Abstract: The ratio between an image A and an image B is calculated as the comparison result of the images A and B obtained from a pair of optical images. The variance is then calculated in order to evaluate the statistical fluctuation of the ratio obtained for each pixel. The fluctuation due to the variance is evaluated for each phase difference while the phase between the image A and the image B is shifted. The phase difference detection is performed on the basis of the evaluation result of the fluctuation.

Abstract: A digital camera has an optical system, an image capturing unit, an aperture adjuster, a focal point adjuster, and a body microcomputer. The aperture adjuster has an aperture included in the optical system and is capable of adjusting the state of the aperture. The focal point adjuster has a focus lens included in the optical system and is capable adjusting the focal state of the optical system by using the focus lens by contrast detection method. The body microcomputer controls the operation of the aperture adjuster so that the aperture value of the optical system will be at or below a set aperture value before the focal state is adjusted by the focal point adjuster.

Abstract: When the total number of pairs of a feature point and a corresponding point, which are detected from a first image data and a second image data that are in focus, respectively, exceeds a predetermined threshold th1, a parallax histogram generation unit is controlled to generate a histogram of parallax amount, and a representative parallax information determination unit is controlled to determine an amount of representative parallax from bins in the histogram of parallax amount. According to a search direction determined by a focus adjustment unit, the representative parallax information determination unit determines significance of each bin in the histogram based on whether a frequency f of the bin is greater than a predetermined threshold th2. The representative parallax information determination unit determines the amount of representative parallax based on amounts of parallax in the significant bin.

Abstract: An apparatus and method to track and to photograph a mobile object over a wide range, by a cooperative operation of multiple cameras. In addition, a mobile tracking system is provided for tracking the mobile object by the cooperation of multiple cameras, in which each camera includes a photographing device which photographs and recognizes the mobile object, a changing device which changes a view angle of the photographing device, a position deriving device which derives a position of the camera, a distance deriving device which derives the distance between the camera and the mobile object, and a communication device which transmits an identifier of the camera, a position of the camera, a moving direction of the mobile object and the distance between the camera and the mobile object to another camera and receives an identifier of the other camera, a position of the other camera, a moving direction of the mobile object and a distance between the other camera and the mobile object from the other camera.

Abstract: A system having a sensor and variable focus lens for iris image standoff acquisition. The sensor may capture a sequence of images at a high frame rate of a person for getting an eye or an iris in a window within the images. Even if the eye moves around in the image, the window may stay on the eye. During this capture, the focus of the lens may be changed, with a best focus situated somewhere in between the end focus positions of the lens. The sensor may be an infrared (IR) sensor and an IR illuminator or flash may provide light for the capture of images. An intensity variance indicator may be incorporated to select an in-focus image of the sequence. Processing of the images may be subsequent to the capture of images, thus not hindering the frame rate of the system.

Abstract: A focus control device includes: an in-detection-range focal depth number calculation section that calculates the number of in-detection-range focal depths as the number of focal depths, which are divided as division units and each of which depends on a position of a focus lens, in accordance with a detection range in which the focus lens is shifted in order to detect the contrast of a captured image signal; a detection interval determination section that determines the number of in-detection-interval focal depths, which represents the number of focal depths as the division units, as a detection interval in the detection range, in accordance with the calculated number of in-detection-range focal depths; and a focus lens shift instruction section that instructs a lens section to perform a focus search which shifts the focus lens by specifying the detection range and the number of in-detection-interval focal depths determined as the detection interval.

Abstract: An SLR camera having a focus detecting apparatus and a photographing method thereof are disclosed. The SLR camera may include an AF sensor, the pixels of which may be disposed in various arrangements, for example, in different sizes, in different gaps between the pixels and/or in different numbers, depending on the location of pixels and a control unit which controls the focusing operation based on the sampling levels output by the pixels.

