NEWBURYPORT, Mass., Dec. 4, 2015 — Gigahertz-Optik Inc. has announced the BTS256-PAR handheld spectrometer-based photosynthetically active radiation (PAR) meter for natural or artificial light source analysis. The device provides PAR, illuminance, color and spectral data, measuring photon flux density, red to far-red irradiance ratio, daily light integral and SIN ASY1, ASY2, ATP1, ATP2 irradiances. The meter also measures scotopic and photopic illuminance and ratio, equivalent visual efficiency factor, spectral irradiance, color coordinates, color temperature, delta UV, color rendering index, color quality scale, and color purity. Five user-specified spectral weighting functions can be programmed into the meter. A built-in electro-optical shutter for dark-signal compensation increases the highly linear dynamic range of the CMOS diode array detector.