transmission absorption scattering optical coating losses


Cavity-Ringdown (CRD) Reflectometer and Loss Meter


Our reflectometer GLACIER® utilizes cavity ring-down (CRD) spectroscopy to measure the losses of advanced optical coatings down to 5 ppm, allowing the characterization of highly-reflective mirrors with up to 99.9995% reflectivity. This method provides unrivalled sensitivity compared to conventional absorption and reflection measurements, limited to the >1000 ppm range (<99.9% reflectivity). CRD loss meters repeatedly measure the losses within a cavity with a longer intra-cavity dwell time for smaller losses, resulting in increased measurement precision the lower the losses are. The device features high-speed data acquisition, enabling quick measurement recording and analysis.

Key Product Features

  • Reflectivity measurements
    • Reflectivities up to 99.9995%
    • Various angles of incidence: 5° - 45° (and 0°)
    • s and p polarization (separately)
  • Antireflective coating characterization: Reflectivity down to 0.0005% (5 ppm)
  • Simple and reproducible alignment: for 0.5", 1" and 2" optics
  • Spring-loaded mirror fixtures for reproducible mounting without strain
  • Computer and user-friendly software interface included
  • High-speed data acquisition and real-time analysis: Complete measurement and analysis within seconds
  • Available wavelengths:
    • 375 - 1550 nm
    • other wavelenghts are available upon request
  • Standard Footprint: 90 x 45 cm2 (standard size)

A family of GLACIERs to choose from. Pick the one that suits your needs best:

Number of wavelengths One Three Three*
Maximum number of wavelengths Three Four Unlimited!
Possible to add more wavelengths at a later point Yes** Yes** Yes
Wavelength range 375 — 1550 nm
(diode laser based)
355, 532 and 1064 nm
4th wavelength:
diode laser based
(375 — 1550 nm)
450 — 2000 nm
(freely selected)
Laser source Diode laser Microchip laser Supercontinuum with monochromator
Footprint 90 x 45 cm2
90 x 55 cm2 for more
than 1 wavelength
90 x 55 cm2 90 x 55 cm2
Reflectivity measurements Reflectivities up to 99.9995%
Antireflective coating characterization Reflectivity down to 0.0005% (5 ppm)
Angle of incidence 5° - 45° and 0°
Polarization s and p (separately)
Optics size 0.5", 1"
(2” and more upon request)
Software Computer and user-friendly software interface included

*Included in the basic version, more can be added.

**Factory upgrade required. For GLACIER, a bigger footprint should be considered in advance (90 x 55 cm2).