JP4488914B2 - Television receiver and video display method - Google Patents

Description

  The present invention relates to a television receiver and a video display method capable of receiving a plurality of different types of broadcasts and displaying program videos related to the received broadcasts.

  Due to recent technological advances, the transition from analog broadcasting to digital broadcasting has been progressing. In Japan, broadcasting from CS broadcasting using a communication satellite in 1996 was started, and BS broadcasting in 2000 was digitized. The digitization of terrestrial broadcasting in 2004 and the digitization of broadcasting are progressing one after another. In addition to television broadcasting, the digital broadcasting includes a plurality of different broadcasting types such as radio broadcasting and data broadcasting, and the user presses a broadcasting type switching key provided on, for example, a remote control device (hereinafter referred to as a remote controller). By operating, it is possible to select a desired broadcast type and view broadcast program content.

  For example, radio broadcasts include radio broadcasts that allow viewing of images and linked data, and audio-only radio broadcasts. Some programs can be played with high sound quality equivalent to a CD (compact disc). It is. Data broadcasting includes independent data broadcasting that specializes in data only and linked data broadcasting that can be viewed in conjunction with digital broadcasting television and radio programs. In this case, the user can receive information linked to the TV broadcast program or radio broadcast program being viewed and display it on the screen, for example, by operating a linked data display key provided on the remote controller.

  In response to such diversification of broadcast types, Patent Document 1 discloses a digital broadcast receiver that presents received information transmitted by digital broadcast, the operation status of the receiver, and the like in an easy-to-understand manner. The digital broadcast receiver described in Patent Document 1 is shown in FIG. This digital broadcast receiver employs a backlight type liquid crystal display device as the reception information display unit 100 arranged at the front center of the main body, and when receiving the digital broadcast, the resolution and format of the video signal, the television broadcast or the radio broadcast In this configuration, broadcast type identification information such as data broadcast or the like is detected, and the information is taken up by the microprocessor from the receiving unit and the decoding unit, and the emission color of the backlight is variably controlled. Thus, the user can check the broadcast type being viewed (received) by the emission color of the reception information display unit 100.

On the other hand, in recent years, a liquid crystal display device that displays a broadcast video program using a liquid crystal panel as a light receiving type light modulation means instead of a cold cathode fluorescent lamp (CRT) is widely used as a television receiver. It has become. The liquid crystal display device controls the group and orientation of liquid crystal molecules by encapsulating liquid crystal between two transparent substrates provided with electrodes and controlling the voltage to drive electrode units arranged in a matrix. An image is displayed on the liquid crystal panel by changing the transmittance of the irradiation light from the backlight light source provided on the back surface of the transparent substrate.
JP 2001-275051 A

By the way, in general, a screen brightness of about 250 cd / m ² is sufficient for a personal computer (PC) monitor for displaying computer video, whereas a television receiver requires 450 to 500 cd / m ² or more. In particular, in a television receiver (liquid crystal television receiver) using a liquid crystal display device, higher luminance is being promoted by improving a backlight or the like.

  Basically, the brightness level (light emission intensity) of the backlight light source is fixedly set to the content that the user manually adjusts (dimming), and the brightness level is constant regardless of the type of input video signal to be displayed. is there. Therefore, if a television receiver set to high brightness for television image display and displaying a data broadcast image close to a computer image, which is mainly text information, the screen brightness is too high and the display is glaring Therefore, there is a problem that the user's eyes tend to get tired when viewing this for a long time.

  In addition, the power consumption of large-screen liquid crystal display devices is largely accounted for by the power consumption of the backlight unit. From the viewpoint of reducing environmental impact, the power consumption of the backlight unit is reduced. It is hoped to do.

  Here, although the thing of the said patent document 1 is changing the backlight color of the reception information presentation part which presents the information regarding reception, such as a reception channel, according to the broadcast type classification received, the received image | video The screen brightness of the video display unit for displaying data is not considered at all, and there is a problem that it is not possible to reduce fatigue of the eyes of the user or to reduce power consumption.

  The present invention has been made in view of the above problems, and by controlling the screen brightness to an appropriate level according to the type of broadcast to be viewed, it is possible to realize video display that is easier for the user to view and reduce power consumption. It is an object of the present invention to provide a television receiver that can be used.

