Blue Light

Blue

Blue is one of the three primary colours in the RGB (additive) colour model, as well as in the RYB colour model. It lies between violet and cyan on the spectrum of visible light. The term blue generally describes colours perceived by humans observing light with a dominant wavelength between approximately 450 and 495 nanometres. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering. An optical effect called the Tyndall effect explains blue eyes. Distant objects appear more blue because of another optical effect called aerial perspective.

Blue laser

A blue laser emits electromagnetic radiation with a wavelength between 400 and 500 nanometers, which the human eye sees in the visible spectrum as blue or violet.

Blue Light (unit)

Blue Light was a United States Army counter-terrorist subunit of the 5th Special Forces Group that existed in the late 1970s. It was founded in 1977 to fill the capabilities gap in counter-terrorism operations while Delta Force became operational.

Light

Light, visible light, or visible radiation is electromagnetic radiation that can be perceived by the human eye. Visible light spans the visible spectrum and is usually defined as having wavelengths in the range of 400–700 nanometers (nm), corresponding to frequencies of 750–420 terahertz. The visible band sits adjacent to the infrared and the ultraviolet, called collectively optical radiation.

blue light

Noun

1. A mixture of chemicals (including nitre, sulfur and antimony) used in the eighteenth and nineteenth centuries for night-time signaling and general illumination. .mw-parser-output .defdate{font-size:smaller}
2. A New England federalist, who opposed the Anglo-American War of 1812; , a federalist.

Verb

1. To travel quickly in a police or ambulance vehicle with the lightbar (and possibly the siren) activated.