15 results about "Focus measure" patented technology

A system and method for reviewing a tomosynthesis image data set comprising volumetric image data of a breast, the method comprising, in one embodiment, causing an image or a series of images from the data set to be displayed on a display monitor and selecting or indicating through a user interface an object or region of interest in a presently displayed image of the data set, thereby causing an image from the data set having a best focus measure of the user selected or indicated object or region of interest to be automatically displayed on the display monitor.

The invention provides an X-ray tube focus measuring tool. The X-ray tube focus measuring tool comprises a base, an outer cylinder and a top cover. Wherein the base comprises a first cylindrical supporting part and a second cylindrical supporting part, and the top of the second supporting part is sunken downwards to form a first containing groove. A clamping device is arranged in the first containing groove, and a clamping hole is formed in the center of the clamping device in the vertical direction in a penetrating mode and used for fixing the X-ray tube. The outer cylinder is arranged on the upper surface of the first supporting part. And exhaust holes are formed in the surface of the outer cylinder in a penetrating manner. The top cover is matched with the upper opening of the outer cylinder in shape. The upper surface of the top cover sinks downwards to form a second containing groove, a light-transmitting window is formed in the center of the second containing groove, a focus test block is arranged in the second containing groove, and a light-transmitting seam is formed in the lower surface of the focus test block and used for transmitting X-rays. According to the technical scheme, the split type design is adopted, the position and direction of the X-ray tube can be kept stable in the insulating oil environment, thermal expansion can be effectively compensated, and the positioning stability is improved.

Systems, methods, and apparatuses are provided herein for changing the positions and / or shapes of microlenses of a light field camera to generate light field images with enhanced depth of field and / or dynamic range. This may be accomplished by a light field camera determining a plurality of focus measurements for a plurality of microlenses, wherein one or more of the plurality of microlenses vary in distance from a main lens of the light field camera. The light field camera may use the plurality of focus measurements to determine a microlens of the plurality of microlenses that captures information that is the most focused. The light field camera can then determine defocus functions for the microlenses that are not capturing information that is the most focused. The light field camera can then generate a light field image using the determined defocus functions and the information captured by the plurality of microlenses.

The invention relates to the technical field of X-ray focus measurement, and particularly discloses an X-ray focus measurement analysis method, device and system, and the method comprises the steps: obtaining a focus image formed by a photon detector which can capture X-rays emitted by an X-ray bulb tube through a pinhole diaphragm, and forming the focus image; performing image preprocessing on the focus image to obtain a preprocessed focus image; determining an actual image focus position in the preprocessed focus image; determining a target disc focus offset according to the actual focus position of the image and an imaging principle formed between the photon detector and the X-ray bulb tube; and performing focus stability analysis according to a plurality of target disc focus offsets formed by the plurality of focus images to obtain a focus jitter quantitative analysis result. According to the X-ray focus measurement and analysis method provided by the invention, the size of the focus irradiated on the target disc by the X-ray bulb tube can be measured, and meanwhile, the deviation of the focus position can be detected.

This invention relates to the field of CT detection technology, and particularly to a micro / nano CT X-ray source focus measurement device and method. This application proposes a micro / nano focus measurement method based on the stacked edge method and designs a corresponding measurement device. A micro / nano focus measurement model is constructed using EGSnrc Monte Carlo simulation, analyzing the influence of different magnifications on the measurement results of 1μm and 2μm nominal focuses. It is determined that the magnification of a 1μm focus should be no less than 600 times, and the magnification of a 2μm focus should be no less than 300 times. Simultaneously, it is clarified that when the number of projected pixels of the focus on the detector is no less than 7.39 pixels, the measurement error can be controlled within 10%. Experimental verification results show that the measurement results of this application deviate from those of the JIMA card edge method by less than 1%, and the asymmetric distribution characteristics of the focus can be clearly reconstructed.

The present invention relates to the field of X-ray focus measurement technology, and specifically discloses an X-ray focus measurement and analysis method, device, and system, including: obtaining a focus image formed by a photon detector, wherein the photon detector is capable of capturing X-rays emitted by an X-ray tube through a pinhole aperture and forming a focus image; performing image preprocessing on the focus image to obtain a preprocessed focus image; determining the actual focus position of the image in the preprocessed focus image; determining the target disk focus offset based on the actual focus position of the image and the imaging principle formed between the photon detector and the X-ray tube; performing focus stability analysis based on multiple target disk focus offsets formed by multiple focus images to obtain focus jitter quantitative analysis results. The X-ray focus measurement and analysis method provided by the present invention can detect the focus position offset while measuring the focus size of the X-ray tube irradiating the target disk.

A method for determining the optimal position of the focal plane for examining a specimen by microscopy can include a) illuminating the specimen with light and recording images at different positions of the focal plane to provide a stack of intensity images, b) calculating a phase image from at least two intensity images, with the calculated phase image being assigned a focal plane position located within a focal plane region whose boundaries are the two most spaced apart positions of the focal plane of the at least two intensity images, c) repeating step b) multiple times with different intensity images such that a stack of phase images is available, d) calculating at least one focus measure value for each phase image, and e) determining the optimal position of the focal plane on the basis of the calculated focus measure values and the focal plane positions assigned to the phase images.

