Peripheral Light Focusing (PLF) can be described as the focusing of Solar
Ultraviolet
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiati ...
Radiation (SUVR) at the
nasal limbus of the
cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical ...
. SUVR incident at the temporal limbus passes across the corneal dome and focuses at the nasal limbus. The limbal region is a
stem cell
In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can differentiate into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of ...
rich tissue. Ocular conditions such as
pinguecula and
pterygium
Pterygium (plural ''pterygia'' or ''pterygiums'') refers to any wing-like triangular membrane occurring in the neck, eyes, knees, elbows, ankles or digits.
The term comes from the Greek word ''pterygion'' meaning "wing".
Types
* Popliteal pter ...
may occur due to the result of this increased exposure to SUVR in limal area, but it is not the only cause of pterygium formation.
References
Eye
{{eye-stub