65 results about "Vignetting" patented technology

A combination of a scanning laser ophthalmoscope and external laser sources (52) is used for microphotocoagulation and photodynamic therapy, two examples of selective therapeutic laser. A linkage device incorporating a beamsplitter (56) and collimator-telescope (60) is adjusted to align the pivot point (16) of the scanning lasers (38, 40) and external laser source (52). A similar pivot point minimizes wavefront aberrations, enables precise focusing and registration of the therapeutic laser beam (52) on the retina without the risk of vignetting. One confocal detection pathway of the scanning laser ophthalmoscope images the retina. A second and synchronized detection pathway with a different barrier filter (48) is needed to draw the position and extent of the therapeutic laser spot on the retinal image, as an overlay (64). Advanced spatial modulation increases the selectivity of the therapeutic laser. In microphotocoagulation, an adaptive optics lens (318) is attached to the scanning laser ophthalmoscope, in proximity of the eye. It corrects the higher order optical aberrations of the eye optics, resulting in smaller and better focused applications. In photodynamic therapy, a spatial modulator (420) is placed within the collimator-telescope (60) of the therapeutic laser beam (52), customizing its shape as needed. A similar effect can be obtained by modulating a scanning laser source (38) of appropriate wavelength for photodynamic therapy.

A multiscale telescopic imaging system is disclosed. The system includes an objective lens, having a wide field of view, which forms an intermediate image of a scene at a substantially spherical image surface. A plurality of microcameras in a microcamera array relay image portions of the intermediate image onto their respective focal-plane arrays, while simultaneously correcting at least one localized aberration in their respective image portions. The microcameras in the microcamera array are arranged such that the fields of view of adjacent microcameras overlap enabling field points of the intermediate image to be relayed by multiple microcameras. The microcamera array and objective lens are arranged such that light from the scene can reach the objective lens while mitigating deleterious effects such as obscuration and vignetting.

A method used for the compensation of vignetting in digital cameras has been achieved. The compensation for vignetting is performed by multiplying pixel output of the sensor array with a correction factor. In a preferred embodiment of the invention all pixels are multiplied with an adequate correction factor. Alternatively pixels, being close to the center of the sensor array, can be left unchanged. Said correction factor can be calculated in a very fast and efficient way by using two constant factors describing the specific geometry of the lens/sensor array system and by multiplying a first of said factors with the square of the distance between a pixel and the center of the sensor array and by multiplying a second of said factors with the distance between a pixel and the center of the sensor array to the power of four. The result of the second multiplication is subtracted from the result of the first multiplication and this result is added to one to get the final correction factor. Each original pixel output is multiplied with said correction factor to get output data compensated for the vignetting effects of the lens.

A solid state image sensor includes an array of pixels and a corresponding array of microlenses. The positions of the microlenses relative to their corresponding pixels may vary according to the distances of the pixels from a central optical axis of the image sensor to substantially eliminate vignetting of light collected by the microlenses.

An apparatus and method is provided for excluding vignetting occurring during wide-angle shooting using a camera. When a focal length of the camera is computed and an ISO range is set using a result of measuring an amount of light, a view angle wider than the inherent view angle of a camera module can be provided. Therefore, vignetting can be removed and an image of an area wider than the current capture range can be captured.

A plenoptic camera device and a shading correction method thereof are provided. The plenoptic camera device includes a processor including a shading correction block configured to determine a four-dimensional axis with respect in a raw image, generate a four-dimensional profile by applying a polynomial fit with respect to the plurality of pixels in the raw image based on the four-dimensional axis, and calculate a gain using the four-dimensional profile and a non-volatile memory device configured to store the gain. Accordingly, the plenoptic camera device can remove a vignetting effect using the gain.

To provide the technology of an image-pickup device that can easily determine whether or not an image is photographed by mounting an interchangeable lens designed for an image-pickup device of an exposure-surface size different from an image-pickup element provided in a camera body. In an image-pickup system, when shooting is performed by mounting an interchangeable lens ready for an image-pickup surface of a size smaller than an image-pickup surface of an image-pickup element installed in the camera body (camera-main body), the main image (high-resolution record image) corresponding to a partial region at the center of the image-pickup surface, the partial region being free of vignetting caused by an insufficient circle, is generated, and a reduced image (e.g, a thumbnail image) is generated by reducing a whole image obtained on the entire image-pickup surface (steps ST10 and ST12). Subsequently, the vignetting can be visually identified in an image photographed in the state where an inappropriate interchangeable lens is mounted when the reduced image is displayed (when the image reproduction is performed) so that it becomes possible to easily determine that the image is photographed by mounting the inappropriate interchangeable lens.

An image capturing apparatus includes: a focus detection unit configured to perform focus detection based on a phase difference between a plurality of image signals obtained by photo-electrically converting light beams that respectively pass through different partial pupil regions of an imaging optical system; an image blur correction unit configured to correct image blur of an object image by driving an optical member for image blur correction; and a determination unit configured to determine reliability of a focus detection result detected by the focus detection unit based on information regarding a focus detection area with respect to which the focus detection unit performs focus detection, and information regarding vignetting that occurs in light beams that pass through the imaging optical system as a result of the image blur correction unit correcting the image blur.

The invention relates to the field of large-field-of-view and high-resolution imaging technology, in particular to a bionic optical imaging system. The imaging system comprises at least two subsystems, each subsystem comprises a concentric spherical objective lens and at least two sub-aperture cameras, and the optical axis of each sub-aperture camera of each subsystem passes through the center ofthe concentric spherical objective lens of the corresponding subsystem. Field angles are set at intervals for images captured by the sub-aperture cameras, and the vacant parts of the field angles setat intervals are complemented by image overlapping of the subsystems and are continuous within the set field of view, so that the adjacent sub-aperture cameras are spaced a certain angle, the interference between the sub-apertures is effectively prevented, vignetting of the imaging system is reduced, the imaging system has good illumination uniformity in the field of view, and the problems of lowimaging quality, difficult stitching and the like caused by structural interference and vignetting of the edge field of view of the acquired image in the existing large-field-of-view and high-resolution optical imaging system are solved.

The invention relates to a method for measuring the damage of a shear wall based on a digital image, and the method comprises the following steps: setting a camera for collecting the image of the shear wall, and calibrating the response and vignetting of the camera based on the response function and vignetting function of the camera; obtaining a DIC digital image correlation model used for calculating a correlation function of position change of any point from a reference image of a previous frame to a current image of a next frame and pixel change of a target point based on illumination influence; collecting a video of the shear wall through a camera for photometric calibration, obtaining a front frame image and a rear frame image from the video, setting the size of an image capture window, capturing pixel change and position change of a global target point of the shear wall through a DIC digital image correlation model and a correlation function of target point pixel change based on illumination influence, and calculating the strain change of the global target point according to the pixel change and the position change of the global target point; and generating a real-time damage identifier of the shear wall according to the strain change of the global target point.