Abstract: An imaging apparatus includes an imaging unit configured to photoelectrically convert light of an object image formed by an imaging optical system to generate a signal, a first detection unit configured to detect a focusing state of the imaging optical system based on the signal generated by the imaging unit, a sensor configured to generate a signal different from the signal generated by the imaging unit without using the imaging optical system, and a second detection unit configured to detect an in-focus position of the imaging optical system based on the signal generated by the sensor. The sensor is located such that an amount of overlap between a detection range of the first detection unit and a detection range of the second detection unit at a first object distance is equal to an amount of overlap between those at a second object distance that is close to an infinite distance side compared to the first object distance.

Abstract: A portable telephone 10 comprises: focus state judging means 30 for judging whether or not an image captured from a camera 12 is in a focus state; focus state display means 31 for indicating both the focus state and a focus direction with the LED 13 and/or through the speaker 14; focus state storage means 32 for storing the temporal progress of the focus states of images obtained by the focus state judging means 30 with the temporal progress of the captured images; focus direction judging means 33 for judging a focus direction from the temporal progress of the focus states obtained by the focus state storage means 32; display sections 15 and 16 for displaying character information, image information, and the focus state; an LED 13 for displaying the focus state by emitting light; and a speaker 14 for informing about the focus state with voice or sound.

Abstract: A digital camera includes: an evaluation value calculation unit that calculates a focal point evaluation value that changes in correspondence to a position assumed by a focus lens based upon image signals; a focal adjustment unit that executes an AF search by detecting a focus match position based upon resulting focal point evaluation values and driving the focus lens to the focus match position; a face recognition unit that recognizes a face of a person in an image by analyzing the image signals; a distance calculation unit that determines an approximate distance to the face based upon the recognized face size; and a lens position determining unit that determines a focus lens position to be set as a start point of the AF search by the focal adjustment unit based upon the approximate distance to the face having been determined by the distance calculation unit.

Abstract: The autofocus adjustment device comprises a distance-measuring sensor and a contrast system AF, and is capable of attaining further speeding up and high accuracy. The autofocus adjustment device drives a focus lens according to the measurement result of a distance-measuring sensor and then performs focus adjustment according to a contrast system according to the image signal outputted from a solid-state image pickup element, and makes variable the search range and determination area of the contrast AF according to the measured distance from the object, brightness of the object, focal length and aperture, etc. of the lens. The distance-measuring sensor measures the distance from the object periodically before a release button is depressed and speeds up the focusing when the release button is depressed.

Abstract: An auto focus unit, comprising a pursuit block, a scanning area setting block, a change area setting block, a permission block, and a lens driver, is provided. The pursuit block pursues the movements of a target object. The scanning area setting block designates a part of an object-area as a scanning area at first timing. After first timing, the scanning area setting block is able to reset the scanning area to the now location where the targeted object has moved. The change area setting block defines an area of a predetermined range as a change area at the first timing. The permission block orders the scanning area setting block to reset the scanning area when the location where the targeted object moved is outside of the change area. The lens driver orders a focus lens to move so that an optical image of the scanning area is focused on.

Abstract: A focus control apparatus includes a signal generator for generating a first signal in accordance with a predetermined frequency component of an image signal obtained by photoelectrically converting an image of a subject formed by an image-taking optical system, a detector for detecting a second signal different from the first signal, and a controller for detecting a movement of the subject based on the second signal and for switching driving of the image-taking optical system based on the detection, wherein the controller controls driving of the image-taking optical system based on the first signal.

Abstract: A lens apparatus includes an optical lens unit including a movable lens portion, a drive unit configured to drive the movable lens portion, a control unit configured to control the drive unit, a difference calculation unit configured to calculate a difference between command signals received at intervals of a predetermined period, and an addition unit configured to add the difference calculated by the difference calculation unit to each of the command signals, wherein the control unit controls the drive unit based on a result of an addition performed by the addition unit.

