20 dioptre prism
(product code: 20DP)
- Used in the "20 base out prism test".
- One of the easiest, fastest and most
effective ways of screening for binocular vision in
- If the child is not cooperative enough
to conduct other tests, a 20 dioptre base-out prism
is put in front of one eye while shining a penlight
(or even using a captivating fixation target). If
the eyes adjust to the prism and the corneal
reflexes become straight, fusion is present which
proves the existence of binocular vision.
- Extremely useful for any optometrist /
ophthalmologist / orthoptist.