The CL-500A is a compact, lightweight illuminance spectrophotometer that can be used not only for illuminance measurements but also for spectral evaluation of high class next generation lamps such as LEDs, OLEDs and EL illumination. The CL-500A makes use of multiple sensors and an optical grating which enables it to measure and evaluate CRI or Color Rendering Index. CRI is a quantification of the color-rendering properties of a lamp or other light source, and was defined to provide objective criteria. The CL-500A will measure and display the CRI (Ra) as well as the individual indices from R1 thru R15. Another benefit to using a sensor based detector is the ability to display spectral distribution in graphical form. The fact that the CL-500A is a sensor based instrument means it is well suited to measuring narrow bandwidth light sources including LEDs, OLEDs, Ultra High Pressure lamps (UHP), etc. Photometric units are also available at any time. These include illuminance in lux and foot-candle, color temperature (CCT) in Kelvin, chromaticity in xy and u’v’ color space, tri-stimulus values XYZ, Duv, dominant wavelength and excitation purity.