JP2008309967A - Monitor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a "monitor device" capable of effectively reducing duzzle of the whole image according to ambient conditions even when the image to be displayed includes a picture part. <P>SOLUTION: The monitor device 10 includes a display means 12, an external light detecting means 17, an image converting means 15 of mixing a black-and-white image with the image to be displayed at a predetermined blending rate and outputting the resulting image, and a display control means 11. Under the control of the display control means 11, the image converting means 15 varies the predetermined blending rate according to ambient lightness detected by the external light detecting means 17 and outputs the image obtained through mixing at the blending rate to the display means 12, so that the image is displayed on its screen. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a monitor device, and more particularly to a technique useful for reducing glare of an image displayed on a display screen in a monitor device having a dimming function that automatically adjusts the brightness of the display screen according to external light.

  A vehicle such as an automobile or a train is equipped with a monitor device such as a display having a display screen for providing various kinds of guidance information to passengers. For example, in-vehicle LCD (liquid crystal) displays are equipped with a function (automatic light control function) that adjusts the brightness of the backlight of the LCD according to the ambient brightness in order to make the display screen easier to see. . This is because an ambient light sensor is provided in the vicinity of the monitor screen, the ambient light intensity is detected by the ambient light sensor, and a control signal for adjusting the brightness of the backlight according to the degree of the illumination intensity is generated. By supplying a control signal to the inverter and driving the backlight by PWM (pulse width modulation) control, the light emission amount (brightness of the display screen) is changed.

  In particular, the monitor screen looks dazzling when the surroundings are dark (such as at night or in bad weather). Therefore, in order to reduce the glare and make the screen easier to see, the vehicle lighting information (hereinafter referred to as “dimmer information” for convenience) In general, a technique (automatic light control) that automatically changes the brightness of the backlight of the monitor on the basis of the above is also known.

  Similarly, as another technique for reducing glare, a technique for changing the color of an image itself based on dimmer information has also become common. For example, when displaying a map image on the monitor screen of the navigation device, the display color of the map image is changed depending on whether the surroundings are bright (such as daytime) or dark (such as nighttime).

As a technique related to the conventional technique, for example, as described in Patent Document 1, a liquid crystal display device that performs dimming of a backlight disposed on the back surface of a liquid crystal display unit using a current dimming inverter The display brightness of the display data on the liquid crystal display unit is controlled by changing the display data to be displayed on the liquid crystal display unit according to an external instruction so as to lower the gradation of the display data.
Japanese Patent Laid-Open No. 11-194736

  As described above, in the conventional technique, as a technique for reducing the glare of the monitor screen, a technique for automatically adjusting the backlight of the monitor based on dimmer information and a technique for changing the color of the image to be displayed are practical. It has become.

  However, the technology for changing the brightness of the backlight merely adjusts the amount of light emission (brightness of the display screen) and does not change the color of the image to be displayed. In the case of a bright color close to the primary color, the image corresponding to the bright color looks dazzling. Such a phenomenon appears remarkably in a dark environment such as at night. That is, there is a problem that the dazzle of the monitor screen cannot always be effectively reduced only by automatically adjusting the backlight.

  Therefore, a technique for changing the color of the image to be displayed as described above, for example, a technique for reducing glare by using a relatively dark color instead of a bright color has been put into practical use.

  However, in the current technology for changing the color of the image itself, the display color is changed only for an image created inside the product (for example, an image generated in the navigation device), for example, acquired from the outside The color of the image data such as the picture was not changed. Therefore, even if the entire image for one screen is dark, there is a problem that the picture portion looks dazzling.

  The present invention was created in view of the problems in the prior art, and effectively reduces glare of the entire image according to the surrounding situation even when a picture portion is included in the image to be displayed. An object of the present invention is to provide a monitor device capable of performing

  In order to solve the above-mentioned problems of the prior art, according to the basic form of the present invention, a display means having a screen, an outside light detection means arranged in the vicinity of the screen and detecting ambient brightness, a display An image conversion unit having a function of mixing and outputting a black and white image to a target image at a predetermined blend rate, and changing the predetermined blend rate according to the ambient brightness detected by the external light detection unit And a display control unit that controls to display an image mixed and output at the blend ratio on the screen of the display unit.

