|MadSci Network: Physics|
Most if not all paints reflect some color and absorb others. In natural sunlight, identifying colors or paints appears to be rather simple thru our sensitive eye brain interface. At this time in history, marking or identifying specific structures, ie. metals, plastics in daylight for content is limited to what seems unaided visual physics. Perhaps these items could contain pigments, not harmful to humans and plants that are visually color different with the aid of some type of inexpensive goggle or optic lens in natural daylight. In day light frequescies of the sun, stimulation of these invisible colors could identify the material make up. PVC one color, polycarbonate another, brass still another...and so on. Accurate separation of waste or discarded material could maybe sorted easily thru the use of special glasses in the daylight. Detection of stollen goods invisibly marked could be identified in natural daylight with the use of "special" glasses. Artificial lighting such as 'Black light' or infra red would not be necessary...just the glasses and pigment and the sun.
Re: Is there a paint that is invisible in daylight except with glasses?
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