Abstract: The color and black-white stereograms for medical use were viewedby 30 Ss through an amblyoscope, which was controlled by Apple Ⅱ com-puter. The results indicate that (1) binocular sterescopic vision is for-med when alternate frequency of alternate flash phase of binocular picturesis over 7 Hz; (2) when binocular stimuli are presented alternately, thestereoscopic flicker fusion threshold to the color stereogram approximatesto 33 Hz and that to the black-white stereogram approximates to 25 Hz.The different of the two thresholds is very significant (P<.0001).

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