GB2373914A - Portable terminal equipment and a method of controlling backlight display therein - Google Patents

Portable terminal equipment and a method of controlling backlight display therein Download PDF

Info

Publication number
GB2373914A
GB2373914A GB0214796A GB0214796A GB2373914A GB 2373914 A GB2373914 A GB 2373914A GB 0214796 A GB0214796 A GB 0214796A GB 0214796 A GB0214796 A GB 0214796A GB 2373914 A GB2373914 A GB 2373914A
Authority
GB
United Kingdom
Prior art keywords
light emitting
battery
amount
monitoring
terminal equipment
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB0214796A
Other versions
GB2373914B (en
GB0214796D0 (en
Inventor
Masaki Suzuki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP34883499A external-priority patent/JP3483026B2/en
Application filed by NEC Corp filed Critical NEC Corp
Publication of GB0214796D0 publication Critical patent/GB0214796D0/en
Publication of GB2373914A publication Critical patent/GB2373914A/en
Application granted granted Critical
Publication of GB2373914B publication Critical patent/GB2373914B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/02—Power saving arrangements
    • H04W52/0209—Power saving arrangements in terminal devices
    • H04W52/0261—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level
    • H04W52/0267—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level by controlling user interface components
    • H04W52/027—Power saving arrangements in terminal devices managing power supply demand, e.g. depending on battery level by controlling user interface components by controlling a display operation or backlight unit
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133603—Direct backlight with LEDs
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/3406—Control of illumination source
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133621—Illuminating devices providing coloured light
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133626—Illuminating devices providing two modes of illumination, e.g. day-night
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2330/00—Aspects of power supply; Aspects of display protection and defect management
    • G09G2330/02—Details of power systems and of start or stop of display operation
    • G09G2330/021—Power management, e.g. power saving
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H04M1/22—Illumination; Arrangements for improving the visibility of characters on dials
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Mathematical Physics (AREA)
  • Theoretical Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Computer Hardware Design (AREA)
  • Optics & Photonics (AREA)
  • Human Computer Interaction (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)
  • Telephone Function (AREA)

Abstract

When the amount of remaining battery power is limited, the battery life can be extended while established functions can be maintained sufficiently available. A battery remaining power amount monitoring portion 4 monitors the amount of battery power remaining. On lighting the backlight within a liquid crystal display 1, when a controlling portion 6 determines that the amount of remaining battery power is higher than a predetermined level, based on the result of monitoring in the battery remaining power amount monitoring portion 4, the controlling portion 6 causes a desired light emitting element to emit light. However, when the controlling portion 6 determines that the amount of remaining battery power is lower than the predetermined level, it causes a light emitting element operable with a lower power consumption to emit light, thereby saving power consumption. With multiple-color light emitting elements, when the battery is low light emitting elements of a selected color operable with lower power consumption are used.

