Categories
Research

Butterfly laser diode mount

We've put together a few of these butterfly laser-diode mount + driver combos. It combines a heat-sinked butterfly mounted laser-diode with a current/temperature controller by Wavelength Electronics. The assembly is low enough to fit into a 1U (~44 mm) high 19" rack-enclosure.
bfly_mount_v1_assembly_2013sep3 bfly_mount_v2_assembled

The 14-pin laser-package (yellow) is held in place by ZIF clamps/sockets 5253-100-07S (standard) and 5253-100-07R (reverse) from from Azimuth Electronics (grey in the CAD drawing, black in real life). The Wavelength Electronics LDTC driver controls both the laser current and temperature using the laser's own on-board TEC and thermistor. The base-plate has additional room for a heatsink and a fan, but so far I think nobody has used this feature. Semiconductor lasers have about 30% efficiency, so with anything under 1 W of optical output the dissipated heat should stay below 3-5 W.

The metal parts are an aluminium base-plate (see bfly_mount_v1_plate_2013aug26 and the newer bfly_mount_v2_plate_2013nov1). A copper riser-block (bfly_mount_v1_riser-block_2013aug26) sits on top of the base-plate and provides good heat-conduction from the laser package to the base-plate. The riser-block and the laser are bolted together with M2.5 bolts/screws (allen-bolts would be more stylish - I know!). I also made a mechanical drawing for the PCB bfly_mount_v1_pcb_drawing.

The PCB has no electronics on it (see bfly_mount_v1_schematic_2013sep3), the pins from the Azimuth sockets are just routed to 150 mil pitch screw terminals.

bfly_mount_v1_pcb_2013sep3bfly_mount_v1_pcb_assembled

See also gerbers for manufacturing: butterfly_pcb_v1_camfiles or the slightly modified version dated 2013-11-14 butterfly_v3_camfiles

screwterminal_pcb

There's an additional mini-pcb for screw-terminals on the input side of the LDTC controller. screwterminal_camfiles_2013-09-12

Our in-house design won't win any prizes for design or style, but it does the job. Here are a few pictures of commercial butterfly mounts. Some combine the current/temperature driver with the mount, others just have D-sub connectors for external current/temperature controllers.