The hybrid model for analyzing distortions of a laser beam passed through moderately scattering medium with the number events up to 10 is developed and investigated. implemented Monte Carlo technique simulate propagation layer, ray-tracing propagate scattered measurements plane, Shack–Hartmann calculate distortions. results obtained from were confirmed during laboratory experiment. Both numerical experiment showed that an increase concentration value particles in range 105 106 mm−3,...

The bimorph deformable mirror with a diameter of 320 mm, including 127 control electrodes, has been developed and tested. flatness the initial surface about 1 μm (P-V) was achieved by mechanically adjusting substrate fixed in metal mount. To correct for aberrations improve beam focusing petawatt Ti:Sa laser, wide-aperture adaptive optical system Shack–Hartmann wavefront sensor developed. Correction 4.2 PW laser using provided increases intensity plane to value 1.1 × 1023 W/cm2

Problems of constructing an adaptive optical system intended for correcting the wavefront laser radiation that has passed through a turbulent atmosphere are considered. To ensure high-quality correction, frequency discrete should be at least 1 kHz or more. This performance can achieved by using FPGA as main control element system. The results laboratory experiments beam phase fluctuations caused turbulence, produced airflow fan heater, correction means FPGA-based presented. efficiency was...

Abstract This paper reports a large-aperture adaptive optical system with bimorph deformable mirror and Shack – Hartmann wavefront sensor for aberration correction beam focusing improvement in state-of-the-art petawatt Ti : sapphire lasers. We consider methods providing feedback to the obtaining an objective that optimises onto target. The use of controlled 127-channel 320-mm-aperture laser output power 4.2 PW has made it possible obtain record high intensity: 1.1 × 10 23 W cm −2 .

The rarely considered case of laser beam propagation and focusaing through the moderately scattering medium was researched. A phase-only spatial light modulator (SLM) with 1920×1080 pixel resolution used to increase efficiency focusing radiation propagated 5 mm layer suspension 1 µm polystyrene microbeads in distilled water concentration values ranging from 105 106 mm−3. CCD camera micro-objective estimate intensity distribution far-field focal spot. Shack-Hartmann sensor measure wavefront...

The rarely considered case when the optical radiation passes through weakly scattering medium, e.g. mid-density atmospheric fog with number of events up to 10 was investigated in this paper. We demonstrated an improvement focusing a laser beam (λ=0.65 µm) passed 5 mm-thick layer suspension 1 µm polystyrene microbeads diluted distilled water. For first time low-order aberration corrector – wide aperture bimorph deformable mirror 48 electrodes configured 6 rings used optimize far-field focal...

This paper presents a FPGA-based closed-loop adaptive optical system with bimorph deformable mirror for correction of the phase perturbation caused by artificial turbulence. The system’s operating frequency about 2000 Hz is, in many cases, sufficient to provide real-time mode. results wavefront laser radiation distorted airflow formed laboratory conditions help fan heater are presented. For detailed consideration, expansion Zernike polynomials is used further statistical analysis based on...

In this paper we consider two approaches widely used in testing of wide aperture optics: Fizeau interferometer and Shack-Hartmann wavefront sensor. that is common instrument optical can be transformed to a device using sensor, the alternative technique check components. We call Hartmannometer, compare its features those interferometer.

In this paper we consider two approaches widely used in optical testing: Shack-Hartmann wavefront sensor and Fizeau interferometer technique. that is testing can be easily transformed to a device using sensor, the alternative technique check components. We call Hartmannometer, compare its features those of interferometer.

The results of a study the wavefront distortions laser radiation caused by artificial turbulence obtained in laboratory conditions using fan heater are presented. Decomposition terms Zernike polynomials is standard procedure that traditionally used to investigate set existing aberrations. In addition, spectral analysis dynamics makes it possible estimate fraction energy distributed between different modes. It shown related low-order higher compared high-order polynomials. Also, one...

Conventional Shack-Hartmann sensor uses Zernike polynomials in order to approximate the wavefront of light. approximation is well-known, well-established and widely used technique. And most cases quality good enough, especially if measured light beam has circular aperture. But when rectangular or ringshaped (for example, one need measure surface flatness detail that ring-shaped), using fails. In this work we implemented approach Bspline polynomials. We present results a complex simulated...

