[f. Gr. τείνειν το stretch, extend + -SCOPE.] An optical instrument in which prisms are so arranged and combined as to increase or diminish the apparent linear dimensions of objects, while the chromatic aberration of the light is corrected.
1822. Brewster in Edin. Phil. Jrnl., April, 334 (heading). Description of a Teinoscope for altering the Lineal Proportions of Objects, with Observations on Professor Amici’s Memoir on Telescopes without Lenses…. The Instrument which I propose to describe … was invented and constructed in its simplest form about the beginning of the year 1812.
1832. Nat. Philos., II. Optic. Instr., xvi. § 110. 55 (Usef. Knowl. Soc.). Amici’s teinoscope consists of four right angular prisms, having their refractive angles different and connected by pairs.