Description

PORTABLE TERMINAL EQUIPMENT AND METHOD OF CONTROLLING BACKLIGHT DISPLAY THEREIN BACKGROUND OF THE INVENTION This invention relates to portable terminal equipment, such as cordless and portable telephones, and to a method of controlling backlight display therein, and, in particular, relates to portable terminal equipment and to a method of controlling backlight display therein which allows an extended operating life of a battery therein.
Conventionally, PHS (Personal Handyphone System, or cordless) and portable (or mobile) telephones are configured to operate using a battery as their electrical power source.
When the amount of battery power remaining is lowered to a predetermined level, alarms or displayed messages or the like notify the users that the amount of remaining battery power is limited.
When receiving the notification, the users turn the power off. depending on the situation.
When alarms or displayed messages or the like notify the users of the limited amount of remaining battery power in the known portable terminal equipment such as PHS and portable telephones described above, then the equipment has a little amount of available remaining battery time thereafter. So, it is preferable to turn the power off. Therefore, even if more conversation or a long-time standby state is necessary, the power may be sometimes set to OFF.
Japanese Patent Laid-Open No. 11-184576 discloses a technique in which, when the amount of remaining battery
power is reduced, all functions are stopped except for voice communication, thereby allowing longer continuation of the conversation or standby state.
However, according to the disclosure of the above specification, because other functions than voice communications are stopped when the amount of remaining battery power is reduced, information cannot be displayed on the display device. So, there is a problem that the functions established in the terminal equipment cannot be sufficiently used.
SUMMARY OF THE INVENTION The invention in its various aspects is defined in the independent claims below, to which reference may now be made. Advantageous features are set forth in the appendant claims.
Two embodiments of the invention are described in more detail below. The first embodiment, described in detail with reference to the drawings, takes the form of terminal equipment in which a light emitting element which is operable with lower power consumption is used when the battery power is low. In a second embodiment, a color light emitting element operable with a selected color is used when the battery power is low.
As a result, in either case when the amount of remaining power of the battery is reduced to lower than a predetermined level, the quantity of current flowing through the light emitting elements is reduced, and thus their power consumption can be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a portable terminal equipment embodying the invention; and FIGS. 2 to 4 relate to an embodiment in accordance with our UK Patent Application NO. 0030045.9, publication No. 2,360, 386, out of which this application is divided, and of which the present invention is a modification.
In FIGS. 2 to 4: FIG. 2 shows a pulse waveform outputted from the controlling portion shown in FIG. 1; FIG. 3 shows a relation between the luminance of the backlight and the widths of the pulses outputted from the controlling portion in the liquid crystal display shown in FIG. 1 ; and FIG. 4 shows a flowchart for illustrating a method of controlling backlight display in the liquid crystal display for the portable telephone shown in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates portable terminal equipment showing only the configurations relating to a power supply and backlight display within a portable telephone.
In the equipment shown in FIG. 1, a portable telephone 10 comprises displaying means, here a liquid display 1, provided with multiple-color light emitting elements which are used as a backlight, here LED's, and displaying information ; an electrical power source, her a battery 2; a charging circuit 3 for charging the battery 2 with a current
supplied from an external power source (not shown) when the charging circuit 2 is connected thereto ; monitoring means for monitoring the amount of remaining power of the battery 2, here a battery remaining-power-amount monitoring portion 4; driving means for driving the multiple-color LED's provided in the liquid display 1, here an LED-driving portion 5; and a controlling portion 6 which, based on the result of monitoring in the battery remaining-power-amount monitoring portion 4, generates and outputs a pulse for the LED's to be driven by the LED-driving portion 5.
First, a method of controlling backlight display will be described for the liquid crystal display 1 within the portable telephone 10 configured as described above. This method is the method of our above-mentioned parent application No. 0030045.9 and is described first by way of introduction to the embodiments of the present invention.
FIG. 2 illustrates a pulse waveform outputted from the controlling portion 6 shown in FIG. 1, and FIG. 3 illustrates relations between the luminance of the backlight in the liquid crystal display 1 and the width of a pulse outputted from the controlling portion 6.
A pulse waveform outputted from the controlling portion 6 consists of a sequence of time periods of ON and OFF. Duty ratio is given as a ratio (W/T) of a pulse width (W) to a period (T) from the rising edge of an ON time to the rising edge of the next ON time.
In the ON time, the LED-driving portion 5 drives the LED's within the liquid crystal display 1, and thereby the backlight is lit. Also, in the OFF time, the LED-driving portion 5 does not drive the LED's within the liquid crystal display 1, and thereby the backlight is shutoff.
As shown in FIG. 3, when a pulse waveform outputted from the controlling portion 6 has a duty ratio of 100% or 75%, the luminance of the backlight is 100%. Also, when a pulse waveform outputted from the controlling portion 6 has a duty ratio of 50%, the backlight luminance is 50%. Further, when a pulse waveform outputted from the controlling portion 6 has a duty ratio of 0%, the backlight luminance is 0%. Thus, the longer the duty cycle is, the longer the light emitting time of LED is, and so the higher the luminance of the backlight.