Abstract: An electronic camera includes a shutter button. When the shutter button is half-depressed, a focal level of an object is determined on the basis of an image signal outputted from an imaging device, and a moving start position of a focus lens is settled on the basis of the determination result. More specifically, a correction amount of the moving start position is settled in accordance with the determination result of the focal level, and a position that subtracts the correction amount from a lens position at a time the shutter button being half-depressed is settled as the moving start position. The higher the focal level, the more reduced the correction amount. The focus lens gradually moves toward the imaging device from the settled moving start position, and a focal position is specified on the basis of the image signal outputted from the imaging device at each step.

Abstract: An automatic focusing method for a camera, including scanning in a macro mode, scanning in a normal mode, and additional scanning. In the scanning in the macro mode, a region within a first distance is scanned if the macro mode is set by a user. In the scanning in the normal mode, a region beyond the first distance is scanned if the normal mode is set by the user. In the additional scanning, the scanning in the normal mode is performed additionally if it is determined that the position of the focus lens found in the scanning in the macro mode does not have the largest focus value, and the scanning in the macro mode is performed additionally if it is determined that the position of the focus lens found in the scanning in the normal mode does not have the largest focus value.

Abstract: A lens-controlling device controls a first lens unit which moves for zooming and a second lens unit which moves for correcting the displacement of an image plane caused by zooming and for focusing. The lens-controlling device includes a memory which stores data for obtaining target-position information representing a target position to which the second lens unit is to be moved, the target position corresponding to a position to which the first lens unit is moved from a current position and a controller which generates the target-position information on the basis of the data and controls the movement of the second lens unit on the basis of position information of the first lens unit and the target-position information.

Abstract: An imaging device is provided. The imaging device can maintain a constant angle of view even if a focal distance of an entire lens system changes as a focusing lens moves. The imaging device includes an image sensor, a focusing lens, a lens driver, an image generator, a magnification changing rate obtaining unit, and a size changer. The image sensor shoots a snap shot of an object, and the focusing lens performs focusing on the object. The lens driver drives the focusing lens to a plurality of focal points for the object, and the image generator generates an image on the basis of a photograph signal from the image sensor. The magnification changing rate obtaining unit obtains a magnification changing rate for each focal point such that an angle of view for each image photographed at each focal point of the focusing lens is maintained constant. The size changer changes the size of the image on the basis of the magnification changing rate.

Abstract: A auto focusing method for face detection of a digital imaging device is described, in which high-frequency information of a focusing area is increased according to a size, a position of a face of a person to be shot, and an image area at least covering the face and body of the person, thereby improving a focusing success ratio.

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: An optical apparatus is disclosed which achieves high focusing accuracy and favorable responsiveness in AF control. The apparatus includes a signal generator which extracts signals in a plurality of frequency bands from an output from an image-pickup part and generates focus signals from the extracted signals, and a controller which performs focus control such that the focus signal approaches the highest value. The controller uses a first focus signal and a second focus signal in the focus control. The second focus signal is a synthesis signal formed by synthesizing a focus signal in a relatively high or the highest frequency band of the plurality of frequency bands and a focus signal in another frequency band and contains a component of the focus signal in the relatively high or highest frequency band at a higher ratio as compared with the first focus signal.

Abstract: The embodiments of the invention relate to automatic focusing methods and apparatus suitable for use in digital imaging devices. The proposed methods and apparatus evaluate the focus condition of the optical system by evaluating the digitized image, without requiring additional hardware besides the digital image-capture signal flow path. A method for computing the appropriate direction and magnitude of optical system adjustment, based on the evaluated focus condition, is provided. The computed quantities are communicated to the lens driving apparatus to reposition and adjust the optical system and to incrementally obtain a better focus. Upon reaching a desired focus quality, the device is prevented from controlling the lens driving apparatus.

Abstract: In an automatic focusing device generating a luminance signal by scanning a picked-up digital image signal, evaluating the contrast of the luminance signal, and driving its focusing based on the evaluation; the scanning includes at least a part where scan is performed in a zigzag-like manner. With this configuration, focusing is facilitated for an object having no high frequency components in the horizontal direction. This invention can be understood as an invention of a method.

