Abstract: An image pickup apparatus includes an image sensor including a pair of focus detection pixels configured to receive light beams that have passed through different areas in an exit pupil of an imaging optical system, and at least one processor caused to function as a focus detection unit configured to detect focus of the imaging optical system by using a pair of focus detection signals which is generated by using output signals from the pair of focus detection pixels. The focus detection unit can detect the focus in a plurality of spatial frequency bands. The focus detection unit acquires a focus detection result to be used in a spatial frequency band corresponding to an aberration amount of the imaging optical system, the spatial frequency band being included in the plurality of spatial frequency bands.

Abstract: An image capturing apparatus capable of performing highly-accurate focus detection at a high frame rate with minimal time lag is provided with a focus position detection unit configured to calculate a focus position by using an image via an image capturing optical system, an aberration information acquisition unit configured to acquire aberration information of the image capturing optical system, a color information acquisition unit configured to acquire color information of a subject in a focus detection region, a first correction value calculation unit configured to calculate a first correction value for correcting the focus position based on the aberration information, a second correction value calculation unit configured to calculate a second correction value for correcting the focus position based on the first correction value and the color information, and a correction unit configured to correct the focus position by using the second correction value.

Abstract: A control apparatus is configured to control a driver configured to drive a driven member, which driver is provided in an optical apparatus that is attachable to and detachable from an image pickup apparatus. The control apparatus includes an information acquirer configured to acquire information on a suppliable power from the image pickup apparatus to the optical apparatus, and a changer configured to change a control method of the driver according to the information.

Abstract: An optical image tracker is disclosed. The optical image tracker includes a multi-dimensional translation stage. An optical image detector is disposed on a surface of the multi-dimensional translation stage. An objective lens is coupled to the optical image detector and configured to focus a collimated beam of light on the optical image detector, wherein the collimated beam of light includes a specific field of view within a field of regard, and the multi-dimensional translation stage is configured to position the optical image detector to detect the collimated beam of light.

Abstract: A medical navigation system is provided for acquiring a depth map of a surgical site of interest in a patient. The medical navigation system comprises a camera, a light projecting device, a display, and a controller. The controller has a processor coupled to a memory. The controller is configured to generate a signal provided to the light projecting device to project an edge indicator on the surgical site of interest, generate a signal to operate the camera to perform a focus sweep and capture a plurality of images during the focus sweep where the plurality of images includes the projected edge indicator, receive from the camera data representing the plurality of images captured during the focus sweep, and generate a depth map of the surgical site of interest using the data representing the plurality of images.

Abstract: Spatial resolution can be improved in multi-lens digital cameras. Each lens can have the same or similar field of view, but can be associated with different modulation transfer functions defining varying sharpness based on location within the field of view. The image information received from each lens can be combined to form an image based on the sharpness of the image information received from each lens.

Abstract: The camera side mount is brought, by relative rotation with the accessory side mount, from a first state where each accessory side bayonet claw is inserted between the camera side bayonet claws into a second state where the camera side and accessory side bayonet claws engage with each other. The leaf spring biasing the camera side contact pins in the protruding direction is disposed between the camera side mount and the camera body. When the camera being in the normal position is viewed from the direction facing the camera side mount, the leaf spring extends from both sides of the mount center line, which extends from the center of the camera side mount in the direction of gravity, toward the camera side contact pins. The camera side contact pins are arranged at positions other than a position on the mount center line.

Abstract: A navigation device 10 comprises: position detecting means 11 for determining the current position of a user from the absolute position in longitude and latitude by using the electric waves coming from a plurality of artificial satellites going around the earth; storage means 14 for storing the coordinates in longitude and latitude of nodes, as obtained by setting a starting point and a final place, on a scheduled route; display means 12 for displaying the current position and the scheduled route; and control means 16 for controlling the display on the display means 12 by converting the angular data of the absolute positions and the coordinates into distance data while making corrections according to the current position, and by calculating an element between the nodes thereby to calculate whether or not the current position is on the scheduled route, in dependence upon whether or not the distance between the element and the current position is within a predetermined range.

Abstract: A photographing system including a photographing device for capturing an image, and a lighting device that is capable of being mounted on the photographing device is provided. The lighting device includes a plurality of light sources configured as a solid state light-emitting device, and has a photographing auxiliary light function for allowing the solid state light-emitting device to be turned on to emit light during photographing and an autofocus (AF) auxiliary light function for allowing the solid state light-emitting device to be turned on to emit a predetermined amount of light when contrast AF is performed. And at least part of the light sources is shared when the photographing auxiliary light function and the AF auxiliary light function are performed.

