Self illumination circuit of a hand-held remote control device and self illumination method thereof

• US 5,705,997 A
• Filed: 05/30/1995
• Issued: 01/06/1998
• Est. Priority Date: 05/30/1994
• Status: Expired due to Fees

• Current Assignee: Daewoo Electronics (Government of South Korea)
• Original Assignee: Daewoo Electronics (Government of South Korea)
• Inventors: Park, Chan Soo
• Primary Examiner(s): Holloway, III, Edwin C.
• Application Number:
  US08/453,121
• Time in Patent Office: 952 Days
• Field of Search: 340/825.49, 340/825.55, 340/825.69, 340/825.72, 340/568, 340/571, 340/600, 341/176, 341/22, 345/169, 345/170, 359/142, 359/146, 359/48, 362/109, 200/310, 200/314, 200/315, 200/317, 455/352, 455/151.2, 348/734, 358/335, 315/159, 250/214 AL
• US Class Current: 340/8.1
• CPC Class Codes: F21V 33/0052 Audio or video equipment, e.g. televisions, telephones, cameras or computers; Remote control devices therefor

Abstract

A self illumination circuit of a hand-held remote control device and self illumination method make it easy to find and operate the remote control device when the remote control device is located in a dark environment. The circuit includes an illuminance sensing section, a contact sensing section, a key sensing section, a control section, a position indicating section, a key illuminating section, and a counter. If the illuminance sensing section senses illuminance of environment and transfers an illuminance sensing signal to the control section, the position indicating section indicates position of the remote control device according a position indicating signal from the control section. Upon receiving signals from the contact sensing section, the key sensing section, and the counter, the control section lights up, twinkles and puts out the key illuminating section.

Claims

1. A self illumination circuit of a hand-held remote control device, comprising:

an illuminance sensing section for sensing illuminance of environment to generate an illuminance sensing signal;

a contact sensing section for sensing contact of said remote control device to generate a contact sensing signal;

a key sensing section having a plurality of function keys, and for generating a key sensing signal;

a control section for receiving said illuminance sensing signal from said illuminance sensing section to generate a position indicating signal, receiving said contact sensing signal from said contact sensing section to generate a key illuminating signal and a time counting signal simultaneously while stopping the generation of said position indicating signal, and for receiving said key sensing signal from said key sensing section to generate a time counting stop signal;

a position indicating section having a plurality of position indicating lamps for receiving said position indicating signal from said control section to turning on said plurality of position indicating lamps;

a key illuminating section for receiving said key illuminating signal from said control section to illuminate said plurality of function keys; and

a counter for receiving said time counting signal to count time, for receiving said time counting stop signal to stop said time counting and then to reset said counted time to an initial value, wherein said control section resets said counted time to said initial value when receiving said key sensing signal, determines whether any of said plurality of function keys is touched when said counted time is less than a first preset value, twinkles said plurality of function keys when said counted time is equal to or greater than a first preset value and stops said twinkling when any of said plurality of function keys is touched, stops said illuminating of said plurality of function keys when said counted time is equal to or greater than a second preset value, and after stopping said illuminating, said control section determines whether said contact sensing signal is received and then determines whether any of said plurality of function keys is touched when said contact sensing signal is received, illuminates said key illuminating section when any of said plurality of function keys is touched and then resets said counted time to determine whether any of said plurality of function keys is touched again.

2. A self illumination circuit of a hand-held remote control device as recited in claim 1, wherein said illuminance sensing section includes an illuminance sensing member, a first resistor, a second resistor, a third resistor, and a transistor, said illuminance sensing member being connected to an operating power source through said first resistor, a base of said transistor being connected between said first resistor and said illuminance sensing member, a collector of said transistor being connected to said operating power source through said second resistor, and an emitter of said transistor being grounded.

3. A self illumination circuit of a hand-held remote control device as recited in claim 2, wherein said illuminance sensing member is comprised of a cadmium sulfide (CdS) having a resistance which varies with an illuminance around said remote control device so as to turn on and off said transistor, so that said illuminance sensing signal is transferred to said control section.

4. A self illumination circuit of a hand-held remote control device as recited in claim 1, wherein said plurality of position indicating lamps are light-emitting diodes.

