Dazzling op-art. A term invented by Time Magazine. And the trompe l'oeil of the mid-20th century... 1. Op-art, Plate, blank made by Hutschenreuter, designed by Piero Fornasetti, Italy, 1950-1960. 2. Untitled screenprint on plexiglass by Bridget Riley. Great Britain, 1965. 3. Untitled (Fragment 5). screenprint on plexiglass by Bridget Riley. Great Britain, 1965.