Infrared (IR), also known as red light, is an electromagnetic wave whose wavelength is between microwave and visible light. Its wavelength is between 760 nm and 1 mm. It is a non visible light whose wavelength is longer than red light. Most of the thermal radiation emitted by objects at room temperature is in this band. More than half of the energy of the sun enters the earth in the form of infrared rays. Stronger infrared rays can cause skin damage. If the eyes are stimulated by infrared rays too much, the retina inside the eyeballs will be injured. The harm of infrared ray to us is down feeling, photophobia, scorching, cataract , retina peeling off.Infrared light cutting lens is to use technology to change the material characteristics, so that the infrared ray is absorbed or refracted by the lens so that it does not enter the eyes. It can effectively reduce the stimulation of near-infrared radiation on the eyes, reduce the halo under the strong sunlight, and improve the visual clarity.