Abstract: In the distance measuring apparatus, it is determined whether or not a pair of AF data obtained by a pair of employed sensors indicate a first predetermined necessary contrast, and a correlation value calculation is performed only when the contrast is detected. Then, it is determined whether or not the AF data in a pair of window ranges where the highest correlation is obtained in a correlation value calculation indicate a second predetermined necessary contrast. Only when it is determined that there is the contrast, the subsequent process such as a calculation of the distance from a distance measurement object is performed. Thus, an unnecessary correlation value calculation can be possibly omitted at a low contrast level. Furthermore, erroneous measurement of distance can be avoided.

Abstract: A rangefinder apparatus in accordance with the present invention forms an image of light from an object to be subjected to rangefinding onto a pair of line sensors each including a plurality of light-receiving elements, and generates AF data for computing a correlation value according to signals obtained from the light-receiving elements; acquires the AF data from a pair of employed sensor areas used for rangefinding in the pair of line sensors; determines a pair of window areas for selecting the AF data to be used for computing a correlation value within the pair of employed sensor areas, and successively computes correlation values while shifting the pair of window areas; detects a shift amount of the window areas yielding the highest correlation according to the correlation values computed by the correlation value computing means and calculates a distance to the object according to the shift amount yielding the highest correlation; and calculates an index value indicative of a degree of oscillation of the

Abstract: A rangefinder apparatus comprises AF data generating means; AF data acquiring means; interpolated correlation extreme value computing means for detecting at least one correlation extreme value from computed correlation values, and interpolating so as to compute the interpolated correlation extreme value(s); highest correlation value detecting means for detecting a highest correlation value exhibiting the highest correlation according to the interpolated correlation extreme value(s); shift amount computing means for computing the shift amount of a window area yielding the highest correlation value; rangefinding error determining means for determining the validity of thus computed shift amount depending on whether the shift amount computed by the shift amount computing means is outside of a predetermined range or not; and object distance calculating means for calculating the distance to an object according to the shift amount.

Abstract: This invention constitutes a measuring distance device including a sensor array which detects image signals of an object in a finder screen, a projection unit which projects a signal light on the object, a selection unit which selects a detection area for the image signal of the sensor array, a change unit (control unit) which makes detection areas selected by the selection unit different from each other when the signal light is projected or is not projected by the projection unit, and a focus adjustment unit which performs focus adjustment by an image signal output in the detection area of the sensor array selected by the selection unit. A reduction in time lag is achieved without increasing a read area, and an influence of harmful light is reduced. This device which can perform an accurate and high-speed process can be applied to a hybrid AF camera.

Abstract: A phase difference detection apparatus for detecting a phase difference between images formed on a pair of optical sensor arrays in which the calculation of a compensation value is simplified. When a compensation effectiveness judgment unit judges that compensation of the pair of image data rows would be effective, a left and right difference compensation unit calculates a compensation amount based on a difference in maximum values and minimum values in a pair of image data rows corresponding to the images produced by the optical sensor arrays and compensates the image data rows by the calculated compensation amount. Based upon the compensated values, a correlation calculation unit carries out a correlation calculation, and a maximum correlation detection unit detects a maximum correlation level. Based upon the maximum correlation level, a interpolation calculation unit carries out an interpolation calculation, and a phase difference is detected by a phase difference detection unit.

Abstract: A device for determining an amount of focus adjustment for an image-forming optical system which forms an image on a predetermined image plane includes a sensor, an image-re-forming optical system which re-forms the image on the sensor, and a reference member disposed at a position close to the predetermined image plane of the image-forming optical system. The projection image of the reference member is detected by the sensor, and a correction calculation is performed on the basis of the displacement of the projection image of the reference member from a preset position, so that errors in detection results caused by temperature variation, etc., are corrected.

