The infrared rays is a kind of electromagnetic wave . - Its wavelength is 0.76 - 1000¥ì. Like X - rays, UV rays, and microwave rays, infrared rays are invisible. They cannot be seen by the naked eye .
    These rays were discovered in 1800 by William Herschel, a British musician and astronomer, when he observed that a thermometer placed just outside the visible spectrum of sunlight shows a greater increase in temperature than one placed in the red region. In accordance with wavelength, near infrared rays is from 0.76¥ìto 1.5¥ì, middle infrared rays is from 1.5¥ìto 5.6¥ì.And far infrared rays is from 5.6¥ìto 1000¥ì. - The most useful far infrared rays for our body is in 6¡­14¥ì.Infrared rays have the trait of all ray, so usually be used as close quarters communication carrier wave, the typical use of it is the remote controller of TV.