Proximity sensor and control method thereof

• US 9,703,368 B2
• Filed: 07/29/2015
• Issued: 07/11/2017
• Est. Priority Date: 08/28/2014
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Cho, Youngjun, Kim, Sunuk, Joung, Munchae
• Primary Examiner(s): NGUYEN, SANG H
• Application Number:
  US14/812,616
• Publication Number:
  US 20160061588A1
• Time in Patent Office: 713 Days
• Field of Search: 250221, 2504591, 2504581, 2502521, 2503418, 250214 AL, 250241 B, 345102, 345 98
• CPC Class Codes: G04G 21/00 Input or output devices integrated in time-pieces
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/1684 Constructional details or arrangements related to integrated I/O peripherals not covered by groups G06F1/1635 - G06F1/1675
• CPC Class Codes: G06F 3/00 Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
• CPC Class Codes: H03K 17/941 using an optical detector H03K17/968 takes precedence
• CPC Class Codes: H03K 2217/94104 using a light barrier
• CPC Class Codes: H03K 2217/94111 having more than one emitter
• CPC Class Codes: H03K 2217/94116 increasing reliability, fail-safe
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04M 2250/12 including a sensor for measuring a physical value, e.g. temperature or motion telephones including GPS signal receivers H04M2250/10

Abstract

The present disclosure provides a proximity sensor including a light-emitting part that is configured to emit first light of a specific wavelength band, a light-receiving part that is configured to receive the first light and second light, the second light belonging to a different wavelength band from the first light, and a controller that is configured to recognize a proximate object based on the first light reflected by the proximate object, wherein the controller changes a light-reception range of the light-receiving part based on the second light.

Claims

1. A proximity sensor comprising:

a light-emitting part that is configured to emit a first light of a first wavelength band;

a light-receiving part that is configured to receive the first light of the first wavelength band emitted by the light-emitting part and a second light of a second wavelength band different from the first wavelength band, the second light emitted by a light source other than the light-emitting part; and

a controller that is configured to recognize a proximate object based on at least a portion of the first light of the first wavelength band that is reflected by the proximate object and received by the light-receiving part,

wherein the controller is configured to change a light-reception range of the light-receiving part based on an amount of illumination received from the second light of the second wavelength band, and

wherein the controller is configured to change, based on an amount of illumination received from the second light of the second wavelength band, a quantity and a light-emitting duration of the first light of the first wavelength band emitted by the light-emitting part based on comparing a predetermined value with an integral of time variations of received illumination comprising at least a portion of the first light of the first wavelength band that has been reflected and received by the light-receiving part.

2. The proximity sensor of claim 1, wherein the light-receiving part comprises:

an ambient light receiving device that is configured to receive ambient light; and

a filter that is configured to filter the first light of the first wavelength band and the second light of the second wavelength band from the ambient light.

3. The proximity sensor of claim 1, wherein the light-receiving part comprises:

a first light-receiving device that is configured to receive the first light of the first wavelength band emitted from the light-emitting part; and

a second light-receiving device that is configured to receive the second light of the second wavelength band.

4. The proximity sensor of claim 1, wherein the first wavelength band is in an infrared light wavelength band, and the second wavelength band is in a visible light wavelength band.

5. The proximity sensor of claim 1, wherein the light-emitting part is configured to emit the first light of the first wavelength band in a periodic manner.

6. The proximity sensor of claim 1, further comprising:

an analog-to-digital converter that is configured to convert an analog optical signal of the first light of the first wavelength band that is received by the light-receiving part into a digital optical signal.

7. The proximity sensor of claim 6, wherein the controller is configured to change, based on an amount of illumination from the second light of the second wavelength band received by the light-receiving part, an illumination range of the first light of the first wavelength band that is received by the light-receiving part and converted by the analog-to-digital converter.

8. The proximity sensor of claim 7, wherein the controller is configured to:

increase the illumination range of the first light of the first wavelength band received by the light-receiving part and converted by the analog-to-digital converter as a result of a larger amount of illumination from the second light of the second wavelength band received by the light-receiving part, and

decrease the illumination range of the first light of the first wavelength band received by the light-receiving part and converted by the analog-to-digital converter as a result of a smaller amount of illumination from the second light of the second wavelength band received by the light-receiving part.

9. The proximity sensor of claim 1, wherein the controller is configured to:

obtain a value by integrating, over the light-emitting duration, the quantity of the first light of the first wavelength band that is emitted by the light-emitting part;

control the output of the light-emitting part such that the value increases as a result of a larger amount of illumination from the second light of the second wavelength band received by the light-receiving part, and

control the output of the light-emitting part such that the value decreases as a result of a smaller amount of illumination from the second light of the second wavelength band received by the light-receiving part.

10. A mobile terminal comprising:

the proximity sensor according to claim 1; and

a display unit that is configured to display information processed in the mobile terminal,

wherein the display unit is configured to vary a display illumination based on the amount of illumination received from the second light of the second wavelength band.

11. A vehicle control apparatus comprising:

the proximity sensor according to claim 1; and

a display unit that is configured to display information processed in the vehicle control apparatus,

wherein the display unit is configured to vary a display illumination based on the amount of illumination received from the second light of the second wavelength band.

12. A method of controlling a proximity sensor, the method comprising:

emitting, by a light-emitting part, a first light of a first wavelength band;

receiving the emitted first light of the first wavelength band and a second light of a second wavelength band different than the first wavelength band, the second light emitted by a light source other than the light-emitting part;

changing a light-reception range of the first light of the first wavelength band based on an amount of illumination received from the second light of the second wavelength band;

recognizing a proximate object based on at least a portion of the first light of the first wavelength band that is reflected by the proximate object and received; and

changing, based on the amount of received illumination from the second light of the second wavelength band, a quantity and a light-emitting duration of the emitted first light of the first wavelength band based on comparing a predetermined value with an integral of time variations of received illumination comprising at least a portion of the first light of the first wavelength band that has been reflected and received.

13. The method of claim 12, wherein receiving the first light of the first wavelength band and the second light of the second wavelength band comprises:

receiving the first light of the first wavelength band by a first light-receiving device, and receiving the second light of the second wavelength band by a second light-receiving device.

14. The method of claim 12, wherein receiving the first light of the first wavelength band and the second light of the second wavelength band comprises:

receiving ambient light including the first wavelength band and the second wavelength band; and

filtering the first light of the first wavelength band and the second light of the second wavelength band from the ambient light.

15. The method of claim 12, wherein changing the light-reception range comprises changing an illumination range of the first light of the first wavelength band based on a received illumination of the second light of the second wavelength band as a result of an analog signal of the received first light of the first wavelength band being converted into a digital signal.