Method of incorporating vertical cavity surface emitting lasers in an

Abstract

A method of transmitting the output signal from each pixel of an array of vertical cavity surface emitting lasers (VCSEL's) operatively positioned in an acoustic detector which minimizes the size of interconnects to the different pixels, which uses optical fibers to transport the output signal from each VCSEL pixel to the signal processing assembly. The VCSEL array is fabricated onto an acoustic matching layer which is designed to allow maximum acoustic coupling into the transducer assembly. An acoustic damping layer is employed after the array in order to extinguish the acoustic energy in order to avoid reflections within the transducer. Alternatively, an acoustic reflecting layer can be employed depending on the sensitivity and bandwidth requirements of the application. The frequency modulation of the laser output caused by the acoustic disturbance is then converted into amplitude modulation in a Fabry-Perot cavity array attached to the damping layer. This cavity could also employ a spatial light modulator array or some other tuning element array which would allow feedback to correct for any laser fluctuations at frequencies lower than the acoustic frequency. Finally, an array of fiber optic couplers would couple the amplitude modulated signal to a signal processing assembly.