Answer: microdots

AnswerCrossword Clue
microdotsA tiny tablet or capsule (of LSD)
microdotsDenoting a pattern of very small dots
microdotsMICRODOT, a copy of printed matter reduced to the size of a dot
microdotsA microphotograph, esp. of a printed or written document, that is only about 0.04 inch (1 mm) across