System for psychophysical measurements of two-photon vision


  • Agnieszka Zielińska
  • Karolina Kiluk
  • Maciej Wojtkowski
  • Katarzyna Komar



Two-photon absorption occurring in photoreceptors of human eye is responsible for perception of pulsed infrared laser beams. Color of perceived light corresponds to about half of wavelength of stimulating beam. This recently discovered phenomenon is called two-photon vision. However it is yet not clear how such phenomena could impact an ophthalmic diagnosis and therefore further studies are required. In this paper we present the system that enables future psychophysical experiments to extend knowledge about two-photon vision and its diagnostic value by identifying differences between two-photon and single-photon vision.

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How to Cite

A. Zielińska, K. Kiluk, M. Wojtkowski, and K. Komar, “System for psychophysical measurements of two-photon vision”, Photonics Lett. Pol., vol. 11, no. 1, pp. 1–3, Apr. 2019.