Alexey Leshchev

Dynamic correction for distortions in imaging optical systems using liquid crystal SLMs

Given are the results of experimental study on the quasi real time holographic correction for the lens distortions in the passive observational telescope in the visible range of spectrum, using the liquid crystal optically addressed spatial light modulator.

Experimental realization of the laser telescope with overall compensation for distortions via phase conjugation

For the first time was realized the laser telescope (beam director), in which the phase conjugation provides the comprensation for the distortions, caused by the primary and secondary mirrors. Nearly diffraction limited laser beam divergence was realized under the significant disadjustments and disalignments of the segmented mirror.

Two-wavelength dynamic holography

Two-wavelength holography, when the hologram is recorded at one wavelength and reconstructed at some shifted wavelength, is an efficient tool for many applications. Optically addressed liquid crystal spatial light modulators are very convenient for recording thin dynamic holograms and, in particular, for the purposes of the dynamic two-wavelength holography. On such a basis one can realize the dynamic interferometer, providing the arbitrary scaling of the wave front distortions. Such an interferometer can be of use for solution of some of the tasks of the adaptive optics, namely, for simplification of the procedure of measuring of the robust wavefront distortions, for recording of the dynamic holographic correctors, working in spectral ranges, where the direct holographic record is impossible, in particular, in mid-IR range of spectrum, and for extension of the range of distortions, which can be corrected by means of the phase valve, mounted in the negative optical feedback loop. We report the experimental realization of such an interferometer.

Theoretical optimization of power performance of the master oscillator-power amplifier system using cw HF chemical lasers and laser beam-director telescope with nonlinear optical compensation for distortion

The results of performance theoretical optimization of laser system consisting of a cw chemical HF laser Master Oscillator- Power Amplifier (MOPA) configuration, of a beam-director telescope and of a phase conjugate mirror are presented. The following optimal physical parameters have been found: required active medium length of Power Amplifier, required master oscillator output power, optimal relation between diffraction coefficients of splitting on the diffraction optical element onto the surface of the secondary mirror of laser beam-director telescope to the zero and first orders, required level of the threshold power to ensure phase conjugation by stimulated Brillouin scattering.

White-light imaging using large-numerical-aperture telescope with dynamic holographic correction for primary mirror distortions

Large numerical aperture telescope with nonlinear optical correction for distortions, designed for the remote self- luminous object imaging, was realized in experiment and investigated. Dynamic hologram, recorded in optically addressed liquid crystal spatial light modulator, was used as the corrector. Nearly diffraction limited performance of the system was demonstrated.

Experimental realization of a laser telescope with overall compensation for distortions via phase conjugation

For the first time was realized the laser telescope (beam director), in which the phase conjugation provides the compensation for the distortions, caused by the primary and secondary mirrors. Nearly diffraction limited laser beam divergence was realized under the significant disadjustments and disalignments of the segmented mirror.

NONRECIPROCAL OPTICAL SYSTEMS WITH PHASE-CONJUGATING MIRRORS — A NEW CLASS OF OPTICAL IMAGING SYSTEM

A method for removing some of the restrictions imposed in conventional phase conjugation imaging applications is proposed. It provides the possibility of transformation of both the image scale and its distance from the imaging lens system. Theoretical treatments and numerical results for the paraxial as well as the nonparaxial cases are presented, along with experimental demonstrations of the feasibility of this method.

Large numerical aperture imaging bypass system with dynamic holographic correction for primary mirror distortions

Large numerical aperture telescope with nonlinear optical correction for distortions, designed for the remote self- luminous object imaging, was realized in experiment and investigated. Dynamic hologram, recorded in optically addressed liquid crystal spatial light modulator, was used as the corrector. Nearly diffraction limited performance of the system was demonstrated.

Polychrome correction for telescope lens distortions using a liquid crystal optically addressed spatial light modulator

Given are the results of experimental study on the quasi real time holographic correction for the lens distortions in the passive observational telescope in the visible range of spectrum, using the liquid crystal optically addressed spatial light modulator.

Large-size laser collimator with phase conjugation compensation for primary mirror distortions

The novel scheme of laser collimator for optics testing and evaluation purposes is proposed, using the principles of the bypass telescopes with the nonlinear-optical compensation for the primary mirror distortions.