  According to the monitor device of this embodiment, the image conversion unit mixes the black and white image with the predetermined blend ratio in the image conversion unit based on the control from the display control unit, and the mixture is performed. The image (blend image) is output to the display means and displayed on the screen. At this time, the blend image output from the image conversion unit to the display unit exhibits an intermediate color between the original image and the monochrome image (a darker color than the original bright color). Accordingly, since the image displayed on the screen of the display means is displayed in an intermediate color, the glare can be effectively reduced. This contributes to reduction of glare of the entire image.

  In addition, since the predetermined blend rate that is a reference when performing the image conversion process is controlled to be changed according to the ambient brightness detected by the external light detection unit, the display according to the surrounding situation is performed. Images can be provided.

  In order to solve the above-described problems of the prior art, according to another aspect of the present invention, a display unit having a screen and an outside light detection unit that is arranged in the vicinity of the screen and detects ambient brightness And an image conversion unit having a function of directly converting a pixel value for each pixel and converting the image to be displayed into an image of a predetermined intermediate color, and the surroundings detected by the external light detection unit And a display control means for controlling the predetermined intermediate color to be changed according to the brightness of the display and for controlling the image converted to the intermediate color to be displayed on the screen of the display means. An apparatus is provided.

  Also in the monitor device according to this embodiment, as in the monitor device according to the above-described embodiment, an image to be displayed is converted into a predetermined intermediate color image and displayed on the screen of the display means. The glare can be effectively reduced. In addition, since the predetermined intermediate color is controlled to be changed according to the ambient brightness, it is possible to provide a display image according to the surrounding situation.

  Other structural features of the monitoring apparatus according to the present invention, advantages based thereon, and the like will be described with reference to the embodiments of the invention described below.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing the configuration of an in-vehicle monitor device having a picture conversion function according to an embodiment of the present invention. The monitor device 10 of this embodiment is connected to other video sources that supply video information, for example, other in-vehicle devices such as audio / video (A / V) devices and navigation devices, and to this device 10 as necessary. Used with external media devices.

  As shown in FIG. 1, the in-vehicle monitor device 10 according to this embodiment includes a display control unit 11, a display unit (for example, a liquid crystal panel) 12 that provides information via a screen, and a screen of the display unit 12. A backlight 13 (for example, a cold cathode fluorescent lamp (CCFL) used as a light source) that irradiates light from the back side and gives a required luminance to the display screen, and a backlight 13 based on control from the display control unit 11 An inverter 14 driven by PWM control, a picture conversion unit 15 characterizing the present invention, an image generation unit 16 that generates an image to be displayed based on control from the display control unit 11, and a predetermined position of the monitor device 10 The external light sensor 17 provided in the display and a signal (analog signal) corresponding to the ambient brightness (light quantity) detected by the external light sensor 17 are converted into a digital signal, and the display control unit 1 An A / D converter 18 to be output to, and an operation portion 19. In addition, video information (image data) is appropriately input to the display control unit 11 from a video source such as another in-vehicle device or an external media device. Of course, the image data acquired from the outside includes a picture portion.

  FIG. 2 schematically shows an external configuration when the monitor device 10 of the present embodiment is viewed from the front surface (front panel). As shown in the figure, the device 10 is incorporated as a part of an A / V device on which a disk medium can be mounted so as to constitute a monitor portion thereof, so that both the driver and the passenger on the front passenger seat can be shared in the passenger compartment. It is installed in the form of being embedded in the middle center console (with its front panel exposed). In FIG. 2, 1 is a display screen of a liquid crystal panel (display unit 12), 2 is an open / close button for bringing the liquid crystal panel 12 out of the center console (OPEN), and storing it inside (CLOSE), 3 is a CD or the like A disk insertion slot 4 for loading a disk such as a DVD indicates an “eject” button for taking out the disk loaded in the disk insertion slot 3. Further, as shown in the figure, the outside light sensor 17 is disposed at a substantially central portion of the front panel below the liquid crystal panel 12 in the “OPEN” state, and an operation unit 19 is disposed on the left side thereof.

