Introduction to CIE Chromaticity System
CIE is the abbreviation of Commission Internationale de I'Eciairage. The CIE colorimetry system is based on standard lighting and viewing conditions, standard observers, and theoretical tristimulus values, and is an accurate scientific system that quantitatively expresses and measures colors with numbers. Founded by the CIE organization in 1931, it has been supplemented and revised several times in 1964 and 1976, and has become a relatively complete system now.
How does the CIE colorimetry system express colors
CIE chromaticity system expresses color with CIE Yxy, CIEL*a*b, CIE L*c*H°, etc. Among them, the more commonly used and more convenient to use is the CIE L*a*b color space, followed by CIEL CIE L*c*H° color space.
Standard lighting and observation conditions recommended by CIE
The standard illumination and observation conditions suggested by CIE have the following 4 combinations.
(]) ili straight/45° (abbreviated 0/45) The angle between the optical axis of the illuminating beam and the normal to the surface of the sample should not exceed 10°. Observe in the direction of 45°±5° to the normal of the sample surface.
(2) 45°/vertical (abbreviated 45/0) the sample can be illuminated by one or more beams of light, the angle between the axis of the illuminating light and the normal of the sample surface is 45°±5°, the observation direction and The angle between the normals of the samples shall not exceed 10°.
(3) The angle between the optical axis of the vertical/diffuse (abbreviation 0/d) illuminating light and the normal to the sample surface should not exceed 10°. The reflected flux is collected by the integrating sphere beam. The included angle between any ray of the illuminating light and its axis should not exceed 5°. The size of the integrating sphere can be arbitrary, and the diameter is generally 200mm.
(4) Diffuse/perpendicular (abbreviation d/0) diffusely illuminate the sample with an integrating sphere. The angle between the normal of the sample and the beam axis of the lake view should not exceed 10°. The integrating sphere can be of any size, but the hole in the The total area of the reflector cannot exceed 10% of the total reflective area in the integrating sphere. The angle between any ray of the test beam and its axis should not exceed 5°