Abstract: A method and system for reducing visual ghost artifacts in plano-stereoscopic image transmissions is provided. Such visual ghost artifacts are reduced by retrieving a non-linear image representation comprising left and right image representations using an image processor, where each of the left and right image representations have a plurality of color component sub-images. The non-linear left and right image representations are transformed into respective linear left and right image representations. A left or right image compensation signal is generated by applying the determined at least one ghosting coefficient to its associated one of the plurality of color component sub-images. A respective compensated right or left image is generated by subtracting the left or right image compensation signal from the uncompensated linear left or right image representation.

Abstract: An imaging apparatus includes: a lens-interchangeable type imaging apparatus body which includes a solid-state imaging device; and an interchangeable lens as defined herein; and the interchangeable lens is provided with a first storage portion which stores individual difference information about brightness of the interchangeable lens; and the lens-interchangeable type imaging apparatus body is provided with a second storage portion which stores information about a change of incident light sensitivity of the solid-state imaging device relative to each diaphragm value, and a control portion which uses the individual difference information about the brightness read from the first storage portion of the mounted interchangeable lens and the information about the change of the sensitivity in the second storage portion to thereby correct exposure at a time of imaging the photographic subject.

Abstract: An 3D camera module includes a first and a second imaging units, a storage unit, a color separation unit, a main processor unit, an image processing unit, a driving unit, an image combining unit and two OIS units. The first and second imaging units capture images of an object(s) from different angles. The color separation unit separates the images into red, green and blue colors. The main processor unit calculates MTF values of the images and determines a shooting mode of the 3D camera module. The image processing unit processes the images to compensate for blurring of the images caused by being out of focus. The driving unit drives the first and second imaging units to optimum focusing positions according to MTF values. The image combining unit combines the images into a 3D image. The OIS units respectively detect and compensate for shaking of the first and second imaging units.

Abstract: A 3D AF camera module includes first and second imaging units, a storage unit, a color separation unit, a main processor unit, an image processing unit, first and second driving units, and an image combining unit. The first and second imaging units each capture an image of a scene from different angles. The color separation unit separates the images into red, green and blue colors. The main processor unit calculates MTF values of the images and determines a shooting mode of the 3D AF camera module. The image processing unit processes the images according to the MTF values to compensate for blurring of the images caused by being out of focus. The first and second driving units drive the first and second imaging units to points of optimum focuses according to MTF values. The image combining unit combines the images into a single 3D image.

Abstract: An imaging apparatus to which an accessory is detachably attached, said accessory including an optical member, includes a signal generation unit configured to generate a vertical synchronizing signal and output the generated vertical synchronizing signal, an imaging unit configured to accumulate charges in synchronization with the vertical synchronizing signal and output an imaging signal, a control unit configured to generate a clock signal and control data communication with the accessory based on the clock signal, a first terminal for sending the clock signal to the accessory, and a second terminal for communicating data with the accessory, in which the control unit, after the data communication via the second terminal, notifies timing at which the vertical synchronizing signal is output using the clock signal via the first terminal by changing a signal level of the first terminal after a lapse of a predetermined time while the signal level is kept at a predetermined level, and controls the accessory to dr

Abstract: An image-pickup apparatus to which a lens unit that includes an image-pickup optical system including a focus lens is attachable includes an image sensor configured to photoelectrically convert an object image formed via the lens unit that has been attached, and to generate an image signal, and a controller configured to generate information on driving of the focus lens in the lens unit based upon the image signal and to provide focus control, the controller communicating data with the lens unit, wherein the controller transmits information on a driving target position of the focus lens to the lens unit in a first control, and transmits information on a driving direction and driving speed of the focus lens to the lens unit in a second control different from the first control.

Abstract: A lens apparatus detachable from an image pickup apparatus includes a focus lens, a driver configured to drive the focus lens, a first position detector configured to detect a position of the focus lens, and a controller configured to correct the position of the focus lens detected by the first position detector to a position of the focus lens in a predetermined optical characteristic, to transmit a corrected position of the focus lens to the image pickup apparatus, to correct driving information of the focus lens in the predetermined characteristic received from the image pickup apparatus to driving information of the focus lens in a current optical characteristic, and to instruct the driver to drive the focus lens in accordance with the position of the focus lens detected by the first position detector and corrected driving information of the focus lens.

