摘要
给出了一种新型眼底相机照明系统的设计方案。针对现行眼底相机照明系统复杂的问题,对经典的柯勒照明光路进行改良设计,得到了一个结构简单的眼底照明系统。结构中除网膜物镜外,只需用到4片透镜,且眼底照明区域直径连续可调,充分利用了光能。通过在照明光路中添加黑点板和环形光阑,屏蔽了系统99%以上的杂散光,使眼底相机成像画面的信噪比达到20dB以上,提高了对比度。同时在Gullstrand_Le标准眼模型上,得到一个均匀度达95%以上的照明区域。
A new design of illuminating system used in fundus cameras was proposed. The design was a improved system based upon Kohler illumination, and it used the near infrared light which could not be felt by human eye to deal with the problem of iris shrinking effect when illuminating light flashed. The design had only four lenses and the illuminated area could be adjust continuously, meanwhile the energy of the illumination light could be used efficiently. By inserting black dot boards and a ring stop in the light, the design could shield almost 99% stray light, and the Ratio of Signal to Noise（S/N） of the system could be up to 20 dB. The Gullstrand_Le standard eye model was used in the system, and a uniform illuminated area with the uniformity of 95% could be achieved.
出处
《中国光学与应用光学》
2010年第4期363-368,共6页
Chinese Optics and Applied Optics Abstracts
基金
国家863高技术研究发展计划资助项目(No.2007AA12Z110)
国家自然科学基金资助项目(No.60507003)
关键词
眼底照相机
柯勒照明
眼模型
信噪比(S/N)
均匀度
fundus camera
Kohler illumination
eye model
Ratio of Signal to Noise （S/N）
uniformity
