JP2008072273A - Liquid crystal display device and liquid crystal television with built-in dvd - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device for achieving screen saver function and power saving by the control of backlight. <P>SOLUTION: The liquid crystal display device 10 comprises: a plurality of backlights 21 including a plurality of light sources; and a screen saver function in which, when a predetermined time passes while displaying a still image, a first predetermined number of light sources are turned off in a first predetermined order, while a second predetermined number of light sources are turned on in a second predetermined order. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device including a backlight having a plurality of light sources and a DVD-integrated liquid crystal television.

  Generally, a DVD device is provided with a screen saver function. This function is to display a pre-prepared video when a still image is displayed for a predetermined time, such as when stopped during playback. In addition, there are some which reduce the luminance of the video output instead of displaying the video.

  In addition, some liquid crystal display devices display the external input of a DVD device or the like and reduce the backlight brightness or turn off the backlight when there is no input for a predetermined time. is there.

  For example, in Patent Literature 1, in a television broadcast receiver including a DVD device, the television microcomputer stores the start time of the sleep timer mode in a memory, and minimizes the brightness and contrast values of the screen output to the display unit. A configuration for value is disclosed.

  Patent Document 2 discloses a backlight control method for measuring the time when the input operation is interrupted and reducing the luminance of the backlight of the liquid crystal display device when the elapsed time reaches the monitoring time. .

Further, in Patent Document 3, when the viewer selects the external input terminal side using a remote controller or the like and there is no video signal input from the external input terminal side for a certain period of time, the display is performed by the OSD processing unit. A configuration of a liquid crystal television is disclosed in which backlights other than the backlight arranged opposite to the characters or figures displayed are turned off.
JP 2006-54827 A JP 2002-99248 A JP 2006-13942 A

  As described above, in the liquid crystal display device, power consumption is reduced by reducing the luminance of the backlight or turning off part of the backlight. Although power saving has been realized in the conventionally proposed backlight control, there is room for further improvement in order to improve usability.

  An object of the present invention is to provide a liquid crystal display device that realizes a screen saver function and power saving by controlling a backlight.

To achieve the above object, the present invention provides a liquid crystal display device having a backlight having a plurality of light sources.
When a predetermined time elapses in a state in which a still image is displayed, the light source is turned off in a first predetermined order by the first predetermined number while the still image is displayed, while the light source is in a second predetermined number. A screen saver function for lighting in a second predetermined order is provided.

  In the liquid crystal display device, the first and second predetermined numbers may be one.

  In the liquid crystal display device, the first and second predetermined orders may be the order in which the light sources are arranged.

  In the above liquid crystal display device, it is preferable that the number of the light sources that are lit when the screen saver function operates is always one or more.

The liquid crystal display device further includes a playback unit for playing back an optical disk on which video is recorded,
The still image may be an image read from the optical disc.

When the present invention is embodied, a backlight having a light source composed of three fluorescent lamps arranged in an upper stage, a middle stage, and a lower stage, a DVD recording / reproducing unit for reproducing a DVD on which video is recorded and a video on a DVD, In a DVD-integrated liquid crystal television equipped with
When a predetermined time elapses with still images read from a DVD displayed, the light sources are turned off one by one from the top while the still images are displayed, while the light sources are turned on one by one from the top. , Equipped with a screen saver function in which one or more light sources are always on,
If any operation input is made during the operation of the screen saver function, the operation of the screen saver function is terminated.

  According to the present invention, the screen saver function is realized by repeatedly turning off / on the light source by controlling the backlight, and power saving is realized by turning off the light source. Further, since the video used for the screen saver is not held, the storage capacity is not compressed.

  Hereinafter, as an example of a liquid crystal display device, a DVD integrated liquid crystal television in which a DVD recording / reproducing device and a liquid crystal television are integrated will be described. FIG. 1 is a block diagram showing the configuration of a DVD-integrated liquid crystal television 10 and its peripheral devices. The DVD-integrated liquid crystal television 10 is connected to an external device 11 typified by a video / audio recording device such as a set top box or a video deck such as a cable television or a satellite broadcast. The DVD-integrated liquid crystal television 10 can be operated by a remote controller 12.

