JP2013150217A - Correction device, correction method and television receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a correction device capable of displaying a video image corresponding to an observation direction of a display without giving a stress to a user.SOLUTION: A correction device comprises a gamma correction section 20. When a predetermined user operation is performed using a remote controller 2, the gamma correction section 20 is switched to a correction mode. In the correction mode, a video signal to be supplied to a display panel 50 is outputted after performing gamma correction thereon in accordance with a gamma curve for correcting the video signal in such a manner that a luminance obtained by observing a display in a specific direction different from the front is made closer to a luminance obtained by observing the display panel 50 from the front.

Description

  The present invention relates to a correction device for correcting a video signal and a correction method of such a correction device. The present invention also relates to a television receiver including such a correction device.

  In recent years, with the expansion of the market for flat-screen televisions, it has become possible to watch and enjoy high-quality digital broadcasts at various locations including ordinary homes. In addition, places where users view, viewing scenes, viewing styles, etc. are changing. For example, in a living room, kitchen, or bedroom in a general home, you can watch TV directly in front of you. The viewing style to do has also increased.

  In such a background, a liquid crystal display device including a liquid crystal display (LCD), a PDP display device including a plasma display (PD), and an EL display device including an EL (Electro Luminescence) display In a display device equipped with an FPD (Flat Panel Display) represented by the above, in addition to the viewing angle characteristics of the display included in each display device, the viewing environment such as reflection of external light from the surface glass, ambient brightness, etc. There is a problem that it becomes difficult to see the display image displayed on the display when viewing at a position shifted from the front of the display due to changes.

  In particular, in a liquid crystal display device, depending on the viewing angle characteristics of the display, the contrast of the displayed image is reduced, the gradation is crushed, the black-and-white reversal phenomenon, and the color (the hue, saturation, and brightness are the three elements of color). ) May occur.

  A viewing angle characteristic of a general liquid crystal display will be described with reference to FIG. FIG. 8 is a graph showing a general characteristic of light transmittance with respect to an angle (polar angle, viewing angle) from a direction perpendicular to the front of the display.

  As shown in FIG. 8, the lower the angle from the direction (0 °) perpendicular to the front of the display is, the lower the transmittance is, and the display appears darker.

  Further, FIG. 9 shows the characteristics of the output luminance with respect to the input voltage to the pixels included in the display when the display is viewed from the front and when viewed from 30 ° below the front. FIG. 9 is a diagram illustrating a general characteristic of output luminance with respect to an input voltage to a pixel included in the display.

  As shown in FIG. 9, even when the same voltage is applied to the pixels when the display is viewed from 30 ° below the front (curve Y) than when the display is viewed from the front (curve X), Output brightness from the display is low. That is, the image displayed on the display looks darker when viewed from 30 ° below the front than when viewed from the front.

  On the other hand, the applicant applies a liquid crystal display device that automatically performs gamma correction on an input signal based on gamma correction data selected based on the detection result of the viewing angle detection means for detecting the viewing angle with respect to the liquid crystal display element. (Patent Document 1).

Japanese Patent Laid-Open No. 10-301092 (published on November 13, 1998)

  However, in the technique described in Patent Document 1, gamma correction is automatically performed, so that the appearance of the image changes at a timing not intended by the user. For this reason, there was a problem of giving stress to the user.

  The present invention has been made to solve the above-mentioned problems, and its main purpose is to flexibly cope with changes in viewing styles such as the installation location of the display and the wall-hanging style, without causing stress. An object of the present invention is to provide a correction apparatus capable of displaying an image corresponding to an observation direction.

  In order to solve the above problems, the correction device according to the present invention brings the luminance obtained by observing the display from a specific direction different from the front to be close to the luminance obtained by observing the display from the front. A storage unit for storing gamma curve data representing a gamma curve for correcting a video signal supplied to the display; and a gamma correction unit for correcting the video signal supplied to the display, wherein a predetermined unit using an input device is used. A gamma correction unit that refers to the gamma curve data stored in the storage unit when a user operation is performed, and switches to a correction mode in which the video signal supplied to the display is output by performing gamma correction according to the gamma curve; It is characterized by having.

  In order to solve the above problems, the correction method of the correction device according to the present invention converts the luminance obtained by observing the display from a specific direction different from the front to the luminance obtained by observing the display from the front. A reading step for reading out gamma curve data representing a gamma curve for correcting the video signal supplied to the display so as to approach the storage unit, and an operation mode of the gamma correction unit for correcting the video signal supplied to the display are input. When a predetermined user operation using the apparatus is performed, the gamma curve data read in the reading step is referred to, and a video signal supplied to the display is gamma-corrected according to the gamma curve and output. And a switching step for switching.

  According to the above configuration, the gamma correction unit displays the brightness obtained by observing the display from a specific direction different from the front when the predetermined user operation using the input device is performed. Gamma correction is performed so as to approximate the brightness obtained by observation from the above. In other words, the gamma correction unit performs gamma correction so that the luminance represented by the video signal approaches the luminance when the display is viewed from the front, in accordance with the direction in which the user views the display. Therefore, the correction device can flexibly cope with changes in viewing styles such as the installation location of the display and the wall hanging style.

  As a result, the user simply performs a predetermined operation (for example, pressing a predetermined button) using the input device from a specific direction different from the front of the display. The video can be viewed with a brightness close to the brightness.

