目的 比较光纤耦合与透镜耦合技术的光传输效率，以了解其在透射电镜成像装置设计中的应用特点。方法 用两个相同型号的数码相机分别以光纤耦合和透镜耦合技术拍摄相同视野、相同照度的物面，计算图像像素的平均值，以相同输出（像素的平均值）所需要的曝光时间来衡量他们的光传输效率。结果 光圈F/4的透镜耦合装置拍摄照度为37.8 lux的均匀物面，曝光时间为240 ms时所得图像像素的平均值为19623；而相同的曝光量（像素平均值）条件下，光纤耦合装置的曝光时间为15.49 ms。结论 图像像素的平均值为19623时，光纤耦合的光传输效率更高，约为光圈F/4的透镜耦合的15.49倍。

Objective Comparing the light transmission efficiency between fiber optic coupling and lens coupling to understand their application characteristics in the design of imaging device for transmission electron microscope. Methods One digital camera which had integrated fiber optic coupling technology and another digital camera which had integrated lens coupling technology were used in shooting an object plane with the same visual field and luminance. Then the average pixel values of the images obtained through fiber optic coupling technology and lens coupling technology were calculated. Based on the condition of the same average pixel value of the images, the exposure time of fiber optic coupling technology and that of lens coupling technology were compared to evaluate their light transmission efficiencies. Results When the average pixel value of the images obtained though the two technologies with the object plane luminance of 37.8 lux is 19623, the exposure time of lens coupling device with F/4 diaphragm is 240 ms while that of fiber optic coupling device is 15.49 ms. Conclusion When the average pixel value of the images is 19623, the light transmission efficiency of fiber optic coupling technology is higher, which is 15.49 times as high as that of lens coupling technology.