving, based on the defocus amount repetitively released from said defocus amount calcu­lating means; selection means capable of selecting a wide focus state detecting area or a narrow focus state detecting area present in the object field, and for causing said defocus amount calculating means to calculate the defocus amount on an object in said wide focus state detecting area when said discrimination means identifies the movement of said object; correction means for predicting the change in the defocus amount resulting from the movement of the object, based on the defocus amount repetitively released from said defocus amount calculating means, and correcting the defocus amount released from said defocus amount calculating means in consideration of the predicted change; and drive amount calculating means for calculating the drive amount of said photographing lens, based on the defocus amount corrected by said correction means.

Claim 11

An automatic focus state detecting appa­ratus, comprising: photoelectric conversion means for converting an image of the object formed by light transmitted by a photographing lens into electrical signals in successive manner; defocus amount calculating means for calculating, in repetitive manner, a defocus amount correspond­ing to the distance between an image plane on which the image of said object is formed and a predeter­mined focal plane, based on the electrical signals released in successive manner from said photoelectric conversion means; discrimination means for discriminating whether said object is moving, based on the defocus amount repetitively released from said defocus amount calcu­lating means; selection means capable of selecting a wide focus state detecting area or a narrow focus state detecting area present in the object field, and for causing said defocus amount calculating means to calculate the defocus amount on an object in said wide focus state detecting area when said discrimination means identifies the movement of said object; correction means for predicting the change in the defocus amount resulting from the movement of the object, based on the defocus amount repetitively released from said defocus amount calculating means, and correcting the defocus amount released from said defocus amount calculating means in consideration of the predicted change; and drive amount calculating means for calculating the drive amount of said photographing lens, based on the defocus amount corrected by said correction means.

Claim 12

An apparatus according to claim 8, wherein said selection means is adapted to cause said defocus amount calculating means to calculate the defocus amount on an object in said narrow focus state detect­ing area when said discrimination means identifies the stepped state of said object.

Claim 13

An apparatus according to claim 8 or 9, further comprising: area mode selection means for manually selecting either to cause said defocus amount calculating means to calculate the defocus amount on an object in said wide focus state detecting area, or to cause said defocus amount calculating means to calculate the defocus amount on an object in said narrow focus state detecting area.

Claim 14

An apparatus according to claim 8, 9 or 10, wherein: said discrimination means is adapted to identify said object as moving when the change in the defocus amount repetitively released from said defocus amount calculating means exceeds a predetermined range; and said selection means is adapted, when said wide focus state detecting area is selected, to divide said wide focus state detecting area into plural small areas, to cause said defocus amount calculating means to calculate the defocus amount in each of said small areas, and to adopt one with smallest absolute value from the calculated defocus amounts.

Claim 15

An apparatus according to claim 8, 9 or 10, wherein said discrimination means is adapted to identify said object as moving, when the change in the defocus amount repetitively released from said defocus amount calculating means exceeds a, pre­determined range and when the camer is not in a con­tinuous photographing operation.

Claim 16

An apparatus according to claim 8, 9 or 10, further comprising focusing mode selection means for manually selecting whether or not to acti­vate said discrimination means.

Claim 17

An apparatus according to claim 13, wherein said focusing mode selection means is adapted, upon selecting a focusing mode to activate said dis­crimination means, to activate said selection means in preference to the function of said area mode selec­tion means, thereby causing to switch said two focus state detecting areas according to the result of dis­crimination by said discrimination means.

Claim 18

An apparatus according to claim 13, wherein said focusing mode selection means is adapted, upon selecting a focusing mode not activating said discrimination means, to activate said area mode selection means in preference to the function of said selection means.

Claim 19

An automatic focus state detecting appa­ratus, comprising: focus state detecting means capable of effect­ing focus state detection in each of plural focus state detecting areas of different sizes present in the object field; displacement detection means for detecting the displacement of a photographing optical system or the relative displacement between the photographing optical system and the object; and switching means for causing said focus state detecting means to effect the focus state detection by switching said plural focus state detecting areas of different sizes, according to the result of dis­placement detection by said displacement detection means.

Claim 20

An automatic focus state detecting appa­ratus, comprising: focus state detecting means capable of effect­ing focus state detection in each of plural focus state detecting areas of different sizes present in the object field; displacement detection means for detecting the displacement of a photographing optical system or the relative displacement between the photographing optical system and the object; and switching means for causing said focus state detecting means to effect the focus state detection by switching said plural focus state detecting areas of different sizes, according to the result of dis­placement detection by said displacement detection means.

