30results about How to "Accurate autofocus" patented technology

In addition to an autofocusing operation performed under visible light, an autofocusing operation is also performed under infrared light. By using infrared light, changes in the contrast can be detected accurately regardless of the character of the image. As a result, the focused position can be detected with a high degree of accuracy even in a dark image or an image in which the character of the image changes drastically. In addition, by ascertaining the difference between the infrared light focused position and the visible light focused position and correcting with the infrared light focused position, a focused matched position can be detected with an even higher degree of accuracy.

The invention relates to an automatic focusing method for an electric adjustable liquid lens. According to the method, a target image is obtained through an image sensor; pretreatment is carried out on the image to eliminate the effects on the focusing process caused by light and noise; after a user selects a focusing region, a tracking unit tracks the focusing region and calculates a definition value of the region to feed back to a focusing control unit; and the focusing control unit carries out judgment according to the change condition of the definition value and drives the liquid lens to change the focus distance to finish focusing through an electric adjustable liquid lens driver. An optical component does not need to relatively displace when focusing, so that the focusing speed is high; and the effects of compact structure and long service lifetime of an automatic focusing system can be achieved.

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.

The invention relates to an automatic SUSAN (Smallest Univalue Segment Assimilating Nucleus) focusing method for a video monitoring system, which is used for maintaining a position of an optical lens invariable, and adjusting a target surface position of an image detector to an optimal imaging position along an optical axis. The method comprises the following steps that an improved SUSAN edge extraction algorithm is adopted to serve as a definition evaluation function in an automatic focusing process, and an adaptive variable step size hill climbing algorithm is adopted to serve as an optimal definition value position searching algorithm in the automatic focusing process. As an SUSAN operator is improved to serve as the definition evaluation function in the automatic focusing process, the automatic SUSAN focusing method for the video monitoring system has good unimodality, unbiassedness and keenness, and also has good noise immunity and good real time. When the method is applied to automatic focusing in the video monitoring system, the automatic focusing of the system can be realized quickly and accurately.

An automatic focusing system comprising: a plurality of image pickup surfaces of an AF image pickup device for taking images of a subject for performing automatic focusing of a picture taking lens, the image pickup surfaces being placed at such positions that the length of optical paths to the image pickup surfaces differ from each other; a common optical path which is a portion of an optical path through which subject light entering the picture taking lens are supplied to the plurality of image pickup surfaces, and through which the entire subject light to be incident on the image pickup surfaces passes; a light splitting device which splits the subject light supplied through the common optical path into subject lights respectively incident on the plurality of image pickup surfaces; a focusing control device which controls focusing of the picture taking lens on the basis of contrasts in the subject images obtained through the plurality of image pickup surfaces so that a correct focus on the subject is achieved; and a conversion device which is placed at a predetermined position in the common optical path, and which converts the subject light reaching the predetermined position into non-polarized light if the subject light is polarized light, and makes the converted subject light enter the light splitting device.

A video camera constructed according to one aspect of the focus adjustment device moves a focus lens forward and backward and detects peak values of an AF evaluation value of the focus lens in the forward moving direction and in the backward moving direction. The video camera calculates a correction value based on a difference between the peak value of the evaluation value detected in the forward motion of the lens and the peak value of the evaluation value detected in the backward motion of the lens. The video camera corrects the AF evaluation value with the calculated correction value and detects a focused position of the lens based on the corrected AF evaluation value in moving the lens.

A projection display apparatus is provided with a control unit that drives a focus lens included in a projection lens based on outputs from a focus sensor and a temperature sensor. The control unit provided in the projection display apparatus compensates the output value of the temperature sensor according to the amount of change in the output value of the temperature sensor with time and drives the focus lens using the value thus compensated.

In digital imaging, in a case where the full resolution digital image needs to be scaled down before presenting it on a display, before the image is scaled down, statistical data is gathered from said the full resolution image data, whereby the gathered statistical data is attached to the image for further processing. The invention relates to a method, to a device, to an imaging module and to a computer program product.

A controller controls a focus lens driver so as to maintain an in-focus state associated with a magnification variation, based on information on a tracking curve that represents a position of the focus lens corresponding to an object distance and a focal length of an image-pickup optical system. The controller controls the focus lens driver so as to prevent the focus lens from being moved for focusing based on a difference between an actual position of the focus lens and the position of the focus lens indicated by the tracking curve in a case the focus lens driver is driving the focus lens based on information on the tracking curve.

The invention provides display equipment which realizes automatic focusing and a displaying control method thereof. The display equipment comprises the components of a projection unit which is used for supplying an imaging optical signal to be displayed; a lens unit through which the imaging optical signal forms the to-be-displayed image on an imaging surface; a focusing and light-emitting unit which is configured on the imaging surface and is used for transmitting a focusing optical signal to the lens unit; and a focusing sensing unit which is used for sensing the focusing optical signal that enters through the lens unit and controlling movement of the lens unit according to the imaging state of the focusing optical signal, wherein an optical path between the projection unit and the lens unit is equal with that between the focusing sensing unit and the lens unit.

