Дослідження похибок суміщення стереопари растрів

Abstract

Проаналізовано похибки суміщення стереопари растрів, які виникають за рахунок геометричних та нелінійних спотворень окремих растрів. Розглянуто сумарну похибку місцеположення елементів суміщених растрів за рахунок цих спотворень. Stereo television scanning optical microscope (STSOM) – is a microscope, its operating principle is based on using as the light source cathode ray tubes (CRT). Using STSOM which provide three-dimensional perception of the image investigated object (IO), significantly expands descriptiveness and as a result speed and quality of conducting research. For forming the stereoscopic image in STSOM is used stereo pair united in the plane of IO two rasters. There are following variants of forming stereo pair of rasters: with two CRT and with one CRT. The two rasters are combined in the plane of IO by using: lens which axis are located parallel or at an angle and lens which axis are parallel and are shifted relative to the center. The choice of a variant depends on the geometric distortion of stereo pair of rasters which affect on precision of forming stereoscopic image of IO. At combining of stereo pair arise a distortion which make obstacle in perception of stereo effect and might lead to his loss. One of the important parameters of any stereo system is its number of plans by depth which is determined by distance between two points of rasters for the left and right eye which can be distinguish. Minimal relative error of any element location of first scanning raster in relation to the corresponding element of the second scanning raster of stereo pair of rasters depends on the number of plans by depth and. Total error of location determined by errors at the expense of geometrical distortions of rasters, nonlinear distortions of rasters, unequal dimensions of scanning rasters, offset of a one rasters of stereo pair with regard to the second raster and rotation one rasters of stereo pair with regard to the second raster. Analysis of errors that arise by combining two rasters was conducted. By combining two rasters centers of rasters are combined and errors their respective points are added. By combining two rasters with identical distortions horizontal error or vertical error will remain such for one raster, as combined raster elements will be shifted by the same amount, stereo effect will be not lost. The biggest error will be at the combining rasters with distortion “barrel” in one raster and distortion “pillow” in the second raster. The total error of geometrical distortion at every point of scanning rasters will be determined by the square root of the sum of squared errors horizontally and vertically. By using two CRTs total error will be the biggest at the edges of the raster and will fall to zero as it approaches to the center of the raster. By using one CRT total error of geometrical distortion is biggest with the combining rasters with distortions such as: trapeze – trapeze, trapeze – parallelogram and parallelogram – parallelogram. The analysis of errors by nonlinear distortions of raster were conducted. The biggest error is the combination of one edge of rasters. The smallest nonlinearity error is the combining in the deflection zone which corresponds to the time 0,6 line period.