  The operation unit 19 is an interface for inputting a user instruction necessary for operating the monitor device 10, and includes various operation buttons and the like as illustrated in FIG. As a form of the operation unit 19, in addition to the “operation panel” as illustrated, for example, a “remote control” connected to the display control unit 11 by infrared communication, or the liquid crystal panel 12 for convenience of operation. It may be a “touch panel” arranged on the screen.

  Although not shown in particular in the external configuration of FIG. 2, a connector for connecting a portable media device: PMD (Portable Media Device) via a USB cable or the like is provided. An example of PMD is iPod (registered trademark), which has recently been in the spotlight. In the case of iPod, a music file distributed via the Internet or the like is once downloaded to a personal computer (PC), and the iPod is downloaded from this PC. You can listen to music files (music) checked out (transferred) with an earphone. When this is applied to an in-vehicle device, the iPod is further connected to the above connector via a USB cable or the like, and the music file data stored in the iPod is taken into the A / V device and reproduced and output. The music can be listened to through a speaker (not shown), and information related to the music file on the screen of the liquid crystal panel 12 (character information such as song name, artist name, album name, A face photograph (picture) etc. can be visually recognized. In addition to the character information and pictures described above, information related to various operation instructions input via the operation unit 19 and operation screens are also displayed on the screen of the liquid crystal panel (display unit 12).

  Referring to FIG. 1, a picture conversion unit 15 characterizing the present invention includes a black and white conversion unit 15a and a blend processing unit 15b. The black and white conversion unit 15a is a functional block that converts the display target picture data (original color image) supplied from the display control unit 11 into a black and white image, and the blend processing unit 15b is converted through the black and white conversion unit 15a. This is a functional block that inputs a black and white image and picture data (original color image) supplied from the display control unit 11, and mixes and outputs the black and white image to the color image according to a predetermined blend ratio described later. This blend ratio is variably set according to the external light (dimer information) detected by the external light sensor 17. That is, the picture conversion unit 15 as a whole has a function of performing a predetermined blend process (picture conversion process) according to dimmer information based on the control from the display control unit 11.

  The picture data converted through the picture conversion unit 15 in this way (color image data subjected to the blending process) is input to the image generation unit 16 and the image data other than the picture part supplied from the display control unit 11 The combined data is supplied to the display unit 12 as display data and displayed on the screen.

  The display control unit 11 basically controls the entire processing for displaying various types of information performed by the monitor device 10, and as processing related to the present invention, as will be described later, Control for changing the color (tone) of the (picture data) according to the external light (dimer information) detected by the external light sensor 17 is performed. Furthermore, it also has a function of performing luminance adjustment (automatic light control processing) of the backlight 13 in accordance with external light (dimer information) detected by the external light sensor 17. The display control unit 11 includes a ROM that stores a program that defines processing relating to image display, a RAM that temporarily stores data necessary for the processing, and the like.

  In this RAM, as information related to the present invention, blend ratio information (degree of dimmer) set in a plurality of stages according to the degree of ambient brightness (degree of dimmer) detected in advance by the external light sensor 17 is stored. And a table representing the relationship between the blend ratio and the blend ratio, and is referred to when a required blend process (picture conversion process) is performed in accordance with external light as described later. Further, the RAM also stores a table representing the relationship between the degree of dimmer and the appropriate dimming rate (brightness of the backlight 13) corresponding to the degree of dimmer, and necessary brightness adjustment according to the external light as will be described later. Referenced when performing (automatic light control processing). In this embodiment, both the “picture conversion process” table and the “automatic light control process” table are stored in the RAM in the display control unit 11, but at least the “picture conversion process” table is stored. The information may be incorporated in the blend processing unit 15b that directly uses the information.