Abstract: In the distance measuring apparatus, a passive AF sensor is used in which signals outputted from cells of a pair of line sensors are integrated for each cell to generate sensor data and an integration start signal is outputted upon start of integration, and when the peak value of the sensor data reaches an integration end value, an integration end signal is outputted. If the integration end signal is not outputted even after predetermined time elapses after integration is started in the AF sensor, the peak value of the sensor data is read to determine whether the integration is normally carried out. If the integration is not normally carried out, it is determined that distance measurement is impossible. If the integration is normally carried out, the sensor data is acquired from the AF sensor to carry out distance measurement thereby lessening the likelihood that it is determined that distance measurement is impossible more than necessary.

Abstract: Disclosed is a focus detecting device consisting mainly of a light receiving sensor, a reflecting mirror, a first detection circuit, and a focus detection circuit. The light receiving sensor has a plurality of photoelectric converters. The reflecting mirror is movable between a first position at which the reflecting mirror reflects light that comes from an objective, and routes the light to the light receiving sensor, and a second position at which the reflecting mirror recedes from the path of the light coming from the objective. The reflecting mirror has a member that helps form light distributions in a predetermined field on the light receiving sensor. Moreover, the reflecting mirror makes a return from the first position to the second position or vice versa. The first detection circuit detects a change in the light distributions formed in the predetermined field on the light receiving sensor which is observed between before and after the reflecting mirror makes a return.

Abstract: A focus detection device includes a plurality of light receiving sensors having sensitivity characteristics such that their respective visible spectra have different wavelength regions, a focus detection circuit which performs focus detection based on an output of any one of the light receiving sensors, and a determination circuit which determines whether or not the focus detection result is appropriate. If the determination circuit determines that the result is not appropriate, the focus detection circuit performs focus detection based on the output of another light receiving sensor.

Abstract: There are provided a rangefinder device which is capable of detecting that improper distance measurement through glass or the like has been performed, even when the glass is positioned at a certain or considerable distance from the camera, and a camera incorporating the rangefinder device. A projecting section projects a signal beam towards a photographic subject, and a light receiving section receives light from the photographic subject due to the projection via two different light paths. A distance information calculating circuit calculates distance information related to a distance to the photographic subject from the positional relationship between images received by the light receiving section. A position calculating circuit calculates first position information related to positions of the images received by the light receiving section based upon the calculated distance information.

Abstract: A distance measuring apparatus for a camera having a plurality of distance measurement zones, includes a light receiving device having a plurality of light sensors which output analog pixel signals corresponding to the amount of light received; an A/D converter which converts each analog pixel signal into digital pixel data; a logarithmic transformation device which performs logarithmic transformation on each digital pixel data at a predetermined logarithmic transformation range to obtain a first transformation data; a determination device which determines the contrast state of each distance measurement zone based on the first transformation data; a calculation device which calculates an average relative object brightness based on the first transformation data; and a control device which obtains a second transformation data by performing logarithmic transformation again by utilizing a predetermined object brightness range including the average relative object brightness in the distance measurement zone as a l

Abstract: In the distance measuring apparatus, it is determined whether or not a pair of AF data obtained by a pair of employed sensors indicate a first predetermined necessary contrast, and a correlation value calculation is performed only when the contrast is detected. Then, it is determined whether or not the AF data in a pair of window ranges where the highest correlation is obtained in a correlation value calculation indicate a second predetermined necessary contrast. Only when it is determined that there is the contrast, the subsequent process such as a calculation of the distance from a distance measurement object is performed. Thus, an unnecessary correlation value calculation can be possibly omitted at a low contrast level. Furthermore, erroneous measurement of distance can be avoided.

Abstract: In the distance measuring apparatus, a passive AF sensor is used in which signals outputted from cells of a pair of line sensors are integrated for each cell to generate sensor data and an integration start signal is outputted upon start of integration, and when the peak value of the sensor data reaches an integration end value, an integration end signal is outputted. If the integration end signal is not outputted even after predetermined time elapses after integration is started in the AF sensor, the peak value of the sensor data is read to determine whether the integration is normally carried out. If the integration is not normally carried out, it is determined that distance measurement is impossible. If the integration is normally carried out, the sensor data is acquired from the AF sensor to carry out distance measurement thereby lessening the likelihood that it is determined that distance measurement is impossible more than necessary.

