JP2008298834A - Liquid crystal display - Google Patents

Abstract

In a liquid crystal display device having a backlight device composed of a plurality of types of light sources, white balance can be maintained even if the luminance is reduced or extinguished due to a failure of the light sources or the like.
When a color sensor 22 detects that the brightness of an LED of a backlight device 12 composed of a fluorescent tube (CCFL) 4 and an LED 5 has decreased or turned off, the user determines whether the LED 5 is used or not used. Operates the remote controller 100 to select. When the non-use of the LED 5 is selected, the video signal supplied to the liquid crystal panel 11 by the LCD controller 6 is adjusted under the control of the main microcomputer 1 so that the white balance is maintained.
[Selection] Figure 1

Description

  The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device including a backlight device composed of a plurality of types of light sources.

Conventionally, some backlight devices used in liquid crystal display devices use a plurality of light sources such as fluorescent tubes and LEDs (Light Emitting Diodes). In such a liquid crystal display device, it is possible to select a power efficient light source according to the required luminance, thereby extending the operable duration of the battery used in the backlight device. There are some (see, for example, Patent Document 1).
Further, a white balance (WB) sensor that detects the state of the peripheral light source and a WB processing circuit that performs adjustment processing such as color balance based on a signal from the WB sensor are integrally disposed on the display unit. In addition to downsizing the device, it is possible to detect the state of ambient light (color temperature) more accurately, and adjust the color balance optimally to display images with more accurate color reproducibility. There are things that you can do.
JP 2003-114414 A Japanese Patent Laid-Open No. 11-355797

However, conventionally, in a backlight device using a plurality of light sources, when a luminance of a part of the light sources is reduced due to a failure or the like, it has not been possible for the user to make a setting not to use the light sources. Further, there has been no idea of maintaining the white balance by adjusting the signal supplied to the liquid crystal panel when the luminance of a part of the predetermined type of light source decreases or does not light up.
The present invention has been made in view of such a situation, and an object thereof is to provide a liquid crystal display device capable of solving the above-described problems.

The liquid crystal display device according to claim 1 is a liquid crystal display device that illuminates the liquid crystal panel from the back, and a fluorescent tube that irradiates light from the back to the liquid crystal panel, and light from the back to the liquid crystal panel. And a second surface opposite to the first surface of the mounting plate on which the light source is mounted on the first surface side. Measured by the chromaticity measuring means, the chromaticity measuring means for measuring the chromaticity of the light guided to the second surface side of the mounting plate by the light guiding means, and the chromaticity measuring means. Determining means for determining whether or not the LED is operating normally based on the chromaticity of the light; and control means for controlling lighting and extinguishing of the LED according to a determination result by the determining means; It is characterized by providing.
In addition, a selection unit for the user to select whether to turn on or off the LED, and when the user selects the LED to be turned off by the selection unit, the control unit controls the LED to be turned off. can do.
Further, when the LED is turned off under the control of the control means, it is possible to further include a white balance adjusting means for adjusting the white balance of the liquid crystal panel based on the measurement result by the chromaticity measuring means.
Further, the chromaticity measuring means can be arranged on the second surface side of the mounting plate on which the light source is mounted.
The control method for controlling the liquid crystal display device according to claim 5 includes a plurality of types including a fluorescent tube that emits light from a back surface to the liquid crystal panel, and an LED that emits light from the back surface to the liquid crystal panel. A light source, and a light guiding unit that guides light from the light source to a second surface side opposite to the first surface of the mounting plate on which the light source is mounted on the first surface side, A chromaticity measuring unit that measures the chromaticity of the light guided to the second surface side of the mounting plate by the light guiding unit, and a control unit that controls turning on and off of the LED, and the liquid crystal A control method for controlling a liquid crystal display device that illuminates a panel from the back, wherein the control unit is operating normally based on the chromaticity of the light measured by the chromaticity measuring unit. A determination step for determining whether or not and a determination result in the determination step Flip it, and a controlling step of controlling on and off of the LED.
In addition, the control unit performs control so that the LED is turned off in the control step when it is determined that the LED is not operating normally in the determination step and the user instructs to turn off the LED. To be able to.
Further, when the LED is turned off in the control step, a white balance adjustment step of adjusting a white balance of the liquid crystal panel based on a measurement result in the chromaticity measurement step can be further provided.
A control program for controlling a liquid crystal display device according to claim 8 includes a plurality of types of control programs including a fluorescent tube that irradiates light from the back to the liquid crystal panel and an LED that irradiates light from the back to the liquid crystal panel. A light source, and a light guiding unit that guides light from the light source to a second surface side opposite to the first surface of the mounting plate on which the light source is mounted on the first surface side, A chromaticity measuring unit that measures the chromaticity of the light guided to the second surface side of the mounting plate by the light guiding unit, and a control unit that controls turning on and off of the LED, and the liquid crystal A control program for controlling a liquid crystal display device that illuminates the panel from the back, and whether the LED operates normally based on the chromaticity of the light measured by the chromaticity measuring unit. A determination step for determining whether or not, and in the determination step, Depending on the determination result, characterized in that to execute a control step for controlling the on and off of the LED.
In addition, the control unit performs control so that the LED is turned off in the control step when it is determined that the LED is not operating normally in the determination step and the user instructs to turn off the LED. To be able to.
Further, when the LED is turned off in the control step, a white balance adjustment step of adjusting a white balance of the liquid crystal panel based on a measurement result by the chromaticity measurement unit can be further provided.

