Method and apparatus for detecting the type of anesthetic gas

An apparatus for detecting a type of anesthetic gas, comprising:

• at least one light source configured for generating a light with a plurality of wavelengths, the light being separated to a plurality of light beams whose central frequencies correspond to the plurality of wavelengths;
• a gas chamber, to which said anesthetic gas is injected, wherein said type of anesthetic gas has an absorption characteristic with respect to one of said plurality of light beams having passed through said gas chamber;
• a detecting unit configured for detecting light intensity of the one of the plurality of light beams transmitted through the gas chamber to obtain a relative absorption coefficient between the one of the plurality of light beams and another light beam of the plurality of light beams, wherein the light beams are absorbed by said anesthetic gas after being injected into the gas chamber;
• and
• a determining unit configured for determining the type of said anesthetic gas based at least in part on the relative absorption coefficient without determining or identifying a concentration of the anesthetic gas.