  FIG. 3 shows an example of this “picture conversion process” table (relationship between the degree of dimmer and the blend ratio). Here, the blend ratio refers to a ratio (%) of the entire black and white image to be blended (original color image + monochrome image). In the example of FIG. 3, the “dimmer degree (%)” is set in four stages (0 to 20, 20 to 50, 50 to 80, and 80 to 100), and according to the respective dimmer degree (%). “Blend rate (%)” is set to 80%, 60%, 40%, and 0%.

  In the in-vehicle monitor device 10 configured as described above, the display control unit 11 is a “display control unit”, the display unit 12 is a “display unit”, the backlight 13 is a “luminance application unit”, and a picture conversion unit. Reference numeral 15 corresponds to “image conversion means”, and the external light sensor 17 corresponds to “external light detection means”.

  Next, a picture conversion process (blend process) performed in the in-vehicle monitor device 10 according to the present embodiment will be described with reference to FIG.

  First, when the display control unit 11 inputs picture data (original color image) to be displayed to the black and white conversion unit 15a and the blend processing unit 15b, the black and white conversion unit 15a converts the input color image into a black and white image. And the converted black and white image is output to the blend processing unit 15b.

  FIG. 4A shows an example of picture data (original color image) to be displayed and a monochrome image. In the illustrated example, for simplification of description, the image of the picture part is composed of 3 × 3 = 9 pixels, and each pixel is obtained from pixel values of three primary colors (R = red, G = green, B = blue). The case where it is configured is shown. For example, when attention is paid to the second column from the top of the original color image, the left pixel defines “red” having pixel values of R = 100, G = 0, and B = 0, and the central pixel is R ”0”, “G = 100”, and B = 0 are defined as “green”, and the right pixel is defined as “R = 0, G = 0, B = 100” that is “blue”. Yes.

  On the other hand, for a black and white image, the three pixel values of each pixel are the same value (R = G = B) in order to define a monotone (single color). For example, when attention is paid to the three pixels in the second column from the top of the monochrome image, the pixel value of the left pixel is R = G = B = 30, the pixel value of the center pixel is R = G = B = 59, The pixel value of the pixel is R = G = B = 11, and the shade of black is darker in the order of center <left side <right side.

  Next, in the blend processing unit 15b to which the original color image and the monochrome image are input, in accordance with the degree of ambient brightness (dimer information) detected by the external light sensor 17 in cooperation with the display control unit 11. To specify the blend ratio. At this time, when the table for “picture conversion processing” illustrated in FIG. 3 is built in the blend processing unit 15b, the dimmer information (degree of dimmer) notified from the display control unit 11 in the blend processing unit 15b. ), The “blend rate” corresponding to the “degree of dimmer” is specified from the table. On the other hand, when the table is stored in the RAM in the display control unit 11, the display control unit 11 specifies the “blend rate” corresponding to the “degree of dimmer” from the table, and specifies the specification. Information on the “blend rate” is notified to the blend processing unit 15b. When the “blend rate” is specified in the blend processing unit 15 b as described above, the black and white image is blended with the original color image according to the blend rate and is output to the image generation unit 16.

  The picture data (blend image) converted through the blend processing unit 15b exhibits an intermediate color between the “original color image” and the “monochrome image” as shown in FIG. Here, the right side of FIG. 4 (a), FIG. 4 (b) and FIG. 4 (c) show blend images obtained by mixing at blend ratios of 80%, 60% and 40%, respectively. Further, the blend image in FIG. 4D shows a case where the blend rate is 0% (that is, a black and white image is not included).

  For example, when the picture conversion process is performed at a blend rate of 60% (see FIG. 4B), when attention is paid to the second column of the blend image, the left pixels are R = 58, G = 18, B = The middle pixel presents an “intermediate color” defined by 18 pixel values, the middle pixel exhibits an “intermediate color” defined by R = 35, G = 75, and B = 35 pixel values, and the right pixel represents R = 35. 6. Presents an “intermediate color” defined by pixel values of G = 6, B = 46. Note that the pixel value of R = 58 is R = 30 (monochrome image) × 60% and R = 100 (color image) × 40% from the “original color image” and “monochrome image” in the same second column. The other pixel values are obtained by the same calculation.

