Multiwavelength and multibeam diffractive optics system for material

Abstract

A laser apparatus having a laser that generates at least one laser beam of a fundamental wavelength, a diffractive optical element that converts the laser beam into a plurality of light beams at the fundamental wavelength, and a harmonic crystal that converts the plurality of light beams at the fundamental wavelength into respective light beams having respective wavelengths which are harmonically related to the fundamental wavelength. By splitting the laser beam into a plurality of beams before converting to harmonic wavelengths using the harmonic crystal, the crystal volume is more efficiently used and the thermal stress on the crystal is reduced. In an alternative embodiment, the invention provides for the use of a plurality of harmonic crystals in series to convert the wavelength to shorter harmonics. The apparatus employs a method of generating a plurality of laser light beams at a plurality of wavelengths comprising by generating at least one laser light beam at a fundamental wavelength, converting that laser light beam into a plurality of light beams at the fundamental wavelength using a diffractive optical element, and converting the plurality of light beams at the fundamental wavelength into a plurality of light beams which are harmonically related to the fundamental wavelength using a harmonic crystal.