Abstract: An auto-focusing apparatus controls backlash compensation driving of a focus lens during exposure preparation when focusing is performed by moving the focus lens to a target position of the focus lens. A shutter release time lag can be reduced, and in particular, the auto-focusing apparatus can be usefully applied to the case where a moving subject is photographed.

Abstract: An auto-focusing camera module includes a lens module, an image sensor, a color separation unit, a controller, and a shape memory alloy. The lens module captures light signal of an object. The image sensor senses the light and forms an image. The color separation unit separates the image into red image, green image and blue image. The controller calculates MTF values of the image and determines a shooting distance between the lens module and the object. When the shooting distance is greater than a predetermined distance value, the controller processes the image according to the MTF values to compensate blurs of the image caused by out of focus; when the shooting distance is equal to or less than the predetermined distance value, the controller controls the shape memory alloy drive the lens module to an optimum focusing position for focus according to the MTF values.

Abstract: An image taking system including: (a) a CMOS or CCD image sensor; (b) an interest-region setter configured to set regions of interest within an image taking area of the image sensor; (c) an acquiring-condition determiner configured to determine an image-data acquiring condition required for acquiring at least two image data generated in at least two of the regions of interest; and (d) an image-data acquirer configured to acquire the at least two image data. The acquiring-condition determiner includes an exposure-time determining portion configured to determine, as the image-data acquiring conditions, at least two different exposure times required for acquiring the at least two image data generated in the at least two regions of interest. The image-data acquirer includes an exposure-time-based-image-data acquiring portion configured to acquire the at least two image data, such that the acquired at least two image data are based on the at least two different exposure times.

Abstract: In an autofocus system, a focus measurement unit receives an image, and accordingly generates an associated focus value. A focus transform unit receives and then transforms the focus value provided by the focus measurement unit, therefore generating an associated transformed focus value. An in-focus position estimation unit obtains an in-focus position, in an analytical manner, according to some transformed focus values and some associated lens positions.

Abstract: A camera system (1) includes an interchangeable lens (200) and a camera body (100). The camera body (100) includes a body controller (140) configured to generate a command, and a sending unit (150) configured to send the generated command to the interchangeable lens. The interchangeable lens (200) includes a movable member (230, 260), a driving unit (233, 261) configured to drive the movable member, a receiving unit (250) configured to receive a command from the camera body, and a lens controller (240) configured to control the driving unit according to the received command. Further, a prediction unit (140, 240) is provided in either one of the camera body and the interchangeable lens, which predicts whether an operation of the driving unit of the interchangeable lens according to the received command will be completed within a predetermined time.

Abstract: An imaging apparatus that adjusts focus based on frequency components extracted from an image signal is provided. The apparatus includes a 1st order Infinite Impulse Response (IIR)-filter including a plurality of sample delayers having a plurality of line buffers for buffering and delaying a plurality of samples to sequentially read pixels of the image signal through raster scanning and extracting frequency components of the image signal from the read pixels by using the plurality of sample delayers; and a delay sample number controller for controlling the IIR-filter to match the number of horizontal pixels sequentially read from the image signal through raster scanning to the number of the plurality of samples buffered by the plurality of line buffers.

Abstract: An interchangeable lens includes a focus lens for changing a focus state of an object image, a driving unit for driving the focus lens, a lens controller for controlling the driving unit so as to move the focus lens forward and backward along the optical axis at a predetermined drive frequency, and a storage unit for storing therein drive frequency information representing a drive frequency at which the driving unit can control. A camera body obtains the drive frequency information from the interchangeable lens and performs control while referring to the drive frequency information.

Abstract: A lens-interchangeable camera includes a focus detector performing focus detection and a controller performing a drive control of a lens based on a defocus amount. The controller finishes focusing operation without driving the lens when the defocus amount is out a range of a first in-focus determination width, and performs the focusing operation when the defocus amount is out a range of the first in-focus determination width. The controller finishes the focusing operation without performing the focus detection again after completing the drive when the defocus amount is out a range of a second in-focus determination width, and performs the focus detection again after completing the drive when the defocus amount is out a range of the second in-focus determination width. The second in-focus determination width is set to be greater than the first in-focus determination width and be greater than or equal to a drive limit value.

