X4 Light Analyzer
LDM-9812 Spot Luminance Sensor

The X4 Light Analyzer is designed for all types of light measurements in absolute radiometric and photometric units. To accomplish this the X4-DE base device featuring a diode array spectrometer can be combined with different detector heads to form the different required measurement geometries. The LDM-9812 is a spot luminance measurement detector for use with the X4 featuring a focusable lens with viewer optics for measurement distances from 30cm to infinity. An optional 1:1 lens adapter enables measurements at shorter distances. The X4 Light Analyzer with LDM-9812 sensor employs two sensor technologies. The integral detector matches the CIE photopic spectral response. It offers wide dynamic intensity light measurements with the superior linearity of photodiodes. The diode array spectrometer provides spectral measurement data in the wavelength range from 315 to 1050nm which is used for:

• on-line correction of the integral detectors spectral mismatch uncertainty
• spectrum, peak wavelength, half-band width, peak wavelength intensity
• color temperature, xy and u’v’ chromaticity values, color rendering index

The X4-DE electronic device contains the diode array spectrometer and the electronics for the integral detectors. It is supplied in a bench-top housing or in a 19” 3HE housing for rack mount use. The LDM-9812 sensor is built in a compact aluminum housing which contains the focusable lens, the viewer and the photometric filter corrected photodiode. The diode array connects to the detector head by a flexible light guide and includes a manual operated shutter for dark signal compensation as well as an optical density filter for increased dynamic range. The light analyzer device is supplied with Window 7 compatible software for operation, data read out and data storage. The X4 light analyzer is calibrated for photometric sensitivity of the integral sensors and the absolute spectral sensitivity of the diode array spectrometer within the wavelength range from 315nm to 1050nm. Calibration is performed by Gigahertz-Optik’s calibration laboratory for light measurement quantities against calibration standards traceable to national and international metrology laboratories. Re-calibration is recommended every 12 months.