tunable laser diode head

This is a thermal fixture for a SANYO DL-7360-223H laser diode. Mud it up with thermal paste along with a NCP15XH103F03RC thermistor and two 50 Ohm (1/2 watt) resistors as heaters that all get placed in their respective holes. Then mud up the gaps between the heater blocks and the central island containing the laser diode and thermistor. Mount a high NA lens on the lensholder block, slide it onto the track to collimate the LD output and then encase the whole thing in styrofoam with a window. Find the temperature and LD current at which it you get the wavelength you want (here I tuned it to the Rubidium resonances, red; green are the simultaneously recorded Fabry Perot resonances) and lock the temperature with a digital control loop (via an arduino, code below). Yes, the laser diode's spectral width is thin enough to get excellent SAS resonances! Lots of fun with $2.

/* Full oven for thermoregulation of small laser packages

pin3 : OUT PWM output for the heater mosfet