激发光引起的荧光漂白限制了共聚焦成像技术在长时间观测生物样本方面的应用。提出了一种基于可控光剂量的共聚焦成像技术(CLE-CM)，该技术通过预实验设置高低阈值，定时读取采样像素值并与预设阈值进行比较，根据比较结果控制每个物方像素的光照时间，以更高效地利用荧光信息，在不牺牲图像质量的情况下降低了荧光漂白。用CLE-CM和标准共聚焦对牛肺动脉内皮细胞样本连续成11幅图像，与第11幅标准共聚焦图像相比，第11幅CLE-CM图像的荧光漂白减少了52.62%，具体降漂白效果与样本中的荧光分布有关。CLE-CM通过减少光剂量大幅降低了共聚焦显微成像的荧光漂白，使共聚焦显微镜能连续成更多张高质量图像。

Photobleaching induced by excitation light limits the application of confocal microscopy for long-time observation of biological samples. A new imaging approach, controllable light exposure-confocal microscopy (CLE-CM), is proposed. CLE-CM has two thresholds decided through pre-experiments and detects the feedback of sample pixel value at set intervals. The feedback is compared with upper and lower thresholds. By spatially controlling the light-exposure time of objective pixel according to the results of comparison, CLE-CM exploits fluorescent information in a more efficient way and reduces photobleaching without decreasing image quality. Two scan series of 11 successive CLE-CM images and standard confocal images show that, CLE-CM reduces 52.62% of photobleaching in bovine pulmonary artery endothelial (BPAE) cells compared with standard confocal at the 11th image. The effect of bleaching attenuation depends on the fluorophore distribution. CLE-CM decreases photobleaching markedly through the reduction of excitation-light dose, and increases the number of good-quality images that can be captured continuously by confocal microscope.