Abstract: In order to achieve low illumination detection, a day and night compatible photoelectric scope is designed based on the electron bombarded active pixel sensor(EBAPS) of Northern Night Vision Co. Ltd. First of all, analyze the imaging characteristics of the EBAPS sensor, combine the characteristics of the night-mode split-focus surface of the sensor, and select the refractive initial structure to meet the imaging requirements of the device's split-focus surface by mechanical focusing. Use the CODE V optical design software to optimize the image quality of the EBAPS objective lens optical system, and achieve 0.3 mm focal separation in day and night mode by changing the glass air gap. The objective lens system's field of view angle is 10°×8.2°, the F number is 1.3, and the spectral range covers 450 to 10. 00 nm, the clear imaging range is from 5 m to infinity. At the same time, an eyepiece with a ±5D visual degree adjustment range is designed, with an OLED micro-display. The whole photoelectric scope meets the recognition distance of not less than 300m for people walking upright in 10^-3lx illumination space.