168193 ⎘
Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light; Systems specially adapted for particular applications; Investigating the presence of flaws or contamination in moving material, e.g. running paper or textiles; Optical details; Scanning details; Directional selective optics, e.g. slits, spatial filters Cylindrical optics