JP2006084577A - Portable terminal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a portable terminal device realizing a simple image special effect (fade-in and fade-out) without performing image processing when changing images of a still picture and an animation. <P>SOLUTION: When changing images to be displayed on a translucent type LCD 31, display control of the LCD 31 and brightness control of a backlight 41 are synchronized so that brightness of the backlight 41 may change gradually from a turn-on state to a turn-off state before image changing timing and the brightness of the backlight 41 may change gradually from the turn-off state to the turn-on state after the image changing timing. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mobile terminal device, and more particularly to a mobile terminal device capable of displaying an image special effect.

  As a backlight control method of a conventional portable terminal device (hereinafter also simply referred to as “portable terminal”), for example, there is one described in Patent Document 1. This is a method of controlling the lighting brightness of the backlight and gradually darkening the backlight from the lighting state and turning it off. The backlight current flowing to the backlight is turned on and off based on a pulse train of a predetermined cycle. The backlight brightness is controlled by gradually reducing the pulse width of the pulse train according to a predetermined time characteristic so that the pulse width becomes zero.

FIG. 5 is a diagram illustrating an example of an image display operation in which backlight control and image special effect image processing are performed on a display screen that is recognized by the user. As shown in FIG. 5, in a conventional mobile terminal, for example, an image special effect by JAVA (registered trademark) is possible. Conventional backlight luminance control is controlled for the purpose of ON / OFF of the display screen. The backlight luminance control is turned on at the display image start timing t ₀ and is turned on until the display screen is turned off. In addition, in order to perform image special effect image processing, the image A ((), which has been subjected to image special effect image processing, is performed at timings t _1a and t _1b before and after the image display switching timing t ₁ between the images 1 and 2. By creating a fade-in) and drawing on the LCD illuminated by the backlight from the back, the user can see a display screen having image special effects. In order to create an image A (fade-in) having an image special effect, the control unit needs a processing load on the CPU and a work memory for image processing.
JP 2001-86232 A

  However, in the conventional portable terminal, the processing load of the CPU is heavy due to the high functionality of the application, and there are many applications that use a large amount of work memory. Therefore, when image processing is performed to realize the image special effect Furthermore, there is a problem that a processing load on the CPU and a work memory are required.

  The present invention has been made in view of the above points, and a simple image special effect (fade-in, fade-out) can be realized without performing image processing at the switching of images such as still images and moving images. It aims at providing a portable terminal device.

  The portable terminal device of the present invention includes a transmissive liquid crystal display, a backlight that illuminates light from the back surface of the liquid crystal display, display control means that controls image display on the liquid crystal display, and brightness of the backlight. Brightness control means that synchronizes the display control means and the brightness control means so that the brightness of the backlight changes before and after the image switching timing when switching the image displayed on the liquid crystal display. And a configuration having the following.

  According to the present invention, a simple image special effect (fade-in, fade-out) can be realized without performing image processing at the switching of images such as still images and moving images.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a mobile terminal device according to an embodiment of the present invention.

  A mobile terminal 1 shown in FIG. 1 stores a control unit 10 that controls the entire mobile terminal, an internal memory 20 that stores programs and operation modes for operating the control unit 10, and information on still images and moving images. An external storage unit 21, a transmissive LCD (Liquid Crystal Display) 31 that is a display screen for a user to view an image display, an LCD driver 30 that controls the LCD 31, and a rear surface of the transmissive LCD 31. It includes a backlight 41 that illuminates light, a backlight lighting circuit 40 that drives the backlight 41, and an operation unit 60 having keys that are man-machine interfaces for performing various settings of the mobile terminal 1.

  The control unit 10 includes a display control unit 11 that performs display control for drawing on the LCD 31 through the LCD driver 30, and a backlight luminance control unit 12 that performs ON / OFF of the backlight 41 and luminance control through the backlight lighting circuit 40. In order to realize the image special effect, the display control unit 11 and the backlight luminance control unit 12 are configured by a synchronization control unit 13 that synchronizes the two control units.

  The display screen 50 includes an LCD 31 and a backlight 41 that shines light from the back surface of the LCD 31. The user can visually recognize the display screen 50. Since the display screen 50 includes the LCD 31 and the backlight 41 as described above, the user can recognize the contents of the display screen.

  The display operation modes include a normal image display mode for performing normal image display without image special effects and a special effect image display mode for performing image display with image special effects. The user performs key input through the operation unit 60 to set the display operation mode from the normal image display mode to the special effect image display mode (and vice versa), or to set the backlight luminance change speed to an arbitrary speed. Can be performed.

  Next, an image display operation of the mobile terminal 1 having the above configuration will be described.

  First, the normal image display operation on the display screen 50 will be described with reference to FIG.

When drawing on the LCD 31, the display control unit 11 first draws the image 1 on the LCD 31. At this time, since the LCD 31 is a transmissive LCD, even if an image is drawn on the LCD 31, the user can hardly recognize the drawing state if there is no light from the back side. Therefore, because of display start of the display screen 50, backlight luminance controller 12 at the timing of t _0, the backlight 41 are lit. Thereby, light enters from the back of the LCD 31 and the user can recognize the image on the display screen 50.

