Electronic devices including keypads that illuminate in response to proximity of a user and methods of operating such electronic devices

• US 6,498,600 B1
• Filed: 08/18/1999
• Issued: 12/24/2002
• Est. Priority Date: 08/18/1999
• Status: Expired due to Term

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Rudisill, Charles, Vance, Scott L.
• Primary Examiner(s): Saras, Steven
• Assistant Examiner(s): AWAD, AMR A
• Application Number:
  US09/376,239
• Time in Patent Office: 1,224 Days
• Field of Search: 345/156-179, 341/20-22, 400/472, 200/5.A, 200/5.R, 200/314
• US Class Current: 345/168
• CPC Class Codes: G06F 3/0202 Constructional details or processes of manufacture of the input device
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/807 characterised by the spatial arrangement of the contact sites, e.g. superimposed sites
• CPC Class Codes: H01H 2003/0293 with an integrated touch switch
• CPC Class Codes: H01H 2009/187 having symbols engraved or printed by laser
• CPC Class Codes: H01H 2219/03 in transparent keyboard
• CPC Class Codes: H01H 2219/036 Light emitting elements
• CPC Class Codes: H01H 2225/03 Different type of switches
• CPC Class Codes: H01H 2229/047 Preformed layer in mould
• CPC Class Codes: H01H 2229/05 Forming; Half-punching
• CPC Class Codes: H01H 2239/006 Containing a capacitive switch or usable as such
• CPC Class Codes: H01H 2239/07 UV or IR detection, e.g. of human body
• CPC Class Codes: H01H 2239/074 Actuation by finger touch
• CPC Class Codes: H01H 2300/022 Application wake up; switches or contacts specially provided for the wake up or standby shift of a circuit
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials
• CPC Class Codes: H04M 1/724 User interfaces specially adapted for cordless or mobile telephones

Abstract

An electronic device includes a keypad and a sensor that indicates proximity of a user to the electronic device, whereupon the keys of the keypad are illuminated. In particular, when the distance between the user and the sensor is less than a predetermined threshold, the keypad is illuminated in anticipation of the user providing keypad input to the electronic device. The sensor can be an infrared, an ultrasonic or a capacitive sensor. Alternately, the sensor can indicate contact between the user and the sensor, wherein the contact does not provide keypad input to the electronic device, for example, when the user touches but does not push a key of the keypad.

Claims

1. An electronic device comprising:

a processor that controls operations of the electronic device;

a keypad, electrically connected to the processor, including a plurality of keys, wherein the keypad provides keypad input to the electronic device when at least one of the plurality of keys is pushed;

a sensor, electrically connected to the processor, that indicates the proximity of the user to the sensor to the processor, wherein the processor determines the proximity of the user to the sensor;

a light, electrically connected to the processor, wherein the processor is configured to activate the light to illuminate the plurality of keys when the processor determines that the user is in contact with at least one of the plurality of keys, wherein the contact between the user and the at least one of the plurality of keys does not provide keypad input to the electronic device;

wherein the sensor includes a plurality of first contacts on the plurality of keys; and

a plurality of second contacts on the plurality of keys, wherein at least one of the plurality of first contacts is electrically connected to at least one of the plurality of second contacts through the user in response to contact between the user and the at least one of the plurality of keys.

2. The electronic device of claim 1, wherein the light does not illuminate the plurality of keys when the processor determines that the proximity of the user to the sensor indicated by the sensor is more than the predetermined threshold.

3. The electronic device of claim 1, wherein the light illuminates the plurality of keys when the processor determines that the user is in contact with at least two of the plurality of keys, wherein the contact between the user and the at least two of the plurality of keys does not provide keypad input to the electronic device.

4. The electronic device of claim 1, wherein the light does not illuminate the plurality of keys when the processor determines that the user is not in contact with at least one of the plurality of keys.

5. The electronic device of claim 1, wherein the sensor comprises one of a capacitive sensor, an ultrasonic sensor and an infrared sensor.

6. The electronic device of claim 1, wherein the sensor comprises:

a plurality of contacts on the plurality of keys; and

a comparator, electrically connected to the plurality of contacts, wherein the comparator provides a voltage level in response to proximity of the user.

7. The electronic device of claim 1, wherein the sensor comprises:

a plurality of first contacts on a plurality of first keys of the keypad; and

a plurality of second contacts on a plurality of second keys of the keypad, wherein the plurality of first contacts are electrically connected to the plurality of second contacts in response to contact between the user and at least one of the plurality of first keys and at least one of the plurality of second keys.

8. The electronic device of claim 1, wherein the contacts comprise a conductive material on the plurality of keys.

9. The electronic device of claim 8, wherein the conductive material is selected from a group consisting of gold, silver, copper, chrome, carbon and conductive silicon.

