Direct detection of a single photon by humans

• DOI: 10.1038/ncomms12172
• Publication Date: 2016-07-19T14:58:29Z
• Authors: Jonathan N. Tinsley; Maxim I. Molodtsov; Robert Prevedel; David Wartmann; Jofre Espigulé-Pons; Mattias Lauwers; Alipasha Vaziri
• Keywords: Two-photon excitation microscopy

Abstract Despite investigations for over 70 years, the absolute limits of human vision have remained unclear. Rod cells respond to individual photons, yet whether a single-photon incident on eye can be perceived by subject has fundamental open question. Here we report that humans detect cornea with probability significantly above chance. This was achieved implementing combination psychophysics procedure quantum light source generate states light. We further discover reporting single photon is modulated presence an earlier photon, suggesting priming process temporarily enhances effective gain visual system timescale seconds.