为了降低双目瞳孔检测系统放大率对瞳孔位置的敏感性, 设计了一款基于近红外远心镜头的双目瞳孔检测仪。阐述了系统中的核心部件——近红外远心镜头光学参数的计算过程, 分前后组进行设计, 并运用Zemax完成光学系统优化, 以全视场MTF、全视场最大畸变和物方远心度为指标对系统进行公差分析, 利用标准圆对仪器进行标定, 拟合出像素数和瞳孔大小的对应关系。结果表明, 对于55 mm~75 mm的瞳距, 瞳孔的直径测量精度可达0.05 mm, 满足使用要求。

In order to reduce sensitivity of binocular pupil detection system to the pupil position, a binocular pupil detector based on near-infrared telecentric lens is designed. Calculation process of optical parameters of near-infrared telecentric lens is described. Telecentric lens is designed and optimized in different parts with Zemax.Tolerance is analyzed by MTF, maximum distortion of the whole field and object telecentricity. Finally, standard circle is used to calibrate the instrument to find out fitting correspondence between number of pixels and pupil size. Results show that pupil diameter measurement accuracy reaches 0.05 mm for interpupillary distance of 55 mm to 75 mm, which can meet the requirements.