초록 ▼

A generated signal is passed through an elongated signal conveying element positioned preferably perpendicular to the surface of a fluid the level of which is to be measured. The signal is directed from the signal conveying element to a detector element which senses the signal output from the signal

A generated signal is passed through an elongated signal conveying element positioned preferably perpendicular to the surface of a fluid the level of which is to be measured. The signal is directed from the signal conveying element to a detector element which senses the signal output from the signal conveying element. The signal output detected in an optical embodiment varies logarithmically with the depth of immersion of the signal conveying element into the fluid. A preferred embodiment employs an electromagnetic wave, e.g., light, signal which passes through a light pipe signal conveying element. By nearly matching the light pipe index of refraction with that of the fluid, a predetermined precentage of the wave is lost into the fluid each time the light is reflected further along the pipe. The portion of light sensed at the detector, which is located where the unrefracted light exits, is readily converted to an output which varies linearly with the depth the light pipe signal conveying element is immersed into the fluid length.

대표청구항 ▼

An apparatus for providing an instantaneous measurement of the vertical displacement of a first fluid with a first index of refraction in reference to a second fluid with a second index of refraction, comprising: a source of a coherent electromagnetic energy beam; a detector for detecting said coher

An apparatus for providing an instantaneous measurement of the vertical displacement of a first fluid with a first index of refraction in reference to a second fluid with a second index of refraction, comprising: a source of a coherent electromagnetic energy beam; a detector for detecting said coherent electromagnetic energy beam; an energy conveying means, with a first end in communication with said source and a second end in communication with said detector, with an index of refraction selected to be essentially similar to said first index of refraction, immersed partially in said first fluid and partially in said second fluid, for conveying said coherent electromagnetic energy beam from said first end to said second end; means for introducing said coherent electromagnetic energy beam into said energy conveying means at an angle which produces reflection in said energy conveying means partially immersed in said second fluid and produces reflection and refraction in said energy convey means partially immersed in said first fluid wherein said refractions cause said coherent electromagnetic energy beam to be logarithmically diminished in said energy conveying means immersed in said first fluid; and a logarithmic amplifier for converting an output of said detector into an output signal which varies linearly with said vertical displacement of said first fluid.