Method for detecting laser wavelength by Goos-Hanchen displacement characteristic

A method for detecting laser wavelength by Goos-Hanchen shift characteristic belongs to the technical field of precision measurement. In the method, a laser beam having a divergence angle smaller than 0.4mrad is emitted on a double metal-cladding waveguide structure which consists of a metal film deposited on a prism, an air gap and a metal film deposited on optical glass. When a coupling condition is satisfied, the laser enters the waveguide. The reflected light generates an absorption peak, and phase of the reflected light rapidly changes relatively to the phase of incident light so that the Goos-Hanchen shift of the reflected light is greatly increased; and the wavelength of a wave output by the laser is measured by detecting the Goos-Hanchen shift of the reflected light according to the characteristic that the Goos-Hanchen shift is extremely sensitive to the wavelength change of the incident laser. The supersensitive, fast and accurate real-time measurement can be achieved by the method, and the measurement method is simple, has strong anti-interference capability, and can be widely applied to the aspects such as wavelength resolution and shift suppression of laser output waves in a dense wavelength division multiplexing system and the like.