Optical refraction

Optical refraction is the change in direction (bending) of light or another wave as it passes from one medium to another with a different optical density[1][3][7]. This phenomenon is governed by Snell’s law, relating the angles of incidence and refraction to the refractive indices of the two media. Refractive index is a fundamental property—defined as the ratio of the speed of light in a vacuum to its speed in the medium—which dictates how much light slows down and bends in passing through substances such as air, water, glass, or biological tissue[1][4][6]. In biological systems, especially in the human eye, refraction is critical for focusing light onto the retina. The cornea and lens serve as the primary refractive surfaces, each with specific refractive indices contributing to the eye’s total optical power[2][4]. Changes or abnormalities in the refractive properties of these tissues underlie common vision disorders such as myopia, hyperopia, and astigmatism[4]. Because optical refraction is not a discrete molecular entity—but a physical principle—it is not classified as a therapeutic target, has no gene/protein structure, no interacting drugs, nor disease mechanisms in the conventional sense. In clinical practice, however, refractive index and light-bending properties of ocular tissues underpin diagnostics and treatment strategies in ophthalmology[4][7]. *Alternative interpretation*: If the query intended to target a specific molecular entity related to refraction (e.g., "Crystallin, lens protein" or "corneal collagen"), please clarify for molecular details. **Summary**: "Optical refraction" is a process, not a molecule, receptor, or drug target. It is essential in understanding vision and optical devices but does not correspond to a druggable biological target.

Other names

Refraction of lightLight refraction