  Although it is not a process that characterizes the present invention, a detailed description thereof is omitted. In parallel with the picture conversion process (blend process) described above, external light (dimer) detected by the external light sensor 17 by the display control unit 11 is described. Automatic dimming processing according to information) is also performed. That is, the display control unit 11 receives a signal (dimer information) corresponding to the amount of external light detected by the external light sensor 17 via the A / D converter 18 and stores the “automatic light control” stored in the RAM. Referring to the table for “processing”, the dimming rate corresponding to the amount of the external light is specified, and the backlight 13 is adjusted via the inverter 14 with the light emission amount (luminance) corresponding to the dimming rate. It is carried out. Such brightness adjustment (automatic light control processing) is the same as that of the conventional type.

  As described above, according to the in-vehicle monitor device 10 (FIG. 1) according to the present embodiment, the picture data to be displayed (original color image) in the picture conversion unit 15 based on the control from the display control unit 11. A black and white image is mixed at a predetermined blend ratio (FIG. 3) to convert it to an intermediate color image (a darker image than the original bright color), and the converted picture data (an intermediate color image) is converted into an image. The data is supplied as display data to the display unit 12 via the generation unit 16 and displayed on the screen. Thereby, the image of the picture portion displayed on the screen of the display unit 12 (the right side of FIG. 4A, the blend image shown in FIGS. 4B and 4C) is displayed in an intermediate color. It is possible to effectively reduce the glare and thus contribute to the reduction of the glare of the entire image. Furthermore, since the degree of light and dark gradation of the blend image does not change, the image is easy to identify.

  For comparison, FIG. 5 shows an image in which the backlight luminance is simply reduced (an image in the picture portion is composed of 3 × 3 = 9 pixels). In the example shown in the figure, an image when the luminance is reduced by 20% is shown, and since it is dark as a whole, the glare is alleviated, but since there is no light and dark gradation, the image is difficult to identify. ing.

  In addition, the blend rate that serves as a reference when performing blend processing (FIG. 4) in the picture conversion unit 15 is controlled by the display control unit 11 so as to be changed according to the degree of dimmer (degree of ambient brightness). Therefore, it is possible to provide a display image according to the surrounding situation (brightness).

  In the above-described embodiment (FIG. 1), the case where the picture conversion function characterizing the present invention is configured by hardware (picture conversion unit 15) has been described as an example. However, the means for realizing the picture conversion function is not limited to this. Of course, it can also be realized by software processing, for example. An embodiment in that case is shown in FIG.

  FIG. 6 shows the configuration of an in-vehicle monitor device according to another embodiment of the present invention. Similar to the above-described embodiment, other video sources for supplying video information (other in-vehicle devices and Used with external media equipment, etc.) Therefore, video information (image data including a picture portion) is appropriately input from the video source to the display control unit 11a.

  The in-vehicle monitor device 10a according to the present embodiment, compared with the in-vehicle monitor device 10 according to the above-described embodiment (FIG. 1), performs picture conversion realized by software processing instead of the picture conversion unit 15 as hardware. The difference is that the unit 20 is built in the display control unit 11a. The picture conversion unit 20 calculates a blend rate (FIG. 3) from the detection signal (dimer information) of the external light sensor 17 acquired by the display control unit 11a, and displays display target picture data (original color) according to the blend rate. Calculation and conversion for blending a black and white image to (image) are performed, and the converted picture data is output to the image generation unit 16. Other configurations and operations (functions) thereof are the same as those in the above-described embodiment, and thus description thereof is omitted.

  Even in the in-vehicle monitor device 10a according to the present embodiment, the picture conversion function is converted by blend processing as in the case of the above-described embodiment, although there is a difference between realization by hardware and software processing. The intermediate color image (the darker color image than the original bright color) is displayed on the screen of the display unit 12, and the blend ratio is changed and controlled according to the degree of dimmer. Accordingly, it is possible to effectively reduce the glare of the entire image.

