Structure Analyzing of Orthogonal Two-Wedge Interferometer to Detect Weak Laser Signal

A new strueture of two orthogonal wedge interferometers is proposed by combining the properties of wedge multi-beams interferometers and two-ways detecting systems. All of the components are fixed, and the thickness difference of two interferometers is designed in a fixed value, which could make their fringe patterns have a fixed phase shift of p/2 when laser beams incoming. Two signals were subtracted through a differentiating amplifier. The background noise, which is superimposed on the fringe signals, could be removed and result in higher contrast ratio fringe signals. The proposed structure could be used in detecting weak laser signal in high background noise, and the wavelength of incident laser beams could be calculated simultaneity. The optical parameters were analyzed by computer simulation.