The invention relates to a method for determining measurement parameters 7, 8, 9, 12, 14, 15, 18, 19 of a spectacle wearer from an image of the spectacle wearer provided with a spectacle frame, wherein it is determined on the image, automatically, the position of the center of each pupil by analyzing a luminance gradient in the region of each pupil, and wherein it is determined on the image, so Automatic, the positions of horizontal and vertical lines tangential to the frame, by luminance gradient analysis and extraction of the contours of the frame. The invention eliminates the need to manually acquire the image the position of various elements sought.

An optical metrology.

Methods for correcting aberrations of images, obtained by an optoelectronic camera with the use of preliminary measured calibration function, provoke wide interest in recent years. For the most part these methods are not characterized by high accuracy and are typically used for cameras with objectives having rather high relative distortion. In this article the method is discussed for measuring distortion of a wide-angle objective for calibration of photoelectric cameras designed to measure angular coordinates of remote objects with the accuracy as high as 10 arcseconds. It is proposed to use an air mirror-wedge as a test object, which allows creating a sheaf of collimated beams. The calibration function of a photoelectric camera is calculated by mathematical post-processing of the recorded frames. The proposed method was experimentally tested for photoelectric cameras with full angular fi elds-of-view of 21 degrees and angular pixel sizes of 20 arcseconds. The subpixel accuracy of determining the calibration function is demonstrated.

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Method for measuring distortion in wide-angle video channels

Image forming lens systemsdo not provide perfect images Lens abberations can be detected with complex optical ray-tracing A single aberration in lenses, the distortion, can be detected at the image plane with optical mapping Therefore moire interferometry can be adapted to detect and measure distortion This method is adaptable by serial testing of the universal measuring cameras, projection cameras, photogrammetrical cameras, etc The distortion of the whole image plane can be represented on one moire image This can be useful if the distortion is not rotationally symmetrical for example because of errors of assembly The distortion of 1 µm regarding the focal plane can be measured by using the moire method presented in this paper

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P. Tamas

Papers

Measurement of Distortion Using the Moire Interferometry