Title :
Development of medical pressure and temperature sensors employing optical spectrum modulation
Author :
Wolthuis, Roger A. ; Mitchell, Gordon L. ; Saaski, Elric ; Hartl, James C. ; Afromowitz, Martin A.
Author_Institution :
MetriCor Inc., Woodinville, WA, USA
Abstract :
Fiber optic Fabry-Perot sensors have been developed whose optical reflectance varies with optical cavity depth (pressure) or with change in a material´s refractive index (temperature). These sensors employ a unique combination of features: they are interrogated by an LED; they are designed to operate within a single reflectance cycle; and their returned light is analyzed by a dichroic ratio technique. The sensors use a step index glass fiber and are relatively insensitive to absolute light levels and fiber bending. They have an expanded linear operating range and can be built for low cost disposable applications. Sensor performance meets or exceeds established medical requirements.
Keywords :
biomechanics; biomedical equipment; biothermics; fibre optic sensors; pressure transducers; spectral methods of temperature measurement; LED; absolute light levels; dichroic ratio technique; expanded linear operating range; fiber bending; fiber optic Fabry-Perot sensors; low cost disposable applications; medical instrumentation; optical cavity depth; optical spectrum modulation; reflectance cycle; refractive index; returned light; sensor performance; step index glass fiber; Biomedical optical imaging; Fabry-Perot; Optical fiber sensors; Optical fibers; Optical modulation; Optical refraction; Optical sensors; Optical variables control; Reflectivity; Temperature sensors; Blood Pressure Determination; Equipment Design; Fiber Optics; Interferometry; Thermometers;
Journal_Title :
Biomedical Engineering, IEEE Transactions on