Hi,

there are several questions, before can recommend:

What wavelength do you need?

Do you need any special features, like modulation, fiber coupling, pulsed opertaion?

Hi David, sorry for not providing more detail... 

We are currently using, 100 mW DPSS 473 nm, TTL modulation, fiber coupled lasers, typically pulsed at 1 to 4 ms with 100 Hz stimulation trains. 

Hi, the linked ones are reliable manufacturers, but there must be many other. And these lasers can be suitable for you.

If I'm right you measure the laser power after the fiber. Is there any adjustment possibility at the fiber coupling? Its possible that your laser is stil perfect just the coupling needs to be fine tuned.

http://lasos.com/products/dpss-laser?gclid=CK2-8Omc_cYCFXDHtAodsRoGkg

http://www.coherent.com/downloads/COHR_OBIS_Family_DS_0615revH_5.pdf

http://www.laser2000.co.uk/product.php?no=2283

http://www.oxxius.com/High-performance-laser-diode

Hi David, you have highlighted some new suppliers to me and I will follow these up - thank you.

Indeed, with so many suppliers, I was looking for some personal recommendations since a trial and error approach is not so affordable :-) 

Our experience with a number of companies based in China is that the lasers are affordable, but loose power over the course of months and repair times are long (> 6 months on one occasion). With these particular lasers, fibers are directly coupled without the possibility to adjust, so if the fiber breaks or becomes misaligned, they must be returned for repair.

Thanks again for your suggestions!

I have been using DPSSL from Cobolt, Inc (US HQ in San Jose, CA). They are compact, high power, and very stable. They have mainly CW but I think they also offer pulsed ones. They have a wide array of nominal wavelengths available. Not sure about 473 nm. Check them out:

http://www.cobolt.com

we have good experience with the Coherent OBIS Laser family (375,405,488,532,640). We are using them since 4 years . Stable output power, can be use in CW and pulsed mode...