BN-LH250

Calibration standard lamp for use as reference spectral irradiance standard

One of the most common optical radiation measurement quantities is irradiance. This measures the radiation power incident on a reference surface in W / m². The photometric equivalent of radiometric irradiance is illuminance which is measured in lux. Calibrated light sources are required to calibrate instruments for measuring spectral irradiance (spectroradiometers) and illuminance (luxmeters). These sources must have a continuous spectrum over the spectral sensitivity range of the instrument to be calibrated and a calibration traceable to a National Metrology Institute (NMI). The lamps used must meet high requirements with regard to their short- and long-term stability. Halogen lamps are most commonly used for calibration. These offer a continuous spectrum from approximately 250 nm to 2500 nm. The lamps must be operated with a constant current. To calibrate the measuring instruments, the calibration lamp is arranged at a predetermined distance from its input optics, typically a cosine diffuser.

Reference standard BN-LH250

The reference standard BN-LH250 is based on a 250 W halogen lamp. This lamp exhibits excellent short-term and long-term stability due to its very stable filament. The quartz envelope itself is frosted for a more uniform radiation. The lamp base of the BN-LH250 fixes the lamp by means of a clamp. The electrical connection is made via two laboratory sockets on the stand. The protective cover with a transparent crosshair target enables the precise and reproducible alignment / positioning of the reference standard in the measuring arrangement.

Each lamp is subjected to a recorded burn-in process prior to its release. Only lamps that meet the strict burn-in criteria will be released. This controlled aging is confirmed by certificate.

Traceable calibration of spectral irradiance with ISO / IEC / EN 17025 DAkkS certificate

The spectral irradiance is calibrated in the optical radiation calibration laboratory of Gigahertz-Optik GmbH. This laboratory is accredited by the DAkkS for spectral irradiance according to ISO / IEC / EN 17025. The Physikalisch-Technische Bundesanstalt PTB acts as the technical auditor. Alternatively, more cost-effective factory calibrations are available.

Traceable calibration of illuminance

The calibration of illuminance by the optical radiation calibration laboratory of Gigahertz-Optik GmbH is undertaken as a factory calibration.

Precision lamp power supply LPS-250-BT

Gigahertz-Optik GmbH offers an optional LPS-250-BT power supply for the operation of the reference standard BN-LH250. This is characterized by the high resolution and stability required of the lamp operating current. The lamp is switched on and off with current ramping to prevent damage to the filament.