Method and apparatus for assessing laser temperature

摘要

The operating temperature of a laser can be assessed by determining the ratio of light of different wavelengths emitted by the laser. A copper vapor laser emits green and yellow light having two distinct wavelengths and the ratio of said wavelengths is temperature dependant. Preferably the ratio of green to yellow light is in the region of 2 to 1 for optimum operating conditions. The ratio is determined using green and yellow light filters (3, 4) having associated light dependant resistors (6, 7) forming input and feedback resistors in an operational amplifier circuit (9).