Patent attributes
A light curtain safety system for a semiconductor device handler that includes a programmable control unit and a robot mechanism that is selectively operated in response to signals generated by the control unit. The light curtain safety system includes an apparatus for generating a light curtain such that accessing the robot mechanism requires breaking the light curtain. The light curtain safety system detects an operating state of the semiconductor device handler using signals generated in the control unit, and allows de-activation of the light curtain apparatus only when operating state of the semiconductor device handler is in a predetermined “safe” operating state. When the light curtain apparatus is active and the light curtain is broken, the light curtain safety system causes the semiconductor device handler to terminate power flow to the robot mechanism.