| abstract |
A chemical sensor, such as a fiber optic chemical sensor, is self-calibrating by measuring two output values that behave differently in response to an analyte, and by relating the two measured output values to cancel out the effects. variations in external factors such as temperature variations, differences between coatings, variations in light (light source), adsorption of dyes, bleaching, leaching or the like. An indicator material can be used which produces fluorescence and phosphorescence, absorption or emission bands of monomer and aggregate, emission or absorption bands with or without an isobestic point, peaks emission at one wavelength at two different excitation bands, or emission peaks at two wavelengths for excitation at two wavelengths. |