before vowels phaner-, word-forming element meaning "visible, manifest," especially from 18c. in biology, from Greek phaneros "visible, manifest, evident, apparent," from phainein "bring to light, cause to appear, show," from PIE root *bha- (1) "to shine." Opposed to crypto-.
"optical instrument which by means of a lens or lenses magnifies and renders visible minute objects or details of visible bodies," 1650s, from Modern Latin microscopium, literally "an instrument for viewing what is small;" see micro- + -scope. The dim southern constellation Microscopium was among those introduced by La Caille in 1752.