EC Ophthalmology

The article analyzed the factors induced myopia: inheritance and environment.

Flicker in the Environmental effect is the dominant factor. Flicker will cause eyestrain, long term eyestrain will cause the ciliary muscle to contract and never relax, then the lens shape becomes rounder and cannot focus the distant object on the retina. The myopia is induced.

Percent flicker and flicker index are used to measure the flicker.

When percent flicker and flicker index are smaller, the flicker is smaller, then the flicker above the retina comfortable level is smaller, the accumulated uncomfortable light energy needs more time to reach the pupil shut threshold, the pupils dilate and contract less, so the eyestrain is reduced.

Current lamp manufacture did not remove flicker but tried to increase the flicker frequency to kilohertz and above in order to fool the eye not to sense the flicker. The analysis proves high frequency flicker does not reduce the eyestrain.

For best lamp, we need the lamp absolutely flicker free that is Percent flicker = 0% and Flicker Index = 0. Spectrum of the light is also related to eyes health, analysis is done to show the spectral components’ impact.

 Keywords: Myopia; Lamp; Vision; Percent Flicker; Flicker Index

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