HCT-99D Photometer & Luminous Color Meter

The HCT-99D is portable photometer & luminous color meter for the measurement of illuminance, color temperature, xy and u’v’ chromaticity coordinates and delta uv.

The HCT-99D employs the common photometer design with separate meter and cable connected detector head to enable the operator to stay clear of the detector head to prevent reflected light or shadows from effecting the measurement. The 20mm low profile height detector head allows measurement close to the reference level.

As an illuminance meter or luxmeter the HCT-99D features a precise photometric corrected photodiode detector with cosine diffuser. It’s V(λ) spectral sensitivity matches the DIN CIE standard with f1’ error of equal to or better than 3% fulfilling the DIN Class A specification.

As a luminous color meter the HCT-99D represents the classical RGB tristimulus color meter with three filter corrected photodiodes in correlation with the Red, Green and Blue cones in the human eye. Color readings are calculated by the ratio of the detectors signals. Gigahertz-Optik has improved the standard RGB technology by adding a fourth filtered photodiode into the detector for the x short function for improved measurement uncertainty when measuring blue dominant light sources.

Optional SRT front lens adapters extend the measurement functions of the HCT-99D for luminance measurement.

The HCT-99D meter is ergonomically designed as a hand-held battery operated meter with back lit display. Operating the HCT-99D is simple. The meter set-up is supported by an easy to use menu accessed by front panel buttons. The menu allows selection of the operating mode, the display mode, the detector and measurement parameter. Once set-up all settings are stored and recalled on next power-up unless reprogrammed. In remote control operation the meter is powered through its USB interface for time and battery independent use.

Calibration is performed by Gigahertz-Optik’s calibration laboratory for light measurement quantities against calibration standards traceable to national and international metrology laboratories.