Photometry

Beam path for spectrometers with very low divergence for the measurement of steep edge filters.
© Fraunhofer IST, Chris Britze
Photometry in practice: Beam path for spectrometers with very low divergence for the measurement of steep edge filters.

Neutral and independent testing and evaluation of optical components

Photometry represents a fundamental discipline in the field of thin-film optics. It is used for both the development of single layers and the characterization of optical filters. The spectra serve the modeling of the refractive index and layer thickness or the direct quality control with regard to the specification.

In addition to the utilization of commercially available spectrophotometers, the IST also realizes setups for specialized customer requirements, e.g. for the measurement of particularly steep edge filters or with particularly high resolution for in-situ measurements.

Available test methods for standard-compliant and customer-specific measurements

The two spectrophotometers PerkinElmer LAMBDA 950 and AGILENT CARY 5000 enable the following UV-VIS-NIR measurements:

  • Transmission in the range of 175 - 3300 nm at an angle of incidence of 0° or of 8 - 45°
  • Reflection in the range of 175 - 3300 nm at angles of incidence of 8 - 45°
  • Scattered light by means of integrating sphere
  • If required, S (TE) or P (TM) polarization

A BYK haze-gard plus for fast integral measurements in the visible spectral range allows the determination of (ASTM D-1003/D-1004):

  • Total transmittance
  • Haze (scattered light)
  • Image sharpness (clarity)

Our focus and expertise

 

Optical systems and applications