Low refractive index photocureable coating

The invention discloses a low refractive index photocureable coating, which comprises oligomers, reactive diluents, heat stabilizers and photoinitiators; and because of the chemical inertnesses, hydrophobicities and special internal lubricities of silicon and fluorine, the friction coefficient of the photocureable coating in the invention is small, thereby facilitating the quick production of an optical fiber. The photocureable coating disclosed by the invention is characterized in that the photocureable coating is low in refractive index, when the photocureable coating is used as the coating of the external layer of the optical fiber, in cooperation with the internal layer of the optical fiber with high refractive index, so that the lossless transmission of optical signals can be realized theoretically; the cured coating is excellent in optical fiber protection performance; the coating is good in flexibility and high/low temperature performance; the optical fiber is good in slight-bend resistance, thereby reducing the information loss of the optical fiber; when independently being used as the inner coating of the optical fiber, the photocureable coating has the advantages of good optical-fiber adhesion and appropriate strippable property, thereby benefiting the repair of a fractured optical fiber; and after the coating on the external layer of the optical fiber is cured, the external coating of the optical fiber has the characteristics of good mechanical strength, high hydrolytic resistance, chemical corrosion resistance and thermal stability.