Patent ID: 7652244

Claim:
A reflective optical sensor for sensing the presence of an object comprising: a reflective sensor package made of a resilient plastic material comprising: a first cavity including two opposing outwardly sloped sidewalls; and a second cavity including two opposing outwardly sloped sidewalls, the second cavity located next to the first cavity in the sensor package such that a physical barrier is disposed between the first and second cavities, wherein the physical barrier becomes gradually thinner between the openings of the first and second cavities toward the openings of the first and second cavities due to the outwardly sloped sidewalls of the first and second cavities, wherein the first and second cavities are only partially filled with an at least partially transparent resin; a VCSEL located within the first cavity for producing an optical emission; a shunt phototransistor including reverse bias protection located within the second cavity configured to receive at least a portion of the produced optical emission reflected off of the object, the shunt phototransistor including reverse bias protection comprising: an emitter; a collector; a base; a diode including an anode and a cathode, the anode being electrically coupled with the base, and the cathode being electrically coupled with the collector; a shunt internal resistor electrically coupled between the anode and the emitter creating a PN junction relationship, the PN junction relationship being disposed in parallel electrical relationship with the diode and the first resistor; and a reverse bias protection internal resistor coupled in electrical communication between the first resistor and the emitter.