Automated method for wavelength estimation in a two-beam interferometer based on the on–off switching of two laser-diode sources

In this manuscript a method is proposed to estimate the wavelength of a laser diode source, under the scheme of a two-source Twyman–Green interferometric setup. This proposal is based on the count and ratio of the interfering fringes generated by two laser diode sources with a standard and unknown wavelength when they are independently switched on–off. The viability of the proposed experimental setup allows it to be easily replicated and used for research or teaching purposes, where special topics in optics for undergraduate or graduate students are required.