  According to the liquid crystal display device of the present invention, when at least one of a plurality of types of light sources is reduced in brightness or turned off due to a failure or the like, the types of light sources are turned off to eliminate color unevenness. Can do. Furthermore, white balance can be maintained by adjusting a signal supplied to the liquid crystal panel.

  FIG. 1 is a block diagram showing a configuration example of an embodiment of a television receiver to which the present invention is applied. As shown in the figure, in this embodiment, when a key (not shown) of the remote controller (remote controller) 100 is operated, a key operation transmitted by infrared rays or the like emitted from a light emitting unit (not shown) of the remote controller 100 is performed. Light receiving units 9 and 10 that receive corresponding commands and data, and a main microcomputer (microcomputer) 1 that controls each unit such as an LCD (Liquid Crystal Display) controller 6, a fluorescent tube (CCFL) inverter 7, and a control microcomputer 2 to be described later. Then, under the control of the main microcomputer 1, a detection signal from a color sensor 22 described later is received, and based on this detection signal, a control signal is supplied to an LED (Light Emitting Diode) driver 8 described later to drive the LED 5. A control microcomputer 2 that performs adjustment and adjusts brightness and the like, and is connected to the control microcomputer 2 and is described below. The flash memory 3 that stores various data such as reference values and the control signal from the LCD controller 6 is driven and received from a reception signal corresponding to a broadcast program of a predetermined channel received by a receiving unit (not shown) or input from an external device. A liquid crystal panel 11 for displaying an image corresponding to the received video signal, a fluorescent tube (CCFL) 4 provided on the back side of the liquid crystal panel 11 for irradiating the liquid crystal panel 11 from the back side, and the main microcomputer 1 Under the control of CCFL inverter 7 for driving and controlling fluorescent tube (CCFL) 4, red LED 5 provided on the back side of liquid crystal panel 11 for irradiating liquid crystal panel 11 with red light, and control of control microcomputer 2 Below, an LED driver 8 that drives and controls the LED 5, and a later-described chassis 2 in which the fluorescent tube 4 and the LED 5 are mounted on one surface side. (FIG. 3) is provided on the other surface side, receives light emitted from the fluorescent tube (CCFL) 4 and light emitted from the LED 5, and receives the received light as an R (red) component, G (green). ) Component and B (blue) component, and a color sensor 22 for supplying a signal corresponding to the luminance of each component to the control microcomputer 2. The liquid crystal panel 11, the fluorescent tube (CCFL) 4, the LED 5, and the color sensor 22 constitute a liquid crystal display device 13, and the fluorescent tube (CCFL) 4, the LED 5, and the color sensor 22 configure the backlight device 12. It is composed. Here, the receiving unit, the channel selection unit, and the part related to the audio output, which are essential components of the television receiver, are not directly related to the present invention, and thus illustration and description thereof are omitted.

