瞳孔大小是否會影響紅綠測試?

紅綠測試是一種視光學中用來判斷球面度數(近視或遠視)是否超過或不足的方法


紅色較清楚表示近視度數不足，綠色較清楚表示近視度數超過了，遠視則相反。


一般在做此測試時，要求在暗室中，一方面瞳孔放大，調節較為放鬆


一方面紅綠對比較為強烈。


下列實驗探討了瞳孔大小與紅綠測試的關係。


結果是瞳孔大小並不會明顯影響紅綠測試的結果


There were no significant differences between the mean 


responses under all test conditions.


但較大的瞳孔(差距4mm時)，對個體的反應較為明確。

The variability of individual responses decreased with 


increasing pupil size


我的解讀是雖然室內燈光不會明顯改變紅綠測試結果 (例如原本紅色清楚變綠色清楚)


但較暗的燈光下，是有助於被測者的紅綠判斷(較為明確、快速)。


因此還是建議紅綠測試時，室內的燈光能夠儘可能暗。

J Am Optom Assoc. 1995 Feb;66(2):87-90.

Do changes in pupil size and ambient illumination affect the duochrome test?

Rosenfield M, Aggarwala KR, Raul C, Ciuffreda KJ.

Source

SUNY/State College of Optometry, Dept. of Vision Sciences, NY 10010.

Abstract

Vague and conflicting suggestions currently exist within the literature regarding the appropriate level of ambient illumination to use while conducting the clinical duochrome (bichrome) test. One proposal is that reduced illumination should be adopted since this allows the pupils to dilate, thereby increasing the chromatic interval and resultant test sensitivity. The aim of the present study was to determine whether changes in pupil size and ambient illumination do indeed alter the subjective duochrome response. Accordingly, eight young, visually normal subjects were dilated with 2.5 percent phenylephrine and tested while monocularly viewing the duochrome chart through 1, 3, 5 and 7mm artificial pupils. Additionally, the effects of performing the test through a 1.0 log unit neutral density filter and varying the overall room illumination were examined. There were no significant differences between the mean responses under all test conditions. The variability of individual responses decreased with increasing pupil size; however, a 4mm change in pupil diameter was required to alter the response variability significantly. Therefore it is recommended that the test be performed under the minimum practical ambient illumination conditions in order to minimize this variability.