Patent attributes
A laser power control arrangement and method in an electro-optical reader for reading indicia includes an energizable laser for emitting a laser beam having an output power along a path. An internal light detector, e.g., a monitor photodiode, is mounted inside the laser for monitoring the output power of the laser. An external light detector, e.g., an auxiliary photodiode, is mounted outside the laser for monitoring the output power of the laser independently of the internal light detector. A guide, advantageously a light pipe or a diffuser, is positioned outside the laser in the path of the laser beam for guiding the laser beam from the laser to the external light detector. A controller is operatively connected to each light detector, for controlling a monitored output power of the laser beam by deenergizing the laser when the monitored output power of the laser beam exceeds a safe power level limit.
