| abstract |
An optical sensor diagnostic system uses a tunable Vertical Cavity Surface Emitting Laser (VCSEL) that incorporates an integrated MEMS tuning mechanism. The system provide 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 feature with respect to wavelength, the wavelength position of which is affected by an environmental stimulus imposed thereon. The reflected light is converted to an electrical signal by a simple detector and monitored by circuitry that detects changes. The system provides output signals indicative of the environmental stimulus for each sensor. |