5. A self illumination circuit of a hand-held remote control device as recited in claim 1, wherein said plurality of function keys are made of a transparent material.

6. A remote control device as recited in claim 5, wherein said key illumination section includes small lamps installed under said plurality of function keys.

7. A self illumination circuit of a hand-held remote control device as recited in claim 5, wherein said contact sensing section includes contact switches.

8. A self illumination circuit of a hand-held remote control device as recited in claim 7, wherein said contact switches are current sensing switches.

9. A self illumination circuit of a hand-held remote control device, comprising:

an illuminance sensing section for sensing illuminance of environment to generate an illuminance sensing signal, said illuminance sensing section having an illuminance sensing member, a first resistor, a second resistor, a third resistor, and a transistor, wherein said illuminance sensing member is in series connected to operating power through said first resistor, a base of said transistor is connected between said first resistor and said illuminance sensing member, a collector of said transistor is in series connected to said operating power through said second resistor, an emitter of said transistor is grounded, said illuminance sensing member is comprised of a cadmium sulfide having a resistance which varies with illuminance around said remote control device so as to turn on and off said transistor, so that said illuminance sensing signal is transferred to said control section;

a contact sensing section for sensing contact of said remote control device to generate a contact sensing signal, said contact sensing section including contact switches;

a key sensing section having a plurality of function keys, and for sensing whether any of said plurality of function keys is operated or not to generate a key sensing signal;

a control section for receiving said illuminance sensing signal from said illuminance sensing section to generate a position indicating signal, receiving said contact sensing signal from said contact sensing section to generate a key illuminating signal and a time counting signal simultaneously while stopping the generation of said position indicating signal, and receiving said key sensing signal from said key sensing section to generate a time counting stop signal;

a position indicating section having a plurality of position indicating lamps for receiving said position indicating signal from said control section to turn on said plurality of position indicating lamps, said plurality of position indicating lamps being light-emitting diodes for lighting up said position indicating section according to said position indicating signal from said control section;

a key illuminating section for receiving said key illuminating signal from said control section to illuminate said plurality of function keys, said plurality of function keys being made of a transparent material; and

a counter for receiving said time counting signal to count time, and for receiving said time counting stop signal to stop said time counting and then to reset a counted time into an initial value, wherein said control section resets the time to said initial value when receiving said key sensing signal, determines whether any of said function keys is touched when said counted time is less than a first preset value, twinkles said plurality of function keys when said counted time is equal to or greater than a first preset value and stops said twinkling when any of said plurality of function keys is touched, stops said illuminating of said plurality of function keys when said counted time is equal to or greater than a second preset value, and after stopping said illuminating, said control section determines whether said contact sensing signal is received and then determines whether any of said plurality of function keys is touched when said contact sensing signal is received, illuminates said key illuminating section when any of said plurality of function keys is touched and then resets the counted time to determine whether any of said plurality of function keys is touched again.

10. A self illumination method of a hand-held remote control device, said method comprising the steps of:

a) sensing an illuminance of environment;

b) determining whether the environment is dark or light, executing again said step a) in the light environment and turning on a plurality of position indicating lamps of said remote control device in the dark environment;

c) sensing whether said remote control device is touched or not, returning to said step a) if said remote control device is not touched, and turning off said plurality of position indicating lamps while lighting up a plurality of function keys if said remote control device is touched;

d) resetting a counted time to an initial value;

e) sensing whether any of said plurality of function keys is touched or not, repeating said step d) after stopping twinkling said plurality of function keys when any of said plurality of function keys is touched, and counting time by adding a predetermined value to said initial value when any of said plurality of function keys is not touched, wherein said step e) is executed if said counted time is less than a first preset value, said step e) is executed again after twinkling said plurality of function keys when said counted time is equal to or greater than said first preset value and less than a second preset value, and turning off said plurality of function keys when said counted time is equal to or greater than said second preset value;

f) sensing whether said remote control device is continuing in contact or not continuing in contact again, executing said step a) when said remote control device is not continuing in contact; and

g) sensing again whether any of said plurality of function keys is touched or not when said remote control device is continuing in contact in said step f), wherein said step f) is executed when any of said plurality of function keys is not touched and said step d) is executed after illuminating said plurality of function keys when any of said plurality of function keys is touched.