  FIG. 2 shows a configuration example of the backlight device 12 as an illumination device in which the liquid crystal panel 11 and the optical member are removed from the liquid crystal display device 13 shown in FIG. FIG. 2A shows a plan view of the backlight device 12. FIG. 2B is a cross-sectional view taken along line AA of the backlight device 12 illustrated in FIG.

  As shown in FIG. 2, the backlight device 12 includes a fluorescent tube (CCFL) 4 and an LED 5 provided on the back surface of the liquid crystal panel 11, a color sensor 22, and the like. In this example, the LED 5 constituting the backlight device 12 is a red LED that emits only a single color light (in this case, red light) instead of emitting light of a plurality of different colors. The LED 5 functions as a light source that illuminates the liquid crystal panel 11 from the back. In order to control the LED 5, as described above, the LED driver 8 (FIG. 1) is provided.

  As a light source for illuminating the liquid crystal panel 11 from the back, not only the LED 5 but also a fluorescent tube (CCFL) 4 is provided. A CCFL inverter 7 (FIG. 1) for driving and controlling the fluorescent tube (CCFL) 4 is also provided.

  As shown in FIG. 2A, in the backlight device 12, a plurality of fluorescent tubes (CCFL) 4 are arranged in parallel so that the longitudinal direction is substantially the same direction. This is a so-called “direct-type backlight device” in which the emitted light is applied to the back surface of the liquid crystal panel 11.

  In the backlight device 12, a plurality of LEDs 5 that emit red light are disposed between adjacent fluorescent tubes (CCFL) 4 at predetermined intervals in the longitudinal direction of the fluorescent tube (CCFL) 4. Compared with the case where only the light emitted from the fluorescent tube (CCFL) 4 is irradiated on the back surface of the liquid crystal panel 11 by irradiating red light on the back surface of the liquid crystal panel 11 using the LED 5, the liquid crystal panel. This is because the color reproducibility of the video displayed on the screen 11 is widened. That is, the light emitted from the fluorescent tube (CCFL) 4 is slightly bluish, and the light emitted from the back surface of the liquid crystal panel 11 can be brought close to white light by adding the red light emitted from the LED 5. .

  FIG. 3 is a diagram illustrating a detailed configuration example of the backlight device 12. As shown in the figure, the backlight device 12 is provided on a light source mounting substrate 25 provided on the front side (side on which the liquid crystal panel 11 is disposed) of a chassis 26 described later, and on the light source mounting substrate 25. The lamp holder 92, the fluorescent tube (CCFL) 4 held by the lamp holder 92, the LED 5, the reflection plate 24, the chassis 26 to which each part is fixed, the light source mounting board 25, and the through that penetrates the chassis 26. Part of the through hole 23 that penetrates the hole 23, the light shield 27, the color sensor 22, the light source mounting substrate 25, the chassis 26, and the like is inserted from the front side and is inserted from the back side, and the locking part 32 The light guide 91 is attached by being joined to the sensor, the sensor storage chamber 34 provided on the back surface of the through hole 23, and the like.

  The light guide 91 is formed by integrally forming a plurality of holding portions 102 on the base 101 so as to hold the plurality of fluorescent tubes (CCFL) 4 at predetermined intervals. ) 4 is provided so that the chassis 26 and the light source mounting board 25 are not bent. The light guide 91 is formed of a light propagation member such as a transparent color that transmits light, transmits light emitted from the fluorescent tube (CCFL) 4 and the LED 5, and is provided on the back side of the sensor storage chamber 34. It leads to the color sensor 22 inside.

  The sensor storage chamber 34 is formed by a light blocking body 27 and a sensor substrate 33 at a position surrounding the through hole 23 on the back side of the chassis 26, and the color sensor 22 is disposed on the sensor substrate 33. By forming the sensor storage chamber 34 on the back side of the through hole 23, the light emitted from the fluorescent tube (CCFL) 4 and the LED 5 as the light source passes through the light guide 91, and the sensor storage chamber from the through hole 23. 34 is guided to the inside of the sensor 34 to irradiate the color sensor 22 and prevents light from leaking to the outside.

