Optical fuel level sensor

An optical fluid level sensor for use with a fluid vessel, comprising;

• a waveguide capable of conducting light and having an outer periphery that includes a plurality of tiered facets, each of said tiered facets being capable of both reflecting light internally within said waveguide and refracting light out of said waveguide according to the absence or presence of fluid against said tiered facet, said waveguide also including a calibration feature located at a predetermined position,
• said calibration feature includes a tiered facet having a different size than other tiered facets,
• a photo source capable of emitting light into said waveguide, and
• a photo receiver capable of receiving light from said waveguide, wherein said sensor is capable of utilizing the light received by said photo receiver to provide an electronic fluid level signal representative of a fluid level within the vessel and wherein said sensor is further capable of providing calibration information in 4n electronic signal that identifies when the fluid level reaches said predetermined position.

An optical fluid level sensor for use with a fluid vessel, comprising:

• a waveguide capable of conducting light and having an outer periphery that includes a plurality of tiered facets, each of said tiered facets being capable of both reflecting light internally within said waveguide and refracting light out of said waveguide according to the absence or presence of fluid against said tiered facet,
• said tiered facets comprise first and second sets of opposing angled surfaces, with each of said first and second sets extending along an opposite side of said outer periphery,
• said waveguide also including a calibration feature located at a predetermined position,
• said calibration feature includes a first angled surface of said first set and a second angled surface of said second set, said first and second angled surfaces having a different size than other angled surfaces of said first and second sets,
• a photo source capable of emitting light into said waveguide, and
• a photo receiver capable of receiving light from said waveguide, wherein said sensor is capable of receiving the light received by said photo receiver to provide an electronic fluid level signal representative of a fluid level within the vessel and wherein said sensor is further capable of providing calibration information in an electronic signal that identifies when the fluid level reaches said predetermined position.

An optical fluid level sensor for use with a fluid vessel, comprising:

• a waveguide capable of conducting light and having an outer periphery that includes a plurality of tiered facets, each of said tiered facets being capable of both reflecting light internally within said waveguide and refracting light out of said waveguide according to the absence or presence of fluid against said tiered facet,
• said tiered facets comprise first and second sets of opposing angled surfaces, with each of said first and second sets extending along an opposite side of said outer periphery,
• said waveguide also including a calibration feature located at a predetermined position,
• said calibration feature includes a first longitudinal segment located between adjacent angled surfaces of said first set and a second longitudinal segment located between adjacent angled surfaces of said second set, said first and second longitudinal segments having a different length than other longitudinal segments of said first and second sets,
• a photo source capable of emitting light into said waveguide, and
• a photo receiver capable of receiving light from said waveguide, wherein said sensor is capable of utilizing the light received by said photo receiver to provide an electronic fluid level signal representative of a fluid level within the vessel and wherein said sensor is further capable of providing calibration information in an electronic signal that identifies when the fluid level reaches said predetermined position.

A fuel level sensing system for use with a fuel tank, comprising;

• a power source having an output for providing an electrical power signal,
• an optical fuel level sensor mounted within the fuel tan, said sensor comprising:
• a waveguide capable of conducting light and having an outer periphery that includes a plurality of tiered facets, each of said tiered facers being capable of both reflecting light internally within said waveguide and refracting light out of said waveguide according to the absence or presence of fluid against said tiered facet, said waveguide also including a calibration feature having at least one tiered facet located at a predetermined position and capable of both reflecting light internally within said waveguide and refracting light out of said waveguide according to the absence or presence of fluid against said tiered facet, said at least one tiered facet of the calibration feature having at least one of a different size and a longitudinal waveguide segment of a different length than the other tiered facets,
• a photo source capable of emitting light into said waveguide,
• a photo receiver capable of receiving light from said waveguide, and
• a signal output for providing an electronic fuel level signal, wherein said sensor is capable of utilizing the light received by said photo receiver to provide said fuel level signal which is representative of the fuel level within the fuel tank and wherein said sensor is further capable of utilizing light received from said tiered facet of the calibration feature to provide calibration information in an electronic signal, and
• an interface electronics unit having a first input coupled to said signal output of said sensor for receiving said fuel level signal and a second input coupled to said power source output for receiving said power signal, wherein said electronics unit is capable of utilizing said fuel level signal to determine the fuel level within the fuel tank and wherein said electronics unit is capable of receiving and utilizing said calibration information to calibrate said sensor with reference to said predetermined position.

A fuel level sensing system for use with a fuel tank, comprising:

• a power source having an output for providing an electrical power signal,
• an optical fuel level sensor mounted within the fuel tank, said sensor comprising:
• a waveguide capable of conducting light and having a tapered first axial end, a tapered second axial end, and an outer periphery that includes a plurality of tiered facets, each of said tiered facets being capable of both reflecting light internally within said waveguide and refracting light out of said waveguide according to the absence or presence of fuel against said tiered facet,
• a photo source located at a position approximately equidistant from said first and second axial ends and being capable of emitting light into said waveguide in a first direction generally towards said first axial end and in a second direction generally towards said second axial end,
• a photo receiver located at a position approximately equidistant from said first and second axial ends and being capable of receiving light from within said waveguide from said first and second directions,
• a signal output for providing an electronic fuel level signal, and
• an interface electronics unit having a first input coupled to said signal output of said sensor for receiving said fuel level signal, and a second input coupled to said power source output for receiving said power signal, wherein said sensor is capable of utilizing the light received by said photo receiver from said first and second directions to provide said fuel level signal which said electronics unit utilizes TO determine the fuel level within the fuel tank.

An optical fuel level sensor for use with a fuel tank, comprising:

• a waveguide capable of conducting light and having a tapered first axial end, a tapered second axial end, an outer periphery that includes a plurality of tiered facets, each of said tiered facets being capable of both reflecting light internally within said waveguide and refracting light out of said waveguide according to the absence or presence of fuel against said tiered facet, said waveguide also including a calibration feature located at a predetermined position,
• a photo source located at a position approximately equidistant from said first and second axial ends and being capable of emitting light into said waveguide in a first direction generally towards said first axial end and in a second direction generally towards said second axial end, and
• a photo receiver located at a position approximately equidistant from said first and second axial ends and being capable of receiving light from within said waveguide from said first an second directions, wherein said sensor is capable of utilizing the light received by said photo receiver from said first and second directions to provide an electronic fuel level signal representative of a fuel level within the fuel tank and wherein said sensor is further capable of providing calibration information in an electronic signal that identifies when he fuel level reaches said predetermined position.