Optical Layout

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Output beam from PIAA unit is F/15.213, with the pupil 1141mm before the focus.
Design is optimized for mask type 1. Mask type 1 accepts pupil diameter 5.93mm, and the illuminated pupil after the mask is 0.8722 x 5.93mm = 5.17mm The ILLUMINATED pupil size on DM should be 9.5mm. For Mask 1, the pupil size on the DM is then 10.9mm.

Overall optical design. Drawing scale and angles are approximate. Red is focus light, green is pupil light.
Picture of the optical layout, taken from above PIAA M2 & MEMS DM (not visible in this image - they would be below the frame) looking into PIAA M1, Fold M1 and the CCD camera.
Picture of the optical layout, taken from above CCD camera (not visible in this image - it would be below the frame) looking into PIAA M2.

Optical design layout details

NOTE: What is described below is the optical layout before compensations were applied. After compensations were applied, x7 and x8 turned out to be larger than anticipated, and l3/l4 were added to produce the correct focal plate scale and focal plane pacement on the bench.

After PIAA focus, first element is f=100mm lens l1. It should deliver 5.93mm pupil plane conjugated to PIAA M2.
x1 = distance between PIAA focus and lens l1.
x2 = distance between lens l1 and pupil plane.
1/x2 + 1/(x1+1141) = 1/100
x2/(x1+1141) = 5.93/75
-> x1 = 223.755
-> x2 = 107.907
x3 = distance between l1 and 2nd focus
1/x3 + 1/x1 = 1/100
-> x3 = 180.805
After 2nd PIAA focus, lens l2 with f2=200mm. It should deliver 10.9mm image of the 5.93mm pupil.
x4 = distance between 2nd focus and l2.
x5 = distance between 2nd pupil and 2nd focus = x3-x2 = 72.898
x6 = distance between l2 and 3rd pupil
1/(x4+x5) + 1/x6 = 1/200
x6/(x4+x5) = 10.9/5.93
-> x6 = 567.622
-> x4+x5 = 308.807
-> x4 = 235.909
d2 = beam size at lens l2
d2 = 5.93 x x4/x5
-> d2 = 19.19 (16.74 illuminated)
l1 = 1rst focus to DM distance = x1+x3+x4+x6
-> l1 = 1208.091
x7 = distance between l2 and 3rd focus
1/x4 + 1/x7 = 1/200
-> x7 = 1313.927
x8 = distance between DM and 3rd focus
x8 = x7 - x6
x8 = 746.305
Page content last updated: 27/06/2023 06:35:52 HST
html file generated 27/06/2023 06:34:37 HST