  In the present embodiment, in order to accurately detect a color balance shift, the light source (in this case, a plurality of fluorescent tubes (CCFL) 4 and a plurality of LEDs 5) has a predetermined size so that it can be accommodated. The reflection plate 24 and the light source mounted so that the light from the light source (in this case, the plurality of fluorescent tubes (CCFL) 4 and the plurality of LEDs 5) can pass through the formed light source mounting substrate 25 and the chassis 26. A through hole 23 penetrating the mounting substrate 25 and the chassis 26 is provided, and the color sensor 22 is disposed on the light source side (the light source mounting side of the light source mounting substrate 25 on which the light source is disposed) with the light source mounting substrate 25 and the chassis 26 interposed therebetween. (Upward side in FIG. 3)) and is disposed at a position facing the through hole 23.

  When the color sensor 22 is arranged at such a position, the light emitted from the LED 5 and directly incident on the color sensor 22 is not detected, but is propagated to some extent inside the backlight device 12, the reflector 24, the light source Since indirect light that has passed through the mounting substrate 25 and the through-hole 23 that penetrates the chassis 26 and the like can be detected, the luminance of each component of red, green, and blue light in appropriately mixed white light or It becomes possible to detect the amount of light. As described above, the color sensor 22 desirably detects light transmitted through the light propagation member such as a transparent color. In this example, in the process of propagating through the light guide 91 made of the light propagation member, a plurality of color sensors 22 are used. The seed (color, etc.) light is repeatedly reflected and mixed, and it becomes possible to detect light of each color of blue, green, and red in the mixed white light.

  Further, since the color sensor 22 is disposed on the opposite side to the light source side with the light source mounting substrate 25, the chassis 26, and the reflection plate 24 in between, the light from the light source guided to the liquid crystal panel 11 may be blocked. Absent. For this reason, it is possible to prevent the shadow of the color sensor 22 from appearing on the liquid crystal panel 11.

  It is important that the light propagation member is provided with respect to the through hole 23. For example, the light propagation member is configured to be fitted into the through hole 23 so as to close the through hole 23. be able to. For example, in the example shown in FIG. 3, a part of the light guide 91 made of a light propagation member having the protrusion 31 is inserted into the through hole 23 and fitted from above. In this case, the protrusion 31 has a function of guiding the light from the light source to the back side, and the mixed light is effectively guided to the color sensor 22. The light guide 91 made of a light propagation member is locked to the through hole 23 from the lower side by a locking portion 32 made of a light propagation member.

  By the way, the brightness of the LED 5 easily changes depending on the temperature. In particular, since the LED 5 that emits red light is greatly affected by the temperature, there may be a shift in the color of the light irradiated to the liquid crystal panel 11 due to a temperature change. In order to correct this color misregistration, as shown in FIG. 3, the color sensor 22 is disposed on the side opposite to the light source placement side of the light source mounting board 25 and passes through the light source mounting board 25 and the like. 23 is provided at a position facing 23. Thereby, the influence of the heat which arises from a light source can be suppressed.

  Further, the backlight device 12 as the illumination device according to the present embodiment includes a plurality of fluorescent tubes (CCFL) 4 as light sources, and the shape of the fluorescent tubes (CCFL) 4 is the thin shape of the liquid crystal display device 13. There is a tendency to reduce the size and length of the tube so that it can be adapted to increase in size and size. Accordingly, the fluorescent tube 4 may be bent, and the fluorescent tube 4 itself or circuit parts may be damaged due to heat generation. In addition to supporting the vicinity of both ends of the fluorescent tube 4, the fluorescent tube moves between them. A lamp holder 92 is provided.

  The lamp holder 92 may be configured to hold one fluorescent tube by one unit, but the lamp holder 92 in the present embodiment has a plurality of holding portions so as to hold the plurality of fluorescent tubes 4 at a predetermined interval. 102 is provided on the base 101 and is integrally molded.