The first invention of the present application is a receiving means capable of receiving a plurality of different types of broadcasts;
In a television receiver comprising: display means for displaying a program video related to broadcast received by the receiving means; and control means for variably controlling the screen brightness of the display means in accordance with the broadcast type of the program video. The control means is a television receiver that slows down the change rate of screen brightness when switching from screen brightness when displaying program video related to television broadcasting to screen brightness when displaying program video related to data broadcasting It is characterized by.

  According to a second invention of the present application, the plurality of types of broadcasts include at least a television broadcast and a data broadcast, and the control means relates to the data broadcast from a screen luminance when displaying a program video related to the television broadcast. It is characterized in that the screen brightness when displaying the program video is lowered.

According to a third invention of the present application, the plurality of types of broadcasts further include radio broadcasts, and the control means displays the program video related to the radio broadcast based on the screen brightness when displaying the program video related to the data broadcast. It is characterized by lowering the screen brightness when performing.

A fourth invention of the present application is characterized in that the broadcast type of the program video is switched based on a switching instruction from a user.

A fifth invention of the present application is a video display method for displaying program videos related to a plurality of different types of broadcasts, the step of detecting a broadcast type of the displayed program video, and the detected broadcast type Correspondingly, possess a step of variably controlling a screen brightness, a step of variably controlling the screen brightness, the screen brightness when displaying program video of the television broadcast, when displaying the program image according to data broadcast When changing to the screen brightness, the change speed of the screen brightness is slowed .

  According to the television receiver of the present invention, the screen brightness is appropriately controlled according to the broadcast type to be viewed. For example, when displaying the program video related to data broadcasting, the program video related to television broadcasting is displayed. By suppressing the screen brightness as compared with the case where the display is performed, it is possible to display a screen that is easy to see and does not get tired, and to reduce power consumption.

  Hereinafter, an embodiment of a television receiver of the present invention will be described in detail with reference to FIGS. 1 to 8 for a liquid crystal television receiver (hereinafter referred to as a liquid crystal television) with a built-in digital broadcast receiver.

  Here, FIG. 1 is a block diagram showing a schematic configuration of the liquid crystal television of the present embodiment, FIG. 2 is an explanatory diagram showing an example of a broadcast type switching operation in the liquid crystal television of the present embodiment, and FIG. 3 is a liquid crystal television of the present embodiment. FIG. 4 is an explanatory diagram showing an example of a display screen at the time of radio broadcast reception in the liquid crystal television of the present embodiment, FIG. 5 is an explanatory diagram showing operational control in the liquid crystal television of the present embodiment, and FIG. 7 is a flowchart showing operation control in the liquid crystal television of the present embodiment, FIG. 7 is an explanatory diagram showing other operation control in the liquid crystal television of the present embodiment, and FIG. 8 is an explanatory diagram showing an example of a display screen at the time of receiving linked data broadcast. .

  As shown in FIG. 1, the liquid crystal television according to the present embodiment includes a tuner unit 1 that converts a digital modulation signal input from a transmission path (not shown) into an IQ signal, and digitally demodulates the IQ signal and performs error correction processing. A digital demodulation and error correction unit 2 that performs the above, a descrambling unit 3 that decrypts the encryption if the digital signal after the error correction is encrypted, and a multiplexing of the decrypted digital signal It is provided with a demultiplexer / AV decoder unit 4 that separates the MPEG-encoded video / audio signal data and decodes the separated video / audio signal data into a digital signal of the video / audio signal. .

  Also, the audio signal output from the demultiplexer / AV decoder 4 is subjected to predetermined processing and output to a speaker, and the video signal is subjected to predetermined processing (for example, color space conversion processing, IP (Interlace To Progressive) conversion processing, scaling processing, FRC (Frame Rate Conversion) processing, γ correction processing, color correction processing, synchronization detection processing, etc.) and R, G, B signals ( And an LCD driving unit 7 for driving and controlling the source line and the gate line of the liquid crystal display panel 8 based on the image display signal).

  Furthermore, a backlight light source 10 that is disposed behind the liquid crystal display panel 8 and irradiates the liquid crystal display panel 8 and a light source driving unit 9 such as an inverter circuit that drives the backlight light source 10 to emit light are provided. Here, in the liquid crystal television of the present embodiment, either a direct type backlight system or a side edge type backlight system may be used, and the light source 10 is a cold cathode fluorescent lamp (CCFL) that is generally used at present. In addition, a light emitting diode (LED) or the like can be used. Needless to say, the luminance control method of the light source 10 is not limited to voltage (or current) control, and may employ duty control.

