Vision science - driven advanced imaging and display technologies

 The photoreceptors in the human retina are capable of absorbing two photons of the same wavelength simultaneously to create a visual sensation, named "two-photon vision". This sensation matches the appearance of light at approximately half the original wavelength. For instance, the absorption of two infrared photons can generate a visual sensation of green light. Because longer wavelengths (like infrared) are more resistant to scattering, they have the potential to provide alternative vision for individuals with certain eye conditions, such as cataracts. Additionally, light perceived through two-photon vision exhibits higher contrast than conventional single-photon vision, offering unique opportunities to develop modern display technologies based on the two-photon vision principle.