| Autor: |
Doyle HK; Department of Electrical Engineering and Computer Sciences, University of California Berkeley, Berkeley, CA, USA.; hannahdoyle@berkeley.edu., Herbeck SR; Department of Electrical Engineering and Computer Sciences, University of California Berkeley, Berkeley, CA, USA.; sofieherbeck@berkeley.edu., Boehm AE; Herbert Wertheim School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, USA.; aeboehm@berkeley.edu., Vanston JE; Herbert Wertheim School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, USA.; jvanston1206@gmail.com., Ng R; Department of Electrical Engineering and Computer Sciences, University of California Berkeley, Berkeley, CA, USA.; ren@berkeley.edu., Tuten WS; Herbert Wertheim School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, USA.; wtuten@berkeley.edu., Roorda A; Herbert Wertheim School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, USA.; aroorda@berkeley.edu. |
| Abstrakt: |
The 2-photon effect in vision occurs when two photons of the same wavelength are absorbed by cone photopigment in the retina and create a visual sensation matching the appearance of light close to half their wavelength. This effect is especially salient for infrared light, where humans are mostly insensitive to 1-photon isomerizations and thus any perception is dominated by 2-photon isomerizations. This phenomenon can be made more readily visible using short-pulsed lasers, which increase the likelihood of 2-photon excitation by making photon arrivals at the retina more concentrated in time. Adaptive optics provides another avenue for enhancing the 2-photon effect by focusing light more tightly at the retina, thereby increasing the spatial concentration of incident photons. This article makes three contributions. First, we demonstrate through color-matching experiments that an adaptive optics correction can provide a 25-fold increase in the luminance of the 2-photon effect-a boost equivalent to reducing pulse width by 96%. Second, we provide image-based evidence that the 2-photon effect occurs at the photoreceptor level. Third, we use our results to compute the specifications for a system that could utilize 2-photon vision and adaptive optics to image and stimulate the retina using a single infrared wavelength and reach luminance levels comparable to conventional displays. |
