Polarization vs Rotation of the Beam Splitter

The Goal of these measurement is to understand the changing of polarization of laser beam in operation to rotation of the Beam Splitter with incidence angle fixed. We have positioned the beam splitter to 45° rispect to the laser beam.

The folowing schedule is used:



We have used three beam splitter: two B.S. of the ULO (10ZPF3-17-U ZeSn D25.4mm...two equal) and one of II-VI (II-VI ZnSe S/N: 80-120451-03 0,120 Th. PO/5%R ).

First of All we have measurement the following parameters:

1) Input Power to the Polarizator [W] - PingPOL
2) Laser Maximum Power - Plaser [W]

After we have measurement the reflected power from polarizator in operation with rotation of the beam splitter.

3) Reflected power from polarizator - Pr [mW]
4) Reflected power with no beam splitter [mW] - PsenzaB.S.

Here the result for II-VI




PsenzaB.S = 55 mW.
PingPOL = 12.92 W
Plaser = 13.53 W

With this condition we have changed casualy the incidence angle and we have repeated the measurement:




In the following picture the compare between them:


I think that the angle in order to have the minimum reflected power is not depend on incidence angle of laser on beam splitter.

Here, instead, the results for ULO 1
PsenzaB.S = 69 mW.
PingPOL = 11.66 W
Plaser = 13.20 W




With this condition we have changed casualy the incidence angle and we have repeated the measurement:




In the following picture the compare between them:



I think that the angle in order to have the minimum reflected power is not depend on incidence angle of laser on beam splitter.

Here the results for ULO 2
PsenzaB.S = 69 mW.
PingPOL = 11.63 W
Plaser = 13.18 W




With this condition we have changed casualy the incidence angle and we have repeated the measurement:





In the following picture the compare between them:


I think that the angle in order to have the minimum reflected power is not depend on incidence angle of laser on beam splitter.

The beam splitter of the ULO are the same...but i think that the result are different......