方法：招募健康男性志愿者10名10眼作为受试者，以右眼为测试眼，利用视觉监视系统设置不同环境亮度并附加眩光，测量自然、3.0mm和5.0mm瞳孔时的CSF； 利用视觉质量分析仪测量3.0mm和5.0mm瞳孔时的调制传递函数(MTF)，根据CSF与MTF的比值求得NCSF。

结果：NCSF和CSF随环境亮度降低曲线整体下移，波峰向低频区移动，CSF更偏向低频区。CSF变化受NCSF和MTF共同作用，瞳孔开大，MTF下降，在明视觉环境和中间视觉环境中，NCSF和CSF上升，主要上升区为中低频区； 当亮度较高或存在眩光源时，NCSF和CSF在中低频区上升不明显，在高频区有下降的趋势； 在暗视觉环境中，小范围的瞳孔波动对NCSF和CSF没有显著影响。

结论：NCSF能够反映视觉神经系统的功能，与MTF共同决定CSF。CSF曲线形状与NCSF相近，波峰更偏向低频区。环境亮度降低会使NCSF下降，CSF随之下降； 瞳孔开大会使NCSF在中低频区上升，CSF随之上升，而环境较亮或存在眩光源时，NCSF和CSF在高频区都有下降的趋势。

METHODS: Ten healthy male volunteers(10 eyes)were recruited in this study, and the right eye was tested in this experiment. Different surround luminance levels and glare were set by Vision Monitor System to measure CSF curves of normal pupil, 3.0mm pupil and 5.0mm pupil. Modulation transfer function(MTF)curves of 3.0mm pupil and 5.0mm pupil were measured by Optical Quality Analysis System. NCSF was the ratio of CSF and MTF.

RESULTS:NCSF and CSF curves went downward considerably and the curve waves shifted towards low spatial frequency as the surround luminance decreases. Compared with NCSF, the curve waves of CSF shifted towards lower spatial frequency. The change of CSF was affected by NCSF and MTF. When pupil diameter increases, MTF curve went downward. While the NCSF and CSF curves mounted up at low spatial frequency in the mesopic and photopic visual environment and showed downward trend at high spatial frequency in excessive bright environment or with glare. In the scotopic visual environment, the slight pupil diameter change cannot considerably affect CSF and NCSF curves.

CONCLUSION:CSF is influenced by MTF and NCSF which reflects the function of the retina-brain neural system. The curve shape of CSF is similar to NCSF, but the curve wave is at lower spatial frequency. NCSF and CSF curves go downward as the surround luminance decreases. As the pupil diameter increases, NCSF and CSF curves mount up at low spatial frequency but show downward trend at high spatial frequency in excessive bright environment or with glare.