FIG. 4 shows a flowchart for illustrating a method of controlling backlight display for the liquid crystal display 1 within the portable telephone 10 shown in FIG. ~1. When lighting of the backlight within the liquid crystal display 1 is required (step Sil), first a PWM width for a color LED to be lit is determined (step S2). Herein, PWM (pulse width modulation) means a method for controlling the timings of ON and OFF for each of the LED's, and a PWM width for each of the LED's determines a displayed color by the backlight.
Next, the controlling portion 6 determines as to whether the amount of remaining power of the battery 2 is higher than or equal to a predetermined level, based on the result of the monitoring of the amount of remaining power of the battery
2 in a battery remaining-power-amount monitoring portion 4 (step 3).
When the amount of remaining power of the battery 2 is determined to be lower than a predetermined level in step S3, the controlling portion 6 corrects the PWM width (ON time) to a narrower width than the width determined in step S2 (step S4).
Next, when the amount of remaining power of the battery 2 is determined to be higher than or equal to a predetermined level in step S3, the controlling portion 6 controls the LED-driving portion 5 based on the PWM width determined in step S2. Further, when the amount of remaining power of the battery 2 is determined to be lower than a predetermined level in step S3, the controlling portion 6 controls the LEDdriving portion 5 based on the PWM width corrected in step S4 (step 5).
Thereafter, the LED's within the liquid crystal display 1 are driven under the control of the LED-driving portion 5, and thereby the backlight is lit with a luminance depending on the PWM width determined in step S2 or the PWM width corrected in step SA.
As described above, when the result of monitoring in the battery remaining power amount monitoring portion 4 indicates that the amount of remaining power of the battery 2 is higher than or equal to a predetermined level, the controlling portion 6 uses a nor-. al PWM width to provide a backlight display having the luminance of 100 ; also, when the result of monitoring in the bactery
remaining power amount monitoring portion 4 indicates that the amount of remaining power of the battery 2 is lower than a predetermined level, the controlling portion 6 uses a narrower PWM width than the normal PWM width to provide a backlight display having the luminance of 25% or 50%.
As a result of this, even when the amount of remaining power of the battery 2 is limited, the consumption power of the backlight can be reduced while maintaining the backlight in an available state, and so can extend the operating life of the battery therein.
By the way, when the amount of remaining power of the battery 2 is lower than a predetermined level, the luminance of the backlight is not limited to such as described above, but any backlight luminance is allowable as far as the operating life of the battery 2 can be extended.
As described above, according to the embodiment of the parent application, the amount of remaining battery power is monitored by monitoring means, and on lighting of the backlight, if controlling means determines the amount of remaining battery power to be higher than or equal to a predetermined level on the basis of the result of monitoring in the monitoring means, the controlling means uses a determined pulse width as the pulse width driving light emitting elements used as a backlight, and when the controlling means determines the amount of remaining battery power to be lower than the predetermined level, the controlling means makes said pulse width narrower than the determined pulse width. As a result, when the amount of remaining battery power is limited, the quantity of a current flowing through the light emitting elements is reduced depending on a generated pulse, and thereby the
consumption power of the backlight can be reduced while the backlight is maintained in an available state. Thus, the operating life of the battery can be extended.
EMBODIMENTS OF THE PRESENT INVENTION Thus, in the method described above, even when the amount of remaining battery power is limited, the controlling of the luminance of a backlight based on the amount of remaining power of the battery reduces the power consumption of the backlight while maintaining the backlight in an available state. Thus the operating life of the battery can be extended.
In a first embodiment of the present invention, when the amount of remaining battery power is reduced to lower than a predetermined level, selecting a lower power LED independently of the emission color specified by users also makes it possible to reduce the consumption power of the backlight while maintaining the backlight in an available state. Then, not only the operating life of the battery can be extended, but also it is possible to make the users know the reduction in the amount of remaining battery power.
In a second embodiment of the present invention, even when the amount of remaining battery power is limited, automatically selecting of the emission color of LED's based on the remaining amount of a battery may be used to reduce the power consumption of a backlight while maintaining the backlight in an available state. Similarly, the operating life of the battery can be extended.
In general, when the amount of remaining battery power is reduced to lower than a predetermined level, a color light emitting element operable with lower power consumption
of multiple-color light emitting elements can be driven. Thereby, when the amount of remaining battery power is limited, the power consumption of the backlight can be reduced while the backlight is maintained in an available state, and thus not only the operating life of the battery can be extended, but also it is possible to make the users know the reduction of the amount of remaining battery power.
The invention may be embodied in other specific forms without departing from the essential characteristic thereof.
The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (10)

