Safety system for laser working of metals - where pilot laser and opto-electronic safety circuit switch main laser off when removed from workpiece

Abstract

Abstract This is an addn. to 2321137, which described a safety device protecting operators from laser rays, esp. when using a flexible waveguide ending in a handpiece contng. a focussing lens. The beam of the main laser is switched on or off via a beam from a pilot laser, where beam is in the visible spectrum and is linked to an electro-optic lock fitted e.g. on the switch for the pump light used on laser. In this addn. the pilot beam is strongly polarised, and the degree of polarisation of the reflection or back-scattering from the workpiece controls the lock. The handpiece pref. contains two detectors, each with a polarising filter, one with its transmitting direction parallel with the polarising direction of beam, whereas that of the other filter is at 90 degrees to the polarising direction of the beam. The filters are pref. polarising foils.

Inventors

• 👤 Thorsteinn Dipl Ph Halldorsson

Bibliographic Details