  Further, a remote control receiving unit 11 that receives an instruction signal input by a user using a remote control device (remote control) (not shown), and detects and analyzes the instruction signal received by the remote control receiving unit 11, the tuner unit 1, A system control unit 12 that outputs a predetermined control signal to each unit such as the digital demodulation and error correction unit 2, the descrambling unit 3, the demultiplexer / AV decoder unit 4, and the video processing unit 5 is provided. Further, the system control unit 12 generates a backlight control signal to be output to the light source driving unit 9 and performs light emission driving control of the backlight light source 10.

  That is, the system control unit 12 performs program selection by the tuner unit 1 or reception separated by the demultiplexer / AV decoder unit 4 in response to a user instruction regarding a broadcast type such as television broadcasting, radio broadcasting, and data broadcasting. By controlling the broadcast type from the information, the brightness (emission luminance) of the backlight light source 10 is controlled.

  Here, in the liquid crystal television of the present embodiment, the channel selection by the tuner unit 1 can be performed after selecting a desired broadcast type by operating a broadcast type switching key provided on a remote controller (not shown). For example, as shown in FIG. 2, each time the broadcast type switch key is pressed, the television broadcast, the radio broadcast, and the independent data broadcast are sequentially switched to receive the program video related to each type of broadcast. Can watch.

  Therefore, in the liquid crystal television of the present embodiment, the broadcast type to be received can be switched based on a user instruction, and the light source driving unit 9 is controlled in conjunction with the broadcast type switching instruction to The light emission intensity of the light source 10, that is, the screen brightness can be variably controlled. As described above, the reception broadcast type may be determined based on the information from the demultiplexer / AV decoder unit 4, and the light emission intensity of the backlight light source 10, that is, the screen brightness may be variably controlled based on the received broadcast type.

  Next, the screen brightness control operation in the liquid crystal television of this embodiment will be described with reference to the flowchart of FIG. First, when a broadcast type switching key of a remote controller (not shown) is pressed and a broadcast type switching instruction is detected (step 1), it is analyzed whether or not the broadcast type instructed to switch is a television broadcast (step 2). ). When switching to the television broadcast is instructed, it is determined that the program video related to the television broadcast is displayed, and the emission luminance level of the backlight light source 10 is A (A is a preset value) A control signal is output to the light source driver 9 (step 3).

  Further, it is analyzed whether or not the broadcast type instructed to be switched is data broadcasting (step 4). When switching to data broadcasting is instructed, it is determined that a program video relating to data broadcasting is displayed, and the light emission luminance level of the backlight light source 10 is B (B is a preset value, B <A ), A control signal is output to the light source drive unit 9 (step 5).

  As a result, when displaying a program video related to data broadcasting, the screen brightness can be suppressed as compared to displaying a program video related to television broadcasting. Therefore, text information such as program descriptions and news is mainly used. It is possible to reduce the screen brightness to display a screen that is easy to see and not tiring, and to reduce power consumption.

  On the other hand, if the broadcast type instructed to be switched is not data broadcasting as a result of the analysis in step 4, it is determined that the program video related to radio broadcasting is displayed, and the light emission luminance level of the backlight source 10 is C (C is C A control signal is output to the light source drive unit 9 so as to be a preset value and C <B) (step 6).

  As a result, when displaying a program video related to radio broadcasting with relatively low importance of visual information, the screen brightness is further suppressed as compared to displaying a program video related to television broadcasting or data broadcasting. It is possible to realize further reduction in power consumption.

  Here, there are two types of radio broadcasts: radio broadcasts that allow users to view images and linked data, and radio broadcasts that use only audio. A radio broadcast program that can display images and linked data is selected. If received, the light source drive unit 9 may be controlled so that the light emission luminance level of the backlight source 10 becomes B, for example, as in the case where data broadcasting is selectively received.

  In addition, when a radio broadcast only with sound is selectively received, the backlight source 10 may be completely turned off to reduce power consumption, but the user is not mistaken for a malfunction of the device. Therefore, the light emission luminance level of the backlight light source 10 is sufficiently lowered, and is presented to the user by an OSD (ON Screen Display) display indicating that a radio broadcast of only sound is being received as shown in FIG. Is desirable. In this case, by turning on only the light sources corresponding to a part of the OSD-displayed screen area (the lower right area in the case of FIG. 4), the light sources corresponding to the other screen areas are turned off. It is possible to prevent excessive power consumption.