Claim 21

An apparatus according to claim 16, wherein said switching means is adapted, in response to an output indicating the detection of a displace­ment from said displacement detection means, to switch the current focus state detecting area to a wider focus state detecting area.

Claim 22

An apparatus according to claim 16 or 17, further comprising: a focus state detecting optical system for form­ing an image of the object; and photoelectric conversion means composed of plural photosensor elements and generating object image sig­nals corresponding to the light intensity distribu­tion of said object image in said plural focus state detecting areas; wherein said focus state detecting means is adapted to effect the focus state detection by apply­ing a predetermined calculation on said object image signals.

Claim 23

An apparatus according to claim 18, wherein said displacement detection means is adapted to detect the displacement by comparing the object image signals from said photoelectric conversion means at different times.

Claim 24

An apparatus according to claim 19, wherein said displacement detection means is adapted to detect the displacement by comparing said object image signals of different times by correlation calcu­lation.

Claim 25

An apparatus according to claim 19, wherein: said photoelectric conversion means is composed of photosensor arrays arranged in mutually perpendicu­lar two directions in the object field; and said displacement detection means is adapted to detect the displacement in said two directions, based on the object image signals from said photosen­sors.

Claim 26

An apparatus according to claim 16 or 17, further comprising: a photographing optical system for forming an image of the object on a predetermined plane; a focus state detecting optical system for forming an image of the object by a light beam transmitted by said photographing optical system; and photoelectric conversion means composed of plural photosensor elements and adapted to generate object image signals corresponding to the light intensity distribution of said object image; wherein said focus state detecting means is adapted to detect the defocus amount of the current object image plane with respect to said predetermined plane, by applying a predetermined calculation on said object image signals.

Claim 27

An apparatus according to claim 22, wherein said displacement detecting means is adapted to detect the displacement, based on the change in time of said defocus amount.

Claim 28

An apparatus according to claim 23, wherein said displacement detection means detects the presence of displacement, after a defocus amount close to the in-focus state is obtained in the calcu­lation by said focus state detecting means, when the absolute value of the defocus amount calculated by said focus state detection means exceeds a pre­determined value.

Claim 29

An apparatus according to claim 16 or 17, wherein said displacement detection means comprises a sensor for detecting the displacement of the camera and is adapted to detect the displacement based on the output of said sensor.

Claim 30

An apparatus according to claim 25, wherein said displacement detection means is adapted to detect the displacement, based on the output of said sensor integrated over a predetermined time or during a focus state detecting cycle of said focus state detecting means.

Claim 31

An apparatus according to claim 16 or 17, wherein said displacement detecting means is also adapted to detect the direction of the relative dis­placement between the photographing optical system and the object.

Claim 32

An apparatus according to claim 27, wherein said switching means is adapted to switch said plural focus state detecting means, according to the direction of displacement detected by said detection means.

Claim 33

An apparatus according to claim 28, further comprising: a focus state detecting optical system for form­ing an image of the object; and photoelectric conversion means composed of plural photosensor elements and adapted for generating object image signals corresponding to the light intensity distribution of said object image in said plural focus state detecting areas; wherein said focus state detecting means is adapted to effect the focus state detection by apply­ing a predetermined calculation on said object image signals; and said displacement detecting means is adapted to detect the displacement and the direction thereof, based on the output of said photoelectric conversion means.

Claim 34

An apparatus according to claim 29 wherein: said photoelectric conversion means in a one-­dimensional image sensor having plural areas corres­ponding to said plural focus state detecting areas; and said displacement detection means is adapted to the direction of displacement along the direction of array of said image sensor, thereby switching said areas of said image sensor.

Claim 35

An apparatus according to claim 16 or 17, wherein said displacement detection means is adapted to detect the displacement in the vertical and horizontal directions of the object field.

Claim 36

An automatic focus state detecting appa­ratus, comprising: focus state detecting means comprising a first photoelectric converting element array composed of plural photoelectric converting elements arranged along a particular direction, and a second photoelec­tric converting element array composed of plural photoelectric converting elements arranged along a direction different from said particular direction, and adapted to effect the focus state detection by detecting the position of object images on said first or second photoelectric converting element array; displacement detecting means for detecting the displacement of the automatic focus state detecting apparatus itself or the relative displacement between said focus state detecting apparatus and the object; and selection means for selecting either the outputs of said first photoelectric element array or the out­puts of said second photoelectric element array accord­ing to the detection output of said displacement detect­ing means, and causing said focus state detecting means to effect the focus state detection.

