Abstract: A chemometric analyzer for analyzing a plurality of analytes. The analyzer disperses radiation by wavelength along an encoding axis. The analyzer includes a spatial radiation modulator having a plurality of radiation filters. Each radiation filter modulates the intensity of a corresponding spectral component in the radiation.

Abstract: Apparatus and method for measuring the absorbance of fluid samples. The length of the light path through the sample is adjusted to optimize the amount of light absorbed by the sample, and the absorbance of the sample is calculated from the length of the path and the amount of light absorbed. Accurate measurement of the absorbance of the fluid may be made by taking measurements at two different path lengths, since light level changes due to fouling of the optical windows or other slow changes in the optical train are independent of the path length, while that of the fluid varies proportionally with the path length. A preferred form of probe includes a cylindrical cell having an exposed variable path length sensing portion at one end and an actuator for varying the spacing at the other end, and a cylindrical cell insertion tube having seals and a large valve mechanism to permit removal of the probe without loss or escape of the fluid being measured.

Abstract: System and method for analyzing spectral data from an optical fiber waveguide. Light from the waveguide is directed to a diffraction grating which separates the light into its spectral components and directs these components toward a light responsive detector. The grating is rotated to cause spectral components of different wavelengths to sweep across the detector, and a sensor provides a signal corresponding to the angular position of the grating. A table of calibration data is generated by introducing monochromatic light of known wavelength into the waveguide, positioning the grating to cause the light at two known points in the spectrum of the monochromatic light to impinge upon the detector, and utilizing the wavelength of the monochromatic light and the values of the sensor signal at the two known points to define the relationship between the sensor signal and the detected wavelength for a plurality of grating positions.