207 results about "Small field of view" patented technology

An apparatus for imaging a structure of interest comprises a plurality of imaging detectors mounted on a gantry. Each of the plurality of imaging detectors has a field of view (FOV), is independently movable with respect to each other, and is positioned to image a structure of interest within a patient. A data acquisition system receives image data detected within the FOV of each of the plurality of imaging detectors.

A system and method for creating an image is presented. The system includes a first camera, a second camera, and a fusion processor. The first camera has a small field-of-view (FOV) and an optical line of sight (LOS). The second camera has a large FOV that is larger than the small FOV and the second camera has an optical LOS. The first camera and second camera are mounted so that the optical LOS of the first camera is parallel to the optical LOS of the second camera. The fusion processor fuses a second image captured by the second camera with a first image captured by the first camera. The fused image has better resolution in a fused portion of the fused image than in unfused portion of the fused image.

A camera with a pair of lens/sensor combinations, the two lenses having different focal lengths, so that the image from one of the combinations has a field of view approximately two to three times greater than the image from the other combination. As a user of the camera requests a given amount of zoom, the zoomed image provided will come from the lens/sensor combination having the field of view that is next larger than the requested field of view. Thus, if the requested field of view is less than the smaller field of view combination, the zoomed image will be created from the image captured by that combination, using cropping and interpolation if necessary. Similarly, if the requested field of view is greater than the smaller field of view combination, the zoomed image will be created from the image captured by the other combination, using cropping and interpolation if necessary.

An RFID-based tracking system that tracks persons and/or objects of interest without the need for triangulation techniques is disclosed. The system tracks persons and/or objects of interest by utilizing RFID antennas having a relatively small field of view and positioned relative to functional areas of a facility and/or within passageways between functional areas of the facility. The persons and/or objects of interest to be tracked are provided with an RFID tag. The present invention provides the system user with the ability to determine whether the persons and/or objects of interest are present within a particular functional area of the facility regardless of whether the presence of the person and/or object of interest is continuously detected by the system.

The invention discloses a spliced large area array digital aerial camera, which comprises a full color camera module and a multispectral camera module, wherein the full color camera module comprises a full color camera objective lens, a reflective pyramid beam splitting prism and four full color charge coupled devices (CCDs); and the multispectral camera module comprises four multispectral objective lenses and a CCD; the full color camera objective lens is positioned in the middle, and the four multispectral objective lenses and the CCD are symmetrically arranged at the periphery of the full color camera objective lens; the rear of the full color camera objective lens is provided with the reflective pyramid beam splitting prism; and the periphery of the reflective pyramid beam splitting prism is provided with the four full color CCDs. By the camera, the problem that a digital aerial camera has small breadth is solved, and a 20k*20k large-breadth high-resolution aerial image is provided; the camera comprises wide-angle, middle-angle and normal-angle full color camera objective lenses and multispectral objective lenses; and during work, the full color camera objective lenses at different angles can be flexibly selected according to different mapping applications, the angles of the multispectral objective lenses are matched with those of the full color camera objective lenses, and the problem that the conventional area array digital aerial camera has small field of view and single objective lens type is solved. Meanwhile, due to a mode of splicing a single full color objective lens and multiple full color CCDs, the image splicing difference caused by exposure difference of various full color cameras in the mode of splicing the multispectral objective lenses and the multiple CCDs is avoided.

A computed tomography scanner includes a first (20) and second (21) detectors. The second detector (21) has a relatively higher spatial resolution and a relatively smaller field of view (204) than that of the first detector (20). Projection data generated by the detectors (20, 21) is combined and reconstructed so as to generate relatively high resolution volumetric data (318) indicative of a region of interest (314) in an object under examination.

