That is a Xerox printer sled. The tube will have multi-line optics designed to enhance violet and blue, but will lase green.
The laser is set up to run at ~27 mW in the sled.
An Omni 150 or ALC Gold Box power supply will run the head.
SP heads have a self contained igniter and a lower cathode voltage, ALC heads need some additional PSU voltages for the igniter. Its not an easy conversion.
Steve
Qui habet Christos, habet Vitam!
I should have rented the space under my name for advertising.
When I still could have...