As other acousto-optic devices, acoustooptic tunable filters (AOTF) deal with information processing and transmission. However, in major cases, AOTF transmits information in a specific form -the data are containrd in output light spectrum or wavelength. The estimation of possible amount of information which can be processed and transmitted by AOTF, requires to define the resolving power of a device by wavelength. The wavelength resolving power criterion has been elaborated in the presented paper. It proceeds from the condition of the necessary probability of one bit of information recognition. Taking into consideration this criterion as well as the need to distinguish gray scales in a pattern of wavelengths, the information transmission capability of AOTF has been calculated. Along with that, it has been shown that such parameter as information capacity of AOTF represents a significant importance while analyzing the spectral composition of light transmiued through media to be studied. Some features of tellurium dioxide single crystals influencing the AOTF information possibilities, have been discussed.