Proximity sensor having an optical routing module for guiding emitted light and target-reflected light

Patent metadata

Field	Value
Publication number	US-9778076-B2
Application number	US-201514935810-A
Country	US
Kind code	B2
Filing date	Nov 9, 2015
Priority date	Nov 18, 2014
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A proximity sensor for an electronic device comprises a proximity module, a lens and an optical module secured in an air gap therebetween. The proximity module has an emitter and a detector and is configured to generate a signal that is a function of light emitted by the emitter, and light detected by the detector, some portion of the detected light having been reflected by a target external to the electronic device. A transmissive-reflective surface of the optical module is aligned with the emitter field of view (FOV) and the detector FOV. The optical module guides emitted light through a transmissive portion of the lens to the exterior of the electronic device, and guides target-reflected light collected by the transmissive portion to the detector. The emitter FOV and the detector FOV are substantially aligned with one another.

First claim

What is claimed is:

1. A proximity sensor for an electronic device, the proximity sensor comprising:
a proximity module having an emitter to emit light in an emitter field of view (FOV) and a detector to detect light in a detector FOV, the proximity module configured to generate a signal that is a function of the emitted light and of the light incident on the detector in the detector FOV, wherein the signal is indicative of the presence of a target external to the electronic device;
a lens separated from the proximity module by an air gap, the lens having (i) a transmissive portion in alignment with the emitter FOV and with the detector FOV, and (ii) a non-transmissive portion that extends over an area that is opposite the detector; and
an optical routing module secured within the air gap, the optical routing module comprising a transmissive-reflective surface in alignment with the emitter FOV, with the detector FOV, and with the transmissive portion of the lens, wherein the transmissive-reflective surface is oriented at an angle of approximately 45°±10° with respect to the emitter FOV, and wherein the optical routing module is configured:
to guide the emitted light transmitted by the transmissive-reflective surface through the transmissive portion of the lens to the exterior of the electronic device; and
to guide target-reflected light collected by the transmissive portion of the lens to the detector by reflecting the target-reflected light using the transmissive-reflective surface, wherein the target-reflected light has been reflected by the target external to the electronic device.

2. The proximity sensor as claimed in claim 1 , wherein the optical routing module further comprises a reflective surface that is substantially coplanar with the transmissive-reflective surface and that is in alignment with the detector FOV, wherein the reflective surface is oriented at an angle of approximately 45°±10° with respect to the detector FOV, and wherein the optical routing module is further configured:
to guide the target-reflected light, previously reflected by the transmissive-reflective surface, to the detector by subsequently reflecting the target-reflected light off of the reflective surface.

3. The proximity sensor as claimed in claim 2 , wherein the transmissive-reflective surface and the reflective surface correspond to opposing faces of a substantially parallelepiped shaped structure comprising one or more optical elements.

4. The proximity sensor as claimed in claim 2 , wherein the transmissive-reflective surface of the optical routing module corresponds to a face of a first wedge-shaped element, wherein the reflective surface of the optical routing module corresponds to a face of a second wedge-shaped element, and wherein the first wedge-shaped element and the second wedge-shaped element are separated by a distance.

5. The proximity sensor as claimed in claim 1 , wherein the emitter is a laser and the emitter FOV is between 2° and 25°.

6. The proximity sensor as claimed in claim 1 , wherein the transmissive portion comprises an aperture that is bounded by the non-transmissive portion, the aperture having a diameter of approximately 1.2 mm.

7. The proximity sensor as claimed in claim 1 , wherein both the transmissive portion of the lens and the non-transmissive portion of the lens are treated with an anti-smudge coating.

8. The proximity sensor as claimed in claim 1 , wherein the transmissive portion is defined by the portion of the lens to which a transmissive coating is applied, the transmissive coating comprising one or more layers or printings of IR-transmissible ink that preferentially transmit light in the IR spectrum over light in the visible spectrum.

9. The proximity sensor as claimed in claim 1 , wherein the non-transmissive portion is defined by the portion of the lens to which a non-transmissive coating is applied, the non-transmissive coating comprising one or more layers or printings of non-transmissible ink that limit or prevent the transmission of the emitted light.

10. The proximity sensor as claimed in claim 1 , wherein the optical routing module is fabricated from a polycarbonate or from poly(methyl methacrylate) (PMMA).

11. An electronic device comprising:
a housing;
a host processor enclosed within the housing; and
a proximity sensor coupled to the host processor, the proximity sensor comprising:
a proximity module having an emitter to emit light in an emitter field of view (FOV) and a detector to detect light in a detector FOV, the proximity module configured to generate a signal that is a function of the emitted light and of the light incident on the detector in the detector FOV, wherein the signal is indicative of the presence of a target external to the electronic device;
a lens separated from the proximity module by an air gap, the lens having (i) a transmissive portion in alignment with the emitter FOV and with the detector FOV, and (ii) a non-transmissive portion that extends over an area that is opposite the detector; and
an optical routing module secured within the air gap, the optical routing module comprising a transmissive-reflective surface in alignment with the emitter FOV, with the detector FOV, and with the transmissive portion of the lens, wherein the transmissive-reflective surface is oriented at an angle of approximately 45°±10° with respect to the emitter FOV, and wherein the optical routing module is configured:
to guide the emitted light transmitted by the transmissive-reflective surface through the transmissive portion of the lens to the exterior of the electronic device; and
to guide target-reflected light collected by the transmissive portion of the lens to the detector by reflecting the target-reflected light using the transmissive-reflective surface, wherein the target-reflected light has been reflected by the target external to the electronic device.

12. The electronic device as claimed in claim 11 , wherein the optical routing module further comprises a reflective surface that is substantially coplanar with the transmissive-reflective surface and that is in alignment with the detector FOV, wherein the reflective surface is oriented at an angle of approximately 45°±10° with respect to the detector FOV, and wherein the optical routing module is further configured:
to guide the target-reflected light, previously reflected by the transmissive-reflective surface, to the detector by subsequently reflecting the target-reflected light off of the reflective surface.

13. The electronic device as claimed in claim 12 , wherein the transmissive-reflective surface and the reflective surface correspond to opposing faces of a substantially parallelepiped shaped structure comprising one or more optical elements.

14. The electronic device as claimed in claim 12 , wherein the transmissive-reflective surface of the optical routing module corresponds to a face of a first wedge-shaped element, wherein the reflective surface of the optical routing module corresponds to a face of a second wedge-shaped element, and wherein the first wedge-shaped element and the second wedge-shaped element are separated by a distance.

15. The electronic device as claimed in claim 11 , wherein the emitter is a laser and the emitter FOV is between 2° and 25°.

16. The electronic device as claimed in claim 11 , wherein the transmissive portion comprises an aperture that is bounded by the non-transmissive portion, the aperture having a diameter of approximately 1.2 mm.

17. The electronic device as claimed in claim 11 , wherein both the transmissive portion of the le

Assignees

• Blackberry Ltd

Inventors

• Lee Hsin Chin
• Broga Antanas Matthew
• Gao Yu

Classifications

• G06F3/041

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title

• G01S17/04

  Systems determining the presence of a target · CPC title

• G01D5/34 Primary

  the beams of light being detected by photocells · CPC title

• G01S7/4811 Primary

  common to transmitter and receiver · CPC title

• G01S17/026

  Physics · mapped topic