Lightweight focusing head with fast and compact adaptive mirror

Speed and accuracy in three-dimensional laser processing applications, such as cutting and welding of car bodies, is not so much limited by the availa ble laser power or technological problems, but rather by the dynamic accura cy of the processing machines. A decisive step towards a highly dynamic pro cessing machine has been taken with the development of a lightweight focusi ng head, which is presented in this article. The focusing head is designed as a modular base allowing the integration of various lightweight component s. The must important of them are a focusing mirror, a position correction mirror, and an adaptive mirror. The adaptive mirror is used for controlling the axial focus position and the focus radius, respectively. A new approac h for a fast and compact, yet lightweight adaptive mirror with a large rang e of curvature variation and good optical properties is presented. (C) 1999 Laser Institute of America. [S1042-346X(99)00304-6].