  The gamma correction unit switches the operation mode of the gamma correction unit 20 only when a predetermined user operation using the input device is performed. For this reason, since the display device 1 does not automatically switch the operation mode according to the viewing angle of the user, it is possible to prevent the operation mode from being switched at a timing not intended by the user and causing stress to the user.

  In the correction device according to the present invention, the gamma curve represented by the gamma curve data approximates the luminance obtained by observing the display from below to the luminance obtained by observing the display from the front. It is preferable that the video signal is a gamma curve for correcting the video signal supplied to the display.

  According to the above configuration, the user can, for example, perform video with a brightness close to that of the video when viewing the display from the front simply by performing a predetermined operation using the input device while lying down. Can see.

  In the correction device according to the present invention, the storage unit includes (1) luminance obtained by observing the display from a first direction different from the front, and luminance obtained by observing the display from the front. First gamma curve data representing a first gamma curve for correcting the video signal supplied to the display so as to be close to (2), and (2) observing the display from a second direction different from the front. Second gamma curve data representing a second gamma curve for correcting a video signal supplied to the display is stored so that the obtained luminance approaches that obtained by observing the display from the front. And (1) the first gamma stored in the storage unit when a first user operation using the input device is performed. Switching to the first correction mode in which the video signal supplied to the display is gamma-corrected and output according to the first gamma curve, and (2) a second user operation using the input device is performed. The second gamma curve data stored in the storage unit is referred to and the video signal supplied to the display is gamma-corrected according to the second gamma curve and output to the second correction mode. It is preferable to switch.

  According to the above configuration, the gamma correction unit performs gamma correction so that the luminance represented by the video signal approaches the luminance when the display is viewed from the front, in accordance with each of the two directions in which the display is observed.

  This allows the user to perform a predetermined operation using the input device and to view the image displayed on the display from either of the two directions for observing the display when viewing the display from the front. The video can be viewed with a brightness close to that of the video.

  The correction device according to the present invention can be connected to any of a plurality of displays having different viewing angle characteristics, and the storage unit stores gamma curve data corresponding to each of the plurality of displays. The gamma correction unit preferably switches the gamma curve data to be referenced according to which of the plurality of displays is connected to the correction device.

  According to the above configuration, the gamma correction unit can perform gamma correction on the video signal using the gamma curve represented by the optimum gamma curve data for each of the plurality of displays having different viewing angle characteristics. This eliminates the need to manufacture a plurality of types of correction devices individually corresponding to the displays having different viewing angle characteristics, thereby preventing an increase in cost.

  The correction device according to the present invention can be connected to any of a plurality of displays having different panel sizes, and the storage unit stores gamma curve data corresponding to each of the plurality of displays. The gamma correction unit preferably switches the gamma curve data to be referenced according to which of the plurality of displays is connected to the correction device.

  According to the above configuration, the gamma correction can be performed on the gamma correction unit and the video signal by using the gamma curve represented by the gamma curve data optimum for each of the plurality of displays having different sizes. As a result, it is not necessary to manufacture a plurality of types of correction devices individually corresponding to the displays having different sizes, thereby preventing an increase in cost.

  The correction device according to the present invention is a color correction unit that corrects the color of a video signal supplied to the display, and when the predetermined user operation using the input device is performed, the display A color correction unit that corrects the video signal supplied to the display so that the color obtained by observing the display from a specific direction different from the front approaches the color obtained by observing the display from the front. It is preferable to provide.

  According to said structure, the said correction | amendment apparatus correct | amends both a brightness | luminance and a color to the brightness | luminance and the color obtained by observing the said display from the front according to the direction in which a user views a display. That is, on the display, an image represented by a video signal in which both brightness and color are optimized in accordance with the direction in which the user views the display is displayed.

  Therefore, for example, the user can perform a predetermined operation using the input device while lying down, and can display an image with luminance and color close to the luminance and color of the image when the display is viewed from the front. Can see.

  A television receiver including the correction device and the display is also included in the scope of the present invention.

  In the television receiver according to the present invention, it is preferable that the display displays the mode name of the correction mode in the gamma correction unit superimposed on the video represented by the video signal.

  Thus, the user can easily know in which mode the gamma correction unit 20 is operating.

  In addition, the television receiver according to the present invention further includes an OSD generation unit that generates an OSD signal to be displayed on the display, and the display is an OSD signal generated by the OSD generation unit, and the gamma correction It is preferable that the video represented by the OSD signal that has not been gamma corrected by the unit is superimposed and displayed on the video represented by the video signal that has been gamma corrected by the gamma correction unit.

  According to the above configuration, even if the user is in a state where the gamma correction unit performs gamma correction on the video signal (that is, a state not suitable for viewing from the front of the display), When the display is viewed from the front, an OSD that has not been subjected to gamma correction can be seen, so that the OSD can easily know what is displayed on the display.

  As described above, the correction device according to the present invention supplies the brightness obtained by observing the display from a specific direction different from the front to the display so as to be close to the brightness obtained by observing the display from the front. A storage unit that stores gamma curve data representing a gamma curve for correcting a video signal to be corrected, and a gamma correction unit that corrects a video signal supplied to the display, and a predetermined user operation using an input device is performed. A gamma correction unit that refers to the gamma curve data stored in the storage unit and switches to a correction mode in which the video signal supplied to the display is subjected to gamma correction according to the gamma curve and output. It is characterized by that.

