31results about How to "Accurate autofocus" patented technology

Auto focus systems and methods for a machine vision metrology and inspection system provide high speed and high precision auto focusing, while using relatively low-cost and flexible hardware. One aspect of various embodiments of the invention is that the portion of an image frame that is output by a camera is minimized for auto focus images, based on a reduced readout pixel set determined in conjunction with a desired region of interest. The reduced readout pixel set allows a maximized image acquisition rate, which in turn allows faster motion between auto focus image acquisition positions to achieve a desired auto focus precision at a corresponding auto focus execution speed that is approximately optimized in relation to a particular region of interest. In various embodiments, strobe illumination is used to further improve auto focus speed and accuracy. A method is provided for adapting and programming the various associated auto focus control parameters.

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.

A method, module, device, and computer program product for digital imaging. Providing an image within an image sensor, selecting at least one first region within image for scaling with a first scaling rate, selecting at least one second region within the image for scaling with a second scaling rate, and providing the first and the second regions for further processing allows improved autofocusing.

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; anda 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 lens autofocus actuating device includes a base, a guide rail unit, a lens carrier, an actuating member, a plurality of balls, and a shell. The base includes an upper surface. The guide rail unit is disposed on the upper surface of the base. The lens carrier is disposed above the base. The lens carrier is located between a plurality of position-limiting members. The actuating member is disposed on the upper surface of the base. The actuating member comprises two electrode terminal pairs and two shape-memory alloy wires. The balls are divided into groups. The shell is connected to the base.

The invention provides an auto-focusing method and a photographic device. The auto-focusing method comprises the following steps: an analog focusing system and a digital focusing system are built in the photographic device; and at least one of the analog focusing system and the digital focusing system is used for focusing during camera shooting or picture taking. According to the invention, analog filtering and digital filtering are performed on images acquired by camera shooting or picture taking, the advantages of the two focusing systems are felicitously combined, so that objects can be quickly and accurately determined to be focused, thereby realizing auto-focusing performance quickly and accurately.

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.

An autofocus method and system thereof provided by the present invention process the received video signal by frequency multiplication so that each first frame picture forms a first sub-frame picture and a second sub-frame picture in unit time, and then Determine the first focus area in a sub-frame picture and project the first focus image, and at the same time project the second focus image correspondingly in the second sub-frame picture, adjust the first focus image and the second focus image so that they are formed with the video signal The picture is equivalent, and then the focus parameters are obtained by continuously adjusting the focus of the first focus image, and the best focal length is obtained to complete the focus. This setting not only ensures that the projection device will not be affected by the external environment when focusing, but also ensures that the focus image inserted during focusing will not be noticed by human eyes, so as to avoid affecting the viewing experience of users and at the same time complete Precise autofocus.

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.

The present disclosure relates to an autofocus fundus camera, which includes: a light source for emitting a first light beam and a second light beam to the fundus of the eye, the first light beam is a light beam insensitive to the eye; a lens assembly; an imaging element for Receive the first light beam and the second light beam passing through the lens assembly; a recording module, which is used to record the first focus position when the first light beam is focused on the imaging element; a processing module, which is based on the wavelength of the first light beam and the diopter of the lens assembly Obtain the diopter of the eyeball with the first focus position, and obtain the second focus position after the second beam passes through the lens assembly based on the wavelength of the second light beam, the diopter of the eyeball and the diopter of the lens assembly; and the driving mechanism, which is based on the second focus The position adjusts the relative position between the lens assembly and the imaging element. According to the present disclosure, the fundus can be accurately auto-focused when the fundus image is collected, and the light stimulation to the eyes can be effectively reduced during the focusing process.

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.