Abstract: A focus detection apparatus includes an image pickup element 106 that takes an object image, an object recognition circuit 109 that compares an obtained image with a previously stored image to detect a position of a main object, an AF sensor 101 that detects an in-focus state of a plurality of positions, a reliability determination circuit 110 that determines a reliability of a detection result of the in-focus state, a determination part 100 that determines a position where the reliability of the detection result of the in-focus state is the highest based on a determination result of the reliability determination circuit, and a selector 114 that selects one of the detection results of the in-focus state of the position of the main object and of the in-focus state of the position where the reliability of the detection result of the in-focus state is highest to focus the photographic optical system.

Abstract: An image pickup apparatus includes an imaging element having a group of AF pixel pairs that realizes a pupil-dividing function and a group of normal pixels without such a pupil-dividing function. The image pickup apparatus performs focus control for driving a focus lens toward an in-focus position detected by phase different AF based on a pixel signal generated from the group of AF pixel pairs when it is determined that the reliability of the phase difference AF is high based on the pixel signal. The image pickup apparatus performs focus control for driving a focus lens in an in-focus direction detected by contrast AF based on a pixel signal generated from the group of normal pixels when it is determined that the reliability of the phase difference AF is low.

Abstract: Autofocusing is performed in response to a weighted sum of previous blur difference depth estimates at each focus adjustment iteration. Variance is also determined across both past and present estimations providing a confidence measure on the present focus position for the given picture. Focus adjustment is repeated until the variance is sufficiently low as to indicate confidence that a proper focus has been attained. The method provides more accurate and rapid focusing than achieved by the best current depth-based techniques, such as those utilizing most recent depth estimation to determine the next lens position. In contrast to this, the present apparatus and method combines all previous depth estimation results in the autofocus process to determine the next lens position based on statistical models and confidence measure.

Abstract: An imaging apparatus sets a main area and a plurality of subareas around the main area in an image obtained from an image sensor, and acquires each focusing state and each in-focus point based on the each focusing state of the main area and the plurality of subareas in an image obtained from the image sensor at each of a plurality of focus lens positions while moving a focus lens. If the focusing state of the main area does not satisfy a predetermined condition, the imaging apparatus performs focusing control using the focusing state of the main area and a focusing state of a subarea having an in-focus point located within a predetermined range from the in-focus point of the main area among the plurality of subareas.

Abstract: A digital photographing apparatus that supports a fast multi-autofocusing (AF) method, in which, when AF peaks of a subject of a central multi-point and a subject of a nearest multi-point are detected, further scanning is not performed. In addition, scanning is not performed on a region from which it is difficult to detect a peak, so that fast and accurate AF may be performed.

Abstract: Autofocusing is performed in response to a weighted sum of previous blur difference depth estimates at each focus adjustment iteration. Variance is also determined across both past and present estimations providing a confidence measure on the present focus position for the given picture. Focus adjustment is repeated until the variance is sufficiently low as to indicate confidence that a proper focus has been attained. The method provides more accurate and rapid focusing than achieved by the best current depth-based techniques, such as those utilizing most recent depth estimation to determine the next lens position. In contrast to this, the present apparatus and method combines all previous depth estimation results in the autofocus process to determine the next lens position based on statistical models and confidence measure.

Abstract: A circuit for calibrating a focus position of an optical module includes a calibration signal generating unit and a focus position adjusting unit. The calibration signal generating unit is utilized for generating a calibration signal according to a first focus signal and a second focus signal at the same time, where the first focus signal and second focus signal correspond to a first focus position and a second focus position, respectively, and the first focus position is different from the second focus position. The focus position adjusting unit is coupled to the calibration signal generating unit and is utilized for adjusting the focus position of the optical module to a specific focus position according to the calibration signal.

