Measurement of dissolved oxygen using optical radiation induced luminescence

A dissolved oxygen measurement system comprising:

• a container including an interior to temporarily store liquid for analysis and including an exterior surface, the exterior surface including:
• a first optical window in optical communication with the interior, and
• a second optical window in optical communication with the interior,
• wherein the first optical window is distinct from the second optical window, and
• wherein the first optical window and the second optical window are both transparent or semi-transparent;
• an optical source to emit optical radiation, the optical source located external to the container and positioned to emit the optical radiation through the first optical window and into the interior of the container, and the optical radiation comprising radiation at a wavelength that conforms to an absorption band of, and causes luminescence of, dissolved oxygen, wherein the wavelength is in the infrared spectrum;
• and
• a photodetector located external to the container, the photodetector being in optical communication, via the second optical window, with the liquid in the interior of the container.