  Further, as described above, the correction method of the correction apparatus according to the present invention brings the luminance obtained by observing the display from a specific direction different from the front to be close to the luminance obtained by observing the display from the front. A reading step of reading out gamma curve data representing a gamma curve for correcting the video signal supplied to the display from the storage unit, and an operation mode of the gamma correction unit for correcting the video signal supplied to the display. When the predetermined user operation used is performed, the gamma curve data read in the reading step is referred to and the video signal supplied to the display is switched to a correction mode in which gamma correction is performed according to the gamma curve and output. And a switching step.

  As a result, the user can view the image with a brightness close to the brightness of the image when viewing the display from the front only by performing a predetermined operation using the input device from a specific direction different from the front. Can do.

  Therefore, the correction device can flexibly cope with changes in viewing styles such as the installation location of the display and the wall hanging style. Further, since the display device 1 does not automatically switch the operation mode according to the viewing angle of the user, the correction device prevents the user from being stressed by switching the operation mode at a timing not intended by the user. be able to.

It is a block diagram which shows the outline | summary of a structure of the display system which concerns on one Embodiment of this invention. It is a figure which shows the outline of a structure of the remote control with which the display system which concerns on one Embodiment of this invention is provided. It is a graph which shows an example of the gamma curve which the LUT stored in the LUT memory | storage part which concerns on one Embodiment of this invention shows. It is a figure which shows an example of the image | video in which the gamma correction process was performed in the gamma correction part which concerns on one Embodiment of this invention. It is a figure which shows the relationship between the display panel of a different magnitude | size, and a user's eyes | visual_axis. It is a graph which shows an example of the relationship between the liquid crystal system of a display panel, and a viewing angle characteristic. It is a figure which shows an example of a display screen in case the display mode of the display apparatus which concerns on one Embodiment of this invention is a mode to look up. It is a graph which shows the general characteristic of the light transmittance with respect to the angle from the direction perpendicular | vertical to the front of a display. It is a figure which shows the general characteristic of the output luminance with respect to the input voltage to the pixel with which a display is equipped.

<Embodiment 1>
A correction apparatus according to an embodiment of the present invention will be described with reference to FIGS. However, unless otherwise specified, the configuration described in this embodiment is not merely intended to limit the scope of the present invention, but is merely an illustrative example.

[Display system]
First, a display system including a correction device according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing an outline of the configuration of a display system 100 according to the present embodiment.

  As shown in FIG. 1, the display system 100 includes a display device 1 and a remote controller (input device) 2.

[Configuration of display device]
Next, the display device 1 according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, the display device 1 includes a video processing unit 10, a gamma correction unit 20, an LUT storage unit (storage unit) 30, a remote control reception unit 40, and a display panel (display) 50. In the present embodiment, the gamma correction unit 20 and the LUT storage unit 30 constitute a correction device.

(Video processing part)
For example, the video processing unit 10 performs a color adjustment process on a video signal input from the outside. In addition, the video processing unit 10 performs scaling processing on the video signal.

  Here, the color adjustment processing refers to, for example, changing at least one of the sharpness and contrast of the video represented by the video signal by processing the video signal. The scaling processing refers to similar enlargement or similar reduction of the size of the video represented by the video signal by processing the video signal.

  Further, the video processing unit 10 includes a color correction unit 11 and a gamma correction unit 20 as shown in FIG. Note that the above-described color correction process may be performed in the color correction unit 11, for example.

(Gamma correction part)
The gamma correction unit 20 performs gamma correction processing on the video signal supplied from the video processing unit 10. Specifically, the gamma correction unit 20 performs the gamma curve represented by the LUT (gamma curve data: data representing the characteristics of the gamma curve) read from the LUT storage unit 30 with respect to the input gradation value of the supplied video signal. The gamma correction processing is performed with reference to FIG. Although details of the gamma correction process, the LUT, and the gamma curve will be described later, the gamma correction unit 20 performs a gamma correction process according to the angle of the line of sight of the user viewing the display panel 50 with respect to the display panel 50. Apply to signal.

(LUT storage unit)
The LUT storage unit 30 stores an LUT indicating a gamma curve referred to by the gamma correction unit 20 when the gamma correction process is performed on the video signal. The LUT storage unit 30 stores an LUT indicating a plurality of gamma curves corresponding to the angle of the user's line of sight with respect to the display panel 50.

(Remote control receiver)
The remote control receiving unit 40 acquires a remote control signal output from the remote control 2. Examples of the remote control signal include a remote control signal for switching the power of the display device 1 on and off. In addition, the remote control receiving unit 40 acquires an operation mode switching signal for switching the operation mode of the gamma correction unit 20. The operation mode switching signal will be described later.

(Display panel)
The display panel 50 displays the video represented by the video signal supplied from the gamma correction unit 20.

  In the present embodiment, the case where the display panel 50 is a liquid crystal panel will be described as an example. Of course, a plasma display panel or an EL panel may be used.

[Remote control configuration]
Next, the configuration of the remote controller 2 will be described with reference to FIG. FIG. 2 is a diagram showing an outline of the configuration of the remote controller 2 provided in the display system 100 according to the present embodiment.