10. The electronic device of claim 1, wherein the keys comprise silicone rubber, injection molded plastic, or a flexible film having conductive ink thereon.

11. A keypad comprising:

a plurality of keys configured to provide keypad input to an electronic device when at least one of the plurality of keys of the keypad is pushed;

a sensor, on the plurality of keys, that indicates contact between a user and at least one of the plurality of keys, wherein the contact between the user and the at least one of the plurality of keys does not provide keypad input to the electronic device;

a light, responsive to the sensor, wherein the light illuminates the keys of the keypad in response to the indication of contact between the at least one of the plurality of keys and the user;

wherein the sensor includes a plurality of first contacts on the plurality of keys; and

a plurality of second contacts on the plurality of keys, wherein at least one of the plurality of first contacts is electrically connected to at least one of the plurality of second contacts through the user in response to contact between the user and at least one of the plurality of keys.

12. The keypad of claim 11, wherein the sensor indicates contact between the user and at least two of the plurality of keys.

13. The keypad of claim 12, wherein the sensor comprises:

a plurality of first contacts on a plurality of first keys of the keypad; and

a plurality of second contacts on a plurality of second keys of the keypad, wherein the plurality of first contacts are electrically connected to the plurality of second contacts in response to contact between the user and at least one of the plurality of first keys and at least one of the plurality of second keys.

14. The keypad of claim 12, wherein the contacts comprise a conductive material on the plurality of keys.

15. The keypad of claim 14, wherein the conductive material is selected from a group consisting of gold, silver, copper, chrome, carbon and conductive silicon.

16. The keypad of claim 11, wherein the keys comprise silicone rubber, injection molded plastic, or a flexible film having conductive ink thereon.

17. The keypad of claim 11 further comprising:

a detector, electrically connected to the sensor, that detects the contact between the user and the at least one of the plurality of keys based on the indication of contact from the sensor.

18. A keypad comprising:

means for providing keypad input to an electronic device when at least one of a plurality of keys of the keypad are pushed;

means for sensing contact between a user and at least one of the plurality of keys, wherein the contact between the user and the at least one of the plurality of keys does not provide keypad input to the electronic device;

means for illuminating the plurality of keys in response to the indication of contact between the at least one key and the user;

wherein the means for sensing includes a plurality of first contacts on the plurality of keys; and

a plurality of second contacts on the plurality of keys, wherein one of the plurality of first contacts is electrically connected to one of the plurality of second contacts through the user in response to contact between the user and at least one of the plurality of keys.

19. The keypad of claim 18, wherein the means for sensing indicates contact between the user and at least two of the plurality of keys.

20. The keypad of claim 19, wherein the means for sensing comprises:

a plurality of first contacts on a plurality of first keys of the keypad; and

a plurality of second contacts on a plurality of second keys of the keypad, wherein the plurality of first contacts are electrically connected to the plurality of second contacts in response to contact between the user and at least one of the plurality of first keys and at least one of the plurality of second keys.

21. The keypad of claim 19, wherein the contacts comprise a conductive material on the plurality of keys.

22. The keypad of claim 21, wherein the conductive material is selected from a group consisting of gold, silver, copper, chrome, carbon and conductive silicon.

23. The keypad of claim 18, wherein the keys comprise silicone rubber, injection molded plastic, or a flexible film having conductive ink thereon.

24. The keypad of claim 19 further comprising:

detector means for detecting the contact between the user and the at least one of the plurality of keys based on the indication of contact from the sensor.

25. A radiotelephone comprising:

a processor that controls operations of the radiotelephone;

a keypad, electrically connected to the processor, including a plurality of keys each having a key face, wherein the keypad provides keypad input to the radiotelephone when at least one of the plurality of keys is pushed;

first and second spaced-apart contacts on at least one of the key faces and an insulating material on the at least one key face between the first and second spaced-apart contacts, wherein the first and second spaced-apart contacts are configured to be electrically connected to one another when the at least one key face is contacted by a user and configured to be electrically insulated from one another in the absence of contact by a user; and

a light, electrically connected to the processor, wherein the processor is Configured to activate the light to illuminate the plurality of keys when the processor detects that the first and second spaced-apart contacts are electrically connected, wherein the contact between the user and the at least one key face does not provide keypad input to the radiotelephone.

26. The radiotelephone according to claim 25 wherein the first and second spaced-apart contacts are on respective spaced-apart first and second portions of the at least one key face.

27. The radiotelephone according to claim 26 wherein the first and second spaced-apart contacts comprise conductive ink.

28. The radiotelephone according to claim 25 wherein the at least one key is configured to provide no keypad input to the radiotelephone when in a non-depressed state and configured to provide keypad input to the radiotelephone when in a depressed state.