Refractive index knowledge is one of important parameter when physical properties of materials are investigated. It is also known that temperature variation and wavelength are also effect on the measurement results when materials are characterized. Therefore fast and accurate measurements are needed to measure especially refractive index properties of material. In order to cover this poverty we established we established a computer controlled an optical facility in National Metrology Institute of Turkey, based on laser beam displacement technique. Basic components of established facility are laser sources, sample holder, knife-edges and detectors. In order to compensate fluctuations arising from laser instability we used electro optic modulator that kept the intensity of lasers stable at around 10-5. A temperature controlled sample holder was used to measure temperature dependence of materials. The displacement of laser beam was determined using knife-edge, which moved using a computer controlled servomotor. The refractive index than was found
from displaced laser peak signal using designed trap detectors based on three single-element silicon photodiodes.
The luminous intensity unit and traceability in derived units of illuminance and luminance were realized using new detector-based approach at the National Metrology Institute of Turkey. Services in photometry were enlarged to perform high-level illuminance and luminance meter calibrations, namely at levels up to 5000 lx and 5000 cd/m2 by using the working standard photometer heads, precise apertures and integrating spheres on the 6 m long photometric bench. Working standart photometer heads which consist of a single silicon photodiode, V(λ)-corrected filter, precision aperture and a cosine corrected diffuser were calibrated for luminous responsivity in A/lx. For precision in the measurements, positions of illuminance meters and photometer heads are compared by using step motor controlled translation stages. The measurements are carried out at the color temperature of 2856 K and in the conditions where the inverse square law is applicable. The same photometer heads are used to measure luminance unit. The purpose of the work is to present established photometric systems and describe capability which is being applied at UME for the realization of calibrations of illuminance-meters and luminance-meters.
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