JP6661425B2 - Image display device and control method thereof - Google Patents

Description

  The present invention relates to an image display device and a control method thereof.

  The liquid crystal display device includes a liquid crystal panel, a backlight disposed on the back side of the liquid crystal panel, a control circuit for controlling the operation thereof, and the like. In recent years, from the viewpoints of wide color gamut reproduction, power saving, and the like, liquid crystal display devices having white LEDs (LEDs emitting white light (light emitting diodes)), three primary color LEDs, and the like as backlight light emitting elements have become widespread. ing. The three primary color LEDs include a red LED, a green LED, and a blue LED.

  Here, it is said that there is a possibility that a health disorder eye may be caused by continuously viewing light (for example, blue light) on the short wavelength side in the visible wavelength range for a long time. Health disorders caused by blue light include eye fatigue, headache, changes in biological rhythm, and the like. Blue light is, for example, light having a wavelength of 380 nm or more and 495 nm or less. In the JIS standard, a function as shown in FIG. 1 is defined as an obstacle function indicating a correspondence between the wavelength of light and the degree of influence of light on a human body. The impairment function shown in FIG. 1 has a large degree (degree of influence) corresponding to the wavelength of blue light, and is therefore called a “blue light impairment function”. The spectral characteristics of a white LED or a blue LED used in a liquid crystal display device or the like have a peak wavelength near the wavelength of 450 nm (the wavelength having the highest spectral radiance). That is, the peak wavelength of the spectral characteristics of the white LED and the blue LED is close to the peak wavelength of the obstruction function (the wavelength at which the degree of influence of light on the human body is greatest). Therefore, it is said that the light emitted from the white LED or the blue LED has a particularly large effect on the human body.

  Patent Literature 1 discloses a technology that issues a warning when the accumulated time of VDT (visual display terminal such as a personal computer) work reaches a threshold value. However, in the technique disclosed in Patent Document 1, only the accumulated time of the VDT work is considered, and the colors included in the image to be displayed are not considered. Therefore, when the user of the image display apparatus views the display image containing a large amount of blue (the image displayed on the screen) for a long time, the cumulative time of the VDT work does not reach the threshold, and no warning is issued. There is. As a result, health disorders caused by light of a predetermined color such as blue light cannot be effectively prevented.

JP 2002-366129 A

  An object of the present invention is to provide a technology capable of effectively preventing a health disorder caused by light of a predetermined color.

A first aspect of the present invention provides:
Display means for displaying an image on a screen;
Based on the input image data, calculating means for calculating the amount of light of a predetermined color light emitted from the screen when an image based on the input image data is displayed on the screen,
Accumulating means for accumulating the light amount calculated by the calculating means in a display period of the image based on the input image data to calculate a total light amount of the light of the predetermined color emitted from the screen until now; ,
A notifying unit that performs a first notification when the total light amount calculated by the accumulating unit reaches a first threshold light amount ;
An image display device comprising:

A second aspect of the present invention provides:
A display step of displaying an image on a screen;
A calculating step of calculating an amount of light of a predetermined color emitted from the screen when an image based on the input image data is displayed on the screen, based on the input image data;
An accumulating step of accumulating the light amount calculated in the calculating step in a display period of the image based on the input image data to calculate a total light amount of the light of the predetermined color emitted from the screen until now; ,
A notification step of performing a first notification when the total light amount calculated in the accumulating step reaches a first threshold light amount ;
A method for controlling an image display device, comprising:

A third aspect of the present invention is a program for causing a computer to execute each step of the above-described method for controlling an image display device.

  According to the present invention, it is possible to effectively prevent health disorders caused by light of a predetermined color.

