Beam shaping optical systems for high pulse energy lasers

Control of intensity profiles is important in applications with powerful ultrashort pulse lasers. Specific requirements to beam shapers: variable intensity distributions, keeping the beam consistency, operation with TEM00 and multimode lasers, high resistance, – are fulfilled by refractive field mapping beam shapers realizing wavefront manipulation using lenses with smooth surfaces. Irregular profile of input beam can be corrected using an air gap. To avoid the air break-down in the intermediate focus in imaging optical system it is suggested using field lenses displacing the energy concentration point and increasing focus spot. The paper describes beam shaper designs and optical imaging layouts, presents experimental results.