  The remote controller 2 receives a user instruction for the display device 1 and outputs a remote control signal corresponding to the received user instruction to the display device 1.

  As shown in FIG. 2, the remote controller 2 includes a power button for switching the power of the display device 1 on and off, and an upper button, a lower button, a right button, and a left button for moving a cursor displayed on the display device 1. Cursor buttons and so on. In addition, the remote controller 2 includes a button 60 that looks up to accept a user instruction to switch the operation mode of the gamma correction unit 20. When the button 60 to be looked up is pressed, the remote controller 2 outputs an operation mode switching signal to the display device 1.

  In the present embodiment, the case where the input device is a remote controller will be described as an example. However, the present invention is not limited to this, and for example, a mobile phone, a smartphone, a tablet PC having a remote controller function, and the like. The input device may be realized by.

〔action mode〕
Here, an operation mode of the gamma correction unit 20 configuring the correction apparatus according to the present embodiment will be described.

  Generally, a display such as a liquid crystal panel has a viewing angle characteristic, and when a user views an image, the color of the displayed image may look different depending on the angle of the user's line of sight with respect to the display. This is also known, and the same applies to the display panel 50 according to the present embodiment. That is, the appearance of the video displayed on the display panel 50 (that is, the luminance obtained by observing the display panel 50) varies depending on the position of the user's viewpoint with respect to the display panel 50.

  When the user uses the display device 1, the video displayed on the display panel 50 is not always viewed from the front of the display panel 50 (direction perpendicular to the display surface of the display panel 50). For example, the user may lie on the floor and look up from below the front of the display surface of the display panel 50.

  At this time, as described above, the light transmittance (observation luminance) of the image when the display panel 50 is viewed (observed) from the front, and when the display panel 50 is viewed from a specific direction different from the front. The light transmittance of the image is different.

  In such a case, the gamma correction unit 20 according to the present embodiment looks at the luminance when the display panel 50 is viewed from a specific direction different from the front (the appearance of the image) when the display panel 50 is viewed from the front. It has an operation mode that approaches the brightness of the time.

  The gamma correction unit 20 operates as an “operating mode” in which the video signal is not subjected to gamma correction processing, “normal mode”, and when the user looks up from below the position perpendicular to the display surface of the display panel 50. It has a “look-up mode (correction mode)” in which gamma correction processing is performed on the video signal.

  The gamma correction unit 20 is further configured as a “first looking up mode (first correction) when the angle θ between the direction perpendicular to the display surface of the display panel 50 and the user's line of sight is 20 °. Mode) ”and“ second looking up mode (second correction mode) ”when the angle θ is 30 °.

  In the present embodiment, the case where the first and second looking-up modes are included as examples of the looking-up mode will be described as an example, but the present invention is not limited to this. For example, the looking-up mode may further include a looking-up mode when the angle θ is 10 ° and a looking-up mode when the angle is 15 °.

(Switch display mode)
In the present embodiment, the user switches between the normal mode and the look-up mode by pressing a look-up button 60 provided on the remote controller 2. Hereinafter, when the gamma correction unit 20 operates in the normal mode, it is also described that the display device 1 simply displays an image in the normal mode. It is also described that when the gamma correction unit 20 operates in the looking up mode, the display device 1 simply displays an image in the looking up mode.

  Specifically, when the display device 1 displays an image in the normal mode, for example, when the button 60 of the remote controller 2 is pressed (first user operation) by a user who lies on the floor, the display is performed from the remote controller 2. An operation mode switching signal is output to the device 1. When the remote control receiving unit 40 included in the display device 1 acquires the operation mode switching signal output from the remote control 2, the remote control receiving unit 40 supplies the operation mode switching signal to the gamma correction unit 20. When the operation mode switching signal is supplied, the gamma correction unit 20 switches the operation mode from the normal mode to the first looking up mode. In this way, the operation mode of the gamma correction unit 20 is switched from the normal mode to the first looking up mode.

  Similarly, when the operation mode is the first look-up mode, when the user presses down the look-up button 60 on the remote controller 2 (second user operation), the operation mode of the gamma correction unit 20 is changed to the first look-up mode. The mode is switched from the looking up mode to the second looking up mode. Further, when the operation mode is the second looking up mode, when the user presses the looking up button 60 on the remote controller 2, the operation mode of the gamma correction unit 20 is switched from the second looking up mode to the normal mode.

  When the operation mode of the gamma correction unit 20 is switched from the first looking up mode to the normal mode, for example, by pressing a button other than the looking up button 60 such as a “return” button provided in the remote controller 2. You may employ | adopt the structure switched to normal mode.

[LUT, gamma curve]
The above-described operation mode is realized by performing gamma correction processing on the video signal in the gamma correction unit 20 according to the gamma curve represented by the LUT stored in the LUT storage unit 30.

  Next, an example of the LUT and the gamma curve stored in the LUT storage unit 30 and referred to in the gamma correction process will be described with reference to FIG. FIG. 3 is a graph showing an example of a gamma curve indicated by the LUT stored in the LUT storage unit 30 according to the present embodiment. In the graph shown in FIG. 3, the horizontal axis represents the input gradation value of the video signal, and the vertical axis represents the output value.

