NOVEL FIBER OPTIC CURRENT/VOLTAGE SENSORS FOR SHIPBOARD APPLICATIONS

PHYSICAL OPTICS CORPORATION (POC) PROPOSES TO DEVELOP AND DEMONSTRATE AN IN-LINE FIBER OPTIC VOLTAGE SENSOR THAT MODULATES THE INTENSITY OF THE LIGHT IN A SINGLE-MODE OPTICAL FIBER, VIA A SMALL RUGGED DEVICE THAT IS INTEGRAL TO THE FIBER. THIS ALREADY-PROVEN INTRINSIC FIBER OPTIC SENSOR DESIGN UTILIZES SURFACE PLASMON POLARITON(SPPS), TWO-DIMENSIONAL ELECTROGMAGNETIC WAVES GENERATED AT A METAL-GLASS BOUNDARY BY TAKING ENERGY FROM COHERENT POLARIZED EVANESCENT FIELDS, WHICH OCCUR IN THE CLADDING OF AN OPTICAL FIBER. FOR FABRICATION, THE OUTSIDE OF A SLIGHTLY BENT OPTICAL FIBER IS POLISHED TO A SMALL FLAT REGION, ON WHICH A VERY THIN ((500 ATOMIC LAYERS) METAL FILM IS VACUUM DEPOSITED. THIS CHOICE OF METAL MAY BE IRON FOR A CURRENT SENSOR OR SILVER FOR A VOLTAGE SENSOR. TAILORING OF THE SENSOR RESPONSE FOR A DESIRED OPERATING RANGE IS DONE BY VARYING THE FILM THICKNESS AND ITS LOCATION RELATIVE TO THE FIBER CORE. THERE IS NO CUTTING, SPLICING, OR ANY OTHER FIBER INTERRUPTION INVOLVED. THESE ACCURATE FIBER OPTIC SENSOR DESIGNS HAVE GOOD POTENTIAL TO BE LOW-COST, RUGGED, AND VERSATILE.