The satellite remote sensing instruments for climatic studies are required to have: (1) fast time sampling, (2) high spectral resolution, (3) high space resolution, (4) wide field of view, (5) broad spectral range, (6) simultaneous measurements in different spectral intervals and/or type of measurements (7) lack of movable mechanical parts, etc. Here it is described the main idea of an input optic of remote sensing UV-VIS-IR instrument aimed for climatic studies form the space. It is attempted with the proposed optical system to satisfy requirements (2), (6), (5), (7) and, at least partially, the rest ones.