Abstract: An image-pickup apparatus is disclosed which is capable of restricting unnecessary focus control by an AF method other than the TV-AF method in the hybrid AF. The image-pickup apparatus includes a first detector which generates first information corresponding to a contrast state of a picked-up image, a second detector which detects second information differing from the first information and used for focus control, and a controller which performs focus processing that cyclically repeats first focus control using the first information and performs second focus control using the second information. In the focus processing, the controller is changed over between a state of restricting the second focus control and a state of allowing the second focus control, depending on a change amount of the contrast state.

Abstract: A monitoring system includes: an image capturing section capturing a motion image of a monitor region; a condition storing section storing a condition of an object to be extracted from the motion image; a matching judging section judging whether an object that matches the condition exists in the motion image; an object region identifying section identifying an object region including the object, if the matching judging section judges positively; an output section outputting an image of the object region, if the matching judging section judges positively; an image retaining section retaining an image of a region other than the object region, if the matching judging section judges positively; and an output control section controlling the output section to output the image of the region, if the image of the region is judged to be transmitted, after the image retaining section retained the image of the region.

Abstract: A focus detecting device includes a focus detecting optical system which forms a plurality of object images. A photoelectric conversion element array includes a plurality of pixels and subjects each of the plural object images formed by the focus detecting optical system to photoelectric conversion. An electric charge transfer path transfers an electric charge obtained by the photoelectric conversion subjected by the photoelectric conversion element array. A focus detecting section performs focus detection with respect to a plurality of focus areas on the basis of a signal associated with an electric charge transferred by the electric charge transfer path. A plurality of effective pixel regions corresponding to the plural focus areas are arranged in the arrangement direction of the pixels of the photoelectric conversion element array, and ineffective pixel regions are arranged between the plural effective pixel regions.

Abstract: A method and apparatus to auto focus are provided. A distance classifier to auto focus includes a distance-calculating module calculating a focal distance on the basis of blur levels of at least two images; a precise distance-calculating module calculating the exact distance to a subject when an image that is captured at the focal distance calculated by the distance-calculating module is out of focus; and a distance-calculation-correcting module correcting the distance-calculating module on the basis of the blur levels and the exact distance to the subject that is calculated by the precise distance-calculating module.

Abstract: An imaging apparatus which includes a focus detection unit performing focus detection in a contrast system, and a display unit displaying the image obtained from an imaging unit in live view display is provided. The imaging apparatus includes a setting member setting a contrast AF calibration mode, a calibration amount obtaining unit for obtaining a difference amount between a focus position selected by a photographer and an in-focus position by the focus detection unit as a contrast AF calibration amount when the focus position is selected by the photographer in the contrast AF calibration mode, a storage unit storing the contrast AF calibration amount, and a focus control unit performing in-focus control by adding the contrast AF calibration amount to the in-focus position by the focus detection unit at the time of shooting while performing the in-focus control based on a result of the focus detection by the focus detection unit.

Abstract: An image capturing apparatus includes an image sensor having a focus detection pixel group including a plurality of focus detection pixels that receive light passing through a part of a pupil area of an imaging lens for forming an object image and an image forming pixel group including a plurality of image forming pixels that receive light passing through the whole of the pupil area of the imaging lens; and an image processing unit that generates an image signal corresponding to the position of each of the focus detection pixels by using at least either of a signal of the focus detection pixel at the position and signals of neighboring image forming pixels of the focus detection pixel at the position, depending on the size of an aperture of the focus detection pixels.

Abstract: High-accuracy focus adjustment is achieved even when vignetting is caused by a taking lens. A first pixel group receives a light beam that passes through a first pupil area of an optical system that forms an object image, and a second pixel group receives a light beam that passes through a second pupil area. A first signal based on an output signal from the first pixel group and a second signal based on an output signal from the second pixel group are corrected using correction information with a sampling pitch that is changed in accordance with an amount of defocus. A focal state of the optical system is adjusted based on an amount of relative displacement between the corrected first signal and the corrected second signal after the image-signal correction process.

