This book describes all optical properties of wooden materials, including definitions and measurement methods of optical parameters such as absorbance, diffuse and specular reflectance, colour and gloss. Basic knowledge regarding the reflectance measurement in the ultraviolet, visible, near- and middle infrared radiation ranges is also discussed. It examines conducting correct optical measurements, as well as introduces the validity limits of the individual methods. Steaming as an environmental-friendly colour modification process is introduced by the description of the steaming properties...