The three plates are of differing thickness, 6mm, 3mm and 1.5mm. Thus they present different sizes of disparity cues, thereby enabling the stereoacuity of the observer to be measured. The plates can be presented at differing distances to further vary the disparity cues.
A table in the box lid and in the Instructions Booklet shows disparities
Screens are made from best quality black wool mix cloth. The screens are stitched with radial lines at 15 degree intervals and circles at 5 degree intervals. The illustration shows exaggerated stitching but on
These fabric patches for adults are perfect for many applications when an eye needs covering. Such as to eliminate diplopia, temporarily relieve a light sensitive eye or improve a cosmesis by covering an unsightly white eye pad, or damaged eye.
The patch attaches quickly and easily inside of the glasses frame
Cardiff Acuity Test is designed especially for the hard to test age group, 12 months to 30 months. It uses familiar pictures and a procedure in the form of a game to attract and keep the attention of young children. It relies on the technique of "preferential looking" - that is, the observer