The LRS-455 is a NIST traceable, highly stable, self-contained luminance / correlated color temperature / spectral radiance calibration standard. It is an ideal tool for checking or calibrating photometers and spectroradiometers.

The LRS-455 system includes an integrating sphere containing a quartz halogen and photopically corrected detector. The measuring port of the sphere is extremely uniform assuring accurate results regardless of the sampling size of the measuring instrument.
The sphere assembly features a built-in filter holder capable of hold 81.3 mm x 64.8 mm x 13.7 mm filters making measurements of transmissive media quick and easy.

The system controller contains a highly stable lamp power supply and photometer. To help extend the life of the lamp, the power supply ramps up slowly when the system is turned on, and ramps down slowly when the power is turned off.

The luminance can be varied while maintaining a constant color temperature, and inversely, the color temperature can be varied while keeping the luminance constant.