Abstract: In an apparatus comprising a zoom lens and an electric flash, a range finder that determines, on the basis of an output result obtained by means of one method out of an active AF and a passive AF, whether or not to operate the other method, is utilized.

Abstract: The taking lens apparatus is capable of performing accurate focusing state determination by allowing optical adjustment of the focusing state determination optical system for the taking lens. The lens barrel of the taking lens apparatus comprises a focusing state determination lens barrel, which incorporates focusing state determination image-capturing elements, positions of which are adjustable by an operation ring.

Abstract: A rangefinder device and a camera are provided, which, in measuring a distance by the active method, are capable of properly measuring the distance even if the object to be measured is located at a short distance, while in measuring a distance by the passive method, are capable of measuring the distance without causing the conflict between far and near objects. A projecting section projects spot-shaped light on a range-finding object. A light receiving section comprises a plurality of photoelectric converting elements. A first calculating section calculates distance measurement information based on an output from the light receiving section receiving reflected light from the range-finding object, by driving the projecting section to project the light, and a second calculating section calculates distance measurement information based on an output from the light receiving section receiving extraneous light reflected from the range-finding object, without driving the projecting section.

Abstract: A distance measuring device includes a light emitting system that emits light toward an object that is subject to a distance measurement. A light receiving system is provided to receive optical images which are formed by an optical system. The light receiving system outputs data corresponding to the received images. The light receiving system is capable of receiving the object images when the light emitting system emits the light, and when the light emitting system does not emit the light. Further, the distance measuring device includes a control system that receives the data output by the light receiving system twice at the greatest, and performs distance measuring operations, which include a passive distance measurement and an active distance measurement, based on the data output by the light receiving system.

Abstract: There is disclosed a distance measuring equipment capable of performing efficiently a greater accuracy of focusing without troubling an operator, and a camera incorporating thereinto such a distance measuring equipment. By the use of the first focusing algorithm switches 61, 62 and 63 set up to the turn-off state, the turn-off state and the contact 62a side, respectively, so that AF-dedicated photo detector circuit 40 performs once a ratio arithmetic processing in accordance with photo-currents I1 and I2 from the PSD 30. In case of the short distance area, they are dealt with as the focusing data. In case of the middle distance area, the ratio arithmetic processing is performed by n times.

Abstract: The present invention discloses a camera system comprising: a first focus detection unit, which detects the focusing condition of an image-taking optical system; a second focus detection unit, which detects the focusing condition of the image-taking optical system at a higher precision than the first focus detection unit; and a control circuit, which controls a stepping motor for driving a focus lens. The control circuit performs closed loop control for driving the stepping motor based on the output of a rotation detector, which detects the rotation phase of the stepping motor, when controlling the stepping motor using the information based on the output of the first focus detection unit, and performs open control for driving the stepping motor a predetermined number of steps at a time, when controlling the stepping motor using the information based on the output of the second focus detection unit.

Abstract: Provided is a distance measuring apparatus that can cope with the problem of wrong distance measuring attributable to the presence of miscellaneous subjects and minimize the possibility of defocused photographing. In this distance measuring apparatus, passive-type distance measuring is carried out in accordance with a subject image signal for the central portion of a view field. Signal light for distance measuring from an infrared-emitting diode is projected on a subject in the central portion of the view field, and active-type distance measuring is carried out by means of a sensor array in accordance with reflected signal light reflected by the subject. According to the output result of the passive-type central distance measuring, a CPU determines whether or not to effect distance measuring for the peripheral portion of the view field based on an image signal for the peripheral portion.