FIG. 5 is a diagram illustrating an example of a blue light impairment function according to the first embodiment. 1 is a block diagram illustrating an example of a configuration of an image display device according to a first embodiment. 5 is a flowchart illustrating an example of a processing flow of a blue light amount accumulating unit according to the first embodiment. FIG. 5 is a diagram illustrating an example of a temporal change of a blue light amount according to the first embodiment. FIG. 6 is a diagram illustrating an example of a working time and a temporal change of a total light amount according to the first embodiment. FIG. 7 is a diagram illustrating an example of a notification image according to the first embodiment. FIG. 4 is a block diagram illustrating an example of a configuration of an image display device according to a second embodiment. FIG. 7 is a diagram illustrating an example of an installation position of a photometric sensor according to a second embodiment. FIG. 9 is a block diagram illustrating an example of a configuration of an image display device according to a third embodiment. FIG. 14 is a diagram illustrating an example of a notification image according to the third embodiment. 4 is a block diagram illustrating an example of a configuration of an image display device according to a fourth embodiment. FIG. 13 is a flowchart illustrating an example of a processing flow of a mode management unit according to the fourth embodiment. FIG. 14 is a diagram illustrating an example of a notification image according to the fourth embodiment. FIG. 14 is a diagram illustrating an example of a notification image and a reduction selection image according to the fourth embodiment.

<Example 1>
Hereinafter, an image display device and a control method thereof according to the first embodiment of the present invention will be described. The present invention is applicable to any image display device. For example, the present invention can be applied to a liquid crystal display, an organic EL display, a plasma display, a projector, and the like. In this embodiment, an example in which the pixel value of the image data is an RGB value (a combination of an R value, a G value, and a B value) will be described, but the pixel value is not limited to the RGB value. For example, the pixel value may be a YCbCr value (a combination of a Y value, a Cb value, and a Cr value).

  FIG. 2 is a block diagram illustrating an example of a configuration of the image display device 1 according to the present embodiment.

  The image data input unit 11 obtains image data (input image data) input to the image display device 1 and outputs the obtained input image data to the image processing unit 12. Further, the image data input unit 11 detects input of input image data to the image display device 1 and inputs input presence / absence information indicating whether or not input image data is input to the image display device 1 to the work time accumulating unit 15. Output to The input image data is input to the image display device 1 from a personal computer, a digital camera, various recorders (hard disk recorder, Blu-ray recorder, etc.), various players, game machines, and the like. Note that the image data input unit 11 may acquire the input image data by reading the input image data from the recording medium. As a recording medium, a magnetic disk, an optical disk, a semiconductor memory, or the like can be used.

  The image processing unit 12 performs predetermined image processing on the input image data output from the image data input unit 11 to generate processed image data. The predetermined image processing is, for example, image processing for converting a pixel value of input image data according to a set color temperature, color gamut, luminance, gamma, and the like. As the predetermined image processing, edge enhancement processing, blur processing, and the like may be performed. In the predetermined image processing, for example, the pixel value of the input image data is converted using a function or a LUT (lookup table) representing the correspondence between the pixel value of the input image data and the pixel value of the processed image data. Then, the image processing unit 12 outputs the generated processed image data to the image combining unit 13.

  The image processing unit 12 uses the generated processed image data to generate an average value Rn of R values of the processed image data, an average value Gn of G values of the processed image data, and an average value of B values of the processed image data. Bn is calculated. Then, the image processing unit 12 outputs the luminance gain value L and the calculated average values Rn, Gn, Bn to the blue light amount calculation unit 18.

  Note that a value other than the average value Rn may be calculated as a representative value representing the R value of each pixel of the processed image data. For example, instead of the average value Rn, a maximum value, a minimum value, a mode value, an intermediate value, or the like of the R values of the processed image data may be calculated. The same applies to the G value and the B value.

  When the notification image data is output from the notification image generation unit 16, the image synthesis unit 13 generates the synthesis image data by synthesizing the notification image data and the processed image data output from the image processing unit 12. I do. Then, the image combining unit 13 outputs the generated combined image data to the display unit 14. The composite image data represents an image in which the notification image is superimposed on the processed image. The processed image is an image represented by the processed image data, and the notification image is an image represented by the notification image data. Details of the notification image (data) will be described later. When the notification image data is not output from the notification image generation unit 16, the image synthesis unit 13 outputs the processed image data to the display unit 14.

  The display unit 14 displays an image corresponding to the image data input to the display unit 14 on a screen. In this embodiment, an image corresponding to the processed image data or the composite image data is displayed. Further, the display unit 14 changes at least one of the color and the luminance of the screen (the image displayed on the screen) using the set parameters. In this embodiment, an example will be described in which a luminance gain value is used as the parameter. The luminance gain value is a parameter for changing the luminance of the screen. For example, if the luminance gain value is doubled, the screen luminance is also doubled, and if the luminance gain value is quadrupled, the screen luminance is also quadrupled. The above-described luminance gain value L is a current setting value of the luminance gain value.

