tachistoscope

noun Psychology.

1. an apparatus for use in exposing visual stimuli, as pictures, letters, or words, for an extremely brief period, used chiefly to assess visual perception or to increase reading speed.

noun

1. an instrument, used mainly in experiments on perception and memory, for displaying visual images for very brief intervals, usually a fraction of a second

n.

1. An apparatus that projects a series of images onto a screen at rapid speed to test visual perception, memory, and learning.