  In the LUT stored in the LUT storage unit 30, output values corresponding to 256 input gradation values (0 gradation to 255 gradations) are the first looking up mode and the second looking up mode 2. It is set as street. Further, the value defined in this LUT represents the gamma curve shown in FIG.

  As shown in FIG. 3, the LUT stored in the LUT storage unit 30 is a gamma curve in which the value of the output value with respect to the input gradation value is larger than the gamma curve of the normal mode in the first look-up mode. (Curve B in FIG. 3) is represented. Furthermore, the second look-up mode represents a gamma curve (curve C in FIG. 3) in which the value of the output value with respect to the input tone value is larger than the gamma curve of the first look-up mode.

  In FIG. 3, as a reference, a curve A shows the relationship between the input gradation value and the output value in the normal mode.

  The gamma correction unit 20 according to the present embodiment performs gamma correction processing on the video signal according to the gamma curve represented by the LUT described above in each operation mode. That is, the gamma correction unit 20 performs gamma correction processing on the video signal according to the gamma curve represented by the curve B in FIG. 3 in the first looking up mode, and the gamma represented by the curve C in the second looking up mode. Gamma correction processing is performed on the video signal according to the curve.

  An example of an image that has been subjected to gamma correction processing in the display device 1 according to the present embodiment is shown in FIG. FIG. 4A shows an image when the display panel 50 is viewed from the front, and FIG. 4B is a view when the display panel is viewed from 30 ° below the front and the gamma correction processing is not performed. An image is shown, and (c) an image when the gamma correction process is performed when the display panel is viewed from 30 ° below the front.

  As shown in FIG. 4B, when the display panel 50 is viewed from below 30 degrees from the front, a dark image will be seen by the user unless the gamma correction process is performed. On the other hand, as shown in FIG. 4C, even when the display panel 50 is viewed from below 30 ° from the front, the display panel 50 is changed to a gamma correction process as shown in FIG. It is possible to present to the user an image with brightness close to that when viewed from the front.

  According to the above-described configuration, the display device 1 included in the display system 100 according to the present embodiment includes the correction device including the gamma correction unit 20 and the LUT storage unit 30, so that the user can view an image from the front of the display panel 50. Even when not viewing, it is possible to display an image close to the image when the display panel 50 is viewed from the front. That is, the gamma correction unit 20 can optimize the luminance represented by the video signal in accordance with the angle at which the user views the display panel 50.

  As a result, for example, the user can press the button 60 provided on the remote controller 2 while lying down, and can display an image with luminance close to the luminance of the image when the display panel 50 is viewed from the front. Can see.

  In addition, the display system 100 according to the present embodiment switches the operation mode of the gamma correction unit 20 only when the user operates the remote controller 2. For this reason, it can prevent that an operation mode switches at the timing which a user does not intend by the display apparatus 1 switching an operation mode automatically according to a user's viewing angle, and a user is stressed.

[Gamma correction processing optimal for display panel size]
Further, in the present embodiment, the configuration in which the position of the user's viewpoint changes is described as an example. However, even if the position of the user's viewpoint is the same, the first embodiment may be used when the display panel size is different. As in the case of, the luminance (viewing) of the displayed image may be different.

  Such a case will be described with reference to FIG. FIG. 5 is a diagram showing the relationship between display panels of different sizes and the user's line of sight.

  As shown in FIG. 5, when the display panel is small, the user's viewpoint is close to the front of the display panel, but when the display panel is large, the position of the user's viewpoint is the same. The positional relationship may be such that the user's viewpoint looks up at the display panel 50.

  However, manufacturing a plurality of types of correction devices so as to individually correspond to display panels having different panel sizes leads to an increase in cost.

  Therefore, the correction apparatus according to the present embodiment can be connected to a plurality of display panels having different sizes, and the LUT storage unit 30 may store an LUT corresponding to each of the plurality of display panels.

  The gamma correction unit 20 switches the LUT to be referenced among the LUTs stored in the LUT storage unit 30 according to whether the display panel 50 is a plurality of display panels. The gamma correction unit 20 performs gamma correction processing on the video signal using the gamma curve represented by the switched LUT.

  According to the above-described configuration, the gamma correction unit 20 according to the present embodiment performs gamma correction processing on the video signal using the gamma curve represented by the LUT optimal for each of the plurality of display panels having different sizes. be able to. In addition, since it is not necessary to manufacture a plurality of types of correction devices individually corresponding to display panels having different sizes, an increase in cost can be prevented.

  Accordingly, the display device 1 can display the video signal on which the gamma correction process optimal for the size of the display panel 50 has been performed on the display panel 50. Therefore, the user can view the video represented by the video signal that has been subjected to the gamma correction process optimal for the size of the display panel 50.

[Gamma correction processing optimal for liquid crystal systems]
In the present embodiment, the liquid crystal method (liquid crystal method) of the display panel 50 that is a liquid crystal panel is not particularly limited, but the viewing angle characteristics of the display panel 50 may differ depending on the liquid crystal method.

  However, manufacturing a plurality of types of correction devices so as to individually correspond to the display panels having different viewing angle characteristics leads to an increase in cost.