Distortions of the scattered laser beam (λ=0.65μm) were numerically estimated by means Shack-Hartmann technique and experimentally measured. The ability to focus beam, passed through scattering suspension polystyrene microspheres in distilled water, using bimorph deformable mirror was investigated both experimentally. used measure local slopes Poynting vector, CCD camera analyze intensity distribution focal spot far-field. Bimorph with 14 electrodes utilized order increase focusing...

The latest results on intensity distribution transformation from Gaussian to a flattop and doughnut are presented in the paper. wavefront was modified with bimorph deformable mirror reach desired farfield. LC phase modulator also considered as an alternative device for laser beam shaping. theoretical calculations experimental of efficiency different types correctors given.

The ability to focus laser beam with wavelength 0.65 um through the multiply scattering suspension of polystyrene microspheres, diluted in distilled water, was investigated. Experimental setup, contained Shack-Hartmann sensor for measurements local slopes Poynting vector, CCD camera estimation far-field focal spot's intensity and bimorph mirror 48 electrodes built. Numerical experimental investigations focusing efficiency carried out also.

Abstract An adaptive optical system is developed to correct the wavefront of laser radiation distorted by a turbulent air flow. The use field-programmable gate array as main control element makes it possible achieve bandwidth 2 kHz. results experiments on dynamic correction phase beam flow heated are presented and analysed.

Bimorph deformable mirror with 63 electrodes on 20 mm aperture is discussed. Methods of dividing all round electrode into sectors a square 2-4 mm2 are described. Results flat-top beam formation by means 50 bimorph 48 and miniature 27 presented.

A combined adaptive optical system designed to correct the wavefront of light radiation distorted by influence strong atmospheric turbulence is presented. The consists a beam position stabilizer and fast operating in real time. Stabilization carried out two electronically controlled tilt mirrors. control loop includes quadrant sensors an FPGA (field-programmable gate array) that closes feedback loop. Using information received from Shack-Hartmann sensor, bimorph-based mirror, another FPGA,...

We investigate the ability to focus laser beam (&lambda;=0.65<i>&mu;m</i>) propagated through scattering suspension of polystyrene microspheres in distilled water by means bimorph deformable mirror. Shack-Hartmann sensor was used measure local slopes Poynting vector, while CCD camera intensity focal spot farfield. Bimorph mirror with 14 electrodes applied order increase far-field. investigated efficiency focusing improvement three techniques: LSQ fiterror minimization sensor, Hill-climbing...

A high-quality flat wave front is usually used to calibrate the Shach-Hartmann wave-front sensors. The article discusses possibility of calibrating sensors with spherical fronts. Special attention paid consideration calibration in standard laboratory conditions. mathematical apparatus and scheme experiment are considered.

Abstract We report the results of analysis experiments on dynamic phase correction laser radiation distorted by a turbulent airflow in an adaptive optical system (AOS) with Shack–Hartmann wavefront sensor (WFS). A field-programmable gate array is used as main AOS control element, which provides closed loop bandwidth up to 2000 Hz. The WFS estimate characteristic generated turbulence ν turb . Changes spatial and temporal spectra phase, well quality beam during its at various frequencies, are...

Laser beam propagation through the scattering suspension of polystyrene microspheres in distilled water was studied. The distorted laser analyzed by both Shack-Hartmann sensor and CCD camera. measured local slopes Poynting vector were compensated for means bimorph deformable mirror with 14 electrodes order to increase intensity focal spot far-field. Three different techniques focusing implemented compared: LSQ fit-error minimization sensor, Hill-climbing optimization far-field

Laser beam focusing (&lambda; = 0.65 &mu;m) through the scattering suspension of polystyrene microspheres in distilled water was investigated. Shack-Hartmann sensor used to measure local slopes Poynting vector, CCD camera far-field focal spot’s intensity. Numerical and experimental investigations efficiency two bimorph deformable mirrors with 14 48 control channels were performed.

In this paper we consider two approaches widely used in testing of spherical optical surfaces: Fizeau interferometer and Shack-Hartmann wavefront sensor. that is can be transformed to a device using sensor, the alternative technique check components. We call Hartmannometer, compare its features those interferometer.

We present an adaptive optical system to stabilize the position of a laser beam passed through turbulent atmosphere. The uses two tip-tilt mirrors and is controlled by FPGA increase bandwidth. An internal structure presented. reads error signal from sensors formed quadrant photodiodes calculates voltages be applied piezo-driven control units.