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What happens to rhodopsin in bright light?

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details of the mammalian eye — Photoreception The mammalian eye has a cornea and a lens and functions as a dioptric system, in which light rays are refracted to focus on the retina.

When exposed to bright light, the rhodopsin molecule undergoes a process known as bleaching.1

Structurally, rhodopsin consists of a protein called opsin and a pigmented molecule called 11-cis-retinal. When light strikes the retina, the 11-cis-retinal is converted into all-trans-retinal, which triggers a change in the configuration of the rhodopsin molecule. This change initiates a phototransduction cascade that converts light into an electrical signal sent to the brain.1

Following this configuration change, the opsin dissociates from the retinal, causing the pigment to fade from its characteristic reddish-purple color to a pale state. This bleaching process decreases the sensitivity of the rod cells to light, which prevents them from being overstimulated in bright environments and allows cone cells to take over visual processing. The rhodopsin is later regenerated in the dark through a recycling process that recombines retinal with opsin.12