  The DVD-integrated liquid crystal television 10 includes a tuner 13 that demodulates and digitizes a television broadcast signal received by an antenna, and compresses and encodes video / audio data received from the tuner 13 or the external device 11 in accordance with MPEG2 or the like. An audio / video compression / decompression unit 15 that decompresses and decodes the compressed image data reproduced by the recording / reproduction unit 14, and a compressed video / audio data received from the audio / video compression / decompression unit 15 is recorded on the inserted DVD. Or a DVD recording / reproducing unit 14 for reproducing data recorded on a DVD, a liquid crystal display unit 16 for displaying images, and various setting values can be set while being displayed on a part of the liquid crystal display unit 16. An OSD (On Screen Display) unit 17, an image output unit 18 that converts an image signal from the OSD unit 17 into an analog signal and outputs it to the liquid crystal display unit 16, and a sound Is output to the speaker 19, and the backlight 21 is provided on the back surface of the liquid crystal display unit 16 and has a plurality of light sources. Are connected to the backlight drive circuit 22 for controlling the drive of the backlight 21 for each light source, the memory 23 formed of ROM or RAM, the remote control receiver 24 for receiving a signal from the remote controller 12, and the external device 11. An external I / F 25 and a control unit 26 that controls each unit of the DVD-integrated liquid crystal television 10 are provided.

  As the light source of the backlight 21, a U-shaped tube, a straight tube fluorescent lamp, an LED, or the like can be used, and the arrangement thereof is not particularly limited. Moreover, the backlight drive circuit 22 can control lighting / extinguishing of each light source by including an inverter circuit connected to each light source.

  The control unit 26 also controls the operation of a screen saver function that appropriately controls the turning on / off of the light source of the backlight 21 when a predetermined time has elapsed with the still image displayed. The screen saver function will be described below.

  FIG. 2 is a flowchart showing the operation of the DVD-integrated liquid crystal television 10 when the screen saver function is executed. First, when a still image is displayed in step S10, the process proceeds to step S11 to determine whether or not a predetermined time has passed in a state where the still image is displayed. The displayed still image may be an image that was displayed when playback of the DVD was stopped, an image that was stopped using a function that stops the received TV broadcast video, or an external device 11 or the image input from 11. Also, the predetermined time may be set in advance to a time that is estimated that the user will not currently view for some reason, and can be set to, for example, 5 minutes. The predetermined time may be set at the time of manufacture or may be arbitrarily set by the user.

  When the predetermined time has elapsed in step S11, the process proceeds to step S12, and the light source of the backlight 21 is turned off in the first predetermined order by the first predetermined number while the still image is displayed, while the light source is switched to the second predetermined time. A screen saver process is performed in which the lights are turned on in a second predetermined order. Details of this screen saver process will be described later.

  On the other hand, if the predetermined time has not elapsed in step S11, the process proceeds to step S13 to determine whether or not the display of the still image has ended. The display of the still image is terminated when an operation is input from the remote controller. For example, an instruction to start reproduction can be given. When the display of the still image is finished in step S13, the process of this flowchart is finished. On the other hand, if the still image display continues in step S13, that is, if no operation is performed, the process returns to step S11.

  From step S12, the process proceeds to step S14. In step S14, it is determined whether or not an operation is input from the remote controller. If there is any operation in step S14, the process proceeds to step S15 to end the screen saver. Terminating the screen saver means controlling all the light sources of the backlight 21 so as to light normally. On the other hand, if there is no operation in step S14, the screen saver is maintained until some operation is performed.

  Next, the screen saver process described above will be described. Here, a case where the light source of the backlight 21 includes three fluorescent lamps will be described as an example. FIG. 3A shows the arrangement of the light sources. Three light sources 21 a to 21 c are arranged on the back surface of the liquid crystal display unit 16. FIG. 3B is a diagram illustrating an example of a still image displayed when the light sources 21a to 21c are all turned on in FIG. The still image 30 that is the letter A is displayed on almost the entire screen of the liquid crystal display unit 16, and since all the light sources 21a to 21c are lit as usual, the entire still image 30 can be visually recognized.

  When the screen saver process is executed, the light sources 21a to 21c are turned off in the first predetermined order by the first predetermined number while the still image 30 is displayed, while the light sources are turned in the second predetermined order by the second predetermined number. The light source 21a to 21c can be turned on / off, and various patterns can be considered for the turn-off / light-on operation control.

  For example, the case where the first and second predetermined numbers are 1 and the first and second predetermined orders are the order in which the light sources 21a to 21c are arranged, that is, the order of the light sources 21a, 21b, and 21c will be described. .

