DEVELOPMENT OF AN OPTICAL SYSTEM WITH DISCRET CHANGE OF FOCAL LENGTH
Siberian State Academy of Geodesy, Department of Optical Devices; Post-Graduate Student
T. N. Hatsevich
Siberian State Academy of Geodesy, Department of Optical Devices;
Abstract. Development of high-aperture lens with the possibility to change discretely its focal length is a challenge for designer of IR apparatus. A parametric model is proposed for thin-component lens with discrete variation of focal length, minimal number of moving elements, and fixed system length and rear aperture angle. With the use of the model, fast lenses with discretely variable focal length in the range of 8—12 mm was developed. Evaluation of image quality is based on comparison of real lens MTF with diffraction-limited MTF of an ideal lens.
Keywords: discrete change of focal length, fast thermo-vision camera lens, spectral range from 8 to 12 μm.