Abstract: The present invention is a camera distance measuring device having an integral light receiving element for receiving light from a photographic object and outputting light received signals, and a fixed light elimination circuit for eliminating the fixed light component from the output signals of this integral light receiving element. This camera distance measuring device functions as an active distance measuring device by making the fixed light elimination circuit operative and functions as a passive distance measuring device by making the fixed light elimination circuit inoperative. When functioning as an active distance measuring device, this camera distance measuring device alternatively employs either a first illumination device such as a strobe light for illuminating a wide range including the photography range or a second illumination device such as an infrared LED for illuminating a spot-like range within the photography range.

Abstract: A multi-point autofocus system includes a focus detection device which can calculate a defocus amount for each of a plurality of focus detection zones in a picture plane; a selecting device for manually selecting a focus detection zone from the plurality of focus detection zones for which the defocus amount is to be calculated by the focus detection device; and a determining device for determining a valid focus detection zone by which a valid defocus amount can be calculated out of at least one of the plurality of focus detection zones other than the manually-selected focus detection zone, in such a manner that a higher priority is given to a focus detection zone than another focus detection zone of the plurality of focus detection zones in the case where the result of a calculation of the defocus amount of the manually-selected focus detection zone is invalid.

Abstract: This invention is a focusing apparatus including a pair of sensor arrays detecting object image signals obtained by a plurality of optical paths in multiple-point distance measurement, an arithmetic operation control section focusing on an object by comparison of relative positions of the object image, a light source consisting of a strobe section or a light projection section, and projecting focusing auxiliary light onto the dark object, and a determination section determining a part of a contrast equal to or greater than a preset, predetermined contrast to be a shadow based on the object image signals obtained when the auxiliary light is projected from the light source. The object image signals obtained from parts other than the part determined as the shadow are preferentially captured on each sensor array and used for focusing control.

Abstract: This invention constitutes a measuring distance device including a sensor array which detects image signals of an object in a finder screen, a projection unit which projects a signal light on the object, a selection unit which selects a detection area for the image signal of the sensor array, a change unit (control unit) which makes detection areas selected by the selection unit different from each other when the signal light is projected or is not projected by the projection unit, and a focus adjustment unit which performs focus adjustment by an image signal output in the detection area of the sensor array selected by the selection unit. A reduction in time lag is achieved without increasing a read area, and an influence of harmful light is reduced. This device which can perform an accurate and high-speed process can be applied to a hybrid AF camera.

Abstract: A focus detecting device includes a light receiving device which receives reflection light from an object of focus detection, an auxiliary light device which illuminates the object of focus detection with auxiliary light, and a control circuit which controls an illuminating action of the auxiliary light device and performs focus detection on the basis of a received-light signal output of the light receiving device. While the auxiliary light device is in process of being controlled to illuminate the object of focus detection, the control circuit compares the received-light signal output of the light receiving device with a prescribed value and causes the focus detection being made by controlling the auxiliary light device to stop if the received-light signal output is less than the prescribed value.

Abstract: In a distance measure system, an autofocus integrated circuit is furnished with a power source voltage and an integrating capacitor is preliminarily charged to a reference voltage VREF. A temperature sensor detects ambient temperature. Thereafter, under the control of a CPU, an infrared emitting diode emits pulsed infrared light and the integrating capacitor discharges by a voltage level corresponding to a distance to an object to be measured. On the occasion of integration by an integrating unit of a signal output from an arithmetic unit, discharging of the integrating capacitor is performed multiple times, corresponding to the ambient temperature measured by a temperature sensor.

Abstract: A panning shot check unit checks whether a panning shot is succeeded or not on the basis of an output from a focal point detection unit for detecting an in-focus state of a photographing lens to output a focal point detection signal and an output from a blurring detection unit for detecting an amount of blurring acting on the camera. A shutter speed change unit changes a shutter speed to obtain the effect of a panning shot when it is determined by the panning shot check unit that the panning shot is succeeded. A control unit turns on a panning shot success display unit in a finder when it is determined by the panning shot check unit that the panning shot is succeeded so as to inform a photographer that the panning shot is succeeded.

