The conventional illuminometer calibration system usually consists of a 1 kW tungsten halogen bulb. This bulb is capable of producing an illuminance of about 5,000 lx when placed at a distance of 500 mm. To calibrate the illuminometer, an optical bench of 6 m or longer is required. The distance between the bulb and an illuminance reference sensor is adjusted depending on the illuminance level, which ranges from 50 lx to 5,000 lx. However, the current calibration system has a limited illuminance range, which excludes other illuminance ranges outside of 50 lx to 5,000 lx. Therefore, there is a need to develop a new calibration system that can accommodate a wider range of illuminance levels.

Radiometry-Photometry Technical Assistant Manager, Junghoon, from SICT, a Trescal company, presented a poster at the 2023 International Metrology Congress (CIM) on the different processes used to calibrate a compact type of Illuminance meter.