Laser wavelength and eye injury: among laser injuries, the eye injury in the body is the most serious. For lasers with wavelengths in visible light and near infrared light, the refractive medium of the eye has low absorption rate and high transmittance, while the focusing ability (that is, light focusing ability) of the refractive medium is strong.

When high-intensity visible light or near-infrared light enters the eye, it can pass through the refractive medium of the human eye and accumulate light on the retina. At this time, the laser energy density and power density on the retina increased to thousands or even tens of thousands of times, and a large amount of light energy was instantly concentrated on the retina, which caused the temperature of the photosensitive layer of the retina to rise rapidly, causing the photosensitive cells to solidify, denature and die, losing their photosensitive function.

When laser is focused on photosensitive cells, protein coagulation and denaturation caused by overheating is irreversible damage. Once damaged, it will cause permanent blindness in the eyes.

Extended data:

Laser has strong focusing ability, strong directivity and concentrated beam. When the child's eyes look directly at the laser emitted by the laser pointer, it may be irreparable because of the delicate eye tissue of the child.

Li Shuangle, director of ophthalmology in a hospital in Zigong, said in an interview with Huaxi Daily that direct laser irradiation on the eyes may cause damage to the retina and macula, which directly leads to decreased vision. The more serious consequence is that after the macula of the eye is damaged, it will cause permanent damage to the eye.

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