Patent ID: 8808230

Claim:
An occlusion sensor system for detecting an occlusion in a flow path from an insulin infusion pump system, the occlusion sensor system comprising: a fluid channel that at least partially defines an insulin flow path between an insulin reservoir and an output port; a flexible membrane in fluid communication with the fluid channel so that fluid pressure in the fluid channel acts upon the flexible membrane; an air cavity positioned adjacent to the flexible membrane and generally opposite the fluid channel; a light transmissive member adjacent to the air cavity, the light transmissive member being arranged opposite the flexible membrane such that fluid pressure in the fluid channel above a threshold value causes the flexible membrane to deform into the air cavity and toward the light transmissive member; a primary light emitter configured to align with the light transmissive member and emit light into the light transmissive member; a light sensor configured to align with the light transmissive member and receive light from the primary light emitter that passes through the light transmissive member; and a reference light emitter configured to emit light that is received by the light sensor, wherein the reference light emitter is spaced apart from the primary light emitter.