JPH1152930A - Backlight control device and program recording medium therefor - Google Patents

Abstract

(57) [Summary] [Problem] In a state where the backlight is automatically turned on in a dark place, the backlight is automatically turned off when no operation is performed for a certain period of time to extend the life of the battery. The backlight is easily turned on in a dark place. SOLUTION: A CPU 1 executes an E function on the condition that an input operation has not been performed for a certain period of time while an EL backlight 7 is turned on according to the surrounding brightness by an ABC function.
Even if the ABO that turns off the L backlight 7 functions, the EL backlight 7 is turned on again by performing some input operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to lighting of a backlight used as a light source for a transmission type liquid crystal display panel or the like.
The present invention relates to a backlight control device for controlling turning off and a program recording medium therefor.

[0002]

2. Description of the Related Art Conventionally, two types of backlight control methods are known. One of them is to automatically turn off the backlight when no key operation is performed even after a certain time has elapsed. ABO (Auto B)
Acklight OFF) function. The other one detects the brightness of the surroundings with an optical sensor and automatically turns on the backlight if the surroundings are dark and less than a predetermined amount of light,
The backlight is automatically turned off when the surrounding area is bright and the light amount is equal to or more than a predetermined light amount.
This is referred to as a “Backlight Control” function.
Here, the ABO function is a function for suppressing wasteful consumption of the battery and saving it, and the ABC function automatically turns on / off the backlight without operating the backlight ON / OFF switch. This is a function for reducing the burden on the user. In general, an ABO function is incorporated in a device in which an ABC function is incorporated.

[0003]

However, in the prior art, the ABO function is not operated when the ABC function is in the ON state where it can be operated. This is because if no operation is performed for a certain period of time while the backlight is turned on in a dark place and the backlight is turned off by the ABO function, if the surroundings are dark, the ABC will be turned off again.
Because the function will turn on the backlight,
This is because the ABO substantially does not function. Suppose A
Assuming that the ABO is activated while the BC function is in the ON state, it is difficult to manually turn on the backlight by operating the backlight ON / OFF key after the backlight is turned off by the ABO function in a dark place. The user has to search for the key at the place, which makes it difficult to operate the keys, and has the disadvantage that the character keys and the function keys are operated by mistake. The object of the present invention is to
Even if the backlight is turned on automatically in a dark place and the backlight is turned off automatically for a certain period of time without any operation for longer battery life, That is, the backlight can be easily turned on.

[0004]

The means of the present invention are as follows. According to the first aspect of the present invention, even when the lighting function of lighting the backlight according to the amount of ambient light is in operation,
The backlight turns off when no operation has been performed for a certain period of time, enabling the backlight to be turned on when no operation is performed for a certain period of time even when the backlight is on in a dark place. The backlight control means for turning off the light, and whether or not the input operation is performed when the input operation is performed in a state where the backlight is turned off by the control of the backlight control means. Input control means for processing the input operation to turn on the backlight. According to the first aspect of the present invention, even if the backlight is turned on in a dark place, the backlight can be turned off if no operation is performed for a certain period of time. In this unlit state, when the input operation is performed, regardless of what kind of input operation is performed, the input operation for turning on the backlight is performed as if the input operation was performed. That is, for example, when an arbitrary key on the keyboard or an arbitrary key on the touch panel is operated, input of a normal key code assigned to the key is prohibited, and the input processing is performed as an input operation of turning on a backlight. Is done. Therefore, even if the backlight is automatically turned on in a dark place and the operation is not performed for a certain period of time to automatically turn off the backlight to extend the battery life, The backlight can be easily turned on at the place.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram showing an overall configuration of a portable terminal device using a battery as a power supply. C
PU1 is a central processing unit that controls the overall operation of the portable terminal device according to various programs loaded in the RAM2. The storage device 3 includes a storage medium 4 in which an operating system, various application programs, data files, character font data, and the like are stored in advance, and a drive system thereof. The storage medium 4 is fixedly provided or removably mountable, and is constituted by a magnetic / optical storage medium such as a floppy disk, hard disk, optical disk, RAM card, or the like, and a semiconductor memory. In addition, the storage medium 4
The programs and data in are loaded into the RAM 2 under the control of the CPU 1 as needed. Further, the CPU 1 receives programs and data transmitted from other devices via a communication line or the like and stores them in the storage medium 4 or stored in a storage medium provided in other devices. Existing programs and data can be used via a communication line or the like. A key input device 5, a touch screen 6, an EL backlight 7, and an illuminance sensor 8, which are input / output peripheral devices, are connected to the CPU 1 through a bus line. Control.

