LMK BLUE LIGHT HAZARD

The EN 62471 standard covers the photobiological safety of lamps and lighting systems. It specifies limit values for various effects on the eye. Among others is the blue light hazard (BLH) of the human eye. These limits and thresholds can be monitored by performing measurements.
Measurements with the LMK are based on the determination of the weighted radiance Le(BLH) (λ) by spectral filtering with an all-glass filter.
Depending on the standardized classification into risk groups, certain measurement angles or aperture angles must be used: 100 mrad (5.73 °), 11 mrad (0.63 °), or 1.7 mrad (approx. 0.1 °).
To measure the blue light hazard (BLH), the filter wheel of the LMK color must be equipped with a filter glass that is matched to the blue light hazard sensitivity function. When using the BLH filter glass, the measurement result is calibrated to the absolute radiation [W / sr * m²] evaluated with BLH. When you take a measurement image with this filter glass, the information contained in the measurement image is linked to the BLH-weighted radiance Le (BLH) (λ).

Display of the spectral BLH adaptation of a typical LMK