This sample is the grating testing sample from a polished edge underneath and looks like this:

 _____________________
| |                   |
| | ▌▌▌   1           |
| |                   |
| | ▌▌▌   2           |
| |                   |
| | ▌▌▌   3           |
|_|___________________|

All gratings are the same frequency.

The Metricon only got a reading off the back sideas follows:

After over 30 min of testing there was no front side (SiN side) metricon Readings.

We assume the Waveguide was destroyed while creating the grating.

The following is in the wrong mode (TE) and so should be ignored. All appear to have a 0th order that is visible from most angles from 345°-354° if not more.

Below 350° the farther mode from the normal seems brighter. Above 350°, especially at 354°, the nearer mode seems brighter.

It should be noted that there are mode lines on both the top side and the bottom side of the LiNbO3.

The following are photos with and without a polarizer:

	345°	354°
Without Polarizer
With Polarizer