Abstract: In the auto focus system, focus evaluation values indicating a degree of sharpness of images are sought from a plurality of image pickup devices placed at positions of different light path lengths, a travel distance converging to zero as a focus of a picture-taking lens approaches a focusing position is sought by using a difference or a ratio between the two focus evaluation values, and the focus is moved to a new moving target position which is a value of a current moving target position having the travel distance added thereto so as to securely move the focus to the focusing position by stable operation of the focus suited to characteristics of the focus evaluation values.

Abstract: A method for automatic focus for an image capture device comprising a lens, the method comprising, for a first lens position, processing image data generated at a plurality of local focus positions of the lens in order to generate first metric data representing a focus measure for the first lens position, adjusting the lens position on the basis of the first metric data, and generating corresponding second metric data for at least one local focus position at the new lens position, and determining an estimated point of true focus for the lens on the basis of the first and second metric data.

Abstract: The present invention relates to autofocusing apparatus of a camera. The autofocusing apparatus of a camera includes a lens section on which a light signal is incident; an image sensor and ISP section that receives the light signal incident on the lens section so as to convert into an electrical signal and then outputs digitalized image data; an autofocus DSP that receives the image data from the image sensor and ISP section so as to extract predetermined image components, divides the central region of a picture into N regions (N is an integer larger than two), calculates a focus value for each region by integrating the predetermined image components, and calculates the maximum value while moving the focus lens of the lens section in the up and down direction in accordance with the focus value calculated for each region; and a driving section that drives the focus lens of the lens section.

Abstract: An image pickup apparatus includes a multifocal optical system having at least two different focal lengths; an image pickup device for converting an optical image formed by the multifocal optical system into an image signal; a first image processor for forming an original image defined by an object image at each focal length of the multifocal optical system with the image signal received from the image pickup device; and a second image processor for trimming the original image formed by the first image processor. An object image of an angle-of-view corresponding to an intermediate focal length between the two focal lengths of the multifocal optical system is complemented by a trimmed image formed by the second image processor.

Abstract: A focus detection apparatus includes a lens drive mechanism for moving a focusing lens group, and a controller for detecting a contrast value of the object image and moving the focusing lens group. The controller calculates a difference between maximum and minimum contrast values detected at the different positions of the focusing lens group; compares contrast values at two adjacent lens positions to determine whether the contrast value increases successively and subsequently decreases successively; detects a maximum contrast value, if the contrast value increases successively and subsequently decreases successively; calculates the maximum contrast value via a point of intersection between straight lines of two linear approximation expressions if the difference is equal to or greater than a predetermined value; calculates the maximum contrast value from a quadratic approximation expression, if the difference is smaller than the predetermined value.

Abstract: An apparatus configured to optimize autofocus performance in photographing a still picture includes a focus adjusting device configured to detect a position of a focus lens in accordance with movement of the focus lens, a designating device which designates still picture photography, a control device which causes the focus adjusting device to operate in one of a first mode in which said focus adjusting device maintains a current in-focus position when the designating device is operated, and a second mode in which said focus adjusting device adjusts the position of the focus lens to obtain an in-focus position when said designating device is operated.

Abstract: A focusing apparatus includes a first sensor and a second sensor configured to receive an optical image of a target workpiece to be inspected and convert it photoelectrically, a first optical system configured to make the optical image be focused on the first sensor, a second optical system configured to branch the optical image from the first optical system and to make a branched optical image be focused on the second sensor, a focus detection part configured to input a first image signal photoelectrically converted by the first sensor and a second image signal photoelectrically converted by the second sensor and to detect a focus position of the optical image by using high frequency components of the first image signal and the second image signal, and a focus control part configured to control a focus of the first optical system based on the focus position detected by the focus detection part.

Abstract: A CPU calculates integrating values of image-capturing signals in band 1 obtained by removing a frequency component equal to or lower than a first cutoff frequency from an image-capturing signal output from an image-capturing element through a band pass filter and integrating values of an image-capturing signal in band 2 obtained by removing a frequency component equal to or lower than a second cutoff frequency through a band pass filter, each in correspondence to one of a plurality of lens positions. The CPU then calculates focal point evaluation values by using these integrating values in correspondence to the individual bands. In addition, when the largest evaluation value in band 1 is judged to correspond to the closeup end position of the lens, the CPU makes a decision as to whether or not a focus match is achieved at the closeup end.