  Further, in each of the above-described embodiments, the display target picture data (original color image) is converted into an intermediate color image by performing blend processing, and the intermediate color image is displayed on the screen of the display unit 12. However, as is apparent from the gist of the present invention, it is not always necessary to perform blending as a means for obtaining an intermediate color image. For example, a predetermined intermediate color image may be obtained by directly performing pixel value conversion processing for each pixel on the display target picture data (original color image). Even if this method is used, the same effects as those of the above-described embodiments can be obtained.

  Further, in each of the above-described embodiments, the case where the monitor device according to the present invention is applied to a vehicle is described as an example. However, as is apparent from the gist of the present invention, the monitor device according to the present invention is not necessarily applied to a vehicle. Of course, it is not necessary to be mounted. In short, as described above, means for detecting external light, means for changing the hue (color tone) of an image to be displayed (including a picture portion) according to external light, and a display screen according to external light. It suffices to have means for adjusting the brightness, and the present invention is not limited to in-vehicle use as long as it is a monitor device provided with such means. The present invention can be similarly applied to various monitor devices used.

It is a block diagram which shows the structure of the vehicle-mounted monitor apparatus provided with the picture conversion function which concerns on one Embodiment of this invention. It is a figure which shows schematically the external appearance structure when the monitor apparatus of FIG. 1 is seen from the front surface (front panel). It is a figure which shows an example of the table (Relationship between the degree of a dimmer and a blend rate) stored in RAM in the display control part in FIG. It is a figure which shows an example of the image for demonstrating the picture conversion process (blend process) performed based on the table of FIG. It is a figure which shows an example of the image which reduced only the brightness | luminance of the backlight. It is a block diagram which shows the structure of the vehicle-mounted monitor apparatus provided with the picture conversion function which concerns on other embodiment of this invention.

Explanation of symbols

1 ... Display screen,
10, 10a ... In-vehicle monitor device,
11, 11a ... display control unit (display control means),
12 ... display part (display means),
13 ... Backlight (luminance applying means),
14 ... an inverter,
15, 20 ... Picture conversion unit (image conversion means),
15a: black and white conversion section,
15b ... Blend processing unit,
16 ... image generation unit,
17: External light sensor (external light detection means).

Claims (7)

Display means having a screen;
Outside light detection means that is disposed in the vicinity of the screen and detects ambient brightness;
An image conversion means having a function of mixing and outputting a black and white image with a predetermined blend ratio to an image to be displayed;
Control is performed to change the predetermined blend ratio according to the ambient brightness detected by the external light detection means, and control is performed to display an image mixed and output at the blend ratio on the screen of the display means. A monitor device comprising display control means.   The image conversion means includes a black and white conversion unit that converts an input color image into a black and white image, and a blend processing unit that mixes the converted black and white image into the color image in accordance with the predetermined blend ratio. The monitor device according to claim 1.   2. The monitor apparatus according to claim 1, wherein the display control unit includes the image conversion unit, and realizes a function of the image conversion unit by software processing. Display means having a screen;
Outside light detection means that is disposed in the vicinity of the screen and detects ambient brightness;
An image conversion unit having a function of directly converting a pixel value for each pixel and converting the image to be displayed into an image of a predetermined intermediate color;
Display control means for controlling the predetermined intermediate color to be changed according to the ambient brightness detected by the external light detection means, and for controlling the image converted to the intermediate color to be displayed on the screen of the display means. And a monitor device.   5. The monitor apparatus according to claim 1, wherein the image to be displayed input to the image conversion means is an image including a picture portion acquired from the outside. Furthermore, a luminance applying means for giving a required luminance to the screen of the display means is provided,
The monitor device according to claim 1, wherein the display control unit performs control so as to change the required luminance in accordance with ambient brightness detected by the outside light detection unit.   The monitor device according to claim 1, wherein the monitor device is mounted on a vehicle.

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