PERFORMANCE OF A COMPACT, HYBRID OPTICAL EVANESCENT-WAVE SENSOR FOR CHEMICAL AND BIOLOGICAL APPLICATIONS

We describe a hybrid evanescent-wave sensor component that we fabricat ed by using an integrated optical interferometer with a specially adap ted photodetector array. The design of the interferometer is based on the use of tapered waveguides to obtain two intersecting collimated be ams. Phase shifts can be measured with an angular precision of better than 10(-3) rad, which corresponds to a superstrate index change infer ior of 10(-6) with our structure. The interest in the device as a chem ical sensor is experimentally demonstrated. The same optical component could be used in a variety of other sensor applications, e.g., biolog ical and immunological sensors. (C) 1996 Optical Society of America