Finally, after many weeks of extensive burn-in and long-term mode stability tests, I now have a few lasers ready to go, as well a couple of highly stable diode and TEC driver boards for DIY holography lasers; details are here. Some of the lasers were sent off today for testing in real-life holography. I will report when I know more. If you are interested, contact me.
The boards are 79€ each plus shipping, with suitable Peltier element and thermistor 4€ more. The 640nm lasers go for 275€ and the 658nm between 180€ and 200€ depending on the power.
Note added (Jan 10):
I got some more lasers, the new ones have a noise detection feature built in, which is supposed to help to detect instabilities due to backreflections etc. More details are here. The extra for each laser is 20€. I sell separately the ready-to-use boards for 20€ as well, you can use them with your own lasers (a glass plate beam splitter is needed in addition).
Note added (Feb 15):
All lasers are sold out, I am not sure whether I will build more of this kind anytime soon. Right now I am looking into ECDLs to see whether they have a substantial advantage over bare diodes such as to justify the higher costs. So far it seems that the achievable stable power is not much higher as compared to bare single mode diode lasers, and the main difference, a very small line width, is not relevant for ordinary holography purposes. Stay tuned.