Quality Control

Fizeau InterferometerFizeau Interferometer (SOLITON MiniFIZ 300)
InterferometerInterferometer (OptoTech®)
Atomic Force MicroscopeAtomic Force Microscope (DI Nanoscope®)
Cavity Ring-Down SetupCavity Ring-Down Setup
GDD-Measurement SetupGDD-Measurement Setup

LAYERTEC conducts a great effort to guarantee the quality of current and future products.

Our sophisticated measurement equipment is used to supervise the substrate and coating production.
For instance we routinely measure

  • Surface form
  • Surface roughness / quality of the finishing
  • Spectral transmission and reflectivity
  • Spectral phase & GDD (if applicable)
  • High end reflectivity measurements over a broad wavelength range using an broadband Cavity Ring-Down setup with an OPO as light source
  • Damage threshold measurements for certain wavelengths and pulse lengths

Measurement Tools for Precision Optics

The precision optics facility of LAYERTEC is equipped with interferometers for plane and spherically curved surfaces. Plane substrates with a flatness of λ/20 (633nm) and spherical substrates with a form tolerance of λ/10 (633nm) can be provided with a protocol of the interferometric measurement.

LAYERTEC also uses a high performance Fizeau interferometer and a Twyman-Green interferometer for the form tolerance measurement of large optics in the following measurement ranges:
Plane surfaces:

  • Up to ∅ = 300mm
  • Measurement-Precision: Flatness of λ / 100 (546nm)
Spherical surfaces:
  • Up to ∅ = 500mm with a
  • Measurement-Precision:Form tolerance of λ / 50 (546nm)

The Atomic Force Microscopy (AFM) is a useful Instrument for the characterization of very smooth surfaces with an rms-roughness below 5Å. LAYERTEC has an AFM to control the special polishing processes as well as to provide inspection protocols on request.

Measurement Tools for Coatings

The inspection routines at LAYERTEC include spectrophotometric measurements of the coated optics in the wavelength range between 120 nm and 20 µm. Standard spectrophotometric measurements in the wavelength range 190 nm – 3200 nm are carried out with PERKIN ELMER spectrophotometers Lambda950®, Lambda750® and Lambda19®. For measurements beyond this wavelength range, LAYERTEC is equipped with a FTIR spectrometer (for λ = 1 μm ... 20 μm)and a VUV spectrometer (for λ = 120nm ... 240 nm).

High reflectivities in the order of R = 99.9 ... 99.9995 % are measured by Cavity Ring Down Time Spectroscopy. Actually LAYERTEC comes with various CRDS measurement systems, which can be used in the wavelength range from 355 nm to 1064 nm. Furthermore, a novel broadband CRDS setup is available, which provides the measurement of the reflectivity of low loss mirrors in the range between 220 nm and 2300 nm.

LAYERTEC is equipped with an LIDT measurement setup working at 266 nm, 355 nm, 532 nm and 1064 nm with ns‑pulses.

The measurement of absorption and scattering losses of optical thin films and bulk materials as well as laser damage threshold measurements are also available in cooperation with the Institute for Photonic Technology Jena, the Fraunhofer Institute IOF Jena and the Laser Zentrum Hannover.