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Direct detection of a single photon by humans.

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 the eye can be perceived by a human subject has remained a fundamental open question. Here we report that humans can detect a single-photon incident on the cornea with a probability significantly above chance. This was achieved by implementing a combination of a psychophysics procedure with a quantum light source that can generate single-photon states of light. We further discover that the probability of reporting a single photon is modulated by the presence of an earlier photon, suggesting a priming process that temporarily enhances the effective gain of the visual system on the timescale of seconds.

SUBMITTER: Tinsley JN

PROVIDER: S-EPMC4960318 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Direct detection of a single photon by humans.

Tinsley Jonathan N JN Molodtsov Maxim I MI Prevedel Robert R Wartmann David D Espigulé-Pons Jofre J Lauwers Mattias M Vaziri Alipasha A

Nature communications 20160719

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 the eye can be perceived by a human subject has remained a fundamental open question. Here we report that humans can detect a single-photon incident on the cornea with a probability significantly above chance. This was achieved by implementing a combination of a psychophysics procedure with a quantum light source tha ...[more]

PMID: 27434854

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