Claim 37

An automatic focus state detecting appa­ratus, comprising: focus state detecting means comprising a first photoelectric converting element array composed of plural photoelectric converting elements arranged along a particular direction, and a second photoelec­tric converting element array composed of plural photoelectric converting elements arranged along a direction different from said particular direction, and adapted to effect the focus state detection by detecting the position of object images on said first or second photoelectric converting element array; displacement detecting means for detecting the displacement of the automatic focus state detecting apparatus itself or the relative displacement between said focus state detecting apparatus and the object; and selection means for selecting either the outputs of said first photoelectric element array or the out­puts of said second photoelectric element array accord­ing to the detection output of said displacement detect­ing means, and causing said focus state detecting means to effect the focus state detection.

Claim 38

An apparatus according to claim 32, wherein said displacement detecting means is adapted to detect the displacement of said automatic focus state detecting apparatus itself or the relative dis­placement between said focus state detecting apparatus and the object, based on the outputs of said first and second photoelectric converting element arrays.

Claim 39

An apparatus according to claim 32 or 33, wherein said selection means is adapted, based on the output of said displacement detecting means, to select the output of one of said first and second photoelectric converting element arrays, in which the displacement of the object image is smaller.

Claim 40

An apparatus according to claim 32, wherein said particular direction and said different direction are mutually perpendicular.

Claim 41

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing optical system for focusing; first focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a relative narrow first focus state detecting area defined in the photographing frame; second focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a second focus state detecting area defined in the photographing frame and wider than said first focus state detecting area; selection means for selecting either said first or second focus state detecting means; drive control means for controlling the drive amount of said drive means according to the defocus amount detected by said focus state detecting means; and limiting means for limiting the defocus amount to be detected or the drive amount of the lens, when said second focus state detecting means is selected by said selection means.

Claim 42

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing optical system for focusing; first focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a relative narrow first focus state detecting area defined in the photographing frame; second focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a second focus state detecting area defined in the photographing frame and wider than said first focus state detecting area; selection means for selecting either said first or second focus state detecting means; drive control means for controlling the drive amount of said drive means according to the defocus amount detected by said focus state detecting means; and limiting means for limiting the defocus amount to be detected or the drive amount of the lens, when said second focus state detecting means is selected by said selection means.

Claim 43

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing opti­cal system for focusing; first focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a relatively narrow first focus state detecting area defined in the photographing frame; second focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a second focus state detecting area defined in the photographing frame and wider than said first focus state detecting area; discrimination means for discriminating, based on said defocus amount, whether the photographing optical system is in an in-focus position and in the vicinity thereof; selection means for selecting the first focus state detecting means until said discrimination means identifies the in-focus position or the vicinity thereof, and selecting the second focus state detect­ing means after said discrimination means identifies said in-focus position or the vicinity thereof; and drive control means for controlling the drive amount of said drive means, according to the defocus amount detected by said focus state detecting means.

Claim 44

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing opti­cal system for focusing; first focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a relatively narrow first focus state detecting area defined in the photographing frame; second focus state detecting means for detecting the defocus amount of the image plane of said photo­graphing optical system with respect to said predeter­mined plane, in a second focus state detecting area defined in the photographing frame and wider than said first focus state detecting area; discrimination means for discriminating, based on said defocus amount, whether the photographing optical system is in an in-focus position and in the vicinity thereof; selection means for selecting the first focus state detecting means until said discrimination means identifies the in-focus position or the vicinity thereof, and selecting the second focus state detect­ing means after said discrimination means identifies said in-focus position or the vicinity thereof; and drive control means for controlling the drive amount of said drive means, according to the defocus amount detected by said focus state detecting means.

Claim 45

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing opti­cal system for focusing; first focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a relative narrow first focus state detecting area defined in the photographing frame; second focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a second focus state detect­ing area defined in the photographing frame and wider than said first focus state detecting area; selection means for selecting the second focus state detecting means after the lapse of a predeter­mined time from the selection of said first focus state detecting means; and drive control means for controlling the drive amount of said drive means, according to the defocus amount detected by said focus state detecting means.

Claim 46

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing opti­cal system for focusing; first focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a relative narrow first focus state detecting area defined in the photographing frame; second focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a second focus state detect­ing area defined in the photographing frame and wider than said first focus state detecting area; selection means for selecting the second focus state detecting means after the lapse of a predeter­mined time from the selection of said first focus state detecting means; and drive control means for controlling the drive amount of said drive means, according to the defocus amount detected by said focus state detecting means.