  The relationship between the liquid crystal system and viewing angle characteristics will be described with reference to FIG. FIG. 6 is a graph showing an example of the relationship between the liquid crystal system and viewing angle characteristics (source: http://pc.nikkeibp.co.jp/article/NPC/20070806/279187/). 6A shows a viewing angle characteristic when the display panel 50 is an IPS (In Plane Switching) liquid crystal system, and FIG. 6B is a viewing angle characteristic when the display panel 50 is a VA (Vertical Alignment) liquid crystal system ( c) shows viewing angle characteristics in the case of a TN (Twisted Nematic) liquid crystal system. Each of FIGS. 6A to 6C shows a boundary P having a contrast ratio of 100: 1 (maximum luminance: minimum luminance) and a boundary Q having a contrast ratio of 10: 1.

  When the display panel 50 is an IPS liquid crystal type, as shown in FIG. 6A, the contrast ratio of the front of the display panel 50 is about 400: 1 and is relatively low. Is relatively wide. Further, the viewing angle in the oblique direction is narrow.

  When the display panel 50 is a VA liquid crystal system, as shown in FIG. 6B, the contrast ratio of the front of the display panel 50 is about 500: 1, which is relatively high. Is narrower than in the IPS liquid crystal system. Further, the viewing angle in the oblique direction is narrow as in the case where the display panel 50 is of the IPS liquid crystal type.

  Further, when the display panel 50 is a TN liquid crystal system, as shown in FIG. 6C, the contrast ratio of the front of the display panel 50 is relatively high, but the vertical, left, and right viewing angles of the display panel 50 are IPS liquid crystal. It is narrower than in the case of the method and the VA liquid crystal method. On the other hand, the viewing angle in the oblique direction is wider than when the display panel 50 is an IPS liquid crystal system or a VA liquid crystal system.

  As can be seen from the boundary Q in FIGS. 6A to 6C, when the display panel 50 is the IPS liquid crystal system, the contrast ratio in the obliquely lower direction is low, and when the display panel 50 is the TN liquid crystal system, The contrast ratio is low.

  Thus, if the liquid crystal system of the display panel 50 is different, the viewing angle characteristics of the display panel 50 are different.

  Therefore, the correction device according to the present embodiment may be connected to a plurality of display devices having different viewing angle characteristics, and the LUT storage unit 30 may store an LUT corresponding to each of the plurality of display panels. .

  The gamma correction unit 20 switches the LUT to be referenced among the LUTs stored in the LUT storage unit 30 according to whether the display panel 50 is a plurality of display panels. The gamma correction unit 20 performs gamma correction processing on the video signal using the gamma curve represented by the switched LUT.

  According to the above-described configuration, the gamma correction unit 20 according to the present embodiment performs gamma correction processing on the video signal using the gamma curve represented by the LUT optimal for each of the plurality of display panels having different viewing angle characteristics. Can be applied. In addition, since it is not necessary to manufacture a plurality of types of correction devices individually corresponding to display panels having different viewing angle characteristics, an increase in cost can be prevented.

  Accordingly, the display device 1 can display on the display panel 50 a video signal that has been subjected to gamma correction processing that is optimal for the viewing angle characteristics of the display panel 50 (that is, for the liquid crystal method). Therefore, the user can view the video represented by the video signal that has been subjected to the gamma correction process optimal for the viewing angle characteristics of the display panel 50.

[Display screen]
A display screen of the display panel 50 when the operation mode of the gamma correction unit 20 is set to a look-up mode will be described with reference to FIG. FIG. 7 is a diagram illustrating an example of a display screen when the operation mode of the gamma correction unit 20 is a mode to look up. FIG. 7A shows a selection screen for selecting whether or not to always display that the mode is looking up, and FIG. 7B is a display screen after selection to always display that the mode is looking up. Is shown.

  As shown in FIG. 7 (a), the user displays a mode display indicating whether or not the mode name indicating which operation mode of the gamma correction unit 20 is set to be looked up is always displayed superimposed on the video. Settings can be selected.

  The user operation related to the mode display setting is performed by, for example, selecting home menu> setting> function switching> screen display setting in order from the top menu.

  When “Yes” is selected on the selection screen shown in FIG. 7A, a character string “set to mode 1 looking up” is superimposed on the video as shown in FIG. 7B. It will always be displayed. Note that the look-up mode 1 (mode name) shown in FIG. 7 corresponds to the first look-up mode in the present embodiment.

  Thus, since the display / non-display of the mode name of the operation mode can be selected, the user can display the operation mode when viewing the video while checking the operation mode. When it is not necessary to display the image, only the video can be displayed.

  Thus, the user can easily know in which mode the gamma correction unit 20 is operating.

  Note that the display device 1 according to the present embodiment may display a video representing the recommended viewing direction according to the operation mode together with the mode name of the operation mode of the gamma correction unit 20 on the display panel 50 while being superimposed on the video. Good. The recommended viewing direction is, for example, a direction in which the display panel 50 is looked up from below when the operation mode of the gamma correction unit 20 is looking up, and when the operation mode of the gamma correction unit 20 is in the normal mode. , Front.

  The video representing the recommended viewing direction may be, for example, an arrow indicating the recommended viewing direction or a character string such as “Recommended viewing direction is downward”.

(Optimize color)
In this embodiment, the gamma correction unit 20 has been described by taking as an example a configuration in which the gamma correction unit 20 optimizes the luminance of the video represented by the video signal according to the angle at which the user views the display panel 50 by switching the operation mode. The present invention is not limited to this.