Abstract: A focus detection apparatus includes a focusing lens group, and a controller. The controller establishes a first predetermined number and a first criterial value if a maximum contrast value and/or minimum contrast value is outside a predetermined range, and a second predetermined number and second criterial value if the maximum and minimum contrast values are within the predetermined range; compares contrast values detected at adjacent positions to determine whether the contrast value of the object image increases once and subsequently decreases by the first or second predetermined number of times; detects a maximum contrast value if the contrast value of the object image increases once and subsequently decreases by the first or second predetermined number of times; determines a difference between the maximum contrast value and a detected contrast value; and selects the maximum contrast value if the difference exceeds the first/second criterial value.

Abstract: Auto focus methods for electronic cameras are disclosed. The method of the present invention obtains and compares evaluation values (high frequency component (HFC)) corresponding to desired image signals from left or right locations relative to a center of a zoom lens of an electronic camera, thereby locating the maximal evaluation value. The location corresponding to the located maximal evaluation value is an optimum focus location.

Abstract: A video camera includes a gate circuit for extracting a sharpness signal relative to an area which is set in a portion of a picture, a focus adjusting device for performing focus adjustment on the basis of the sharpness signal relative to the area, and an area selecting circuit for controlling the gate circuit to vary the area in size and determining a size of the area during a driving of a variator lens in accordance with a size of the area and a focal length used before the driving of the variator lens.

Abstract: An output from an auto focus sensor is converted into a digital signal by an A/D converting section, and an output from the A/C converting section is stored in a memory section. Further, a second AF arithmetic section is used to concurrently execute a plurality of focus detection arithmetic operations based on data in the memory section.

Abstract: A digital camera includes a CCD imager. If brightness of an object is not enough, a frame rate of the CCD imager at a time of a focus adjustment is changed from 30 fps to 15 fps. This also lowers a reading speed of a camera signal, and reduces noise included in the camera signal. An AF evaluation value is acquired by integrating a high frequency component of a Y signal generated on the basis of the camera signal, and therefore, high noise causes an error in the AF evaluation value and fails to correctly adjust focus. This is the reason why the driving speed of the CCD imager is lowered when the brightness of the object is not enough.

Abstract: A storage unit is configured to store beforehand a table that shows a relation between spread parameters and command values supplied to a control unit to acquire a focused image of an object, and information that designates a command value corresponding to an inflection point on an approximated curve showing the relation that the spread parameters have with the command values, the control unit being configured to control a state of an optical system in accordance with an input command value. The luminance information about the object that lies at a distance falling within a range over which focusing should be detected is acquired, at the position of the optical system, which is obtained by the command value corresponding to the inflection point shown in the table.

Abstract: In an imaging device according to one aspect of the invention, an amplitude demand Ac is specified according to a wobbling amplitude Ai required for detection of a hill-climbing direction based on an F value and a wobbling amplitude Ag required for detection of the hill-climbing direction based on an AGC gain. An allowable amplitude Am set for preventing a potential image shake caused by a magnification change with a position shift of a compensator lens in wobbling is specified corresponding to a zoom position and an object distance. When Ac>Am, the control procedure restricts the wobbling amplitude to Am and increases a sampling number of AF evaluation values to be detected at respective positions in wobbling, in order to ensure the sufficient detection performance of the hill-climbing direction. When Ac?Am on the other hand, the control procedure sets Ac to the wobbling amplitude.

Abstract: A lens-controlling device controls a first lens unit which moves for zooming and a second lens unit which moves for correcting the displacement of an image plane caused by zooming and for focusing. The lens-controlling device includes a memory which stores data for obtaining target-position information representing a target position to which the second lens unit is to be moved, the target position corresponding to a position to which the first lens unit is moved from a current position and a controller which generates the target-position information on the basis of the data and controls the movement of the second lens unit on the basis of position information of the first lens unit and the target-position information.

