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What John is referring to below already has a name: "the optical spectrum." That is the range of EMR that can be manipulated with transparent lenses. In the far IR the lenses are indeed unusual to most people since they are made from exotic salts. (Your skin oils and moisture will aggressively attack many of these materials. Gloves are absolutely required for handling.)I do recall some accounts of people who had their lenses removed because of cataracts, and the glasses passed enough of the UV spectrum to allow them to see some UV.