  As described above, in this embodiment, the backlight luminance is controlled so that the received program video is displayed with an appropriate screen luminance according to the broadcast type for which the user has made a selection instruction. It is possible to display a screen that is easy to see and not tiring, and to reduce power consumption. In particular, it is appropriate for each mode by variably controlling the light emission luminance of the backlight light source in conjunction with a switching instruction between a mode for displaying a program video for television broadcasting and a mode for displaying a program video for data broadcasting. Screen brightness can be obtained.

  By the way, when the screen brightness is changed abruptly at the same time as switching the viewing broadcast type, especially when switching from the mode for displaying program video for TV broadcasting to the mode for displaying program video for data broadcasting, If the screen brightness decreases, the user feels uncomfortable.

  Therefore, in the present embodiment, as shown in FIG. 5, the screen is actually displayed from the time T1 when an instruction to switch from the mode for displaying the program video for television broadcasting to the mode for displaying the program video for data broadcasting is made. The change in the screen brightness is given to the user by slowing the change speed of the screen brightness (increasing the time constant and slowly changing the screen brightness) by multiplying a sufficient time t until the brightness level reaches B. The feeling of strangeness is eased.

  Note that even if the screen brightness increases when switching from the mode for displaying program video related to data broadcasting to the mode for displaying program video related to television broadcasting, it does not give the user a sense of incongruity. The time until the screen brightness level actually reaches A is shortened from the time T2 when the instruction to switch from the mode for displaying the program video to the mode for displaying the program video related to the television broadcast is made, and immediately increases. It is desirable to present a TV image with brightness.

  Further, in the present embodiment, in addition to the automatic screen brightness control linked to the broadcast type selected for reception, the screen brightness adjustment control by the user is also possible. This will be described with reference to the flowchart of FIG. When a dimming key on a remote controller (not shown) is pressed and a dimming instruction is detected by the user (step 1), a dimming setting OSD (ON Screen Display) is displayed on the edge of the screen. The user can instruct to increase or decrease the screen brightness by pressing the up / down direction key of the remote control while viewing the OSD screen for dimming setting.

  When the up key of the remote control is pressed and an instruction to increase the luminance is given (step 2), the emission luminance level of the backlight source 10 becomes a value obtained by adding one step to the light source luminance level at that time. Then, a control signal is output to the light source driving unit 9 (step 3). On the other hand, when the down key of the remote controller is pressed to instruct the brightness reduction (step 4), the light emission brightness level of the backlight source 10 is a value obtained by subtracting one step from the light source brightness level at that time. Thus, a control signal is output to the light source drive unit 9 (step 5).

  Thereby, the user can arbitrarily adjust the screen brightness automatically set according to each broadcast type according to the usage environment, display video content, and the like, and the merchantability can be further improved.

Furthermore, an illuminance sensor that detects the brightness of the surrounding environment of the device may be provided, and the screen luminance may be determined from the detection result of the illuminance sensor and the received broadcast type. For example, as shown in FIG. 7, in the mode for displaying a program image related to television broadcasting, the light emission luminance level of the light source 10 is A ₁ when the ambient illuminance is bright, and the light source 10 emits light when the ambient illuminance is within the standard range. When the brightness level is A ₂ and the ambient illuminance is dark, the light emission brightness level of the light source 10 is A ₃ (A ₁ > A ₂ > A ₃ ), and the ambient illuminance is set in the mode for displaying the program video related to data broadcasting. When the brightness is bright, the light emission luminance level of the light source 10 is B ₁ , when the ambient illuminance is within the standard range, the light emission luminance level of the light source 10 is B ₂ , and when the ambient illuminance is dark, the light emission luminance level of the light source 10 is B ₃ ( _{B 1> B 2> B 3} ).

Further, in the display mode when the radio broadcast is selected, C ₁ emission luminance level of the light source 10 when the ambient illuminance is bright, the light emission luminance level of the light source 10 when the ambient illuminance is within the normal range C ₂ When the ambient illuminance is low, the light emission luminance level of the light source 10 is C ₃ (C ₁ > C ₂ > C ₃ ).

  Thereby, according to the brightness of the viewing environment, it is possible to automatically control to the optimum screen brightness in the display mode linked to each broadcast type, so that the merchantability can be further improved.

  The data broadcasting described above includes independent data broadcasting that specially broadcasts only data, and linked data broadcasting that can be viewed in conjunction with digital broadcasting television and radio programs. In this case, the user can receive information linked to the TV broadcast program or radio broadcast program being viewed and display it on the screen, for example, by operating a linked data display key provided on the remote control.

