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In the operation schemes of optical electronic devices (OED), such as digital autocollimators, direction finders, Shack-Hartmann sensors, as well as astro-orientation systems, projection measuring systems, geometric calibration schemes for OED, the photo-detector acts not only as a receiving device, but also as a measuring device. The tasks facing the OED photo-detectors. The solution to the problem is the use of several photo-detectors installed on one electronic board. Since OED photo-detectors act, inter alia, as measuring devices, it is necessary to perform their geometric calibration. Geometric calibration involves the measurement of interior orientation parameters used in the processing of OED images. Geometric calibration makes it possible to eliminate errors in mutual exposure of photo-detectors on one electronic board installed in the focal plane, as well as distortions introduced by the OED lens, primarily by distortion. The correctness of the interior orientation parameter determination is influenced by the relative position of the collimator, with the help of which the geometric calibration is performed, and the calibrated OED itself, i. e. the external orientation elements. The task is to separate the interior orientation parameters and the elements of external orientation. This is achieved using the method of mathematical processing of measured data in the forward and inverted positions of the collimator. This method of geometric calibration allows to use it for geometric calibration of OED with a large number of photo-detectors. The paper presents the results of the geometric calibration of the interior orientation parameters when the collimator projects a test object onto three photo-detectors of the OED layout. The factors influencing on the accuracy of the geometric calibration of the interior orientation elements for OED are determined in the paper. The developed method for geometric calibration of the interior orientation parameters for multi-matrix OED provides high measurement accuracy – not more than 0.1''–0.2''.

A digital micromirror device (DMD) micromirrors periodic spatial structure is a measuring scale in interior orientation parameters calibration of optoelectronic devices problems, when using a DMD as a testobject. It is important that DMD micromirrors periodic spatial structure remains constant. Change in a DMD micromirrors spatial structure may occur due to heating. In addition to heating a DMD, an optoelectronic device photodetector is also subject to heating and, accordingly, change in its spatial structure. It is necessary to estimate change in a spatial structure of DMD micromirrors and an optoelectronic device photodetector.A DMD micromirrors spatial drift and a DMD micromirrors spatial drift together with a digital camera photodetector pixels spatial drift for operation 4 h are analyzed. The drift analysis consisted in the points array position assessing formed by a DMD and projected onto a digital camera. When analyzing only a DMD micromirrors drift, a digital camera was turned on only for shooting time for exclude digital camera influence. A digital camera did not have time to significantly heat up, during this time. After a digital camera it cooled to a room temperature.Average drift of all DMD micromirrors determines the accuracy of interior orientation parameters calibration of optoelectronic devices using a DMD in time. Maximum drift of all micromirrors after switching on is observed. Minimum DMD warm-up time is 60 min for average drift of all micromirrors less than 1 μm is necessary. Minimum DMD warm-up time is 120 min when using a DMD together with a digital camera is necessary.A DMD expansion uniformity determines the accuracy of interior orientation parameters calibration of optoelectronic devices using a DMD, because irregular expansion disturbs micromirrors periodicity. The average change in distance of neighboring points is less than 0.1 μm for every 20 min.Thus, a DMD can be used as a test-object in interior orientation parameters calibration of optoelectronic devices. The results can be used as compensation coefficients of change in DMD micromirrors spatial structure due to temperature effects during operation, if more accurate are necessary.

The paper considers a control scheme of such optoelectronic devices with matrix photo-detectors as autocollimators, microscopes, star trackers and other film equipment an d the control is carried out with the help of a collimator. A number of factors (structure discreteness, photo-detector noise, consistency in collimator test-object size, photo-detector pixel size and point scattering function of optical components) exert an influence on control accuracy.In the context of control problems and alignment of optoelectronic devices the paper studies a scheme which includes two components: controlling component that is a collimator and a component to be controlled that is a tele-centric system). A mathematical model for control schemes has been proposed with the purpose to determine an effect of the above-mentioned factors and its mathematical implementation has been described in the paper.Due to simulation an optimal ratio has been selected for component parameters of the optical control scheme: point scattering function for a collimator objective and a telecentric system, collimator test-object size, photo-detector pixel size. A collimator test-object size has been determined in the paper. Using the considered scheme the size will give the smallest measurement error caused by photo-detector discreteness of a controlled device. A standard deviation of the gravity energy center for a collimator test-object caused by photo-detector noise has been determined in the paper. In order to reduce the effect of photo-detector noise the paper proposes to take as zero values of a signal such values which are smaller than a doubled discretization interval of an analog-to-digital converter.

Proposed structure and layout of the target and on-board equipment microsatellite for remote sensing of the Earth, taking into account its impact on the main disturbing factors occurring in the derivation and operation of spacecraft in orbit. Recommendations on the choice of optimal design of micro power skeleton, based on modeling the impact on his body external loads.