8. Glossary

Angle visuel; viewing angle

Angle between the straight lines connecting the ends of the apparent source to the observer's eye or to the point of measurement (synonyms: apparent diameter, angular extent).

Angle d'acceptance; acceptance angle

Angle of the detector limited by the field-of-view diaphragm over which illuminance and luminance measurements are averaged. There is a thermal acceptance angle γ _th and a photochemical acceptance angle γ _ph (synonyms: field of view, effective field, angular aperture).

Retinal burn; Brûlure rétinienne

Thermal retinal damage induced by radiation between 380 and 1,400 nm (visible and IR-A). 2 TLVs are associated with retinal burns. One ELV...