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A novel algorithm of compensation for repetitively-pulsed laser beam wandering at propagation paths, caused by the atmospheric turbulence and mirror vibrations has been proposed and verified in experiments with a TE-C02 laser. The algorithm is based on the precise temporal control of triggering each of the TB-laser pulses at the moments when the auxiliary probe cw-laser beam modified by a modal-type adaptive optics system and having exactly the same wavefront profile, as the pulsed radiation, hits the remote object (retroreflector in the pre-set point at the path exit) by its brightest speckle.

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Laser micromachining is a powerful technique that is commonly used in microfabrication. Typically such laser systems are computer controlled, and the required microstructure is fabricated by multiple machining iterations, where the control program is modified until the required structure is achieved. Here a simple method of simulating an approximation of the surface topography that will result from a computer numerically controlled (CNC) laser machining program is presented for glass and silicon. The simulation allows rapid prediction of the etch depths, workpiece contours, resulting structuring and machining artifacts. It was found that the simulated surface topology closely matched that of the structures machined in each material (4% of the maximum etch depth for borosilicate, 7% for sodalime and 9% for silicon). A non-planar microfluidic channel system with through-substrate ports was produced in both types of glass and silicon. The design took 12 min to simulate and 74 min to machine, and the simulation was accurate to within 4 μm of the machined glass substrate.

We describe a number of experiments devoted to compensation for aberrations in the primary mirror of a telescope using a volume dynamic holography technique, where the writing and reading of the hologram are carried out indepeadently.Three sets of experiments demonstrating holographic aberration correction have been performed. In all cases transmitting holograms were formed in photorefractive crystals such as BSO and SBN. In experiments with a small diameter primary minor the image is formed by a multicolor point-like object. The system includes an unit wich compensates for the hologram dispersion. The aberration correction of a six-segmented primary mirror of 1 50 mm in diameter is demonstrated in conditions where there is a pronounced difference in the wavelengths of the recording beams and that of the source observed (AX=O.12 tim). The experiments on observation an extended object of continuous spectrum (&=O.35 tm) with a single primary mirror of 1 50 mm diameter have been also made.All these experiments indicate an efficient compensation for distortions ofthe primary mirror by the hologram.