  1. CLAIMS 1. Portable terminal equipment comprising at least: displaying means provided with light emitting elements used as a backlight for displaying information, a battery operating as an electrical power source, monitoring means for monitoring the amount of remaining power of the battery, driving means for driving the light emitting elements, controlling means for generating and outputting a pulse for the light emitting elements to be driven by the driving means, when the result of the monitoring indicates that the amount of remaining power of the battery is higher than a predetermined level, causes a desired one of the light emitting elements to emit light; and when the result of the monitoring indicates that the amount of remaining electric power of the battery is lower than a predetermined level, causes a light emitting element operable with lower power consumption of the light emitting elements to emit light.
  2. 2. Portable terminal equipment according to claim 1, wherein the light emitting elements are multiple-color light emitting elements.
  3. 3. Portable terminal equipment comprising at least: displaying means provided with multiple-color light emitting elements used as a backlight for displaying information,
    a battery operating as an electrical power source, monitoring means for monitoring the amount of remaining power of the battery, driving means for driving the light emitting elements, controlling means for generating and outputting a pulse for the light emitting elements to be driven by the driving means, wherein the controlling means, when the result of monitoring in the monitoring means indicates that the amount of remaining power of the battery is lower than a predetermined level, causes said driving means to drive a color light emitting element of a selected color operable with lower power consumption of said multiple-color light emitting elements.
  4. 4. Portable terminal equipment according to any of claims 1 to 3, including a charging circuit for charging said battery with an externally supplied current.
  5. 5. Portable terminal equipment according to any of claims 1 to 4, wherein said displaying means is a liquid crystal display.
  6. 6. A method of controlling backlight display in portable terminal equipment in which a backlight is lit in a desired color by causing a desired light emitting element of a plurality of light emitting elements to emit light in displaying means for displaying information, the method comprising the steps of: monitoring the amount of remaining power of a battery for the portable terminal equipment;
    when the result of the monitoring indicates that the amount of remaining power of the battery is higher than a predetermined level, causing the desired light emitting element to emit light; and when the result of the monitoring indicates that the amount of remaining electric power of the battery is lower than a predetermined level, causing a light emitting element operable with lower power consumption of the light emitting elements to emit light.
  7. 7. A method of controlling backlight display in portable terminal equipment in which a backlight is lit in a desired color by causing a desired light emitting element of a plurality of multiple-color light emitting elements to emit light in displaying means for displaying information, the method comprising the steps of: monitoring the amount of remaining power of a battery for the portable terminal equipment; when the result of the monitoring indicates that the amount of remaining power of the battery is higher than a predetermined level, causing the desired light emitting element to emit light; and when the result of monitoring in the monitoring means indicates that the amount of remaining power of the battery is lower than a predetermined level, causing said driving means to drive a color light emitting element of a selected color operable with lower power consumption of said multiple-color light emitting elements.
  8. 8. A method of controlling backlight display in portable terminal equipment, substantially as either of the embodiments herein described.
  9. 9. Portable terminal equipment substantially as either of the embodiments herein described.
  10. 10. Portable terminal equipment according to any of claims 1 to 5 and 9, wherein the portable terminal equipment is a telephone handset.
GB0214796A 1999-12-08 2000-12-08 Portable terminal equipment and method of controlling backlight display therein Expired - Fee Related GB2373914B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP34883499A JP3483026B2 (en) 1999-12-08 1999-12-08 Portable terminal and backlight display method in portable terminal
GB0030045A GB2360386B (en) 1999-12-08 2000-12-08 Portable terminal equipment and method of controlling backlight display therein