  For example, in addition to the optimization of the luminance of the video represented by the video signal by the gamma correction unit 20, a configuration may be adopted in which the color of the video represented by the video signal by the color correction unit 11 is optimized. In this case, a correction device may be configured by the gamma correction unit 20, the LUT storage unit 30, and the color correction unit 11.

  Specifically, when the operation mode of the gamma correction unit 20 is the normal mode, the color correction unit 11 performs a normal color correction process on the video signal, and the operation mode of the gamma correction unit 20 is In the mode of looking up, a color correction process is performed on the video signal according to the angle at which the user views the display panel 50.

  In this case, the color correction unit 11 performs the first color correction process on the video signal when the operation mode of the gamma correction unit 20 is the first looking up mode, and the operation mode of the gamma correction unit 20 is In the second looking-up mode, the second color correction process may be performed on the video signal.

  Thereby, the correction device can optimize both the luminance and the color according to the angle at which the user views the display panel 50. That is, the display device 1 can display the video represented by the video signal in which both the luminance and the color are optimized according to the angle at which the user views the display panel 50 on the display panel 50.

  Therefore, for example, the user simply presses the button 60 provided on the remote controller 2 while lying down, and the brightness and color close to the brightness and color when the display panel 50 is viewed from the front. You can see the video in color.

(Remote control function)
In addition, although the case where the gamma correction unit 20 has a look-up mode in which the user performs gamma correction according to the angle at which the display panel 50 is looked up as an operation mode has been described as an example, the present invention is not limited thereto. Is not to be done. For example, it may further include a mode for performing gamma correction according to an angle that the user looks down from above the display panel 50, a mode for performing gamma correction according to an angle viewed from the side, and the like.

  Note that, when switching to the mode in which the operation mode of the gamma correction unit 20 is looked up, the configuration in which the look-up button 60 provided in the remote controller 2 is pressed has been described as an example. However, in the above case, the remote controller 2 is, for example, What is necessary is just to provide such a structure.

  For example, the remote controller 2 may include a mode switching button (not shown) for switching the operation mode of the gamma correction unit 20 instead of the button 60 to look up.

  When the mode switching button is pressed, the remote controller 2 further accepts pressing of cursor buttons (up button, down button, right button, and left button). When the right button is pressed after the mode switch button is pressed, the remote controller 2 controls the display device 1 so that the operation mode of the gamma correction unit 20 is adjusted to the angle at which the user views the display panel 50 from the right. An operation mode switching signal for switching to the mode for performing is transmitted. Further, when the left button is pressed after the mode switching button is pressed, the remote controller 2 matches the operation mode of the gamma correction unit 20 with the angle at which the user views the display panel 50 from the left with respect to the display device 1. An operation mode switching signal for switching to a mode for performing gamma correction is transmitted.

  When the right button and the lower button are pressed after the mode switch button is pressed, the remote controller 2 controls the operation mode of the gamma correction unit 20 with respect to the display device 1 from the lower right. What is necessary is just to transmit the operation mode switching signal which switches to the mode which performs the gamma correction according to the seen angle.

  As described above, the remote controller 2 may include the mode switching button, and may switch the operation mode of the gamma correction unit 20 by accepting the pressing of the cursor button after the mode switching button is pressed.

  According to the above configuration, the correction device can optimize the luminance of the video signal in accordance with various angles at which the user views the display panel 50. That is, the display device 1 can display on the display panel 50 the video represented by the video signal whose luminance is optimized in accordance with various angles at which the user views the display panel 50.

  Therefore, the user can view the image with brightness close to the brightness of the image when viewing the display panel 50 from the front, from various directions, simply by pressing the button 60 provided on the remote controller 2.

  In addition, the display device 1 according to the present embodiment performs OSD display on the display panel 50 by superimposing broadcast types such as BS broadcast and CS broadcast, channel selection, volume, external input notification information, and the like on the video. An OSD generation unit (not shown) that generates an OSD signal representing an image may be further provided.

  In this case, the display panel 50 uses the OSD signal generated by the OSD generation unit and the video represented by the OSD signal that has not been gamma corrected by the gamma correction unit 20 as the video signal that has been gamma corrected by the gamma correction unit 20. It is preferable to superimpose and display the image to be represented.

  According to the above configuration, even when the user is in a state where gamma correction is performed on the video signal in the gamma correction unit 20 (that is, a state not suitable for viewing from the front of the display panel 50), When the panel 50 is viewed from the front, an OSD that has not been subjected to gamma correction can be seen, so that the OSD can easily know what is displayed on the display panel 50.

[Program, storage medium]
Each block of the display device 1 may be realized in hardware by a logic circuit formed on an integrated circuit (IC chip), or may be realized in software using a CPU (Central Processing Unit). .

  In the latter case, the display device 1 includes a CPU that executes instructions of a program that realizes each function, a ROM (Read Only Memory) that stores the program, a RAM (Random Access Memory) that expands the program, the program, and various types of programs. A storage device (recording medium) such as a memory for storing data is provided. An object of the present invention is to provide a recording medium in which a program code (execution format program, intermediate code program, source program) of a control program of the display device 1 which is software that realizes the above-described functions is recorded in a computer-readable manner This can also be achieved by supplying the display device 1 and reading and executing the program code recorded on the recording medium by the computer (or CPU or MPU).

