Measurement principle of Birefringence Measurement System PA/WPA series.（2/4）
Four articles explain the understanding of birefringence and the measurement principles and features of our equipment.
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.
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
・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
Continue to next page
- #Birefringence & stress strain measurement solutions
- #2-D Birefringence Measurement System
- #Birefringence Measurement System
PA Series PA-micro / PA-micro-S
This equipment measures birefringence and phase difference with high resolution of 5 million pixels at high speed, for low phase difference with a measurement range of 0 to 130 nm. A type that can measure birefringence with microscope FOV. The included microscope can be selected either Olympus or Nikon
By using the near-infrared band for the measurement wavelength, this system can measure birefringence/phase difference distribution even for materials that are opaque to the naked eye. Suitable for measurement targets that transmit near-infrared wavelengths, like chalcogenide lenses, LiDAR automotive components, etc.
This product is very effective if evaluation with high spatial resolution is essential.With the WPA series, it is possible to measure a phase difference of about 3000 nm by selecting three different wave lengths and comparing and calculating the phase difference at each wave length.