In normal image display, the backlight luminance control unit 12 performs control for turning on / off without gradually changing the luminance of the backlight. For this reason, it seems to the user that the display screen 50 is displayed instantly. Once the backlight 41 is turned on at the timing t _0, the backlight luminance control unit 12 keeps the backlight 41 in a fixed luminance state until the display screen 50 is turned off. The image 1, image 2, image 3, and image 4 are drawn on the LCD 31 in order, so that the image is displayed on the display screen 50.

  Next, the special effect image display operation on the display screen 50 will be described with reference to FIGS.

  When the special effect image display is performed on the display screen 50, the LCD 31 draws the normal image display as usual, and the backlight luminance control unit 12 controls the luminance of the backlight 41 in synchronization with the image of the normal image display. By doing so, special image effects are realized.

  The normal image display and the operation of the backlight 41 at the time of switching between the image 1 and the image 2 in FIG. 3 will be described with reference to FIG.

Usually draw a display image on the LCD 31, and turns off gradually lowered the luminance of the backlight 41 at the timing of _{t 1} from t _1a, switches the normal image display from the image 1 to the image 2 at the timing _{t 1,} from _{t 1} At the timing of t _1b , the luminance of the backlight 41 is gradually increased to light up. Thus, the display screen 50 becomes an image A1 that looks like a fade-out image special effect from t _1a to t ₁ , and an image A2 that looks like a fade-in image special effect from t ₁ to t _1b . Therefore, a simple image special effect can be realized without the CPU processing load and the image processing work memory.

  As a method of gradually changing the luminance of the backlight 41, for example, the backlight luminance control unit 12 changes the set value of the current for periodically turning on the backlight 41 under the control of software, There is a method in which a hardware timer is provided in the light lighting circuit 40 to set a target value, and thereafter, the hardware periodically changes until the brightness of the current value that is the target set value is reached.

  As described above, according to the present embodiment, the means for controlling the luminance of the backlight 41 from the unlit state to the gradually lit state, or from the lit state to the gradually unlit state, and the image display on the transmissive LCD 31 are displayed. And a means for synchronously controlling them, and adjusting the timing of the luminance control of the backlight 41 and the display control of the transmissive LCD 31, that is, by synchronizing both controls, the image special effect ( (Fade-in, fade-out) is realized, so that simple image special effects can be realized even on portable terminals with low CPU processing performance without the processing load of the CPU and without the need for image processing work memory. Can do.

  The mobile terminal device according to the present invention has an effect that a simple image special effect (fade-in, fade-out) can be realized without performing image processing at the switching of images such as still images and moving images, It is useful as a portable terminal device with a simple image special effect equipped with a transmissive LCD as a display screen.

The block diagram which shows the structure of the portable terminal device which concerns on one embodiment of this invention The figure for demonstrating the operation | movement of the normal image display in the portable terminal device which concerns on this Embodiment The figure for demonstrating operation | movement of the special effect image display in the portable terminal device which concerns on this Embodiment The figure which shows the principal part of FIG. 3 in detail The figure which shows an example of the operation | movement of the image display which performed the image processing of the conventional backlight control and image special effect

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Portable terminal 10 Control part 11 Display control part 12 Backlight brightness | luminance control part 13 Synchronization control part 20 Internal memory 21 External storage part 30 LCD driver 31 LCD
40 Backlight Lighting Circuit 41 Backlight 50 Display Screen 60 Operation Unit

Claims (4)

A transmissive liquid crystal display;
A backlight that shines light from the back of the liquid crystal display;
Display control means for controlling image display on the liquid crystal display;
Brightness control means for controlling the brightness of the backlight;
A synchronization control unit that synchronizes the display control unit and the luminance control unit so that the luminance of the backlight changes before and after the timing of switching the image when switching the image displayed on the liquid crystal display;
A portable terminal device comprising: The synchronization control means includes
Before the timing for switching the image, the luminance of the backlight gradually changes from the lit state to the unlit state, and after the timing for switching the image, the luminance of the backlight gradually changes from the unlit state to the lit state. , Performing synchronous control for the display control means and the brightness control means,
The mobile terminal device according to claim 1.   The portable terminal device according to claim 1, wherein a backlight luminance change rate in backlight luminance control by the luminance control unit can be arbitrarily set by a user operation. A transmissive liquid crystal display;
A backlight that shines light from the back of the liquid crystal display;
Display control means for controlling image display on the liquid crystal display;
A brightness control means for controlling the brightness of the backlight, and a method for performing image special effect display in a portable terminal device comprising:
When switching an image to be displayed on the liquid crystal display, the luminance of the backlight gradually changes from a lighting state to a non-lighting state before the timing for switching the image, and after the timing for switching the image, the luminance of the backlight The display control by the display control means and the brightness control by the brightness control means are synchronized so that gradually changes from the unlit state to the lit state.
An image special effect display method in a portable terminal device.

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