In recent years, the use of 3C electronic products is very popular, but the light emitted by these products' screens contains a lot of harmful blue light, which is an important source of "Light Pollution" today. With the increasing incidence of myopia, people pay more attention to the protection of vision.
According to the suggestions of ophthalmologists and optical experts, the high-quality LED light source which can achieve the effect of protecting eyesight without harming eyesight should have the following eight characteristics: Filtering harmful blue light, No glare, No ghost, No flickering radiation, No ultraviolet radiation, Uniform illumination, high Color rendering index and Color temperature not over 4000K.
1.Filtering harmful blue light
Blue light, is with a wavelength of 400-500 nm, also known as high-energy visible light.
According to the light-emitting principle of LED, there is inevitably blue light in LED lighting products, but excessive blue light will cause "blue light hazard" to the eyes, visual fatigue, affecting learning and work; leading to macular lesions, causing myopia and cataract; inhibiting the secretion of melatonin will lead to a decline in sleep quality and difficulty in fall asleep.
Glare can be divided into direct glare and reflective glare (commonly known as reflective glare). Direct glare, within 30-60 seconds, will cause obvious visual impairment. Reflective glare will blur the image, fatigue the eyes, cause reading hard, and further cause eyeache and headache. If the light shielding of the lamps is not good, it will cause glare effect.
Ghosting, the main symptom is that an object is seen as two objects. Some patients are unable to describe true diplopia, but feel blurred vision or have difficulty seeing in a particular direction. Some patients have dizziness, headache, nausea, crooked head and other symptoms.
Flicker is the phenomenon that the intensity of light source varies with time, and the amplitude and frequency of stroboscopic change with time. The flicker of bad light source can cause headache, eye fatigue, restlessness, or epilepsy.
5.No ultraviolet radiation
The high-color temperature light of traditional fluorescent lamp contains ultraviolet, which can affect the oxygen reduction process of lens of human eye, promote the degeneration of lens of human eyes, cause cataract and macular degeneration. It can also penetrate into the dermis, causing aging and crepe, and susceptible to skin cancer.
Illumination uniformity, refers to the ratio of minimum illumination to average illumination on a specified surface. The more uniform the light distribution, the better the illumination, the more comfortable the visual feeling.
7.Color rendering index>80
CRI is the measure degree of color conformity of an object when illuminated by this light source and by a standard light source (usually using sunlight as the standard light source), i.e. the degree of color fidelity.
8.Color temperature ≦4000k
Color temperature is a unit that indicating the color of black body radiation and also represent the color that involve in light. When the light present orange-yellow color, make people drowsy. When the light present blue-white color, will feel dazzling and uncomfortable.