V.V. Shapovalov, B.S. Gurevich, S.V. Andreyev, A.V. Belyaev, I.A. Kolesov

All analytical instruments including the devices providing analysis of biological objects, deal with the processes of information processing and transmission. It follows that while elaborating these instruments, for example, imaging spectrophotometers, it is necessary to analyze the processes of information transmission and to find the sources of information losses. \in order to provide this, it is appropriate to use the methods of information theory modified for the certain kind of the device. For example, for the devices where information transmission partially is performed in optical form, it is useful to use the methods of information optoelectronics. One of the most efficient methods of the information transmission analysis is connected with the division of the system which transmits this information, into several consequent links, in each of which the certain physical process performs the signal transformation. Analyzing the device by such way, it is useful to consider the information structure of the imaging spectrophotometer and its separate units. First of all, it is related to the most important unit of the device playing a decisive part in information processing and transmission - acousto-optic tunable filter (AOTF) which allows to perform the programmable selection of the separate spectral line in a given consequence. The imaging spectrophotometer includes the special kind of this device - AOTF with wide angular aperture which provides transmission not only spectral information but also spatial one. The links performing transformation of the service and signal information in AOTF, are considered, the transmission factors of these links are estimated, and the noise sources are analyzed. An experimental measurement method of the noise appeared in a Bragg cell which represents the basis of AOTF, is proposed and analyzed. The AOTF noise influence on information abilities of the imaging spectrophotometer is also considered.