The 191 Gonioreflectometer Heads measure the spectral reflectance of surfaces over the range of 380 to 1100 nanometers. Different model cover both specular reflectance, and diffuse reflectance, or both. The illumination and collection microscopes are mounted in a calibrated semi-circular sector assembly with independent angular adjustment capable of measuring angles down to 20 degrees included angle, 10 degrees incident angle. Small area illumination and collection viewing allow the unit to separate front and back surface reflections of thin samples.
A quarts halogen lamp provides illumination through the illumination microscope. Reflected light from the test piece is collected in the collection microscope integrating cavity. The 191 is coupled via a fiber optic probe to the Gamma Scientific RadOMA spectroradiometer.
The 191C comes with a viewing eyepiece that is inserted in place of the integrating cavity for checking system alignment and a low reflectance glass sample traceable to N.I.S.T. Standards. Specular reflectance calibration data is provided in increments of 10nm from 300 to 2000 nanometers at angles of an incidence of 10 to 45 degrees in 5 degree increments. They are provided in the form of ASCII text files directly compatible with Light Touch Software. Tabular listings are also made available.
- 191 Gonioreflectometer Head Data Sheet PDF
- Measurement of Optical Thin Film Coatings on Glass-Gamma Scientific PDF
- Angular Reflectance measurements from 380-1700 nm (200-2000 nm with 191Q)
- Calibrated glass sample
- Viewing eyepiece
- Minimum included angle of 20° (10° incidence angle)
- Fixed angle and variable angle models available
- Diffuse and specular reflectance
- Fiber Optic coupling to measurement equipment
- Regulated quartz Halogen illumination lamp
Thin Film Measurement
Gamma Scientific’s Thin Film Measurement Systems provide isolated first surface measurement of anti-reflection coatings to 0.5 mm thick.
Gamma Scientific’s unique technology allows manufacturers to perform single sided inspection on the first surface of any glass or polished, transmissive element while excluding the second surface.