Temperture and pressure monitors utilizing interference filters
First Claim
1. Apparatus for measuring a parameter of blood comprising,an optical fiber having at its end an edge filter consisting of alternating metal and dielectric layers, the layers being dimensionally variable in the presence of the blood parameter to be measured,means for launching a polychromatic light into the end of said optical fiber to produce a reflected light having an intensity versus wavelength reflection curve whose transition line shifts with variations in said blood parameter,means for measuring the amount of the shift of the edge of the reflected curve and means for converting the magnitude of said shift to units of said parameter.
1 Assignment
0 Petitions
Accused Products
Abstract
An interference edge filter is mounted on the end of an optical fiber to provide a sensor for pressure or temperature. The filter is formed such that the transition slope of the filter curve will move to the left or right depending upon the changes in the parameter being monitored. The shift in the position of the slope of the edge filter curve is detected by passing the reflected light through an interference bandpass filter having an edge slope intersecting the transition slope and measuring the intensity of the light passing the bandpass filter.
-
Citations
5 Claims
-
1. Apparatus for measuring a parameter of blood comprising,
an optical fiber having at its end an edge filter consisting of alternating metal and dielectric layers, the layers being dimensionally variable in the presence of the blood parameter to be measured, means for launching a polychromatic light into the end of said optical fiber to produce a reflected light having an intensity versus wavelength reflection curve whose transition line shifts with variations in said blood parameter, means for measuring the amount of the shift of the edge of the reflected curve and means for converting the magnitude of said shift to units of said parameter.
-
4. The method of measuring a parameter of blood comprising the steps of
exposing a dimensionally unstable edge filter to the blood, subjecting said filter to polychromatic light to create an intensity versus wavelength curve having a sloping transition line, measuring variations in th position of the transition line of said curve and converting said measured variations to units of said parameter of said blood.
Specification