Short communication Two-wavelength contouring with a pulsed ruby laser by employing TV-holography

摘要

A two-wavelength surface contouring system based on electronic speckle pattern interferometry (ESPI) with a pulsed ruby laser is reported. Two states of the test object were recorded at different wavelengths of the laser. The wavelength change was controlled by altering the temperature of the output etalon. The phase information of the surface contour can be obtained by using either the sinusoid fitting method or the Fourier transform method. Contour intervals of about 14 mm and 7 mm are available.