[Lee, Daniel]
We worked with Albert Lazzarini to use an instrument to measure the microroughness of the surface of the Knight Optical silicon optics. We were able to record images of the surface with ~3 mm side length. We took measurements of optics with a cylindrical barrel and octagonal barrel in the center and close to the spoke. The data as screenshots and .csv is on the nextcloud, but it is down right now. It seems the optics are flat with an rms between 0.1 nm and 1 nm, which should be small enough for our purposes. A full analysis is needed. Note that the x and y axes (in the screenshots at least) is in units of 10 μm. This was determined by knowing how much we moved the stage and by tracking a piece of schmutz. We confirmed this by moving to the side of the optics. See attached photos. See below for instructions from Albert.
Open 4Sight Focus
Click Video for live view
Red: gain too high, so lower exposure
Also change gain
Get fringes with (tip/tilt and) focus
Select Autofocus
Select Coarse Autofocus
Repeat a few times
Play with gain and exposure so there’s no railing
Better to have exposures lower
Hit measure
Can also do burst for more (ended up doing this but took a few minutes)
Can save as csv
When done:
Close program
Log out
Turn off switch
Turn off computer if files are transferred