Abstract: There are provided a rangefinder device which is capable of detecting that improper distance measurement through glass or the like has been performed, even when the glass is positioned at a certain or considerable distance from the camera, and a camera incorporating the rangefinder device. A projecting section projects a signal beam towards a photographic subject, and a light receiving section receives light from the photographic subject due to the projection via two different light paths. A distance information calculating circuit calculates distance information related to a distance to the photographic subject from the positional relationship between images received by the light receiving section. A position calculating circuit calculates first position information related to positions of the images received by the light receiving section based upon the calculated distance information.

Abstract: Disclosed is a focus detecting device consisting mainly of a light receiving sensor, a reflecting mirror, a first detection circuit, and a focus detection circuit. The light receiving sensor has a plurality of photoelectric converters. The reflecting mirror is movable between a first position at which the reflecting mirror reflects light that comes from an objective, and routes the light to the light receiving sensor, and a second position at which the reflecting mirror recedes from the path of the light coming from the objective. The reflecting mirror has a member that helps form light distributions in a predetermined field on the light receiving sensor. Moreover, the reflecting mirror makes a return from the first position to the second position or vice versa. The first detection circuit detects a change in the light distributions formed in the predetermined field on the light receiving sensor which is observed between before and after the reflecting mirror makes a return.

Abstract: In an apparatus comprising a zoom lens and an electric flash, a range finder that determines, on the basis of an output result obtained by means of one method out of an active AF and a passive AF, whether or not to operate the other method, is utilized.

Abstract: Provided is a distance measuring apparatus that can cope with the problem of wrong distance measuring attributable to the presence of miscellaneous subjects and minimize the possibility of defocused photographing. In this distance measuring apparatus, passive-type distance measuring is carried out in accordance with a subject image signal for the central portion of a view field. Signal light for distance measuring from an infrared-emitting diode is projected on a subject in the central portion of the view field, and active-type distance measuring is carried out by means of a sensor array in accordance with reflected signal light reflected by the subject. According to the output result of the passive-type central distance measuring, a CPU determines whether or not to effect distance measuring for the peripheral portion of the view field based on an image signal for the peripheral portion.

Abstract: A distance measuring apparatus for a camera having a plurality of distance measurement zones, includes a light receiving device having a plurality of light sensors which output analog pixel signals corresponding to the amount of light received; an A/D converter which converts each analog pixel signal into digital pixel data; a logarithmic transformation device which performs logarithmic transformation on each digital pixel data at a predetermined logarithmic transformation range to obtain a first transformation data; a determination device which determines the contrast state of each distance measurement zone based on the first transformation data; a calculation device which calculates an average relative object brightness based on the first transformation data; and a control device which obtains a second transformation data by performing logarithmic transformation again by utilizing a predetermined object brightness range including the average relative object brightness in the distance measurement zone as a l

Abstract: A focus detecting device comprising a taking lens for photographing an object, a relay optical system for re-forming an object image via the taking lens, and a detecting means having first and second sensor pairs for detecting the image re-formed by the relay optical system, wherein focus detection is accomplished using one sensor of the first sensor pair and one sensor of the second sensor pair.

Abstract: For providing an accurate focus detection result or distance measurement result, a focus detection device, according to the present invention, comprises a plurality of light receiving sensors each of which has sensitivity characteristics different from each other, a focus detection circuit for performing focus detection based on an output of any one of the light receiving sensors and a determination circuit for determining whether or not the focus detection result is appropriate, wherein if the determination circuit determines that the result is not appropriate, the focus detection circuit performs focus detection based on the output of another light receiving sensor.

Abstract: A focus detecting device for performing focus detection of passive type using phase-difference detection includes a sensor composed of a plurality of pixels which are paired, and a judgment circuit for judging whether a target image for focus detection is a thin line close to a pixel pitch of the sensor, on the basis of a correlation varying amount of two images formed divisionally on the sensor and an output difference of adjacent pixels of each of the two images, so that it is possible to cope with the thin-line image.