  The method for setting the parameters is not particularly limited. For example, the parameters may be set according to a user operation, or may be automatically set according to the use environment of the image display device 1 or the like.

  The work time accumulating unit 15 measures the time during which the user work was performed (work time). The user operation is a VDT operation performed by the user using the image display device 1. In the present embodiment, the work time accumulation unit 15 measures the display time of the display target image, which is an image based on the input image data, as the work time. In this embodiment, the display target image is an image corresponding to the processed image data.

Specifically, the work time accumulating unit 15 determines whether or not input image data has been input, based on the input presence / absence information output from the image data input unit 11. The work time accumulating unit 15 regards the timing at which the input of the input image data is started (resume) as the timing at which the user work is started (resume), and the timing at which the input of the input image data is finished (interrupted). This is regarded as the timing when the user operation is terminated (interrupted). The work time accumulating unit 15 starts a first increasing process for gradually increasing the value of the work time at the timing when the input of the input image data is started. When the work time reaches the first threshold, the work time accumulation unit 15 outputs information on the work time (work time information) to the notification image generation unit 16. Then, at the timing when the input of the input image data is finished, the work time accumulating unit 15 interrupts the first increase process and starts the first reduction process of gradually reducing the value of the work time. The work time accumulating unit 15 ends the first reduction process at a timing when the value of the work time becomes 0 (zero). When the input of the input image data is started during the execution of the first reduction processing, the work time accumulating unit 15 interrupts the first reduction processing at the timing when the input of the input image data is started.

  Further, the work time accumulation unit 15 outputs work presence / absence information indicating whether or not user work is being performed to the blue light amount accumulation unit 19. The work presence information may be the same information as the input presence information, or may be information different from the input presence information.

  The unit of work time is not particularly limited. The unit of the working time may be a unit of seconds or a unit of minutes. Further, the frequency of increase or decrease of the work time is not particularly limited. For example, the work time may be updated every 1 second, may be updated every 10 seconds, or may be updated every 30 seconds. The work time may be updated every one minute, or may be updated every five minutes. Further, the amount of reduction per unit time by the first reduction processing is not particularly limited. For example, a value obtained by dividing the first threshold value by the time (rest time) required for recovery from the health disorder caused by the above work can be used as the reduction amount per unit time.

  The first reduction processing is not limited to the above processing. For example, when the display target image is not displayed until the threshold time elapses from the end of the display period of the display target image, the work time value may be reset to zero. Specifically, the work time accumulating unit 15 interrupts the first increase process at the timing when the input of the input image data is finished, and starts measuring the time during which the user work is not performed (non-work time). You may. Then, at the timing when the non-working time reaches the second threshold value (the threshold time), the working time accumulation unit 15 may reset the value of the working time to 0.

  Note that the first threshold and the second threshold described above may be values predetermined by a maker, may be values that can be changed by a user, or may be set according to the usage environment of the image display device 1. The value may be set automatically.

The storage unit 17 stores the reference luminance gain value Lb, the blue light obstruction function B (λ), and the display unit size A [m ² ]. The storage unit 17 stores a plurality of pieces of spectral data respectively corresponding to a plurality of colors including a predetermined color. In this embodiment, the predetermined color is blue. In the present embodiment, the storage unit 17 stores reference spectral data SR (λ), SG (λ), SB (λ), and SK (λ) as a plurality of spectral data. The reference luminance gain value Lb is a reference value of the luminance gain value. The reference luminance gain value Lb may be any value. The blue light impairment function B (λ) represents the correspondence between the wavelength of light and the degree of influence of light on the human body (FIG. 1). The display unit size A is the size of the screen. The reference spectral data SR (λ) is spectral data corresponding to red, the reference spectral data SG (λ) is spectral data corresponding to green, and the reference spectral data SB (λ) is spectral data corresponding to blue. Data. The reference spectral data SK (λ) is spectral data corresponding to black. The spectral data indicates the correspondence between the wavelength λ and the spectral radiance [W · m ⁻² · sr ⁻¹ · nm ⁻¹ ].

