what produces visible light
The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye.Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 700 nm.In terms of frequency, this corresponds to a band in the vicinity of 430â770 THz.isible wavelengths pass through the  optical window , the region of the electromagnetic spectrum that allows wavelengths to pass largely unattenuated through the Earth's atmosphere. An example of this phenomenon is that clean air scatters blue light more than red wavelengths, and so the midday sky appears blue.