紅外线和我們看得見的光线一样,都是电磁波,不同的是紅外綫的波长較可見光的波长要长一些,人們的眼睛看不見它們。一个正常人的眼睛所看到的光的波长大約在0.4微米到0.75微米之間(1微米等于1毫米的千分之一),电磁波譜的这个区域被称为可見光区。电磁波的波长从0.75微米一直到1000微米的范围,就是紅外线区 Infrared and we can see the same light, are electromagnetic waves, the difference is that the wavelength of infrared light longer than the wavelength of visible light, people’s eyes can not see them. The wavelength of light seen by a normal human eye is between about 0.4 and 0.75 microns (1 micron equals one thousandth of a millimeter) and this region of the electromagnetic spectrum is called the visible region. The wavelength of electromagnetic wave from 0.75 microns to 1000 microns range, is the infrared region