Each of the plurality of spectral data represents a spectral characteristic of light emitted from the screen when image data of a color corresponding to the spectral data is displayed on the screen. In this embodiment, each of the plurality of spectral data represents the spectral characteristics of light emitted from the screen when image data of a color corresponding to the spectral data is displayed on the screen using the reference luminance gain value Lb.

  Here, it is assumed that the gradation values (R value, G value, and B value) of the image data are 8-bit values (0 to 255). The reference spectral data SR (λ) is output from the screen when the image data of the pixel value (R value, G value, B value) = (255, 0, 0) is displayed on the screen using the reference luminance gain value Lb. Represents the spectral characteristics of the emitted light. The reference spectral data SG (λ) represents the spectral characteristics of light emitted from the screen when the image data of the pixel value (0, 255, 0) is displayed on the screen using the reference luminance gain value Lb. The reference spectral data SB (λ) represents the spectral characteristics of light emitted from the screen when the image data of the pixel value (0, 0, 255) is displayed on the screen using the reference luminance gain value Lb. The reference spectral data SK (λ) indicates the spectral characteristics of light emitted from the screen when the image data of the pixel value (0, 0, 0) is displayed on the screen using the reference luminance gain value Lb.

  Various data stored in the storage unit 17 may be updated in consideration of the aging of the display unit 14 and the like. For example, when the display unit 14 includes a light-emitting unit and a display panel that displays an image on a screen by modulating light emitted from the light-emitting unit, consideration is given to deterioration of the light-emitting unit and the liquid crystal panel over time. Thus, various data stored in the storage unit 17 may be updated. Spectral data may not be used for at least one of red, blue, green, and black. Spectral data corresponding to colors other than red, blue, green, and black may be used.

The blue light quantity calculator 18 calculates the light quantity M of blue light (blue light; light of a predetermined color) emitted from the screen when the display target image is displayed on the screen based on the input image data (processed image data). [W · sr ⁻¹ ] is calculated. Hereinafter, the light amount M is referred to as “blue light amount M”. In the present embodiment, the blue light quantity calculation unit 18 processes the image data (average values Rn, Gn, Bn), the luminance gain value L, the reference luminance gain value Lb, the blue light disturbance function B (λ), the display unit size A, The blue light amount M is calculated based on the reference spectral data SR (λ), SG (λ), SB (λ), and SK (λ). Then, the blue light quantity calculator 18 outputs the calculated blue light quantity M to the blue light quantity accumulator 19. Details of the method of calculating the blue light amount M will be described later. Blue light is, for example, light having a wavelength of 380 nm or more and 495 nm or less. Note that the wavelength range of the blue light is not limited to the wavelength range of 380 nm to 495 nm. For example, the wavelength range of blue light may be narrower or wider than the wavelength range of 380 nm to 495 nm.

  The blue light amount accumulating unit 19 calculates the total light amount MT of the blue light emitted from the screen so far by accumulating the blue light amount M calculated by the blue light amount calculating unit 18 during the display period of the display target image. In the present embodiment, the display period of the display target image is treated as the period during which the user work is performed. Therefore, the phrase "accumulate the blue light amount M during the display period of the display target image" can be replaced with the phrase "accumulate the blue light amount M during the period in which the user work is performed".

  Specifically, the blue light amount accumulating unit 19 determines whether or not a user operation is being performed based on the operation presence / absence information output from the operation time accumulating unit 15. The blue light amount accumulating unit 19 starts a second increasing process for gradually increasing the value of the total light amount MT at a timing when the user work is started (restarted). When the total light amount MT reaches the third threshold (first threshold light amount), the blue light amount accumulating unit 19 outputs information on the total light amount MT (total light amount information) to the notification image generation unit 16. Then, at the timing when the user work is completed (interrupted), the blue light amount accumulating unit 19 interrupts the second increasing process and starts a second reducing process for gradually reducing the value of the total light amount MT. The blue light amount accumulating unit 19 ends the second reduction process at the timing when the value of the total light amount MT becomes 0. When the user work is started during the execution of the second reduction processing, the blue light amount accumulating unit 19 interrupts the second reduction processing at the timing when the user work is started. Therefore, in the present embodiment, the value of the total light amount MT is gradually reduced during the non-display period of the display target image.

