A technique for wavelength measurement of microwaves is demonstrated. The wavelength is obtained from an interference pattern monitored by an IR Camera. The data captured by the camera is stored in a computer attached to it. This data is then processed for wavelength calculation. In order to show the utility of the above technique, two cases are demonstrated: Case (1) Interference pattern of two patch antennas each radiating at 8 GHz. Case (2) Interference pattern from a single antenna, radiating at 12 Ghz, kept in front of a metallic sheet with two slits. The simulation is carried in CST Microwave Studio software. A good agreement between simulation and experimental results is seen. © 2015 IEEE.