World Intellectual Property Organization (WIPO).
G02B 1/10 · · Optical coatings produced by application to, or surface treatment of, optical elements G02B 1/11 · · Anti-reflection coatings G02B 1/12 · · by surface treatment, e.g. by irradiation G02B 5/20 · · optical FILTER(S).
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United States Patent and Trademark Office (USPTO)