Abstract: An interchangeable lens includes a focus lens for changing a focus state of an object image, a driving unit for driving the focus lens, a lens controller for controlling the driving unit so as to move the focus lens forward and backward along the optical axis at a predetermined drive frequency, and a storage unit for storing therein drive frequency information representing a drive frequency at which the driving unit can control. A camera body obtains the drive frequency information from the interchangeable lens and performs control while referring to the drive frequency information.

Abstract: An auto focus (AF) apparatus and method for a camera that improves the AF action by reducing the number of time and steps required of a conventional apparatus and method. An encoder initial value is detected by measuring an initial position of a lens unit by means of an encoder; matching the measured encoder initial value to an initial position value to which the lens unit is to move while performing the auto focus; performing the auto focus starting from the matched initial position value, and dividing a distance that the lens unit is to cover into sections corresponding to a preset number of steps; detecting an edge value which shows a brightness change for a contour of a subject for as many as the number of the preset steps. The AF is completed by moving the lens unit to a position corresponding to a maximum edge value selected from among the detected edge values.

Abstract: Disclosed is an apparatus and method for auto-focusing a camera, which includes the steps of detecting an initial value of an encoder by measuring an initial position of a lens system, matching the measured initial value of the encoder with the initial position value of the lens system to be moved, measuring a distance value of a subject through a distance measuring sensor, determining a displacement that a focus lens has to be moved with respect to the measured distance value, and adjusting a position of the focus lens such that a position value of the focus lens actually moved is the same as the displacement value.

Abstract: Disclosed are a focus detecting apparatus capable detection in various light illumination conditions and an image acquiring apparatus having the same. The focus detecting apparatus may include a mark disposed on a primary image plane. A pair of images of the mark is detected by a sensor, the distance between which images is used to determine the main wavelength of the light received from a subject. The main wavelength is used in determining the chromatic aberration correction by which the defocus amount may be adjusted.

Abstract: A mobile terminal and auto-focusing method for the same are disclosed. The auto-focusing method uses a lens position error compensation and includes: detecting a target object during a photograph mode; determining a lens position at which a focus value gradient related to the detected target object changes sign while moving a lens of the camera module in units of one step size; and performing lens position compensation by moving the lens to the found lens position. As a result, the lens position errors caused by a conventional a voice coil motor are compensated, thereby providing rapid and fine auto-focusing.

Abstract: A method comprises receiving a focusing image and shifting the focusing image to obtain a shifted focusing image. In the method, a focus metric of the focusing image is calculated from the focusing image and the shifted focusing image, where the focus metric is configured for use as a factor in making an automatic focus adjustment determination. An automatic focusing apparatus includes a controller configured to implement the method.

Abstract: A control apparatus for controlling a driver driving an optical element of an image pickup device to adjust a focus position of the image pickup device in the capturing of an image of a subject, includes a relative angle variation calculating unit for calculating a relative angle variation, a mode change detecting unit for detecting of a change of a mode of the relative angle variation through determining whether the mode of the relative angle variation, calculated by the relative angle variation calculating unit, is a stable mode involving a small amount of change or an unstable mode involving a large amount of change, and a focus position control process startup unit for managing a startup of a focus position control process controlling the focus position through controlling the driver in response to a pattern of the change of the mode detected by the mode change detecting unit.

Abstract: In a camera having a focusing device, the direction of moving a focus lens included in a photographing lens is varied depending on the defocus state with reference to a specific position (e.g., reverse point) of the focus lens. For example, a camera having a defocus-amount detection part for detecting the defocus amount of the photographing lens, a focus-lens position detecting part for detecting the position of the focus lens, and a memory element for storing a specific position of the focus lens, comprises a focus-lens moving mechanism for moving the focus lens by inverting the correspondence between the defocus direction output from the defocus-amount detection part and the focus-lens moving direction according to the output of the focus-lens position detecting part and the output of the memory element.

Abstract: This invention provides a technique of stably focusing on a major object without any sense of discomfort regardless of differences in lens unit type in a camera body on which a lens unit can be detachably mounted. For this purpose, the type of lens unit connected to the camera is determined. Cutoff frequencies are then set for a low-pass filter and high-pass filter on the basis of the determination result. With regard to frequency component data in predetermined area of an image sensor, a peak hold circuit, integrator, and difference peak hold circuit each generate evaluate value information. A camera microcomputer transmits the obtained evaluate value information to a lens microcomputer in the lens unit.

