THORLABS PAX1000 User Manual

© 2019 Thorlabs GmbH77
PAX1000
The ER at 100% polarized light (DOP=100%) can be expressed as
For a lower degree of polarization DOP, the maximum and minimum normalized power will
change:
The extinction ratio of strongly polarized light with a DOP < 100% can be written then:
The following table lists ERs calculated for different DOPs between 90% and 100%. This
demonstrates that the impact of the DOP on the ER of linearly polarized light can be significant.
Degree of Polarization [%]
Extinction Ratio [dB]
100
¥
99.998
50.00
99.99
43.01
99.98
40.00
99.95
36.02
99.90
33.01
99.5
26.01
99.0
22.99
98.0
19.96
90.0
12.79
This illustrates the importance of correcting the ER measurements made by the polarimeter to
take into account DOP. Working with the measurement example , the correction for DOP can
be made to the value of ER that was previously corrected for ellipticity. That corrected value
was 19.93 dB (Equation [1] ).
Assuming a DOP < 100%, an equation to correct for DOP can be derived as follows.
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THORLABS PAX1000 Specifications

General

Brand	THORLABS
Model	PAX1000
Category	Measuring Instruments
Language	English