Abstract: A fluid monitor determines the quality, intensity and/or level of a fluid by transmitting a beam of light through the fluid and evaluating any changes to the shape of the beam as a result of being transmitted through the fluid. The monitor includes a light source and a lens which generate an incident beam of light having a predefined cross sectional shape. The beam is transmitted through a volume of the fluid, which modifies the shape of the beam as a function of the fluid quality, intensity and/or level. The beam can be polarized before being transmitted through the fluid or after beam transmission. The polarized beam is directed to a detector which evaluates the horizontal and vertical components of the beam and provides a shape signal to a detection circuit. The detection circuit processes the shape signal received from the detector to determine the quality, intensity and/or level of the fluid based on any variations from the predefined shape of the incident beam.

Abstract: A fluid level monitor for sensing the level of fluid in a reservoir such as for sensing an oil level in an internal combustion engine crankcase containing a quantity of oil, the monitor includes a light source for generating a light beam having a frequency which causes fluorescence in the fluid and a fiber optic cable for transmitting the light beam to the reservoir for exciting the fluid in the reservoir to generate fluorescent radiation and for receiving the fluorescent radiation emitted by the fluid as a result of the excitation. The monitor also includes a photodetector for receiving the fluorescent radiation and for generating a signal which is a function of the intensity of the received fluorescent radiation and a display for receiving the signal to indicate the level of fluid in the reservoir.