Near infrared (NIR) is an electromagnetic wave between visible light and medium infrared (MIR) light. According to the definition of ASTM (American Society of Testing Materials), it means the electromagnetic wave with a wavelength ranging from 780 to 2526nm. Habitually, NIR is further divided into the two areas of near infrared shortwave (780~1100nm) and near infrared longwave (1100~2526nm). The NIR area is where people discovered invisible light the earliest.
The damage effect on the skin produced by the near infrared light in sunlight is different from that of ultraviolet, which mainly causes photochemical reaction and photoimmunological reaction. However, the reaction resulting the radiation of near infrared light is caused by molecular vibration and temperature rise. The heat radiation caused by near infrared light exceeds ultraviolet in terms of skin penetration. 25%-65% of its radiation can reach the epidermis and corium, while 8%-17% of it can reach the hypoderm. That is to say, the wavelength of NIR is even longer than the UVB in ultraviolet, with a penetration force stronger than that of the UVA in ultraviolet and a dermis-reaching radiation quantity over 3 times that of UVA! It can penetrate the cuticle, epidermis and corium directly to reach the muscles. Likewise, NIR is also harmful for human eyes, as displayed by the following clinical symptoms:
The eyes contain substantial liquid that is strong in the absorption of infrared, while the heat dissipation of the fundus retina is poor to cause the quick local heating thereof, the solar burn in the macular area of the retina and decline of vision. If the damage is serious, it may form perforation and amotio retinae. This typically takes place after observation of eclipse and arclight.
Under the effect of the principle that the shorter the wavelength, the higher the frequency and the greater the energy, the broader the scope that can be penetrated by the light wave, the NIR with a wavelength of <1.5 microns can get into the tissues of human body and the penetration distance can reach 5～10mm. This means that NIR can penetrate the iris to damage it. When human eyes remain exposed to such environment for long, that may give rise to cataract.
The NIR blocking lenses of Sunphey are its latest achievement. As the lenses of the second generation for daily protection, they have the added function of resisting red light in addition to the function of resisting ultraviolet and blue light of the first generation and use nano materials to provide all-round protection for the health of your eyes.
Why should you choose Clear Glass Infrared Block Lens Eyeglass？
- The lenses of Sunphey use the glass of the same quality as that of the original products of world famous brands;
- The lenses use mature and stable coating technology and belong to the small number of products in the market that are manufactured through advanced processes for optical lens grade to ensure perfect binding with the glass materials;
- The lenses of a new generation for daily protection can intercept UV, blue light and infrared for all-round protection;
- The professional vertical customization of glass lenses provides you with the products you need.