Learning outcomes of the course unit
The course gives the physical basis useful to study colorimetry. Particular attention is devoted to the colour measurement techniques.
Knowledge of mathematical analysis and analytical geometry. Basic knowledge of geometrical and physical optics and of the light-matter interactions.
Course contents summary
Physics of light
The electromagnetic radiation: waves and photons. Physical properties of the electromagnetic radiation. Polarisation of light. Spectral power of an electromagnetic radiation. Radiometric and photometric quantities. The irradiance and the inverse square law.
The color definition following CIE. The tristimulus values. The Colour Matching Functions. The light sources and the CIE standard illuminants. Colour of a light source. The black body radiation. Lamps and their colour temperature. Colour of a body by reflection, transmission and diffusion of light. The colour dependence from the geometric arrangement of light source, body, and observator. Color dependence on ambient temperature and humidity.
The light-matter interaction processes as colour modifier
The matter polarization and the refraction index. Dependence of the reflection index by the light wavelength. Reflection and refraction. Snell and Fresnel laws. Transmission, absorption and emission of light. Scattering of light. Rayleigh and Mie scattering. The perfect reflector and the lambertian surface. Light dispersion. Huygens principle. Diffraction and interference of light. Diffraction gratings. Spectral analysis of light by optical filters and monochromators. The optical spectrometer.
Optical parameters and colour specification
Definition of spectral reflectance, spectral transmittance, spectral reflectance factor and spectral transmittance factor. CIE’s optical standard geometries for reflectance and transmittance measurements. Helmoltz reprocity principle. Lambert-Beer law. Kubelka-Munk law. Saunderson equation. Measurements of the optical quantities using the spectrometer and the integrating sphere. The spectro-gonio-radiometer and its use.
Trichromatic instruments: colorimeters, film cameras, digital cameras and scanners. Spectrophotometric measurement of colour. Vision system imaging. Images and their properties. Fundamentals of spectral imaging instrumentation. The multispectral and the spectrophotometric techniques.
1) “MISURARE IL COLORE: Spettrofotometria, Fotometria e Colorimetria, Fisiologia e percezione” Claudio Oleari Ed., Editrice Hoepli, Milano, Italy
2) Appunti del docente.
Teaching is based on oral lessons. Students are supplied with the lecture notes used during the lessons. Students can take advantage from the teacher tutoring.
The examination includes only an oral exam. Student can take examination by agreement with the teacher.