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Is it possible to use a laser with built-in pre-chirp instead of using the external, custom prism-based pre-chirp?

At 970nm, we found that >35,000 fs2 of negative GDD was necessary to fully compensate for the GDD of the whole microscope system.  As far as we know, this far exceeds the amount that any commercial pre-chirp can provide, whether it's a stand-alone device or internal to a laser, which is why we implemented our own custom prism-based prechirp that can have a very large (~8ft) separation between prism passes.  A system that can only provide half of that negative GDD (-17500 fs^2 @ 970nm) would result in 100fs pulses being stretched to ~500fs at the brain, dramatically lowering signal level.

It is possible to sequentially add pre-chirps, so it might be possible to achieve the necessary GDD by combining a laser-internal pre-chirp with a commercially available external pre-chirp.

One must be careful when looking at negative GDD specs, as they are highly wavelength specific.  Pre-chirps can provide much more negative GDD at bluer wavelengths than red.

What is the smallest air table that can be used with the 2p-RAM?

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