Abstract: An object of this invention is to provide an autofocus method and apparatus capable of always performing proper focusing operation. To achieve this object, a control device drives a focus lens in accordance with the operation of an operation device, and stores the stop position of the focus lens. While the focus lens is driven within a predetermined range using the stop position as a reference, the control device stores an output from an extraction device in association with the position of the focus lens. The control device determines the focusing state of the focus lens from the output from the extraction device, and when determining from the determination result that the focus lens is incapable of focusing, drives the focus lens to the stop position.

Abstract: An imaging apparatus including: an imaging device; a focusing operation control; and a decision control for comparing an evaluation value obtained from present image data with an evaluation value obtained from last image data obtained when the focus system leans was located at focal position in a last focusing operation and for deciding whether or not a focused state where the focus system lens is focused is maintained, according to a focusing instruction manipulation before performing the focusing operation and without driving the focus system lens.

Abstract: A focusing apparatus includes a filter unit for performing frequency filtering processing on an image pickup signal, and a focus position detecting unit for detecting a focus position based on the contrast value of the image pickup signal having undergone the frequency filtering processing by the filter unit. The filter unit has a first filter for normal position detection, and a second filter for infinity position detection having a frequency characteristic different from that of the first filter, and selects the first filter or the second filter.

Abstract: An image of a subject is taken by a solid image taking device including a first image taking element having a plurality of pixels and a second image taking element having a plurality of pixels smaller than those of the first image taking element. First and second evaluations on contrast obtained by integrating high-frequency components of first and second image signals representing an image of the subject taken by the first and second image taking elements are calculated. The focus is adjusted on the basis of the first and second evaluations on contrast so that the subject is imaged on the solid image taking device.

Abstract: The autofocus apparatus determines a focus position according to a result of sampling an AF evaluated value and drives a lens system to the focus position. This autofocus apparatus further performs a flash in synchronism with a sampling timing of an AF evaluated value.

Abstract: In one embodiment there is shown a method for capturing data, the method comprising sensing a first signal, capturing an auto exposure (AE) image in response to a sensed first signal, the auto exposure image captured with settings based upon preestablished criterion, and upon the AE image being captured, determining if a second signal has been sensed, and if the second signal has been sensed, capturing a speculative full exposure image, and if the captured speculative full exposure is determined to be acceptable, reading the remainder of the captured speculative image.

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: A focus detecting system for determining the focus state of an imaging lens, such as a camera lens, is disclosed. Object light not forming an image for image production is deflected along an optical axis through a relay lens to a focus state detection unit that includes image detecting elements with light receiving surfaces that are equidistant in front of and behind a position conjugate with a light receiving surface for image production. Either the relay lens or the focus state detection unit is moveable along the optical axis to vary how far the light receiving surfaces are out of focus. A diaphragm opening of the imaging lens determines if and by how much the relay lens and focus state detection unit are relatively moved. Evaluation values of the out of focus amount are compared in order to control focusing of the imaging lens.

Abstract: The present invention provides an AF evaluation value calculating device in which speed of AF control does not deteriorate even when a number of AF areas are set. The AF evaluation value calculating device for calculating an AF evaluation value used for AF (auto-focus) control of a digital camera, includes: at least one AF evaluation value calculating unit 13 for calculating an AF evaluation value in each of a plurality of AF areas which are set in an image area of image data supplied; and a data transmitter (17a and ch0) for transmitting the AF evaluation value calculated by the AF evaluation value calculator 13 into a predetermined memory by DMA (Direct Memory Access).

Abstract: Systems and method for determining, based on a gray scale image, focus of an imaging system. A method of this invention includes the steps of: a) acquiring a gray scale image of a test target, b) binarizing the acquired gray scale image, c) analyzing the binarized acquired image, d) adjusting focus of acquisition optics of the imaging system, and e) repeating steps a) through d) until a substantially maximum number of line pairs of a number of groups of line pairs of the test target is obtained, wherein each group from the number of groups of line pairs has a predetermined spatial frequency.