Claim 47

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing opti­cal system for focusing; first focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a relatively narrow first focus state detecting area defined in the photo­graphing frame; second focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a second focus state detecting area defined in the photographing frame and wider than said first focus state detecting area; selection means for selecting said second focus state detecting means after the focus state detections of a predetermined number from the selection of said first focus state detecting means; and drive control means for controlling the drive amount of said drive means, according to the defocus amount detected by said focus state detecting means.

Claim 48

An automatic focus state detecting appa­ratus, comprising: a photographing optical system for forming an image of the object on a predetermined plane; drive means for driving said photographing opti­cal system for focusing; first focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a relatively narrow first focus state detecting area defined in the photo­graphing frame; second focus state detecting means for repetitively detecting the defocus amount of the image plane of said photographing optical system with respect to said predetermined plane, in a second focus state detecting area defined in the photographing frame and wider than said first focus state detecting area; selection means for selecting said second focus state detecting means after the focus state detections of a predetermined number from the selection of said first focus state detecting means; and drive control means for controlling the drive amount of said drive means, according to the defocus amount detected by said focus state detecting means.

Claim 49

An apparatus according to claim 38 or 39, wherein said selection means is adapted to select said second focus state detecting means if the detec­tion of the defocus amount is identified not possible even before the completion of focus state detections of said predetermined number or before the lapse of said predetermined time.

Claim 50

An apparatus according to claim 38 or 39, wherein said predetermined time or said predetermine number is variable.

Claim 51

An apparatus according to claim 37, 38 or 39, further comprising limiting means for limiting the defocus amount to be detected or the drive amount of the lens, when said second focus state detecting means is selected by said selection means.

Claim 52

An apparatus according to claim 36 or 42, wherein said limiting means is adapted to vary said defocus amount or said lens drive amount to be limited, according to the photographing image magnification.

Claim 53

An apparatus according to claim 37, 38 or 39, wherein said selection means is adapted to select the first focus state detecting means imme­diately after the transition from an unoperated state to a preparatory state of a releasing member which can assume at least an unoperated state, a preparatory state (half-pushed) and a releasing state (full-pushed).

Claim 54

An automatic focusing camera capable of moving a photographing lens automatically to an in-­focus state, comprising: focus state detecting means for detecting the focus adjustment state of said photographing lens and releasing an in-focus signal when said photograph­ing lens reaches an in-focus state; lens drive means for moving said photographing lens to the in-focus state based on the output of said focus state detecting means; exposure control means for effecting an exposure operation; a releasing member for starting the function of said focus state detecting means and said lens drive means in a first-step operation, and generating a release signal for initiating the exposure operation by a second-step operation; discrimination means for starting time measure­ment in response to the first-step operation of said releasing member, and discriminating whether the release signal is generated before the lapse of a predetermined time; and release control means for activating said exposure control means when both said in-focus signal and said release signal are generated, and also activating said exposure control means regardless of the presence or absence of said in-focus signal if said release signal is generated before the lapse of said pre­determined time.

Claim 55

An automatic focusing camera capable of moving a photographing lens automatically to an in-­focus state, comprising: focus state detecting means for detecting the focus adjustment state of said photographing lens and releasing an in-focus signal when said photograph­ing lens reaches an in-focus state; lens drive means for moving said photographing lens to the in-focus state based on the output of said focus state detecting means; exposure control means for effecting an exposure operation; a releasing member for starting the function of said focus state detecting means and said lens drive means in a first-step operation, and generating a release signal for initiating the exposure operation by a second-step operation; discrimination means for starting time measure­ment in response to the first-step operation of said releasing member, and discriminating whether the release signal is generated before the lapse of a predetermined time; and release control means for activating said exposure control means when both said in-focus signal and said release signal are generated, and also activating said exposure control means regardless of the presence or absence of said in-focus signal if said release signal is generated before the lapse of said pre­determined time.

Claim 56

An automatic focusing camera, comprising: a photographing optical system for forming an image of the object on a predetermined plane; a focus state detecting optical system for form­ing an image of the object by a light beam transmitted by said photographing optical system; photoelectric conversion means composed of plural photosensor elements and adapted for generating object image signals corresponding to the light intensity distribution of said object image; focus state detecting/calculating means for detecting the current defocus amount of the image plane of the object with respect to said predeter­mined plane, by applying a predetermined calculation on said object image signals; and means for dividing the focus state detecting area on said photoelectric conversion means into plural small areas, causing said focus state detect­ing/calculating means to detect the defocus amount in each of said small areas, and finally selecting a defocus amount from obtained plural defocus amounts based on the reliabilities thereof.

