SYSTEM AND METHOD FOR MEASURING PHYSICAL, CHEMICAL AND BIOLOGICAL STIMULI USING VERTICAL CAVITY SURFACE EMITTING LASERS WITH INTEGRATED TUNER

摘要

An optical sensor diagnostic system utilizes a tunable Vertical Cavity Surface Emitting Laser (VCSEL) that incorporates an integrated MEMS tuning mechanism provides variable wavelength light into an optical fiber with improved wavelength scanning speed and greater simplicity of construction. Sensors, such as Bragg gratings, are disposed along the fiber in the light path. Each sensor reflects or transmits light exhibiting a characteristic amplitude and/or phase feature with respect to wavelength, the wavelength position of which is affected by an environmental stimulus imposed thereon. The light reflected or transmitted through each sensor is mixed with light passed through an optical reference path and then converted to an electrical signal by a simple detector and monitored by circuitry that applies signal processing to the detected power spectral distribution, by this means providing output signals indicative of the environmental stimulus on each sensor.