Abstract: An image apparatus includes a screen, a detecting unit, a determining unit, an acquiring unit and a control unit. The screen is configured to display an image formed by an optical system and at least one detection position superimposed onto the image. The detecting unit is configured to detect information regarding focus of the optical system at the detection position. The determining unit is connected to the detecting unit and configured to determine whether the information regarding the focus is within a predetermined range. The acquiring unit is connected to the determining unit and configured to acquire first image information at the detection position when the determining unit determines that the information regarding the focus is within the predetermined range. The control unit is connected to the acquiring unit and configured to evaluate arbitrary second image information in the screen using the first image information.

Abstract: A focal point detection device includes a focal point detection section which detects a focal point state of an object image corresponding to each of focal point detection regions. A group selection section selects focal point detection regions as a group. A judgment section determines a focal point detection region in which detection of the focal point state is enabled in the selected group. An automatic focal point detection region selection section selects, when detection of the focal point detection regions can be performed in the selected group, a focal point detection region in the selected group, and selects, when detection of the focal point detection regions cannot be performed, a focal point detection region outside the selected group. A control section drives an imaging optical system in accordance with the focal point state corresponding to the focal point detection region selected.

Abstract: A focus detecting apparatus includes a splitter for splitting a light from an image pickup lens to form at least a pair of images, a photoelectric conversion element for photoelectrically converting at least the pair of images, the focus detecting apparatus detecting a focusing status of the image pickup lens based on a signal from the photoelectric conversion element, and a light blocking mask for blocking the light from entering the photoelectric conversion element, the light blocking mask having a curve shape in a moving direction of the image that varies according to an image height.

Abstract: When the total number of pairs of a feature point and a corresponding point, which are detected from a first image data and a second image data that are in focus, respectively, exceeds a predetermined threshold th1, a parallax histogram generation unit is controlled to generate a histogram of parallax amount, and a representative parallax information determination unit is controlled to determine an amount of representative parallax from bins in the histogram of parallax amount. According to a search direction determined by a focus adjustment unit, the representative parallax information determination unit determines significance of each bin in the histogram based on whether a frequency f of the bin is greater than a predetermined threshold th2. The representative parallax information determination unit determines the amount of representative parallax based on amounts of parallax in the significant bin.

Abstract: A focus detection device comprises: focus detection elements including light-receiving elements that generate a pair of signals corresponding to a pair of light fluxes each passing through an imaging optical system that includes a lens and an aperture stop; and a focus detector including a processor that determines a focus adjustment state of the imaging optical system with an f-number slower than a full-aperture of the imaging optical system when a specific condition is fulfilled.

Abstract: An autofocus method for obtaining clear images characterized by: adjusting the lens position with an initial dataset of focus values to obtain a estimated lens position; moving the lens to the estimated lens position and acquiring the corresponding focus value; determining whether the estimated lens position is sufficiently proximate to the prior estimated lens position, wherein, if it is, the autofocus process stops, and, if not, repeating the above-described steps until a lens position having an optimal focus value is obtained, thereby obtaining the clearest image with increased focusing speed and reduced time of lens movement and without the need of empirical parameters.

Abstract: An imaging apparatus includes: a face detecting part configured to detect a face area from the input image inputted from an imaging apparatus; a subject distance computing part configured to compute a subject distance based on the size of a face detected in the face detecting part; a lens operating range computing part configured to estimate a focus position based on information about the subject distance computed in the subject distance computing part, and to set a focus lens operating range shorter than an entire operating range of a focus lens; and a focus control part configured to move the focus lens within the lens operating range set in the lens operating range computing part, and to decide a position at which the focus lens is set.

Abstract: An imaging device includes an autofocusing section, which moves at least a part of an imaging lens as a focusing lens, and focuses the imaging device on a subject, a photographing distance range setting section, which sets a predetermined distance range including a subject distance to the subject obtained by the autofocusing section as a photographing distance range for photographing, a continuous shooting section, which continuously photographs at a plurality of focused positions in the photographing distance range while moving and stopping the focusing lens according to input of a photographing instruction, and a display section, which displays an image of the subject focused by the autofocusing section and the photographing distance range set by the photographing distance range setting section.

