Four articles explain the understanding of birefringence and the measurement principles and features of our equipment.

1. Basics of Birefringence Measurement
2. Measurement principle of Birefringence Measurement System PA/WPA series.
3. Basic Structure of the Systems & Measurement Examples
4. Range Limitation and its Extension by WPA Series

Basic structure of Polarization Imaging Sensor

Microscopic size polarization filters are integrated and placed in front of a CCD image sensor

Please also see this page.　About Special Image Sensor Manufacturing Technology

Principle of Polarization Imaging Sensor Technology and Measurement

Computation of polarization information from intensity at 4 neighbor pixels

[Relation between input polarization and intensity pattern]

[Computation principle ]
Intensity is supposed to describe a sinusoid.
By knowing only 4 points of the curve, it is possible to recover the whole set of information for any input polarization.

Polarizer angle

Intensity pattern is linked to the state of polarization at each location

Birefringence data (phase shift and axis orientation) is present at each point as quantitative data.

Measurement example: lens

Phase shift distribution

Axis orientation

・Detailed quantitative evaluation and comparison is possible between multiple sets of data.
・The slightest differences between two sets of data are easy to spot on displayed images.

Phase along lens circumference

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