The invention discloses an automatic adjusting jig for focusing of a fixed-focus lens and an adjusting method of the automatic adjusting jig. The adjusting jig comprises a machine base, a rotating device, a driving device and a control device, wherein the control device has an electronic input interface used for acquiring image sharpness information of the lens and an electronic output interface that outputs a rotation direction and a rotation step length signal, the electronic output interface is connected to the driving device, the driving device and the rotating device are mounted on the machine base, the rotating device is provided with a mechanical rotating interface used for being connected with the lens, and the driving device is connected to the rotating device to drive the rotating device to rotate the fixed-focus lens according to the rotation direction and the rotation step length signal. Thus, the whole process does not need the participation of people, so that the workload of operating personnel is reduced, the production efficiency is greatly improved, artificial costs are reduced, the problem of a yield rate caused by visual fatigue of the operating personnel is prevented, and the yield rate is effectively improved.

The invention discloses an automatic focusing device and a method. The automatic focusing device adjusts the position of an objective lens via a first laser, a first optical fiber coupler, a second laser, a second optical fiber coupler, a third optical fiber coupler, a single-mode optical fiber, an alignment element, the objective lens, a semi-transmitting and semi-reflecting mirror, a relay mirror, a CCD/CMOS imaging device, a first photoelectric detector, a second photoelectric detector and a controller. Automatic focusing can be realized quickly and accurately, and the problems of multiple times of operation and slow focusing speed during a picture photographing process can be solved.

The auto focusing method for a digital image acquisition device comprises: A. selecting the initial movement direction for lens, let it move to a position; let r = 0 and s = 1; B. calculating and recording corresponding boundary information of current lens position; C. deciding whether it has found out the maximal value of information value; if yes, determining current lens position as the accurate focus position, the process ends; D. if meeting lens deflecting condition, let lens movement direction as the inverse one for current movement, let s = 0 and r = r+1; E. if r>1, taking lens position with known maximal boundary information value as the focusing position, the process ends; F. moving lens along preset direction, let s = s+1, and turning to step B.

The invention discloses an automatic focusing method and device. The automatic focusing method comprises the following steps that illumination light emitted by a light source is reflected to pilot light in a sample; the pilot light is divided into first and second pilot light by semi-reflection semi-transmission, the reflected first pilot light is obtained behind a reflection light focusing position, and the reflected second pilot light is obtained in front of a transmitted light focusing position; a driving signal S is obtained by calculation; the defocusing quantity of the sample is calculated according to the driving signal S; and an object lens is driven to focus according to the defocusing quantity. The pilot light reflected by the sample is divided into two paths of pilot light, thetwo paths of pilot light are obtained in different positions, two signals are obtained after processing, the defocusing quantity of the sample is obtained by calculating a difference of the two signals, and the object lens is driven to implement accurate focusing after that the defocusing quantity is known. The focusing method and device simplify design of the optical path, signal calculating is simpler, the defocusing quantity can be calculated rapidly and accurately, and the object lens can be focused automatically, rapidly and accurately.

The invention relates to an automatic focusing method. The method comprises the following steps: controlling a first driving module to drive a first image acquisition module to perform automatic focusing on a target object through a preset mode; acquiring a first driving quantity of the first driving module to the first image acquisition module; querying a second driving amount associated with the first driving amount according to a preset association relationship; and controlling the second driving module to drive the second image acquisition module to perform automatic focusing on the target object according to the second driving amount. According to the embodiment of the invention, compared with automatic focusing modes such as contrast focusing, phase focusing and double-shooting focusing in the related technology, automatic focusing can be accurately carried out under the condition that ambient light is dark, and compared with an automatic focusing mode of laser focusing in the related technology, the method can be applied to accurate automatic focusing of more types of objects.

The invention discloses a method for dynamically adjusting a frame rate to optimize automatic focusing. The method comprises the following steps: decomposing a focusing window into a plurality of focusing sub-windows, and simultaneously acquiring a frame rate parameter and an exposure parameter of each focusing sub-window; performing credibility weighted calculation and adjustment on the frame rate parameter and the exposure parameter of each focusing sub-window to obtain an automatic focusing adjustment parameter set; respectively and dynamically adjusting the current frame rate parameter and the exposure parameter based on the light value of the current frame; and carrying out frame synchronous motor driving based on the acquired multiple operation parameters, obtaining the focusing statistical data of the current frame, and completing automatic focusing based on the calculated focusing position until all the frames are processed, so that accurate automatic focusing can be carried out according to the light of the current environment.

An auto-focus apparatus and an auto-focus method are provided. The auto-focus apparatus includes: a lens, a lens driving component, and a focus control module; wherein the lens is configured to guide light transmitted from a target object; wherein the lens driving component is configured to drive the lens to move to the multiple positions to obtain the original images, and drive the lens to a focusing position obtained by the focus control module; and wherein the focus control module is configured to obtain frequency respond results each of which corresponds to interested pixels in one of the original images, calculate a desired frequency respond result based on the obtained frequency respond results and take a first position of the lens corresponding to the desired frequency respond result as the focusing position. Accordingly, focus accuracy and focus speed under conditions of poor contrast texture and weak light are improved.