F-P etalon based on Fresnel diamond prism and design method

The invention provides an F-P etalon based on a Fresnel diamond prism and a design method, and particularly relates to the technical field of testing. An F-P cavity defined by the end faces of the Fresnel rhombus prism is used as an F-P etalon for wavelength locking, a design method of the F-P etalon is provided in a matched mode, the phase difference period of P light and S light in light penetrating through the F-P etalon is determined by obtaining phase delay of total internal reflection of the P light and the S light in the Fresnel rhombus prism, and the wavelength locking precision of the F-P etalon is improved. And the reflectivity and transmittance of a coating film of the F-P etalon are calculated by combining the reflectivity of the incident end face and the emergent end face of the Fresnel rhombus prism and the material absorption loss, so that the Fresnel rhombus prism is transformed into the F-P etalon to replace a double F-P etalon for wavelength locking. The Fresnel rhombic prism is used for rep