Abstract: A control apparatus for controlling a driver driving an optical element of an image pickup device to adjust a focus position of the image pickup device in the capturing of an image of a subject, includes a focus position control process startup unit for managing a startup of a focus position control process, a focus position control process executing unit for executing the focus position control process that is started under the control of the focus position control process startup unit, and a startup condition adjusting unit for adjusting a startup condition of the focus position control process, based on a change in a saturated luminance count contained in the image captured in the focus position control process.

Abstract: An image pickup apparatus, in which a light is projected toward a physical object by projection means, and based on the reflected light by the physical object of the light, a defocus amount is detected (steps S2003 to S2008) by the first focus detection means and the second focus detection means, respectively, and a correction value for matching the defocus amount detected by the first focus detection means with the defocus amount detected by the second focus detection means is calculated and kept stored (step S2009), and at the photographing time, based on the defocus amount detected by the first focus detection means and the correction value kept stored, a focus adjustment lens within a photographic lens is driven, thereby preventing an inappropriate correction of the defocus amount.

Abstract: An image sensing apparatus includes an image sensing element to form an object image which enters via a photographing optical system, a distance measuring unit to measure distances to at least first and second points within a photographing frame using an optical path different from the optical system. A determination unit determines a relationship between a distance measuring result and a drive amount of the optical system, on the basis of the distance measuring result upon measuring a distance to the first point by the distance measuring unit and a change in contrast of the object image formed at a position corresponding to the first point on the image sensing element when a focal point position of the optical system has changed. A control unit controls the focal point position of the optical system, on the basis of a distance measuring result at the second point and the relationship.

Abstract: A CPU calculates integrating values of image-capturing signals in a band 1 obtained by removing through a band pass filter a low frequency component of image-capturing signal output from an image-capturing device and integrating values of the image-capturing signals in a band 3 retaining the low frequency component intact, each calculated in correspondence to one of a plurality of lens positions. The CPU then obtains focal point evaluation values based upon these integrating values in correspondence to the individual bands. In addition, when it is judged that the image-capturing signals are saturated, the CPU calculates a new evaluation value parameter 1 history record=(focal point evaluation value history record in band 3?focal point evaluation value history record in band 1). The CPU then determines a new evaluation value parameter 1 history record extremal value through a 3-point interpolation operation and calculates a lens position corresponding to the extremal value.

Abstract: An optical apparatus is disclosed which can control a position of a driven member with precision using a simple control algorithm. The optical apparatus includes an actuator, a driven member, a transmission mechanism for transmitting a driving force from the actuator to the driven member, a first detector for detecting driving of the actuator and for outputting a signal corresponding to a detection result, a second detector for detecting driving of the driven member and for outputting a signal corresponding to a detection result, and a controller for controlling the actuator, wherein the controller determines, after activating the actuator, one of the first and second detectors which the one outputs a signal corresponding to a predetermined driving amount earlier, and controls the actuator based on the signal from the one that has been determined.

Abstract: An auto-focusing device and an electronic image pickup apparatus facilitates realizing a high focusing accuracy and a quick focusing operation simultaneously using an inexpensive plastic lens mount. The auto-focusing device according includes a means for correcting the conversion reference, if necessary, for converting the object distance measured by the open-control range finding means to a focusing position of the focusing lens based on the conversion reference and for moving the focusing lens to the converted focusing position. The electronic image pickup apparatus includes the auto-focusing device.

Abstract: An electronic still camera includes a finder optical system for viewing a subject image. An imaging section obtains the subject image. A display section displays the subject image based on image data associated with the subject image obtained by the imaging section. A mode selecting section selects either a first mode in which the electronic still camera performs imaging operation using the imaging section while a user views the subject image through the finder optical system or a second mode in which the electronic still camera performs imaging operation using the imaging section while the user views the subject image on the display section. A first focus detection circuit performs a first focus detecting operation when the first mode is selected by the mode selecting section. A second focus detection circuit performs a second focus detecting operation when the second mode is selected by the mode selecting section.

Abstract: A lens control apparatus for controlling the position of a focusing lens includes a rotary operation member, a detector, having a rotary encoder coupled with the rotary operation member, which detects the amount of rotation per unit time of the rotary operation member by counting the number of pulses per unit time outputted from the rotary encoder, and a conversion circuit for converting a detection output of the detector into a signal indicative of the position of the focusing lens. Further, the lens control apparatus is provided with a control characteristic changing circuit for changing a control characteristic of the lens.