The key input device 5 includes various keys on a keyboard. The touch screen 6 includes a liquid crystal display panel 6-1 on which a transparent touch panel 6-2 is stacked. Various touch keys are assigned to 2. Character string data and various commands input from the key input device 5 and the touch screen 6 are taken into the CPU 1. Here, the CPU 1 causes the input character string to be displayed and output on a text screen of the liquid crystal display panel 6-1 or writes the character string to the RAM2. The EL backlight 7 is an EL (electroluminescence) element used as a light source (backlight) for the transmission type liquid crystal display panel 6-1. The CPU 1 controls turning on / off of the EL backlight 7. The illuminance sensor 8 is an optical sensor that detects the brightness of the surroundings. When the EL backlight 7 is turned on, the CPU 1 determines that the light amount detected by the illuminance sensor 8 is equal to or more than a predetermined value (more than a preset OFR light amount). Then, the EL backlight 7 is turned off. If the detected light amount of the illuminance sensor 8 is equal to or less than a predetermined value (equal to or less than a preset ON light amount) in a state where the EL backlight 7 is turned off, the EL backlight 7 is turned off. The backlight 7 is turned on.
In this manner, the ABC function for controlling the turning on / off of the EL backlight 7 according to the surrounding brightness can be operated (A
It is possible to arbitrarily set whether to be in the BC on state or inactive state (ABC off state) by an input operation. When the CPU 1 detects that a key on the key input device 5 or the touch screen 6 has not been operated for a certain period of time while the EL backlight 7 is on, the CPU 1 turns off the EL backlight 7. As described above, the ABO function for turning off the EL backlight 7 on condition that the input operation has not been performed for a certain period of time is based on the AB
Operation is possible even when the C function is in the ON state. That is, the EL backlight 7 is controlled by the ABC function.
When the input operation has not been performed for a certain period of time in a state where is turned on, the EL backlight 7 can be turned off by the ABO function. At this time, when any key on the key input device 5 or the touch screen 6 is operated, the first key input at that time is displayed by EL.
It is treated as a key for turning on the backlight 7 and is not treated as a normal input.

FIG. 2 is a diagram showing a main configuration of the RAM 2.
Various memory areas are allocated to the RAM 2.
The ABO timer 2-1 is a timer used in the ABO function, and measures the time during which no key operation is performed while the EL backlight 7 is turned on. Here, every time any key operation is performed, the CPU 1 clears the measurement time of the ABO timer 2-1 and starts the measurement operation. In the ABC flag register 2-2, an ABC flag indicating whether the ABC function can be operated is set to an ON state or an OFF state is set. Also, the status flag register 2-3 is set to EL
A status flag indicating whether the backlight 7 is on or off is set. The CPU 1 controls the on / off of the EL backlight 7 with reference to this status flag.

Next, a backlight control operation in the portable terminal device will be described. Here, FIG. 3 is a state transition diagram showing how the EL backlight 7 is turned on / off, focusing on the relationship between the ABC function and the ABO function. That is, states (1) and (2) are when the ABC function is off, and state (1) is the EL backlight 7
Is lit (EL ON, ABC
OFF) and state (2) is when the EL backlight 7 is on (EL OFF, ABC OFF)
Is shown. States (3) and (4) are when the ABC function is on, and state (3) is when the EL backlight 7 is on (EL ON, AB
(CON)), state (4) is when the EL backlight 7 is off (EL OFF, ABC ON)
Is shown. The state (5) indicates a state in which the EL backlight 7 is turned on when the ABC function is interrupted (EL ON, ABC interrupted). The state (6) is a state peculiar to this embodiment.
(Half Auto Backlight Contr
ol) When the EL backlight 7 is turned off during the function (EL OFF, during HABC). Here, the HABC function means that the EL backlight 7 is automatically turned on by the ABC function, and thereafter, even if the EL backlight 7 is turned off by the ABO function, it is possible to return to the original ABC state again by an input operation. Means a possible function.

FIG. 3 shows “ON operation”, “OFF operation”, “ABO timeout”, “O
It indicates what state the state transitions to when “N or less light quantity”, “ON or more light quantity”, and “touch or key input”. Here, “ON operation” and “OFF operation” indicate ON / OFF operation of the backlight ON / OFF key,
“ABO timeout” indicates a case where the ABO function detects that no input operation has been performed for a certain period of time. Furthermore, "less than ON light", "more than OFF light"
Is E based on the amount of light detected by the illuminance sensor 8.
It shows a threshold value when turning on / off the L backlight 7. “Touch or key input” indicates a case where any key on the key input device 5 or the touch screen 6 is operated.

Now, in the state (1), "OFF operation"
Is performed, the state shifts to the state (2), and the EL backlight 7 is turned off. In addition, when “ABO timeout” occurs in the state (1), the state also shifts to the state (2). On the other hand, if “OFF light quantity or more” is detected in state (3), the state shifts to state (4) and the EL backlight 7
Is turned off. Further, when “ON light quantity or less” is detected in the state (4), the state shifts to the state (3) and the EL backlight 7 is turned on. Further, when the “ON operation” is performed in the states (3) and (4), the state shifts to the state (5),
The EL backlight 7 is turned on. In such an ABC suspended state, “OFF operation” is performed or “AB operation” is performed.
When "C timeout" is detected, the state returns to the state during ABC and shifts to the state (4). The feature of this embodiment is that the ABC function is in operation and the EL backlight 7
In the state where (3) is lit, “ABO timeout” is detected. In this case, HABC
The state shifts to the state (6), and when a touch or key input is performed in this state, the state shifts to the state (3) or (4) according to the surrounding brightness at that time.

