Photoreceptors initiate vision by converting photons to electrical activity. The onset of the phototransduction cascade is marked by the isomerization of photopigments upon light capture. We revealed that the onset of phototransduction is accompanied by a rapid (<5 ms), nanometer-scale electromechanical deformation in individual human cone photoreceptors. Characterizing this biophysical phenomenon associated with phototransduction in vivo was enabled by high-speed phase-resolved optical coherence tomography in a line-field configuration that allowed sufficient spatiotemporal resolution to visualize the nanometer/millisecond-scale light-induced shape change in photoreceptors. The deformation was explained as the optical manifestation of electrical activity, caused due to rapid charge displacement following isomerization, resulting in changes of electrical potential and surface tension within the photoreceptor disc membranes. These all-optical recordings of light-induced activity in the human retina constitute an optoretinogram and hold remarkable potential to reveal the biophysical correlates of neural activity in health and disease.

感光器通过将光子转换为电活动来启动视觉。光转导级联的开始以光捕获后光色素的异构化为标志。我们发现，光转导的开始伴随着单个人体视锥细胞感光器中的快速（<5 ms）纳米级机电变形。通过线场配置中的高速相位分辨光学相干断层扫描能够表征与体内光转导相关的这种生物物理现象，该配置允许足够的时空分辨率来可视化光感受器中纳米/毫秒级的光诱导形状变化。变形被解释为电活动的光学表现，这是由于异构化后的快速电荷位移引起的，导致感光盘膜内电位和表面张力的变化。这些人类视网膜中光诱导活动的全光学记录构成了视光图，并具有揭示健康和疾病中神经活动的生物物理相关性的显着潜力。