COLOUR ASSESSMENT APPARATUS AND METHOD

摘要

A method of colour assessment of a sample (10) with respect to a reference illuminant, includes illuminating the sample (10) with a light source (12) that comprises a fluorescent lamp (18) and a plurality of light-emitting diodes (24). The spectrum of the LEDs (24) supplements the spectrum of the fluorescent lamp (18) to reduce deviations between the combined spectrum of the light source (12) and a target spectrum. The target spectrum may be that of the reference illuminant or it may be adjusted to make allowance for known properties of a colour assessment cabinet (2) or an observing instrument (16). The LEDs (24) may be arranged so that their light passes through the bulb of the fluorescent lamp (18), which thereby acts as a diffuser. Alternatively, the LEDs (24) and the fluorescent lamp (18) may be located in a housing (31) from which their light can only reach the sample (10) after being mixed by reflection from multiple facets (34).