Method and apparatus for high frequency optical beam oscillation

摘要

A mechanical scanning apparatus adapted for oscillating the focus zone of a beam of radiation having high power to modify and control the nature and extent of the interaction zone on a workpiece is disclosed. The apparatus includes a compound beam adapted for being vibrated in a vibratory mode resulting in oscillatory motion of at least a first end of the compound beam; a reflective surface attached to the first end of the compound beam and adapted for focussing radiation incident thereon to a focus zone, and means for vibrating the compound beam to induce oscillatory motion of the reflective surface resulting in oscillatory motion of the focus zone. For vibration frequencies greater than the characteristic thermal response time of the workpiece material, the effect is a broadening of the interaction zone with a beam-material interaction characteristic of a reduced incident average power intensity while maintaining a high local intensity essential to the establishment of effective radiation-material coupling.