The Fiber Optic pH Sensor system consists of a optical fiber probe designed to hold immobilized colorimetric indicator dye materials, plus a light source, spectrometer manufacturer and OOISensors Professional software. You can supply your own indicator material, or select from our line of transparent or reflective professional films. Calibration involves recording spectra in high and low pH samples, and in at least one pH standard such as a NIST-traceable buffer.