The invention relates to a wide field of view optical coherence tomographic instrument based on the adaptive optical technology, which comprises an optical source assembly, a reference arm assembly, an aberration detecting and correcting assembly, a two-dimensional imaging and scanning assembly, a wide field of view scanning assembly and a detector assembly. In the optical coherence tomographic instrument provided by the invention, an optical signal receiving part of a system mainly utilizes optical fibers and optical fiber couplers, so that the system has compact design. A lighting optical path part is designed by mainly using spherical reflector telescopes, so that the higher order aberration of the system is avoided. Meanwhile, the adaptive optical technology is introduced to detect and correct wave-front aberration, so that the light beam quality of the lighting optical path and an imaging optical path both achieve the level of diffraction limits. Through the synchronous operation of a fast tilting mirror and the two-dimensional imaging and scanning assembly, the high-resolution tomographic image of the human eye ground (or a sample to be measured) in a wide field of view range by using the automatic mosaic technology on the basis of the acquisition of a small field of view single-frame image. The invention mainly solves the difficulty of high-resolution and wide field of view synchronous imaging, the wide field of view optical coherence tomographic instrument with compact design and high imaging resolution and wide imaging field of view is realized, and the imaging field of view and the imaging quality of the traditional optical coherence tomographic instrument are greatly improved.

Minimally-invasive spinal inventions are often performed using fluoroscopic imaging methods, which can give a real-time impression of the location of a surgical instrument, at the expense of a small field of view. When operating on a spinal column, a small field of view can be a problem, because a medical professional is left with no reference vertebra in the fluoroscopy image, from which to identify a vertebra, which is the subject of the intervention. Identifying contiguous vertebrae is difficult because such contiguous vertebrae are similar in shape. However, characteristic features, which differentiate one vertebra from other vertebra, and which are visible in the fluoroscopic view, may be used to provide a reference.

The invention discloses a small-view-field magnetic resonance imaging method based on single-sweep super-speed orthogonal space-time coding. The method comprises the following steps of: enabling protons in a space to automatically rotate in an excitation phase by virtue of the organic combination of an orthogonally-distributed space coding gradient and a linear frequency sweep pulse to acquire a secondary phase related to a space position, thus carrying out two-dimensional space-time coding on the automatic rotation of the protons in an imaging plane; for the automatic rotation of the protons in an orthogonal space-time coding space, only the automatic rotation of the protons with static phase distribution can be detected during a decoding sampling period, and according to the characteristic of orthogonal space-time coding, decoding sampling can be carried out on a plurality of randomly-distributed areas in the space by designing a decoding sampling gradient, thus acquiring the magnetic resonance data of a plurality of areas of interest finally. High-resolution reconstruction is sequentially carried out on acquired magnetic resonance data of the plurality of areas, and then the high-resolution small-view-field magnetic resonance images of the plurality of areas can be obtained finally.

The invention discloses a small-sized optical system for an infrared medium wave detector, which comprises four lenses which are sequentially arranged from an object point to an image point along the same optical axis. Focal powers of the four lenses are positive, negative, positive and positive respectively, and a second lens is located at one of two positions which enable the object point and the image point to be conjugated; the object point performs imaging for the first time at a position of an intermediate image surface between a first lens and a third lens, and an image formed for the first time is subjected to further imaging on a photosensitive surface of the infrared medium wave detector through a fourth lens; and the focal distance of the optical system is set as fn in a working state of a small field of view, the diameter of the first lens is set as D1, the focal distance of the first lens is set as f1, the magnification of the fourth lens is set as m4, then the f1/fn is larger than or equal to 0.2 and smaller than or equal to 0.3, f1/D1 is larger than or equal to 0.7 and smaller than or equal to 1.2, and m4 is larger than or equal to -3 and smaller than or equal to -1.5. The small-sized optical system for the infrared medium wave detector has the advantages that miniaturization of infrared cameras is achieved, and simultaneously the optical system is guaranteed to have a large aperture, a long focal distance, double fields of view, and good imaging qualities.