Claim 57

An automatic focusing camera, comprising: a photographing optical system for forming an image of the object on a predetermined plane; a focus state detecting optical system for form­ing an image of the object by a light beam transmitted by said photographing optical system; photoelectric conversion means composed of plural photosensor elements and adapted for generating object image signals corresponding to the light intensity distribution of said object image; focus state detecting/calculating means for detecting the current defocus amount of the image plane of the object with respect to said predeter­mined plane, by applying a predetermined calculation on said object image signals; and means for dividing the focus state detecting area on said photoelectric conversion means into plural small areas, causing said focus state detect­ing/calculating means to detect the defocus amount in each of said small areas, and finally selecting a defocus amount from obtained plural defocus amounts based on the reliabilities thereof.

Claim 58

A TTL focus state detecting apparatus, comprising: a focus state detecting optical system, composed of a condenser lens position at a film plane or a plane conjugate therewith; and a pair of separator lenses for re-imaging a primary image, formed on said film plane or said conjugate plane, to form secondary images; means for varying the detecting angle of said focus state detecting optical system between two states of large and small detecting angles; discrimination means for discriminating whether the focus state detection is possible when said large detecting angle is selected by said varying means; and control means for varying said focus state detect­ing optical system to the state of small detecting angle, when said discrimination means identifies that the focus state detection is not possible at said large detecting angle.

Claim 59

A TTL focus state detecting apparatus, comprising: a focus state detecting optical system, composed of a condenser lens position at a film plane or a plane conjugate therewith; and a pair of separator lenses for re-imaging a primary image, formed on said film plane or said conjugate plane, to form secondary images; means for varying the detecting angle of said focus state detecting optical system between two states of large and small detecting angles; discrimination means for discriminating whether the focus state detection is possible when said large detecting angle is selected by said varying means; and control means for varying said focus state detect­ing optical system to the state of small detecting angle, when said discrimination means identifies that the focus state detection is not possible at said large detecting angle.

Claim 60

An apparatus according to claim 47, wherein: said focus state detecting optical system further comprises a diaphragm mask positioned in the vicinity of the separator lenses and at least a pair of photo­electric conversion means position on the plane of the secondary images; and said varying means is adapted to switch the detect­ing angle by varying the shape of said diaphragm mask.

Claim 61

An apparatus according to claim 48, wherein: said diaphragm mask is composed of an electro­chromic device; and said varying means is adapted to vary the detecting angle by varying the apertures of said electrochromic device.

Claim 62

A focus state detecting apparatus comprising: a photosensor array composed of plural cells for generating object image signals corresponding to the luminance of an object; focus state detecting-calculating means for detecting the focus state by applying a predetermined calculation on said object image signals; and means for varying the width of a photoelectric conversion area on said cells, in a direction per­pendicular to the direction of said photosensor array.

Claim 63

A focus state detecting apparatus comprising: a photosensor array composed of plural cells for generating object image signals corresponding to the luminance of an object; focus state detecting-calculating means for detecting the focus state by applying a predetermined calculation on said object image signals; and means for varying the width of a photoelectric conversion area on said cells, in a direction per­pendicular to the direction of said photosensor array.

Claim 64

An apparatus according to claim 50, wherein: each of said cells comprises a predetermined number of photoelectric conversion elements, and gates provided between said photoelectric conversion elements; and said varying means is adapted to vary the width of the photoelectric conversion area of said cell by controlling the potential of said gates.

Claim 65

A focus state detecting apparatus compri­sing: focus state detecting means provided with an oblong focus state detecting area positioned on the object field and crossing the optical axis of said focus state detecting optical system, for effecting the focus state detection with the light beam from the object; and auxiliary light emission means for focus state detection, provided in a plane defined by said optical axis of said focus state detecting optical system and a line contained in said focus state detecting area and extending in the longitudinal direction thereof; wherein the light emission axis of said auxiliary light emission means lies in said plane.

Claim 66

A focus state detecting apparatus compri­sing: focus state detecting means provided with an oblong focus state detecting area positioned on the object field and crossing the optical axis of said focus state detecting optical system, for effecting the focus state detection with the light beam from the object; and auxiliary light emission means for focus state detection, provided in a plane defined by said optical axis of said focus state detecting optical system and a line contained in said focus state detecting area and extending in the longitudinal direction thereof; wherein the light emission axis of said auxiliary light emission means lies in said plane.

Claim 67

An apparatus according to claim 52, wherein said focus state detecting means is adapted to effect the focus state detection with a light beam transmitted by a photographing optical system.

Claim 68

An apparatus according to claim 53, fur­ther comprising discrimination means for discriminating whether the object is of a now luminance, and, in case of a low luminance, activating said auxiliary light emission means.