effect of distance

#581589
Robin Leadbeater
Participant

I am also trying to figure out if (and if so why) the distance along the laser beam changes the measured dispersion. The images showing reflections in the window suggest it does, though they will be much nearer than the typical beam distance of course. Can you see any loss of parallelism (is this a word?) between the zero order and dispersed beams?

Cheers

Robin