POLARIMETER DEVICE PROJECT

Design, construction, tuning of spectroscopes
Information and discussion about softwares (telescope remote, autoguiding, acquisition, spectral processing ...)
Joan Guarro Flo
Posts: 704
Joined: Thu Nov 03, 2011 8:50 pm

Re: POLARIMETER DEVICE PROJECT

Post by Joan Guarro Flo »

Hello,

In this picture, you can see a comparison of a polarimeter design and The-Maid polarimeter, also some prices of their optical components.

Regards, J. Guarro.
Attachments
COMPARISONS2.png
Martin Dubs
Posts: 143
Joined: Fri Jan 06, 2012 9:16 pm
Location: Maienfeld, Switzerland

Re: POLARIMETER DEVICE PROJECT

Post by Martin Dubs »

Hi Joan,

I have followed your polarimeter project with great interest. Looking at your newest Project, Maid, I noticed that you position the HWR after the slit. I do not think that this a good idea. According to vector theory of diffraction, a slit produces some amount of polarization (similar to the polarization effect of a linear grating or a wire grid polarizer). I could not estimate the size of the effect, my books on diffraction theory only give results for one polarization, so I do not know if this is a serious problem. However I strongly recommend to place the slit aftrer the halfwave plate, in order to eliminate possible effects of the slit polarization.

Clear skies,

Martin
Joan Guarro Flo
Posts: 704
Joined: Thu Nov 03, 2011 8:50 pm

Re: POLARIMETER DEVICE PROJECT

Post by Joan Guarro Flo »

Hallo Martin,

Many thanks for your advice! I have just modified the drawing after reading your feedback.

The-Maid aim is try to get a range from 3700 to 8500 Angstroms, instead of the 4200 to 7550 The-Giver ones, and Thorlabs' AHWP10M-580 is an adequate Half-wave retarder, really the only one that I know.

A question for you, The-Giver has the Half-wave polymer retarder before the Alan Gee II Telekompresor, following the suggestions that Gary Cole gave
me during its design. Now, due to in fact an issue size, I put the Alan Gee II first in The-Maid drawing. What consequences do you think it would have?

Many thanks again, Joan.
Attachments
COMPARISONS4.png
Post Reply