Abstract: The present invention is a camera distance measuring device having an integral light receiving element for receiving light from a photographic object and outputting light received signals, and a fixed light elimination circuit for eliminating the fixed light component from the output signals of this integral light receiving element. This camera distance measuring device functions as an active distance measuring device by making the fixed light elimination circuit operative and functions as a passive distance measuring device by making the fixed light elimination circuit inoperative. When functioning as an active distance measuring device, this camera distance measuring device alternatively employs either a first illumination device such as a strobe light for illuminating a wide range including the photography range or a second illumination device such as an infrared LED for illuminating a spot-like range within the photography range.

Abstract: An automatic focus adjusting apparatus includes an image move-amount detecting section, an image position predicting section and a control section. The image move-amount detecting section detects, for each of a pair of images of a subject divided in a predetermined direction, image positions of the subject in an image-divided direction and in a direction approximately orthogonal with this image-divided direction respectively on photoelectric conversion elements at mutually different first and second times respectively, and obtains move amounts of the images of the subject in the image-divided direction based on a result of this detection. The image position predicting section predicts an image position of the subject in an image-divided direction at a third time different from the first and second times, based on an output from the image move-amount detecting section.

Abstract: There is provided a camera with an automatic focusing device having hybrid AF unit capable of always performing a reliable automatic focusing operation on a moving object to provide a more preferable photographic result. The camera includes first distance measuring unit 4 having at least a pair of light receiving sensors, for measuring the distance of an object by receiving a beam of light from the object, second distance measuring unit 3 having light projecting unit for projecting a beam of light upon the object and light receiving unit for receiving a beam of light reflected therefrom, for measuring the distance of the object by projecting a beam of light upon the object with the light projecting unit and by receiving a beam of light reflected therefrom with the light receiving unit and distance measuring method selecting unit 2 for selecting either the first distance measuring unit or the second distance measuring unit.

Abstract: The present invention relates to a zoom lens apparatus used with a television camera and provides an apparatus constructed in such structure that, on the occasion of limiting an angle of view, a zoom state set and manipulated by a photographer is converted to information about an angle of view, the angle of view is compared with a limit angle of view, and the angle of view is prevented from exceeding the limit angle of view.

Abstract: There is provided a distance measuring apparatus in a lens-shutter type camera provided with a photographic lens, a focal length of the photographic lens being variable.

Abstract: A focal point detection apparatus having a plurality of detection areas comprises a view field mask disposed in the vicinity of a prearranged imaging plane of a photographing lens and provided with a plurality of view field apertures, a condenser lens provided with a plurality of lens units for respectively condensing light fluxes transmitting the plurality of view field apertures, and a re-imaging optical system provided with a plurality of re-imaging lens units for dividing a light flux transmitting each view field aperture into a pair of light fluxes transmitting different areas of the exit pupil of the photographing lens and for forming images of the respective view field apertures on light receiving means.

Abstract: A camera with a distance measuring apparatus has distance measuring functions by means of an active system and a passive system to allow good distance measurement with respect to an object in a wide variety of conditions. The camera includes a first signal forming unit, a second signal forming unit, a release detecting unit, an object condition detecting unit and a selective control unit. The first signal forming unit projects light distance measurement light from a light projecting unit, receives a reflection signal of the distance measurement light from the object at a light receiving unit and forms a focusing signal for the object. The second signal forming unit monitors the luminance distribution state of the object using an image signal detecting unit and forms a focusing signal for the object. The release detecting unit detects whether or not a release operating member is operated.

