answers verified to pass 2025/2026
Three Elements Effecting Optical Properties - correct answer ✔Light Source - reflectance curve that
measures the intensity of reflected light. as a function of wavelength
Material (object) - usually the variable in the measurement.
Detector - may be an instrument; will be selectively sensitive to certain wavelengths.
Reflectance - correct answer ✔The intensity of reflected light at a particular wavelength relative to a
perfect diffuse reflecting material.
Reflectance Measurements - correct answer ✔Most measurements made in the industry are made in
the blue region of the wavelength spectrum (~450 - ~550 nm).
Subscript on R Values - correct answer ✔Indicates the number of paper sheets backing the sample
sheet.
R_0 - correct answer ✔Zero indicates no backing paper sheet (just a black body)
R_Infinity - correct answer ✔Infinite number of backing sheet
R_89 - correct answer ✔Backed with 89% reflectance body
Brightness of a Paper Sheet - correct answer ✔R_Infinity at 457 nm
Kubella Munk Theory - correct answer ✔A theory that uses thin layer made up of small particles to
describe the interaction of light with a material. 2 coefficients are determined using this theory, the
scattering coefficient, S, and the absorption coefficient, K.