  In addition, the light guide 91 in the present embodiment has a function of collecting the light emitted from the light source and guiding it to the color sensor 22 through the through hole 23. A plurality of holding portions 102 are provided on the base 101 so as to hold the plurality of fluorescent tubes 4 at a predetermined interval, and are integrally molded. Further, a protrusion 31 protruding from the fluorescent tube 4 is provided between the holding portions 102 so that an optical member such as a diffusion plate (not shown) is not bent. In addition to the function of preventing the optical member from bending, the light guide 91 includes the base body 101 and the holding portion 102 as described above in accordance with the shape of the lamp holder 92, holds the fluorescent tube 4, and holds the fluorescent tube. 4 also has a function of keeping the positional relationship of 4 at a predetermined interval.

  As shown in FIG. 3, the light guide 91 includes a protruding portion 31 and a locking portion 32, and in addition, a plurality of holding portions 102 (two holding portions 102 in the drawing) are integrated with the base 101. Molded. In order to fulfill the function of guiding the light emitted from the light source to the color sensor 22 side through the through hole 23, the light is formed of a transparent acrylic material or an optical fiber that can transmit light.

  The light emitted from the fluorescent tube 4 and the LED 5 as the light source is collected by the protrusion 31 of the light guide 91 and guided through the through hole 23 from the locking portion 32 to the sensor storage chamber 34. Reference numeral 34 is configured to be surrounded and sealed by the light shield 27 and the sensor substrate 33 so that the light does not leak outside from the sensor storage chamber 34.

  On the other hand, the lamp holder 92 is also attached by inserting a locking means (not shown) similar to the locking portion 32 of the light guide 91 into a through hole (not shown). In order to prevent light from the fluorescent tube 4 and the LED 5 from leaking to the outside of a cabinet (not shown) that houses the liquid crystal display device 13, it is formed of a color or material that does not transmit light.

  In the backlight device 12 configured as described above, the light emitted and mixed from the fluorescent tube 4 and the LED 5 as the light source is condensed at the protruding portion 31 of the light guide 91, and the inside of the light guide 91 , Is guided to the back side of the light source mounting substrate 25 through the through hole 23, and is detected by the color sensor 22. The color sensor 22 detects the intensity or light amount of each light component of red (R), green (G), and blue (B), and supplies a detection signal corresponding to each intensity or light amount to the control microcomputer 2.

  That is, the color sensor 22 includes a red sensor that detects red emission intensity, a green sensor that detects green emission intensity, and a blue sensor that detects blue emission intensity. The color sensor 22 includes a color filter, the red sensor detects light transmitted through a red filter that transmits light having a predetermined wavelength of red, and the green sensor transmits light having a predetermined wavelength of green. The blue sensor detects light that has passed through the green filter, and the blue sensor detects light that has passed through the blue filter that transmits blue light having a predetermined wavelength, and outputs detection signals.

  The control microcomputer 2 determines each light component (red (R), green (G), blue (B)) from the detection signal corresponding to the intensity of each light component of red, green, and blue supplied from the color sensor 22. The emission intensity of the red component corresponding to the light emitted from the LED 5 is compared with a predetermined reference value stored in advance in the flash memory 3, and each LED 5 is calculated based on the comparison result. Is fed back to adjust the emission intensity of each LED 5.

  That is, when the emission intensity of the red light emitted from the LED 5 is greater than a predetermined reference value, the control microcomputer 2 supplies a control signal that instructs the LED driver 8 to reduce the emission intensity of the LED 5. On the other hand, when the red light emission intensity emitted from the LED 5 is smaller than a predetermined reference value, a control signal for instructing the LED driver 8 to increase the light emission intensity of the LED 5 is supplied.

  FIG. 4 is a flowchart showing a procedure for switching use or non-use of the LED 5 in the backlight device 12.

  First, in step S1, the main microcomputer 1 determines whether an LED lighting signal output from the LED driver 8 is detected by the control microcomputer 2. That is, the LED driver 8 supplies a drive signal to the LED 5 and also supplies an LED lighting signal to the control microcomputer 2 when the LED 5 is driven. If it is determined that the LED detection signal is detected, the process proceeds to step S2. On the other hand, if it is determined that the LED detection signal has not been detected, the process proceeds to step S7.

  In step S2, the intensity (or the amount of light detected within a predetermined time) of the red, blue and green color components received by the color sensor 22 is measured. Next, in step S3, the chromaticity of the received light is calculated based on the measured light intensity of each color component (or the amount of light detected within a predetermined time).

