I am now designing an experiment that consists of a 400 nm short pulse (~300 fs). In the experiment, we need to magnify the transverse profile of the pulse by 100x. That's the problem.
I was considering using microscope objective lens, but it turned out that it has a lot of lenses and could stretch the pulse a lot (we could tolerate stretching by up to ~7 mm glass, but not more). Another thing that I considered was using spherical mirror for the magnification system, but I had a bad experience using spherical mirror (the astigmatism could spoil the result really much). Now the candidates that I have in mind are using (1) off-axis parabolic (OAP) mirrors and (2) toroidal mirrors. I know both of them suffers from comatic aberration, so my questions are:
- Is comatic aberration usually a bad thing or does it usually spoil experimental data?
- Are there any difficulties of using OAPs and/or toroidal mirrors?
Any suggestions and comments are welcome.