tranaglyphs

Tranaglyphs are red and green targets that produce binocularly fusible, usually stereoscopic, images when viewed through red and green filters, and the term is sometimes used as a synonym for anaglyph.¹ In vision therapy, the patient views tranaglyph slides through red/green glasses, and certain objects on each slide are seen only by the right eye or only by the left eye.² Those objects serve as suppression clues, and the correct response is a single, clear picture with all the suppression clues seen at the same time.²

Variable tranaglyphs, such as the Bernell Series 500 and 600, are used to increase the amplitude and velocity of positive and negative fusional vergence and to shorten its latency, the same objectives as variable vectograms.³ The two techniques differ in printing alone, with vectograms printed in Polaroid material and tranaglyphs in red and green, and one set of vectograms costs about 8 to 10 times as much as one set of tranaglyphs.³ Suppression is a more significant problem with tranaglyphs, so vectograms are preferred in the office, and tranaglyphs are sent home to reinforce therapy once binocular vision has improved.³