  In step S4, the chromaticity of the received light calculated in step S3 and the target of feedback control of the backlight device 12 as a hybrid backlight including a plurality of types of light sources such as the fluorescent tube 4 and the LED 5 are set. A difference from the reference chromaticity is calculated, and it is determined whether or not the calculated difference is within a certain value. Here, the reference chromaticity corresponds to white.

  As a result, when it is determined that the difference is within a certain value, the process proceeds to step S5. On the other hand, if it is determined that the difference is not within a certain value, the process proceeds to step S6.

  In step S5, the main microcomputer 1 generates a user menu for designating whether to select the LED non-use mode, and displays it on the screen of the liquid crystal panel 11, for example. In this user menu, an item “LED use mode” and an item “LED non-use mode” are displayed, and any item can be selected by operating the remote controller 100 by the user. When the user operates the remote controller 100 to select “LED use mode”, the process returns to step S1, and the processes after step S1 are repeatedly executed. On the other hand, when the user operates the remote controller 100 to select “LED non-use mode”, the process proceeds to step S6.

  In step S6, under the control of the main microcomputer 1, the LED driver 8 turns off the LED 5 under the control of the control microcomputer 2. Thereafter, in step S7, the control of the main microcomputer 1 controls the darkening of green (G) and blue (B) in the display image on the liquid crystal panel 11, and the white balance is adjusted. This is because when the LED 5 is turned off, only the fluorescent tube 4 serves as a light source, and the color of the light source is bluish. Thereafter, the process ends.

  As described above, when the screen is uneven due to at least one of the LEDs 5 malfunctioning and the white balance is lost, the main microcomputer 1 automatically turns off the LED 5 when the white balance exceeds a predetermined reference range. When the white balance is lost within the predetermined reference range (within the allowable range), the user can select “LED non-use mode” to turn off the LED 5, which occurs on the screen. The uneven color can be eliminated. At that time, the user's will can be reflected. When the LED 5 is turned off, the backlight device 12 is substantially composed of only the fluorescent tube 4, but white balance is achieved by darkening the green (G) and blue (B) of the liquid crystal panel 11. Since the adjustment can be performed, the image displayed on the liquid crystal panel 11 can be prevented from being bluish and difficult to see.

  In the above embodiment, a plurality of color sensors 22 may be provided to detect a white balance shift and determine whether or not an abnormality has occurred in at least one of the LEDs 5. For example, the liquid crystal panel 11 can be divided into a plurality of rectangular blocks, and the color sensor 22 can be provided in each block. That is, the backlight device 12 shown in FIGS. 2 and 3 can be provided in each block.

  In the above embodiment, when the white balance collapses within a predetermined range, the user selects use or non-use of the LED. However, even if the white balance collapses within the predetermined range, the control of the main microcomputer 1 is performed. The control microcomputer 2 can automatically perform control to turn off all the LEDs 5 and also adjust the white balance described above.

  Further, when the liquid crystal panel 11 is virtually divided into a plurality of blocks and a plurality of backlight devices 12 are provided on the back side of the liquid crystal panel 11 corresponding to each block, the backlight device 12 of the block in which an abnormality is detected. Only the LED of the block is turned off, the brightness of the backlight device 12 of the other block is matched with the brightness of the backlight device 12 of the other block, and the white balance of the block whose LED is turned off is adjusted. It is also possible.

  The configuration and operation of the above embodiment are examples, and it goes without saying that they can be changed as appropriate without departing from the spirit of the present invention.

  The present invention can be applied not only to a television receiver but also to various display devices using a backlight.

It is a block diagram which shows the structural example of one Embodiment of the television receiver with which this invention is applied. It is a figure which shows the example of schematic structure of a backlight apparatus. It is a figure which shows the detailed structural example of a backlight apparatus. It is a flowchart which shows the procedure which switches use or non-use of LED in a backlight apparatus.