  Examples of the recording medium include tapes such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and disks including optical disks such as CD-ROM / MO / MD / DVD / CD-R. IC cards (including memory cards) / optical cards, semiconductor memories such as mask ROM / EPROM / EEPROM / flash ROM, PLD (Programmable logic device), FPGA (Field Programmable Gate Array), etc. Logic circuits can be used.

  The program code may be supplied to the display device 1 via a communication network. The communication network is not particularly limited as long as it can transmit the program code. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication network, and the like can be used. The transmission medium constituting the communication network may be any medium that can transmit the program code, and is not limited to a specific configuration or type. For example, even with wired lines such as IEEE1394, USB, power line carrier, cable TV line, telephone line, ADSL (Asymmetric Digital Subscriber Line) line, infrared rays such as IrDA and remote control, Bluetooth (registered trademark), IEEE80211 wireless, HDR (High Data Rate, NFC (Near Field Communication), DLNA (Digital Living Network Alliance), mobile phone network, satellite line, terrestrial digital network, etc. can also be used.

  In addition, this invention is not limited to embodiment mentioned above, A various change is possible in the range shown to the claim.

  The display device according to the present invention can be suitably applied to a television receiver, a car navigation system, and the like.

1 Display device 2 Remote control (input device)
10 video processing unit 11 color correction unit 20 gamma correction unit 30 LUT storage unit 40 remote control reception unit 50 display panel (display)
100 display system

Claims (10)

A gamma representing a gamma curve for correcting the video signal supplied to the display so that the luminance obtained by observing the display from a specific direction different from the front approaches the luminance obtained by observing the display from the front. A storage unit for storing curve data;
A gamma correction unit that corrects a video signal to be supplied to the display, and when a predetermined user operation using the input device is performed, the gamma curve data stored in the storage unit is referred to, and the display A gamma correction unit that switches to a correction mode that outputs a video signal to be supplied by performing gamma correction according to the gamma curve.
A correction device characterized by that. The gamma curve represented by the gamma curve data represents a video signal supplied to the display so that the luminance obtained by observing the display from below is close to the luminance obtained by observing the display from the front. This is a gamma curve for correction.
The correction device according to claim 1. In the storage unit, (1) the luminance obtained by observing the display from a first direction different from the front is supplied to the display so as to approach the luminance obtained by observing the display from the front. First gamma curve data representing a first gamma curve for correcting a video signal, and (2) luminance obtained by observing the display from a second direction different from the front, and the display from the front Second gamma curve data representing a second gamma curve for correcting a video signal supplied to the display so as to approximate the luminance obtained by observation is stored;
The gamma correction unit (1) refers to the first gamma curve data stored in the storage unit and is supplied to the display when a first user operation using the input device is performed. The video signal is switched to the first correction mode in which gamma correction is performed according to the first gamma curve and output. (2) When a second user operation using the input device is performed, the video signal is stored in the storage unit. The second gamma curve data is referred to, and the video signal supplied to the display is switched to a second correction mode in which gamma correction is performed according to the second gamma curve and output.
The correction apparatus according to claim 1 or 2, wherein Any of a plurality of displays having different viewing angle characteristics can be connected to the correction device,
The storage unit stores gamma curve data corresponding to each of the plurality of displays,
The gamma correction unit switches gamma curve data to be referenced according to which of the plurality of displays is a display connected to the correction device.
The correction apparatus according to any one of claims 1 to 3, wherein Any of a plurality of displays with different panel sizes can be connected to the correction device,
The storage unit stores gamma curve data corresponding to each of the plurality of displays,
The gamma correction unit switches gamma curve data to be referenced according to which of the plurality of displays is a display connected to the correction device.
The correction apparatus according to any one of claims 1 to 3, wherein A color correction unit that corrects the color of a video signal supplied to the display, and when the predetermined user operation is performed using the input device, the display is observed from a specific direction different from the front. A color correction unit that corrects a video signal supplied to the display so as to approximate the color obtained by observing the display from the front.
6. The correction apparatus according to claim 1, wherein   A television receiver comprising the correction device according to any one of claims 1 to 5 and the display. The display displays the mode name of the correction mode in the gamma correction unit superimposed on the video represented by the video signal.
The television receiver according to claim 7. An OSD generation unit that generates an OSD signal representing an image to be OSD-displayed on the display;
The display is an OSD signal generated by the OSD generation unit, and an image represented by the OSD signal not gamma corrected by the gamma correction unit is converted into a video represented by the video signal gamma corrected by the gamma correction unit. Superimposed and displayed,
The television receiver according to claim 7 or 8, wherein A gamma representing a gamma curve for correcting the video signal supplied to the display so that the luminance obtained by observing the display from a specific direction different from the front approaches the luminance obtained by observing the display from the front. A reading step of reading the curve data from the storage unit;
The operation mode of the gamma correction unit for correcting the video signal supplied to the display is referred to the gamma curve data read in the reading step when a predetermined user operation using the input device is performed, and the display Switching to a correction mode in which the video signal supplied to the gamma curve is output after being gamma corrected according to the gamma curve,
A correction method characterized by that.