  For example, while viewing a TV broadcast program, the OSD (ON Screen Display) display indicating that data is being acquired is displayed by pressing the linked data display key. It is possible to switch to the display screen of the data broadcast program having the TV broadcast program video. In this case as well, the light emission luminance of the backlight light source 10 may be controlled so that the screen luminance level becomes B.

  In addition, when a backlight light source that can change the light emission brightness for each screen area is used, the light emission brightness of the light source corresponding to the sub-screen area for displaying the TV broadcast program image being viewed is increased to perform data broadcasting. The light emission luminance of the light source corresponding to the other screen area displaying the program video may be lowered.

  Further, in the above-described embodiment of the present invention, in order to realize a sharp feeling when displaying a moving image, the emission luminance of the backlight source 10 according to the screen feature amount such as APL (average luminance level) of each frame. May be variably controlled dynamically. In this case, the maximum light emission luminance of the backlight light source 10 may be set according to the broadcast type of the program video to be displayed.

  In the embodiment of the present invention, the direct-view type liquid crystal display device has been described. However, the present invention may be applied to a projection type liquid crystal display device. It is obvious that the present invention may be applied to a video display device that displays an image by using or other video display devices. Furthermore, it is needless to say that the input switching setting by the user is not limited to the configuration performed by operating the remote controller, but may be configured by operating an operation member (not shown) provided in the apparatus main body.

  Furthermore, in the above-described embodiment of the present invention, a television receiver having a built-in digital broadcast receiving unit has been described. However, the present invention is not limited to this, and a case where an image received by an external digital broadcast receiving unit is displayed. Also, the broadcast type of the program video to be displayed is detected from the contents of the user instruction to the external digital broadcast receiving means and the information related to the reception from the external digital broadcast receiving means, and the screen brightness is variably controlled based on the detection result. You may make it do.

It is a block diagram which shows schematic structure in one Embodiment of this invention. It is explanatory drawing which shows the example of switching operation | movement of the broadcast type in one Embodiment of this invention. It is a flowchart which shows the control action in one Embodiment of this invention. It is explanatory drawing which shows the example of a display screen at the time of radio broadcast reception in one Embodiment of this invention. It is explanatory drawing which shows the operation control in one Embodiment of this invention. It is a flowchart which shows the control action in one Embodiment of this invention. It is explanatory drawing which shows the other control action in one Embodiment of this invention. It is explanatory drawing which shows the example of a display screen at the time of linked data broadcast reception. It is (a) external view and (b) principal part enlarged view which shows the conventional digital broadcast receiver.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tuner part 2 Digital demodulation and error correction part 3 Descramble part 4 Demultiplexer and AV decoder part 5 Audio | voice processing part 6 Video processing part 7 LCD drive part 8 Liquid crystal display panel 9 Light source drive part 10 Backlight light source 11 Remote control receiver 12 System controller

Claims (5)

Receiving means capable of receiving a plurality of different types of broadcasts;
Display means for displaying a program video related to the broadcast received by the receiving means ;
In a television receiver comprising control means for variably controlling the screen brightness of the display means according to the broadcast type of the program video,
The control means slows the change rate of the screen brightness when switching from the screen brightness when displaying the program video related to the television broadcast to the screen brightness when displaying the program video related to the data broadcast. TV receiver. The plurality of types of broadcasting includes at least television broadcasting and data broadcasting,
2. The television according to claim 1, wherein the control means lowers the screen brightness when displaying the program video related to data broadcasting from the screen brightness when displaying the program video related to television broadcasting. Receiver. The plurality of types of broadcasts further include radio broadcasts,
The said control means reduces the screen brightness at the time of displaying the program image | video concerning radio broadcasting from the screen brightness | luminance at the time of displaying the program image | video concerning data broadcasting, The said 1 or 2 characterized by the above-mentioned. Television receiver. Based on the switching instruction from the user, the television receiver according to any one of claims 1 to 3, characterized in that switched broadcast type of the program video. A video display method for displaying program videos related to different types of broadcasts,
Detecting a broadcast type of the displayed program video;
Depending on the detected broadcast type, the screen brightness possess a step of variably controlling,
The step of variably controlling the screen brightness slows down the change speed of the screen brightness when switching from the screen brightness when displaying the program video related to television broadcasting to the screen brightness when displaying the program video related to data broadcasting. A video display method characterized by:

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