Publications (3)

Publication Number Publication Date
GB0214796D0 GB0214796D0 (en) 2002-08-07
GB2373914A true GB2373914A (en) 2002-10-02
GB2373914B GB2373914B (en) 2003-05-14

Family

ID=26245408

Family Applications (1)

Application Number Title Priority Date Filing Date
GB0214796A Expired - Fee Related GB2373914B (en) 1999-12-08 2000-12-08 Portable terminal equipment and method of controlling backlight display therein

Country Status (1)

Country Link
GB (1) GB2373914B (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2471175A (en) * 2009-06-16 2010-12-22 Intel Corp Power conservation for a mobile device display
US8254957B2 (en) 2009-06-16 2012-08-28 Intel Corporation Context-based limitation of mobile device operation
US8776177B2 (en) 2009-06-16 2014-07-08 Intel Corporation Dynamic content preference and behavior sharing between computing devices
US8904164B2 (en) 2009-06-16 2014-12-02 Intel Corporation Multi-mode handheld wireless device to provide data utilizing combined context awareness and situational awareness
US9092069B2 (en) 2009-06-16 2015-07-28 Intel Corporation Customizable and predictive dictionary

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11183901A (en) * 1997-12-18 1999-07-09 Casio Comput Co Ltd Display device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11183901A (en) * 1997-12-18 1999-07-09 Casio Comput Co Ltd Display device

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2471175A (en) * 2009-06-16 2010-12-22 Intel Corp Power conservation for a mobile device display
GB2471175B (en) * 2009-06-16 2012-06-13 Intel Corp Power conservation for mobile device displays
US8254957B2 (en) 2009-06-16 2012-08-28 Intel Corporation Context-based limitation of mobile device operation
US8446398B2 (en) 2009-06-16 2013-05-21 Intel Corporation Power conservation for mobile device displays
US8776177B2 (en) 2009-06-16 2014-07-08 Intel Corporation Dynamic content preference and behavior sharing between computing devices
US8803868B2 (en) 2009-06-16 2014-08-12 Intel Corporation Power conservation for mobile device displays
US8904164B2 (en) 2009-06-16 2014-12-02 Intel Corporation Multi-mode handheld wireless device to provide data utilizing combined context awareness and situational awareness
US8909915B2 (en) 2009-06-16 2014-12-09 Intel Corporation Multi-mode handheld wireless device with shared mode to support cross-mode communications
US9092069B2 (en) 2009-06-16 2015-07-28 Intel Corporation Customizable and predictive dictionary

Also Published As

Publication number Publication date
GB2373914B (en) 2003-05-14
GB0214796D0 (en) 2002-08-07

Similar Documents

Publication Publication Date Title
US6738649B2 (en) Portable terminal equipment and method of controlling backlight display therein
US8018409B2 (en) Maximizing efficiency of battery-powered LED drivers
US6119023A (en) Digital portable telephone set having backlighted display with reduced power consumption
KR100945205B1 (en) Light emitting element drive device and mobile device using the same
US7932879B2 (en) Controlling electroluminescent panels in response to cumulative utilization
FI106770B (en) Illuminating electronic device and illumination method
KR101153219B1 (en) PWM signal generating circuit and method for DC-DC converter using diming signal and LED driving circuit for back light having the same
KR100455991B1 (en) Apparatus for controlling lcd backlight in mobile station
TWI422274B (en) Method and apparatus for illuminating light sources within an electronic device
US20070139316A1 (en) Led module with integrated controller
US20090195182A1 (en) Light Emission Control Circuit for Turning on a Plurality of Light Emitting Elements, and Lighting Apparatus and Portable Information Terminal Having the Same
US20080001547A1 (en) Driving parallel strings of series connected LEDs
US20090309502A1 (en) CONTROL CIRCUIT AND METHOD FOR CONTROLLING LEDs
KR20020066216A (en) Led drive circuit
JP2003152224A (en) High-efficiency led driving system
US7332879B2 (en) Control method and device for a power-converting module that drives a light-emitting component
GB2373914A (en) Portable terminal equipment and a method of controlling backlight display therein
EP2093812A1 (en) Portable terminal, and light emitter drive control method and light emitter drive control program employed in the portable terminal
JP2008193807A (en) Portable electronic apparatus
KR100485351B1 (en) Apparatus for controlling brightness of backlight using switch and method thereof
KR20040037301A (en) Apparatus for driving backlight of liquid crystal display
KR20000019807U (en) Called message informing apparatus in wireless telephone set
JP2001285471A (en) Portable terminal device
JP2001077914A (en) Mobile communications equipment
JP2003100494A (en) Discharge lamp light control device

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 20091208