Optical sensor

A method for optical sensing of a substance comprising the steps of:

• providing an element transparent to selected wavelengths that are interactive with the substance, said element having a planar light incident surface and a planar measuring surface;
• directing optical energy including said selected wavelengths through said element from said light incident surface toward said measuring surface using a first light conducting means that is optically coupled to said light incident surface;
• contacting the measuring surface with the substance;
• measuring an intensity of optical energy transmitted through the element away from the measuring surface using a second light conducting means that is optically coupled to said light incident surface;
• and
• determining from such intensity of optical energy a physical property of the substance.

An optical sensor comprising:

• an optical energy source for supplying optical energy;
• an element including a material transparent to at least a portion of such optical energy defining a planar light incident and a planar measuring surface;
• light conducting means connecting the light source and the element for transmitting such optical energy through the element obliquely toward the measuring surface, said light conducting means being optically coupled to said element;
• a photodetector communicating with the element in a line of reflection of such optical energy from the measuring surface, said photodetector being responsive to a plurality of changes in an intensity of optical energy transmitted through the element away from the measuring surface, and being operative to generate an intensity signal that is related to the intensity of said optical energy reflected from said measuring surface;
• a temperature compensator coupled to said element and operative to produce a temperature compensated intensity signal that is a function of a physical property of a substance in contact with said measuring surface.

An optical sensor comprising:

• an optical energy source for supplying optical energy;
• an element including a material transparent to at least a portion of such optical energy defining a planar light incident and a planar measuring surface, said surfaces being spaced apart;
• light conducting means connecting the light source and the element for transmitting such optical energy through the element obliquely toward the measuring surface, said light conducting means being in abutting contact with said element;
• a photodetector communicating with the element in a line of reflection of such optical energy from the measuring surface, said photodetector being responsive to changes in an intensity of optical energy transmitted through the element away from the measuring surface, and being operative to generate an intensity signal that is proportional to said intensity;
• a temperature sensor coupled to said element for generating a compensating signal that is coordinated with said intensity signal to produce a temperature compensated output signal that is a function of a physical property of a substance in contact with said measuring surface.

An optical sensor comprising:

• an optical energy source for supplying optical energy;
• an element including a material transparent to at least a portion of such optical energy defining a planar light incident and a planar measuring surface, said surfaces being spaced apart;
• light conducting means connecting the light source and the element for transmitting such optical energy through the element obliquely toward the measuring surface, said light conducting means being optically coupled to said element;
• and
• a photodetector communicating with the element in a line of reflection of such optical energy from the measuring surface, said photodetector being responsive to a plurality of changes in an intensity of optical energy transmitted through the element away from the measuring surface, and being operative to generate a signal that is proportional to said intensity.