You searched for: “opaque projectors”
opaque projector (s) (noun), opaque projectors (pl)
A medium that does not pass radiation of a particular frequency band: Opaque projectors are used to view images of nontransparent materials; such as, printed sheets, pages of books, drawings, mineral specimens, leaves, etc. onto a screen by means of reflected light for lectures and presentations.
This entry is located in the following units: jet-, -ject, -jecting, -jected, -jection, -jector, -jectory; jacu-, jac- (page 6) opaqu- (page 1)