  In this case, the light source 21a is first turned off while the still image 30 is displayed. If it does so, the upper stage of the liquid crystal display part 16 will become dark, and the still image 30 will be in the state which cannot visually recognize the upper stage part, as shown to Fig.4 (a). Next, the light source 21a is turned on and simultaneously the light source 21b is turned off. Then, the middle stage of the liquid crystal display unit 16 becomes dark, and the still image 30 is in a state where the middle part cannot be seen as shown in FIG. Next, the light source 21b is turned on and the light source 21c is turned off at the same time. Then, the lower part of the liquid crystal display unit 16 becomes dark, and the still image 30 is in a state where the lower part cannot be visually recognized as shown in FIG. Next, the light source 21c is turned on and the light source 21a is turned off at the same time. Then, the still image 30 returns to the state shown in FIG.

  It should be noted that the time interval for changing from FIG. 4 (a) to FIG. 4 (b), FIG. 4 (b) to FIG. 4 (c), and FIG. 4 (c) to FIG. This is because the still image 30 appears to move. In addition to simultaneously turning on the previous light source and turning off the next light source as described above, the next light source may be turned off after the previous light source is turned on. Alternatively, the previous light source may be turned on after the next light source is turned off.

  Since the displayed image changes by repeating the above-described turn-off / light-on operation, the above processing can be used as a screen saver.

  Further, for example, the first and second predetermined numbers are 2, and the first and second predetermined orders are opposite to the order in which the light sources 21a to 21c are arranged, that is, the order of the light sources 21c, 21b, and 21a. You can also. Further, the first and second predetermined numbers and the first and second predetermined orders may be randomly changed during the screen saver process.

  As described above, in the screen saver process, the light source is turned off / lighted so that a part of the still image disappears. At this time, it is desirable that one or more light sources are always turned on. This is because when all the light sources are turned off, nothing is displayed on the liquid crystal display unit 16, and the user may misunderstand that the power is off.

  As described above, according to the above-described DVD-integrated liquid crystal television 10, the backlight 21 is controlled to repeatedly turn off / on the light source to realize the screen saver function, and to turn off the light source to realize power saving. Yes. Note that since the video used for the screen saver is not held, the capacity of the memory 23 is not compressed.

  INDUSTRIAL APPLICABILITY The present invention can be used for a liquid crystal display device as a monitor of a television or a personal computer, and can be effectively used for a liquid crystal television that can reproduce a video on a recording medium such as a DVD integrated liquid crystal television or an HDD integrated liquid crystal television.

It is a block diagram which shows the structure of DVD integrated liquid crystal television of this invention, and its peripheral device. It is a flowchart which shows operation | movement of the DVD integrated liquid crystal television at the time of performing the screen saver function of this invention. (A) is a figure which shows arrangement | positioning of a light source, (b) is a figure which shows an example of the still image displayed when all the light sources are lighted. (A) is a diagram showing a still image visually recognized when the upper light source is turned off, (b) is a diagram showing a still image visually recognized when the middle light source is turned off, and (c) is a lower light source. It is a figure which shows the still image visually recognized when it turns off.

Explanation of symbols

10 Liquid Crystal Display Device 14 DVD Recording / Reproducing Unit 21 Backlight

Claims (6)

A DVD-integrated liquid crystal comprising a backlight having a light source composed of three fluorescent lamps arranged in the upper, middle and lower stages, and a DVD recording / reproducing unit for reproducing a video recorded DVD and recording a video on the DVD On TV
When a predetermined time elapses with still images read from a DVD displayed, the light sources are turned off one by one from the top while the still images are displayed, while the light sources are turned on one by one from the top. , Equipped with a screen saver function in which one or more light sources are always on,
A DVD-integrated liquid crystal television set that terminates the operation of the screen saver function when any operation is input during the operation of the screen saver function. In a liquid crystal display device including a backlight having a plurality of light sources,
When a predetermined time elapses in a state in which a still image is displayed, the light source is turned off in a first predetermined order by the first predetermined number while the still image is displayed, while the light source is in a second predetermined number. A liquid crystal display device comprising a screen saver function that lights in a second predetermined order.   The liquid crystal display device according to claim 2, wherein the first and second predetermined numbers are one.   4. The liquid crystal display device according to claim 2, wherein the first and second predetermined orders are orders in which the light sources are arranged.   5. The liquid crystal display device according to claim 2, wherein at least one of the light sources that is lit during operation of the screen saver function is always one or more. A playback unit for playing back an optical disc on which video is recorded;
4. The liquid crystal display device according to claim 2, wherein the still image is an image read from the optical disc.

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