Abstract: The present invention relates to a system for determining the alignment of an object, whose image is to be recorded, with a coupling eyepiece and an image capture apparatus that defines an image plane (Pi), comprising: an image capture apparatus (2) equipped with the ability for adjusting its own position; a light source (1) that emits at least two non-focused luminous dots (1a, 1b); eyepiece coupling lens(es) or element(s) (3) that focus on an object plane (Po); an opaque mask (4) that is perforated with at least two holes (5a, 5b) and that is positioned in front of light source (1) such that it transmits at least part of the light emitted by the light source; and calculating mechanism for determining whether alignment exists and, in the case of non-alignment, for quantifying the non-alignment.

Abstract: A focus detecting device capable of focus detection in a plurality of focus-detecting areas, includes a setter for setting a first group including at least two focus-detecting areas, and a second group including a plurality of focus-detecting areas, which are not included in the first group, and a focus detector means for executing focus detection in the order from the focus-detecting areas included in the first group. The focus detecter ends focus detection without executing focus detection in the focus-detecting areas included in the second group, when the focus-detecting area included in the first group satisfies a predetermined condition.

Abstract: When performing distance measuring operation in an active mode, a charging time is compared to a predetermined period, and if the charging time is shorter than the predetermined period, then it is determined that the object is at a short distance, whereas, if the charging time is longer than the predetermined period, then it is determined that the object is in the distance. Since the positions where images of an object are formed on sensors depend upon the distance to the object, in other words, the phase difference between the images of the object depends upon the distance to the object, when the object is in the distance, the correlation operation is performed in a shift range corresponding to the long distance, whereas, when the object is at a short distance, the correlation operation is omitted in a shift range corresponding to the long distance and the correlation operation is performed in a range corresponding to a short distance.

Abstract: There is provided a distance measuring apparatus in a lens-shutter type camera provided with a photographic lens, a focal length of the photographic lens being variable.

Abstract: An optical apparatus having a focus adjusting function, including: a focus detection unit for executing a focus detection operation for each of a plurality of focus areas set in an image plane; a grouping unit for grouping the image plane in accordance with a distribution of defocus amounts or distances obtained from focus detection results of the plurality of focus areas; a focus area selecting unit for selecting at least one focus area from the plurality of focus areas in accordance with a grouping result; a defocus amount comparing unit for comparing a defocus amount of the selected focus area selected with a predetermined defocus amount; a lens driving unit for driving a lens until the selected focus area is made in-focus, if a comparison result by the defocus amount comparing unit shows that the defocus amount of the selected focus area is smaller than the predetermined defocus amount; and a focus area re-selecting unit for re-selecting a focus area by driving the lens in accordance with the defocus amou

Abstract: A focus detector amplifies a plurality of sets of output signals from a plurality of photoelectric transfer element arrays by the most preferable amplifying mode and focuses a focus of an optical lens system on a desired object among a plurality of objects corresponding to the photoelectric transfer element arrays by selecting a method for deciding a defocus among a nearest position priority method, a lateral direction priority method and a reliability priority method responding to a condition of the objects.

Abstract: A multipoint autofocus system is provided with a judging apparatus and controller. The multipoint autofocus system detects a focus state of objects at different positions in a plurality of focus detection zones of an image surface. Thereafter, information on the detected focus state is selected, so that a focusing optical system is moved in accordance with the selected focus data. The judging apparatus judges the contrast of the detected object in the focus detection zones. The controller selects data representing the shortest focus from among the focus data of the objects in the focus detection zones in which the judged object contrast is higher than a predetermined value.

Abstract: A camera of this invention includes a photographing optical system, an imaging means, an optical path splitting means, a lens shutter, a focus detecting means, and a correcting means. The imaging means senses an optical image, formed by a light beam passing through the photographing optical system, on a predetermined photographing plane. The optical path splitting means splits at least a portion of a light beam passing through the photographing optical system. The lens shutter opens and closes the optical path of the photographing optical system. The focus detecting means receives the split light beam and detects the defocus amount of an image formation plane of the light beam with respect to a predetermined primary image formation plane. The correcting means corrects any deviation between an image formation plane of the photographing light beam imaged by the imaging means and the primary image formation plane.