Abstract: In an iris image pickup method in which an image signal picking up an iris is allowed to pass through a high-pass filter (41L) and a lens position in which an output of the high-pass filter (41L) indicates a peak value is searched by a mountaineering method, thereby capturing an iris image focused on the iris, when an amount of a high luminance component included in the image signal is equal to or greater than a predetermined value, a peak position of a high frequency component in the image signal passing through a narrow-band high-pass filter (41H) for causing only a high band in a pass band of the high-pass filter (41L) to pass therethrough is obtained by searching for a whole area within a predetermined range in place of a search for a focusing position by the mountaineering method, and is set to be an iris focusing position. Consequently, it is possible to acquire a clear iris image having a high authentication rate which is focused on the iris in place of glasses.

Abstract: A camera includes: an image-capturing element that captures a subject image through a photographic lens having a focusing lens; an evaluation value calculation unit that calculates focus evaluation values at a plurality of lens positions assumed by the focusing lens based upon an image-capturing signal output by the image-capturing element; a weighting unit that weights the focus evaluation values calculated by the evaluation value calculation unit in correspondence to the lens positions of the focusing lens assumed when the focus evaluation values are calculated respectively; and a focusing operation unit that performs a focusing operation for the photographic lens based upon the weighted focus evaluation values.

Abstract: A camera comprising the following components is disclosed: a vibrating motor which drives a focus lens of an image-taking optical system, and a control circuit which controls the vibrating type motor to repeatedly drive and stop the focus lens, extracting higher frequency components from an image signal obtained from an image pickup device in each stopped state of the focus lens, and performing focus adjusting operation of moving the focus lens to an in-focus position in accordance with a focus adjustment state of the image-taking optical system determined on the basis of the higher frequency components. The control circuit causes traveling wave vibration to be generated on the vibrating member of the vibrating type motor when the focus lens is driven and causes standing wave vibration to be generated on the vibrating member while the focus lens is stopped during the focus adjusting operation.

Abstract: In a color separation optical system in a camera, subject light entering focus-imaging elements, to which optical path lengths from the taking lens are different, is obtained with a light dividing face. The focusing state is determined with focus evaluation values according to high frequency components of images captured by the focus-imaging elements. Thus, the focusing state can be quickly determined by a simple construction without using the wobbling method. The green light in the subject light entering the color separation optical system is transmitted through a blue light separation prism and a red light separation prism, and is divided into a reflected light and a transmitted light by a beam splitter face, which is a contact face between a first green light separation prism and a second green light separation prism. The light reflected on the beam splitter face exits from the color separation optical system as the subject light for determining the focusing state, and enters the focus-imaging element.

Abstract: Flash emission is required when image data have a low luminance value and when it is determined that flash emission is not prohibited, the built-in flash is used for autofocus (AF). An AF evaluation value is obtained under the flash emission, and the lens is driven based on this value. This operation is repeated until it is determined that the lens is focused, and accurate AF is executed even in dark conditions.

Abstract: The present invention relates to an electronic camera which images an object image and records image data. Particularly, the present invention relates to technology to record image data in a good shooting state, such as with little blurring due to hand shaking. The invention has an image pick-up means 1 which continuously images an object, a temporary memory means 2 which temporarily stores a plurality of frames of image data which are continuously imaged by the image pick-up means 1, a shooting evaluation means 3 which evaluates a good or bad shooting state of the image data imaged by the image pick-up means 1, a still image selection means 4 which selects the image data with the highest evaluation of the shooting evaluation means 3 among the image data which are stored in the temporary memory means 2, and an image saving means 5 which saves the image data which is selected by the still image selection means 4.

Abstract: This digital camera comprises a lens system (5) for focusing the image of a subject (10) on a sensitive plate (7), a control system formed, inter alia, by a motor (8) that act on the lens system to ensure a sharp image of the subject on the sensitive plate. To obtain this clarity of the subject on the plate, a first high-pass image filter (18) is used and a first low-pass image filter (15). As these filters also form part of the digital processing of image compression for recording the images, few additional means are to be provided for the automatic focusing that yields the clarity.

Abstract: It is an object of this invention to provide an image sensing method which allows object focus tracking during zooming regardless of the shutter speed. In order to achieve this object, a zoom motor for driving a zoom lens is controlled by a lens control microcomputer to decrease the zoom speed.