Proposed is a method for determining a focusing measure of a microscopic image, the microscopic image representing an image of a biological cellular substrate, the method comprising: providing the microscopic image, determining a gradient image on the basis of the microscopic image, processing image information from the gradient image and image information from the microscopic image by means of a neural network to determine the focusing measure, the focusing measure indicating quality of focusing in the microscopic image in relation to a cellular substrate plane of the cellular substrate.

Disclosed is a wedge arrangement comprising a plurality of wedge elements, arranged around an optical axis, the plurality of wedge elements comprising at least a first wedge element, a second wedge element and a third wedge element; wherein: said first wedge element comprises a first optical surface and second optical surface, wherein the first optical surface is planar and non-perpendicular to the optical axis and the second optical surface is non-planar such that said first wedge element has a non-linear thickness change; said second wedge element comprises a third optical surface and fourth optical surface which are each planar and are non-parallel; and said third wedge element comprises a fifth optical surface and sixth optical surface wherein the fifth optical surface is planar and non-perpendicular to the optical axis. Also disclosed is a metrology device which uses such a wedge arrangement in determining focus of measurement radiation during a measurement.

The present invention discloses a method and device for measuring an effective focus based on dynamic translation of a shielding plate, including: Step 1, collecting bright-field data; Step 2, adjusting the normal direction of the shielding plate to be parallel to the main direction of X-ray propagation, and the center of the shielding plate and the center of the X-ray source focus are located on the same horizontal line. Taking the side of the light-emitting window of the X-ray source as the starting point of movement, moving according to a preset step value until the shielding plate completely blocks the light-emitting window and stops moving. During the movement, use a detector to collect the photon energy distribution data after each movement of the shielding plate; Step 3, use the photon energy distribution data to inversely calculate the energy proportion of each sub-focus in the entire X-ray source focus, so as to obtain the size, shape and normalized intensity distribution of the X-ray source focus. The method of the present invention requires fewer additional devices and has high focus measurement accuracy. Higher spatial resolution images can be obtained using the focus information measured by this method.

The invention discloses a camera focusing, focus measuring and dispensing device which comprises a fixing frame, focus adjusting glue curing mechanisms, a lifting plate, a camera positioning mold, a lifting device and a belt conveyor, the focus adjusting glue curing mechanisms are mounted on the fixing frame, the lifting plate is connected to the lifting device, and the camera positioning mold is mounted on the lifting device. The plurality of camera positioning molds are mounted on the lifting plate and are used for positioning and lifting camera modules; the belt conveyor is arranged between the camera positioning molds and the focus adjusting glue curing mechanism and is used for conveying the camera modules; the equipment for focusing, focus measuring and glue dispensing of the camera is novel in structure, convenient to use and practical, focusing, glue dispensing and glue fixing are conducted on the camera through the focus adjusting glue curing mechanisms, meanwhile, the multiple focus adjusting glue curing mechanisms are arranged, the focusing of the camera is improved, the glue dispensing step is reduced, and the purpose of improving the production efficiency is achieved.

The first aspect of this disclosure is related to a computer-based method for measurement of a plurality of optical foci, comprising the steps: measuring a first focus; obtaining one or both of: a) a focus range for a measurement of a second focus, wherein the focus range is based on the first focus; b) a starting value for a measurement of a second focus, wherein the starting value is based on the first focus; measuring the second focus with the obtained focus range and / or staring value; discarding the second focus, if the second focus is measured as an extreme value of the focus range; measuring a third focus.

A focus measuring arrangement for ophthalmic examination comprises an infrared light source system, which directs infrared light to a pupil of an eye of a person and forms a focusing pattern of the infrared light on a retina. A receiving arrangement apertures receives the infrared light of the focusing pattern from the retina through separate areas of the pupil. An image forming arrangement causes the infrared light passed through the apertures to form an individual image of the focusing pattern for each of the apertures in an image space of the receiving arrangement, the image forming arrangement causing an optical correspondence between the at least two apertures and the separate areas of the pupil. A detecting surface arrangement is located at a non-zero distance behind the at least two apertures and the image forming arrangement in a direction of propagation of the infrared light reflected from the retina for receiving the infrared light passed through the at least two apertures. A data processing unit forms focusing adjustment information based on locations of illuminated spots of the infrared light of the focusing pattern on the detecting surface arrangement, and outputs the focusing adjustment information for further processing.

The invention proposes a method of determining a microscope image focus metric, the microscope image representing an image of a biological cell matrix, the method comprising providing a microscope image, determining a gradient image based on the microscope image, the image information of the gradient image and the image information of the microscope image are processed by a neural network for determining a focus measure, wherein the focus measure is indicative of a quality of focus in the microscope image relative to a cell matrix plane of the cell matrix.