# Find retardation per mm

1. Sep 18, 2016

### lcr2139

1. The problem statement, all variables and given/known data Quartz is positive uniaxial crystal with ne (extraordinary axis) = 1.553 and no (ordinary axis) = 1.554.

A) determine the retardation per mm at lambda (wavelength) when the crystal is oriented such that retardation is maximized.

B) At what thickness(es) does the crystal act as a quarter wave retarder?

2. Relevant equations
retardation (delta) = thickness (t) x (no-ne)
retardation (delta) = (2pi * (no-ne) * thickness (t) ) / (wavelength)
3. The attempt at a solution
A) retardation/thickness = no - ne

B) t/delta = (2pi * wavelength * (no-ne)

Am I using the right equations? I don't think so. What are they?

2. Sep 23, 2016

### Greg Bernhardt

Thanks for the thread! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post? The more details the better.