The operation in this case will be described below with reference to the flowcharts shown in FIGS. Here, programs for implementing the functions described in these flowcharts are stored in the storage medium 4 in the form of program codes readable by the CPU 1, and the contents thereof are loaded into the RAM 2. . FIG. 4 is a flowchart showing a backlight control operation when an ABO timeout is detected. First, the CPU 1 reads the contents of the status flag register 2-3 (step A1).
It is determined whether the state is L ON or ABC OFF (1) (step A2). Here, if the state is (1), EL O
The state shifts to the FF, ABC OFF state (2), and the EL backlight 7 is turned off (step A3). At present, E
If the state is L ON and ABC ON (3) (step A4), the state shifts to state (6) during ELOFF HABC, and the EL backlight 7 is turned off (step A5).
If the current state is EL ON and ABC interrupted (4) (step A6), the state shifts to EL OFF and ABC ON state (4) and the EL backlight 7 is turned off (step A7).

FIG. 5 is a flowchart showing a backlight control operation when a touch or key input is performed. First, the CPU 1 reads the contents of the status flag register 2-3 (step B1), determines whether the status is EL OFF HABC (6) (step B2), and if the status is any of the other statuses (1) to (5). Normal input processing is performed in response to a touch or key input (step B3). That is, an input process is executed in response to an operation of a character key or a function key. Also, in step B2, the EL OF
When it is determined that the state is the state during F HABC (6), the amount of light detected by the illuminance sensor 8 is acquired, and the surrounding brightness at that time is determined again (step B).
4) If the surrounding area is brighter than the OFF light amount, normal input processing according to touch or key input is performed (step B7), and the state shifts to the EL OFF ABC ON state (4) and the EL backlight 7 is turned off. (Step B8). On the other hand, if the surroundings are darker than the ON light amount,
Since the touch or key input at that time is not handled as a normal input operation but as an input operation for turning on the backlight, the normal input is ignored (step B5).
Then, the state shifts to the EL ON, ABC ON state (3), and the EL backlight 7 is turned on (step B).
6).

As described above, in this backlight control device, the ABO function can be operated even during the ABC in which the ABC function is ON. Therefore, the EL backlight 7 is automatically turned on by the ABC function, and even if the EL backlight 7 is left in that state, the EL backlight 7 is turned off for a certain period of time, so that unnecessary consumption of the battery can be prevented. The state at this time is just AB
Unlike the O state, it is possible to return to the original ABC state again by any key operation on the key input device 5 or the touch screen 6, so that the EL backlight 7 can be easily turned on even in a dark place. Becomes possible. in this case,
Any key operation is not treated as normal data entry.

In the above-described embodiment, the EL element is used as the backlight. However, a fluorescent tube having a longer life may be used. In this case, a fluorescent tube backlight may be arranged beside the liquid crystal display panel. Further, the present invention is not limited to the portable terminal device, and is applicable to a digital display type electronic wristwatch or the like.

[0015]

According to the present invention, in a state where the backlight is automatically turned on in a place where the surroundings are dark, the backlight is automatically turned off because no operation is performed for a certain period of time, and the length of the battery is reduced. Even if the life is extended, the input operation for turning on the backlight again is not specified, and the backlight can be turned on by the input operation regardless of what kind of input operation is performed. The backlight can be easily turned on even in a dark place.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of a portable terminal device that performs backlight control.

FIG. 2 is a diagram showing a main configuration of a RAM 2.

FIG. 3 is a state transition diagram for explaining a backlight control operation.

FIG. 4 is a flowchart showing a backlight control operation at the time of ABO timeout.

FIG. 5 is a flowchart showing a backlight control operation at the time of touch or key input.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CPU 2 RAM 2-1 ABD timer 2-2 ABC flag register 2-3 Status flag register 3 Storage device 4 Storage medium 5 Key input device 6 Touch screen 6-1 Liquid crystal display panel 6-2 Touch panel 7 EL backlight 8 Illuminance Sensor

Claims (2)

[Claims] 1. A lighting function for turning off a backlight when no operation is performed for a certain period of time even when a lighting function for lighting a backlight according to the amount of ambient light is in operation. Backlight control means for turning off the backlight when no operation is performed for a certain period of time even when the backlight is turned on in a dark place, and the backlight is turned off by the control of the backlight control means. Input control means for performing processing as if an input operation to turn on the backlight was performed, regardless of what input operation was performed when the input operation was performed in the state where the input operation was performed. A backlight control device, characterized in that: 2. The computer has a light-off function for turning off the backlight when no operation is performed for a certain period of time, even if a lighting function for turning on the backlight in accordance with the amount of ambient light is in operation. Means for turning off the backlight when no operation has been performed for a certain period of time while the backlight is lit in a dark place by enabling operation, and the backlight is turned on by the operation of the lighting function When the input operation is performed while the backlight is turned off during the operation of the light-off function, regardless of what input operation is performed, the input for turning on the backlight is performed. A recording medium that stores a program for realizing a unit that performs processing as if an operation has been performed.