Abstract: In a lens-interchangeable digital single-lens reflex camera having a focus detection device, an autofocus device corrects a focus detection result by storing, on the camera side, the detection result obtained by a focus detection means and the deviation of the best imaging position of an image formed on an image taking element due to a low-pass filter inserted in front of the image taking element.

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.

Abstract: A focus detecting device of the kind using an area sensor which has a plurality of focus detecting areas necessitates setting a correction value for every one of the focus detecting areas and storing all the correction values thus obtained, whereas, according to the invention, the correction value for each of the focus detecting areas of the area sensor is obtained by an arithmetic operation using, as variables, two parameters indicative of the position of the area, so that a focus detecting device can be arranged to obviate the necessity of storing all the correction values for the respective focus detecting areas.

Abstract: An optical system has a focal point detection device which is suitable for telephotography and is applicable to lenses having different image screen sizes. The optical system includes a photograph section which forms an image of an object, a driving device which moves either the entire photograph section or a part thereof in an optical axis direction, a plurality of re-imaging optical systems which forms re-images of the image of the object by light beams passing through different portions of a pupil of the photograph section, a plurality of imaging devices disposed in the vicinity of image planes of the re-imaging optical systems, and a controller which controls the driving device based on electric signals from the imaging devices so that the image of the object is formed on a mechanical image plane of the photograph section.

Abstract: A focus setting system for a camera in which a photographer can observe a focused subject image in a viewfinder and which corrects the focus prior to exposure such that a photographed picture is in focus. Specifically, the focusing system corrects for errors introduced by varying apertures. The focusing system has a photographic lens which has a memory for storing focus error data which represents focusing adjustment values from an open aperture to a number of predetermined apertures. A focus detection device detects a focused state of the photographic lens using a portion of the incident light rays of the photographic lens. A first drive unit drives the photographic lens by calculating a focus drive amount which achieves focus at open aperture. The focus drive amount is calculated from the focus error data and the focus state detected by the focus detection device.

Abstract: A calculation circuit compares a current focus evaluation value provided from a focus evaluation value generation circuit, with a focus evaluation value, of one preceding field stored in a memory, to determine whether a CCD is in-focus or not. The calculation circuit provides a driving signal VD to a linear motor so that the CCD moves toward the in-focus position. A position prediction circuit predicts the position where the CCD arrives after a predetermined time period according to the driving signal VD. A comparator circuit compares a predicted result from the position prediction circuit with the actual moved position of the CCD detected by a position detection circuit to provide a signal Dpr corresponding to an amount of load according to the comparison result. A correction value determination circuit and a bias determination circuit correct the level of driving signal VD in response to signal Dpr to supply a second corrected driving signal VD2 to a voice coil.

Abstract: An automatic focus device capable of optimum focus lens driving control corresponding to the magnitude of the positional error of the focus lens. The automatic focus device specifies the target position of the focus lens based on information relating to the defocus distance of the focus lens, the velocity of the subject image, the current position of the focus lens and controls the driving power of the focus lens based on non-linear functions of the positional error defined as the difference between the target position and the current position of the focus lens.

Abstract: A device has a photometry unit for performing a photometry operation of an object field using an accumulation type photometry element, and an accumulation time determination unit for determining the accumulation time of the photometry element. The accumulation time determination unit determines the value of the accumulation time for the next photometry operation by calculating a weighted average of the accumulation times in previous photometry operations. Since the value of the accumulation time for the next photometry operation is determined by calculating a weighted average of the accumulation times in previous photometry operations, the influence of flickering of an illumination light source can be eliminated, and a photometered value can be output within a short period of time.

Abstract: An interchangeable lens camera including an interchangeable lens having a photographic optical system, a lens mount to mount the interchangeable lens, a lens side communication terminal to communicate, a storage circuit to store lens data representing an optical property of the photographic optical system of the interchangeable lens, and a lens side communication device to transmit the lens data stored in the storage circuit through the lens side communication terminal, and a camera body having a body mount engageable with the lens mount to mount the interchangeable lens on the camera body, a sensor to receive light from a field through the photographic optical system and to generate an output corresponding to the light received, a processing circuit to process the output generated from the sensor and to output a condition signal, based on the processed output, indicating a condition of a subject image formed by the photographic optical system, a body side communication terminal connected to the lens side com