Optical proximity sensors
A proximity sensor, including a housing, an array of lenses mounted in the housing, an array of alternating light emitters and light detectors mounted in the housing, each detector being positioned along the image plane of a respective one of the lenses so as to receive maximum light intensity when light enters the lens at a particular angle, an activating unit mounted in the housing and connected to the emitters and detectors, synchronously co-activating each emitter with at least one of the detectors, each activated emitter projecting light out of the housing along a detection plane, and a processor receiving outputs from the detectors corresponding to amounts of projected light reflected by an object in the detection plane to the detectors, and calculating a two-dimensional location of the object in the detection plane based on the detector outputs and the particular angle.
1. A proximity sensor, comprising:
a housing;
an array of lenses mounted in said housing;
an array of alternating light emitters and light detectors mounted in said housing, each detector being positioned along the image plane of a respective one of said lenses so as to receive maximum light intensity when light enters the lens at a particular angle;
an activating unit mounted in said housing and connected to said emitters and detectors, synchronously co-activating each emitter with at least one of said detectors, each activated emitter projecting light out of said housing along a detection plane; and
a processor receiving outputs from said detectors corresponding to amounts of projected light reflected by an object in the detection plane to said detectors, and calculating a two-dimensional location of the object in the detection plane based on the detector outputs and the particular angle.
2. The proximity sensor of claim 1 , wherein each detector is positioned along the image plane of a respective second one of said lenses to receive maximum light intensity when light enters the second lens at a second particular angle, enabling said processor to calculate the two-dimensional location of the object in the detection plane based on the detector outputs and the second particular angle.
3. The proximity sensor of claim 2 , wherein the particular angle and the second particular angle for each lens are on separate sides of the lens's optical axis.
4. The proximity sensor of claim 1 , wherein each of said emitters is positioned such that the light it projects out of said housing passes through a respective one of said lenses.
5. The proximity sensor of claim 1 , wherein said array of alternating light emitters and light detectors comprises an array of diodes mounted on a single PCB, and wherein no light transmissive material separates the diodes from said lenses.
6. A car, comprising the proximity sensor of claim 1 mounted in the car body detecting objects on the car window.
7. The car of claim 6 , wherein an electronic system in the car responds to taps on the car window detected by the proximity sensor.
8. The car of claim 6 , wherein an electronic system in the car responds to gestures on the car window detected by the proximity sensor.
9. A building, comprising the proximity sensor of claim 1 mounted in a wall in the building, detecting objects on the wall.
10. The building of claim 9 , wherein an electronic system in the building responds to taps on the wall detected by the proximity sensor.
11. The building of claim 10 , further comprising a panel on the wall, the panel featuring digits or icons on which the taps are performed.
12. The building of claim 9 , wherein an electronic system in the building responds to gestures on the wall detected by the proximity sensor.