PMA 50 by Bruker Optics

The PMA 50 module has been dedicated developed for Polarization Modulation measurements.

Both linear dichroitic measurement techniques like PM-IRRAS and circular dichroitic experiments like VCD spectroscopy can be realized using this accessory. It can be adapted to Bruker TENSOR and VERTEX FTIR spectrometers.

All optic and electronic components in the PMA 50 module are optimized for the Polarization Modulation. Both linear dichroitic measurement techniques like PM-IRRAS and circular dichroitic experiments like VCD spectroscopy can be realized using this dedicated system.

The core of the Polarization Modulation technique is the Photoelastic Modulator (PEM) with a nominal modulation frequency of 42 kHz. With the help of the parallel 24-bit dual-channel data acquisition technology the sum and the difference signals can be collected simultaneously with highest sensitivity. The PMA 50 module exhibits short beam path, and therefore provides optimal S/N ratio and stability.

In combination with optical filters and the automated software controllable internal aperture in TENSOR and VERTEX spectrometers the signal quality can be further optimized with respect to the desired spectral range and sample size. To reach the highest performance in Polarization Modulated Applications, the polarized light is focused on the detector element by a lens providing that only non-polarizing optical components are used after polarization.


PMA 50 Features:

• Photo Elastic Modulator (PEM) ZnSe, 42 kHz nominal frequency, AR coated
• All optic and electronic components optimized for Polarization Modulation
• 24-bit dual-channel data acquisition technology
• Full-integrated demodulation electronics for compact design and easy operation
• Investigation of ultra-thin layers on metal surfaces without reference measurement or water vapor absorption
• Purity control of enantiomers
• Determination of absolute structures for enantiomers