Abstract: An automatic focusing apparatus includes: a focus detector photoelectrically converting at least a part of a photographing beam; a defocus computer calculating a defocus amount based on an output of the focus detector; a driver driving a focus lens based on the defocus amount; and a unit setting a maximum time period for charge accumulation in the focus detector. If the accumulated charge in the focus detector reaches a threshold within the period, when the accumulated charge in the focus detector reaches the threshold, the defocus computer calculates a defocus amount using an output of the focus detector and outputs the defocus amount to the driver. If the accumulated charge in the focus detector does not reach the threshold within the period, when the period lapses, the defocus computer calculates a defocus amount using an output of the focus detector and outputs the defocus amount to the driver.

Abstract: An image-pickup apparatus is disclosed which is capable of restricting unnecessary focus control by an AF method other than the TV-AF method in the hybrid AF. The image-pickup apparatus includes a first detector which generates first information corresponding to a contrast state of a picked-up image, a second detector which detects second information differing from the first information and used for focus control, and a controller which performs focus processing that cyclically repeats first focus control using the first information and performs second focus control using the second information. In the focus processing, the controller is changed over between a state of restricting the second focus control and a state of allowing the second focus control, depending on a change amount of the contrast state.

Abstract: In an automatic focus adjusting mechanism, a test sample having a patterned surface is mounted on a mount table, and an light beam passing through a slit formed in a field stop is applied to the patterned surface of the test sample. The light beam reflected from the test sample is split into two segment light beams. Focus adjusting aperture stops having respective apertures formed rhomboid are provided across the optical paths of the segment light beams. The amounts of the segment light beams passing through the rhomboid apertures are detected by light receiving units. Based on the difference between the detected light amounts, the position of the mount table is controlled by the focus adjusting unit.

Abstract: An imaging apparatus comprising: a light receiving element having a micro lens array provided with a plurality of micro lenses arranged two-dimensionally, and a plurality of photoelectric conversion elements provided for the plurality of micro lenses, and outputting a light receiving signal obtained by receiving a light beam from an optical system via the micro lens array; a detector that detects shift amounts of image plane by the optical system respectively for a plurality of focus detecting positions set at a plurality of positions in the image plane by the optical system; and a controller that determines a focus adjusting position for the optical system based on a plurality of the shift amounts detected respectively for the plurality of focus detecting positions and a range of the image plane where an image based on the light receiving signal is enabled to be produced, and obtains the light receiving signal at the focus adjusting position with the light receiving element.

Abstract: A circuit for calibrating a focus position of an optical module includes a calibration signal generating unit and a focus position adjusting unit. The calibration signal generating unit is utilized for generating a calibration signal according to a first focus signal and a second focus signal at the same time, where the first focus signal and second focus signal correspond to a first focus position and a second focus position, respectively, and the first focus position is different from the second focus position. The focus position adjusting unit is coupled to the calibration signal generating unit and is utilized for adjusting the focus position of the optical module to a specific focus position according to the calibration signal.

Abstract: An optical apparatus which achieves fast focusing operation and allows accurate focusing is disclosed. The optical apparatus includes a first focus detector which detects a focus state on a subject, a second focus detector which detects a focus state on the subject in a detection method different from a detection method of the first focus detector, and a controller which has a function of detecting whether or not the subject is a moving body and a function of performing focus control of an image-taking optical system in a first sequence in which at least one of the first and second focus detectors is used and a second sequence in which at least the other of the focus detectors is used. The controller preferentially uses one of the first and second sequences depending on the result of the detection with the moving body detecting function.

