Visible spectrum
The visible spectrum, also known as the visual spectrum or visual wavelength, is a term in physics for describing the portion of electromagnetic radiation detectable to an eye or sensors. 

In 2154, during his time as a prisoner of Starfleet, Doctor Arik Soong wrote down his ideas on paper describing the ways he would change the DNA sequence of Humans. One of his ideas would have resulted in Humans seeing an increase in their ability for perceiving the visual spectrum by five percent. ()

For the creatures of Tarchannen III, their visual spectrum did not extend to the ultraviolet. Using ultraviolet light, which did not frighten them, an away team from the  in 2367 located Geordi La Forge, who had been transforming into one of these creatures, and transported him back safely to the starship where he was successfully treated. ()

In 2367, a Federation shuttlecraft conducted a short range scan of an alien probe. Starting  the scan with a passive high-resolution series in the electromagnetic band, the shuttle was only able to pick up visual wavelengths from 4500 to 7000 Ångströms. ()

The s had an enormous visible spectrum, with it extending to 74,000 nanometers. In 3189, Linus, a Saurian crewmember aboard the , confirmed this fact in response to a statement about it from . ()

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Physics