Patent ID: 6943887

Claim:
A surface plasmon sensor comprising: a source of electromagnetic radiation, the electromagnetic radiation having a transverse magnetic component and a transverse electric component; a shield, having an aperture, coupled to receive the electromagnetic radiation to minimize the deviation of the direction of the transmitted electromagnetic radiation from the source; an optical housing, made of material which is capable of transmitting radiation from the source; a film of conductive material capable for sustaining surface plasmon resonance, the film being disposed on an exterior surface of the optical housing, the optical housing and the film being shaped and positioned so that radiation from the source is reflected by the film; a sensor array coupled to receive the reflected radiation, the sensor array, sensitive to the reflected radiation, disposed closely adjacent the surface of the housing; and; a switch disposed between the source and the sensor array to switch between the transverse magnetic component and the transverse electric component of optical radiation such that only one component strikes the sensor array, wherein the transverse electric component of the electromagnetic radiation is utilized to detect optical defects in the surface plasmon sensor.