Abstract: An image-pickup apparatus is disclosed which is capable of restricting unnecessary focus control by an AF method other than the TV-AF method in the hybrid AF. The image-pickup apparatus includes a first detector which generates first information corresponding to a contrast state of a picked-up image, a second detector which detects second information differing from the first information and used for focus control, and a controller which performs focus processing that cyclically repeats first focus control using the first information and performs second focus control using the second information. In the focus processing, the controller is changed over between a state of restricting the second focus control and a state of allowing the second focus control, depending on a change amount of the contrast state.

Abstract: An image-pickup apparatus includes a first detector generating first information corresponding to a contrast state, a focus lens controller, a second detector outputting second information used for calculating an in-focus position, and a focus lens position detector. If the difference between the detected focus lens position and the calculated in-focus position is equal to or greater than a first value, the controller moves the focus lens towards the calculated in-focus position, and if the difference is less than the first value, the controller repeats focus control using the first information without using the second information. The apparatus reduces discontinuous movements of the focus lens.

Abstract: In an imaging device, a photographic scene is automatically determined with high accuracy. Distance information is acquired, through a TTL-AF, from an image signal produced by a CCD. Further, a face recognition circuit detects the face of a person in a subject. An AE-AF-AWB value computing section evaluates the reliability of the distance information acquired through the TTL-AF operation, on the basis of a focal length of a lens, an aperture, and a distance to the subject computed from a distance between eyes included in the detected face. A mode-recognition-and-determination-and mode-selection section automatically determines the photographic scene from the distance information acquired through the TTL-AF operation, the reliability of the distance, and an estimated white balance value.

Abstract: An SLR camera having a focus detecting apparatus and a photographing method thereof are disclosed. The SLR camera may include an AF sensor, the pixels of which may be disposed in various arrangements, for example, in different sizes, in different gaps between the pixels and/or in different numbers, depending on the location of pixels and a control unit which controls the focusing operation based on the sampling levels output by the pixels.

Abstract: An image forming state detection device comprises a micro-lens array that is disposed at a position set apart from a predetermined focal plane of an image forming optical system by a specific distance and includes a plurality of micro-lenses arrayed with a predetermined pitch, a light-receiving portion array that includes a plurality of light-receiving portions each corresponding to one of the micro-lenses in the micro-lens array and receives an image on the predetermined focal plane via the individual micro-lenses, a signal string extracting means that extracts a pair of signal strings corresponding to images, formed with light fluxes having passed through different pupil areas of the image forming optical system, based upon light reception outputs obtained from the plurality of light-receiving portions, and an image forming state calculating means that calculates an image forming state at the image forming optical system by detecting an offset with regard to the phases of the pair of signal strings extracte

Abstract: An image pickup apparatus includes an imaging element having a group of AF pixel pairs that realizes a pupil-dividing function and a group of normal pixels without such a pupil-dividing function. The image pickup apparatus performs focus control for driving a focus lens toward an in-focus position detected by phase different AF based on a pixel signal generated from the group of AF pixel pairs when it is determined that the reliability of the phase difference AF is high based on the pixel signal. The image pickup apparatus performs focus control for driving a focus lens in an in-focus direction detected by contrast AF based on a pixel signal generated from the group of normal pixels when it is determined that the reliability of the phase difference AF is low.

Abstract: A camera with a photographing optical system, including a focus adjusting system which captures images at different focal positions via an image pickup device while moving a focusing lens group within a controllable searching range, and moves the focusing lens group to the in-focus position; a memory which stores a first image captured when an in-focus state is achieved; and a comparing device which compares the first image stored in the memory with a second image captured via the image pickup device before commencement of movement of the focusing lens group. The focus adjusting system operates within a limited searching range including a current position of the focusing lens group when predetermined conditions are satisfied, including a condition upon which it is determined that the first image and the second image match each other completely or by a predetermined degree.