The invention relates to the field of laser technology, and discloses a galvanometer scanning system for dual optical path imaging. The galvanometer scanning system comprises a first lens, a second lens, a large field of view imaging unit, a small field of view imaging unit, a focusing mirror, an XY scanning galvanometer, and an optical source. An external laser optical path reaches the XY scanning galvanometer through the first lens, and after reflection, acts on an object to be marked to conduct marking sequentially through the focusing mirror and the second lens. The optical source is lit up to send out a lighting optical path to illuminate the object to be marked, the lighting optical path is reflected onto the second lens, a part of the lighting optical path is reflected through the second lens into the large field of view imaging unit to image for monitoring the marking condition. The other part of the lighting optical path is focused through the second lens and the focusing mirror onto the XY scanning galvanometer, and reflected through the first lens into the small field of view imaging unit to image for detecting the marking condition. The invention can improve the detection accuracy and detection efficiency of the scanning system.

A method and system are presented for automatic target finding by using two imaging channels with relatively low and high magnifications, using the low magnification channel (relatively large field of view) for finding a region of interest (i.e., that of the targets location within the field), scanning this zone by grabbing images via the high magnification channel (relatively small field of view) and marking the overlay targets using image processing algorithms.

A method and apparatus for displaying composite images, as viewed from a relatively stationary eye point, including a moving target image of relatively small field-of-view overlaid on a background image of relatively large field-of-view, by generating a background image video stream of image data for the background image; updating the background image video stream at a zero or low data update-rate; generating a target image video stream of image data for the target image; updating the target image video stream at a relatively high data update-rate; combining the background and target image video streams to produce a combined video stream; and feeding the combined video stream to a display system for displaying the composite images. The described preferred embodiment is a simulator, wherein the display system includes a plurality of projectors each projecting a predetermined section of the composite image including the background of the respective section, and the portion of the target in the respective section.

The invention discloses a large-view-field wavefront detection method based on a focal plane Hartmann wavefront sensor, and the method comprises the steps: recording the spatial information through alight spot array image detected by a CCD detector in the focal plane Hartmann wavefront sensor, and recording the phase information through a microlens array, i.e., incident light waves of different view fields or angles. Based on the special optical structure, wavefront information of multiple fields of view can be measured at a time, and therefore the effect of a large field of view is achieved.However, a traditional wavefront detector generally has a small field of view or a zero-degree field of view and can only detect a middle field of view. According to the invention, the problem of wavefront error large-view-field measurement is solved, and under the condition that the detection caliber of the wavefront detector is fixed, the view field range of wavefront information which can be restored by single exposure is increased, and the image restoration precision is enhanced.

The invention discloses a method for optimizing a freeform surface optical system in combination with a surface form and a field-of-view optimization strategy. The method uses the respective coefficients of a Zernike standard polynomial representing an optical system wave aberration as an evaluation basis, develops a optimization process by a successive approximation strategy combining surface form optimization and field of view optimization, and comprises steps of: firstly, selecting an initial small field of view, searching out the maximum item of system aberration targetedly in each optimization step according to an established XY polynomial and a polynomial relation model, selecting a corresponding XY polynomial item in the freeform surface as a new-added variable to optimize and balance the aberration, and synchronously adjusting the weight of each field of view according to the wave aberration rms values of respective fields of view of the system; after a structure satisfying a performance index is optimized and acquired within a small field of view range, gradually expanding the field of view and repeating the optimization steps until optical system structure parameters within all field of view range are obtained. The method has a large field of view, fast optimization speed, aberration pertinence and guidance.

The invention discloses a double-field thermal imager, comprising a thermal imaging lens, an infrared detector, a signal processing and control circuit and a servo motor control system, wherein the signal processing and control circuit is composed of an FPGA (Field Programmable Gate Array) controller circuit, an image processing circuit and a power circuit; the servo motor control system is composed of a focal length positioning controller, a servo motor, a motor drive circuit and a coder, and accomplishes the switching and focusing functions of large and small fields of view. The invention further discloses an automatic focusing method, wherein the definition of an image is reflected by a focusing evaluation function value, and the focusing search direction is determined by three points, so that the reliability of the automatic focusing effect is ensured; meanwhile, the search step length is adjusted in time according to the focusing evaluation function difference of two adjacent points, so that the focusing efficiency is improved.