Explanation of symbols

1 Main microcomputer 2 Control microcomputer 3 Flash memory 4 Fluorescent tube (CCFL)
5 LED
6 LCD controller 7 CCFL inverter 8 LED driver 9, 10 Light receiving unit 11 Liquid crystal panel 12 Backlight device 13 Liquid crystal display device 22 Color sensor 23 Through hole 24 Reflector plate 25 Light source mounting substrate 26 Chassis 27 Light shield 31 Protrusion 32 Locking Section 33 Sensor substrate 34 Sensor storage chamber 91 Light guide 92 Lamp holder 101 Base body 102 Holding section

Claims (10)

A liquid crystal display device for illuminating a liquid crystal panel from the back,
A plurality of types of light sources including a fluorescent tube that emits light from the back to the liquid crystal panel, and an LED that emits light from the back to the liquid crystal panel;
Light guiding means for guiding light from the light source to a second surface side opposite to the first surface of the mounting plate on which the light source is mounted on the first surface side;
Chromaticity measuring means for measuring the chromaticity of the light guided to the second surface side of the mounting plate by the light guiding means;
Discrimination means for discriminating whether or not the LED is operating normally based on the chromaticity of the light measured by the chromaticity measurement means;
A liquid crystal display device comprising: control means for controlling lighting and extinguishing of the LEDs in accordance with a discrimination result by the discrimination means. A selection means for the user to select whether the LED is turned on or off;
The liquid crystal display device according to claim 1, wherein when the user selects the LED to be turned off by the selection unit, the control unit controls the LED to be turned off. The white balance adjusting means for adjusting the white balance of the liquid crystal panel based on the measurement result by the chromaticity measuring means when the LED is turned off under the control of the control means. 2. A liquid crystal display device according to 2. The liquid crystal display device according to any one of claims 1 to 3, wherein the chromaticity measuring unit is disposed on the second surface side of the mounting plate on which the light source is mounted. A plurality of types of light sources including a fluorescent tube that irradiates light from the back surface to the liquid crystal panel, and an LED that irradiates light from the back surface to the liquid crystal panel, and the light source emits light from the light source on the first surface. A light guiding portion that guides to the second surface side opposite to the first surface of the mounting plate placed on the side, and guides to the second surface side of the mounting plate by the light guiding portion A control method for controlling a liquid crystal display device that includes a chromaticity measurement unit that measures the chromaticity of the emitted light and a control unit that controls the turning on and off of the LED, and that illuminates the liquid crystal panel from the back. And
The controller is
A determination step of determining whether or not the LED is operating normally based on the chromaticity of the light measured by the chromaticity measurement unit;
And a control step for controlling lighting and extinguishing of the LED according to the discrimination result in the discrimination step. The control unit performs control so that the LED is turned off in the control step when it is determined that the LED is not operating normally in the determination step and the user instructs the LED to turn off the LED. The method of controlling a liquid crystal display device according to claim 5. The white balance adjustment step of adjusting a white balance of the liquid crystal panel based on a measurement result in the chromaticity measurement step when the LED is turned off in the control step. A control method of the liquid crystal display device according to the description. A plurality of types of light sources including a fluorescent tube that irradiates light from the back surface to the liquid crystal panel, and an LED that irradiates light from the back surface to the liquid crystal panel, and the light source emits light from the light source on the first surface. A light guiding portion that guides to the second surface side opposite to the first surface of the mounting plate placed on the side, and guides to the second surface side of the mounting plate by the light guiding portion A control program for a liquid crystal display device having a chromaticity measurement unit for measuring the chromaticity of the light and a control unit for controlling turning on and off of the LED, and illuminating the liquid crystal panel from the back,
In the control unit,
A determination step of determining whether or not the LED is operating normally based on the chromaticity of the light measured by the chromaticity measurement unit;
A control program for a liquid crystal display device, wherein a control step for controlling lighting and extinguishing of the LED is executed according to a determination result in the determination step. The control unit performs control so that the LED is turned off in the control step when it is determined that the LED is not operating normally in the determination step and the user instructs the LED to turn off the LED. A control program for a liquid crystal display device according to claim 8. The white balance adjustment step of adjusting a white balance of the liquid crystal panel based on a measurement result in the chromaticity measurement unit when the LED is turned off in the control step. A control program of the liquid crystal display device described.

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