Abstract: When focus adjustment operation is performed, a first measured distance acquired by utilization of TTL-AF and a second measured value acquired by utilization of a distance between the eyes have been computed in advance. The degree of reliability of the first measured distance is compared the degree of reliability of the second measured distance in accordance with a result of a determination as to whether or not a face is detected, a result of a determination as to whether or not an ambient brightness value Br is equal to or less than a reference value, a result of a determination as to whether or not a focal length “f” is equal to or less than a reference value, and a result of a determination as to whether or not a second measured distance De is less than a first measured distance Dt.

Abstract: A photographing apparatus and method prevent a resolution of a peripheral portion of an image from being degraded with a simple structure. These employ an in-focus state detector for detecting evaluation values for auto in-focus operation representing an in-focus state of an image from a first in-focus state detection region disposed on a center portion of the image, and at least one second in-focus state detection region disposed on a peripheral portion of the image, a flat subject determiner that determines whether a subject is flat based on the detection result of the evaluation values for auto in-focus operation, a flat subject focusing position calculator that calculates a final focusing position based on the evaluation values when the subject is determined as being flat, and a three-dimensional subject focusing position calculator that calculates a final focusing position based on the evaluation value when the subject is not flat.

Abstract: There is disclosed a digital camera which detects a focus of a lens unit by a method selected from a plurality of focus detection methods based on information on the lens unit taken from the lens unit attached to the digital camera. As an example of a focus detection method, there is a method by a phase difference system or a contrast system, but the method is not limited to this example.

Abstract: A digital camera includes a phase difference AF sensor unit, phase difference AF detection unit, contrast AF detection unit, lens driving unit which focuses a taking lens, shading determination unit which determines based on lens information of the taking lens whether focus detection by the phase difference AF sensor unit is possible, and an AF control unit. The AF control unit cause the lens driving unit to focus the taking lens based on a focus detection result of the phase difference AF detection unit when the shading determination unit determines that the focus detection by the phase difference AF sensor unit is possible, and causes the lens driving unit to focus the taking lens based on a focus detection result of the contrast AF detection unit when the shading determination unit determines that the focus detection by the phase difference AF sensor unit is not possible.

Abstract: An automatic focusing apparatus detects presence or absence of change in a distance between an object and the automatic focusing apparatus while operating in an operation mode to continuously perform an adjustment of the position of a focus lens to focus on the object, and stops a movement of the focus lens if a change in the distance is not detected.

Abstract: An autofocus apparatus includes an imaging unit configured to capture an object image entered through a focus lens and output image data, a detection unit configured to detect a focus signal based on the image data, a focus adjustment unit configured to perform a focus adjusting operation for adjusting a position of the focus lens based on the detected focus signal, an acquisition unit configured to acquire information relating to a distance to an object, and a change unit configured to change at least one of a time interval, a movable range of the focus lens in acquiring the focus signal in the subsequent focus adjusting operation, and an amount of movement of the focus lens in acquiring the focus signal in the subsequent focus adjusting operation, according to the information relating to the distance to the object.

Abstract: A focus adjustable method of an optical image is implemented by a numerical analysis. An external light beam is allowed to pass through a lens module, thereby generating an optical image. The focus values of the optical image at four corners thereof are computed according to specified formulas to obtain a two-dimensional geometric tilt vector T(X,Y), an image diagonal spinor D and an image tetragonal average value M. According to the values T(X,Y), D and M, the tilt amount and the tilt direction of the lens module are adjusted, the optical quality of the lens module is discriminated and the focus value distribution of the lens module is determined.

Abstract: Imaging systems and methods for calibrating imaging systems are provided. The imaging system has a body, a scene image capture system that captures images using a taking lens system that can be set to a plurality of different focus distances, and a rangefinder that is capable of determining a distance between the imaging system and at least one portion of a field of view of the taking lens system. The method comprises: automatically capturing a first calibration image of a first field of view through the taking lens system with the taking lens system set to a first focus distance setting; identifying a portion of the first calibration image having a predetermined degree of focus; using the rangefinder to determine a first calibration distance from the imaging device to the identified portion. A focus correlation is determined based upon the first calibration distance and the first focus distance setting.