Polly Dulley


We have investigated the effect of glare upon contrast sensitivity (CS) and high and low contrast logMAR acuities of 30 subjects classified into three different pigment groups (10 subjects in each group). The 'fair' group contained fair-haired blue-eyed Caucasians; the 'dark' group, dark- haired brown-eyed Caucasians and the 'Asian' group subjects of Indian subcontinent descent. Subjects were aged between 18 and 24 years. CS was measured at five spatial frequencies ranging from 0.9 to 24.3 c.p.d. using a CRT-based system. LogMAR acuity was measured using 90% and 10% contrast charts viewed from 4 metres. The mean luminance of the CRT and the chart background were matched. Measurements were made without a glare source and then with a Brightness Acuity tester (BAT) at the medium and high glare levels. Without glare there was no significant difference in the mean CS for each of the three pigment groups. All subjects showed a reduction in CS with glare particularly at the higher spatial frequencies but there were marked differences between subjects. The 'Asian' and 'dark' subjects in general showed a smaller reduction in CS than the 'fair' group particularly with the BAT on the high setting. For the high glare condition, there was a significant difference between the mean CS for the 'fair' group and the other two groups at all spatial frequencies above 8 c.p.d. (pTHE COMPARATIVE SURFACE SPOILATION AND CLINICAL PERFORMANCE OF TWO DAILY-WEAR DISPOSABLE LENS SYSTEMS


Year: 1992

Program Number: 1:45 pm

Author Affiliation: n/a

Co-Authors: B.Sc.(Hons.) M.B.C.O., Alison B.Sc.(Hons.), W. Thomson PhD. B.Sc(Hons.) M.B.C.O., Angela PhD. B.Sc.(Hons.) M.B.C.O.

Co-Author Affiliation: n/a

Room: Ireland B