X4 Light Analyzer
X4-BTS Sensor
SRT Lens Adapter

The X4 Light Analyzer is designed for maximum light measurement flexibility in the most common light and color measurement units. To accomplish this the X4-DE device with integrated diode array spectrometer is combined with different sensors to form various measurement geometries. With the X4-BTS sensor it measures photometric illuminance and radiometric irradiance in absolute light measurement units. The measurement application range of the X4-BTS sensor can be extended using SRT front lenses. The SRT front lens series is designed for luminance and radiance measurements on large field luminous areas. These are non-focusable lensed barrels with 1°, 2°, 5° or 10° fields of view that are mounted onto the X4-BTS sensor using the SRT-M45/36 adapter. Optional quartz lenses are available for measurements in the UV-A spectral range. The X4 Light Analyzer with X4-BTS sensor employs two sensor technologies. The integral detectors match the CIE photopic, scotopic or radiometric UV-A, VISIBLE and NIR spectral sensitivities. They offer 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. The measured spectral data is used for:

• on-line correction of the integral detector(s) spectral mismatch uncertainty
• test source spectral details like peak wavelength, half band width, peak wavelength intensity
• color values such us color temperature, xy and u’v’ chromaticity values, color rendering index

The X4-DE instrument houses 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 X4-BTS sensor is built into a compact 45mm diameter housing which contains up to four photodiode detectors behind a shared 11mm diameter diffuser window. The diode array is connected by a flexible light guide to the X4-BTS detector head which includes a manually operated shutter for dark signal compensation as well as an optical density filter for increased diode array dynamic range. A remote controlled shutter is alternatively offered. The X4 light analyzer with X4-BTS sensor can be combined with optionally available accessories like integrating spheres, spot luminance and radiance detector and goniometric measurement bench. Windows 7 compatible software is supplied for operation, data read out and data storage. The X4 light analyzer is calibrated for photometric and radiometric 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.