  The frequency of increase or decrease of the value of the total light amount MT is not particularly limited. For example, the total light amount MT may be updated every 1 second, the total light amount MT may be updated every 10 seconds, or the total light amount MT may be updated every 30 seconds. Good. The total light amount MT may be updated every one minute, or the total light amount MT may be updated every five minutes. Further, the amount of reduction per unit time by the second reduction processing is not particularly limited. For example, a value obtained by dividing the third threshold value by the time (rest time) required for recovery from a health disorder caused by blue light can be used as a reduction amount per unit time.

  The second reduction processing is not limited to the above processing. For example, the value of the total light amount MT may be reset to 0 when the display target image is not displayed until the threshold time has elapsed from the end of the display period of the display target image. Specifically, the blue light amount accumulating unit 19 may interrupt the second increasing process and start measuring the non-working time at the timing when the user's work is finished. Then, the blue light amount accumulating unit 19 may reset the value of the total light amount MT to 0 at a timing when the non-working time reaches the fourth threshold (the threshold time).

  Note that the third threshold and the fourth threshold described above may be values predetermined by the manufacturer, may be values that can be changed by the user, or may be set according to the usage environment of the image display device 1. The value may be set automatically.

  The notification image generation unit 16 performs a predetermined notification process when the work time information is output from the work time accumulation unit 15 and when the total light amount information is output from the blue light amount accumulation unit 19. In this embodiment, the notification image generation unit 16 generates notification image data when the operation time information is output from the operation time accumulation unit 15 and when the total light amount information is output from the blue light amount accumulation unit 19. Then, the generated notification image data is output to the image synthesizing unit 13. The notification image represented by the notification image data is an image that prompts interruption of the user operation. Specifically, when the work time information is output from the work time accumulation unit 15, the notification image generation unit 16 acquires information indicating the current total light amount MT from the blue light amount accumulation unit 19. Further, when the total light amount information is output from the blue light amount accumulating unit 19, the notification image generating unit 16 acquires information indicating the current working time from the working time accumulating unit 15. Then, based on the acquired information, the notification image generation unit 16 generates and outputs notification image data representing a current work time, a current total light amount MT, and a message urging the user's work to be interrupted. After that, the processing of the image synthesizing unit 13 and the display unit 14 is performed, so that the user is notified of the current work time, the current total light amount MT, and a message urging the user to stop the work.

  Note that the information to be notified to the user and the method of notification are not particularly limited as long as the user's work can be interrupted. For example, when the working time information is output from the working time accumulating unit 15, predetermined information (a message, a graphic image (mark or symbol), etc.) indicating at least that the working time has reached the first threshold is displayed on the screen. It may be displayed. When the total light amount information is output from the blue light amount accumulating unit 19, predetermined information indicating at least that the total light amount MT has reached the third threshold may be displayed on the screen. Instead of displaying an image, notification may be performed using sound or light (for example, light emitted from a lamp other than the screen).

Next, a method of calculating the amount of blue light M [W · sr ⁻¹ ] according to the present embodiment will be described.

First, the blue light amount calculation unit 18 calculates spectral data S (λ) [W · m ⁻² · sr ⁻¹ · nm ⁻¹ ] using the following equation 1. The spectral data S (λ) represents spectral characteristics of light emitted from the screen when the display target image is displayed on the screen.

Next, the blue light quantity calculation unit 18 calculates the blue light quantity M (W · sr ⁻¹ ) using the following Expression 2. In Equation 2, Δλ is a wavelength width [nm].

  Next, an example of the processing flow of the blue light amount accumulating unit 19 will be described with reference to FIG. FIG. 3 is a flowchart illustrating an example of a processing flow of the blue light amount accumulating unit 19. The blue light quantity accumulating unit 19 starts the flowchart of FIG. 3 at the timing when the image display device 1 is activated, for example. The timing for starting the flowchart in FIG. 3 is not particularly limited. For example, the flowchart of FIG. 3 may be started at a timing when a predetermined operation mode is set as the operation mode of the image display device 1. The blue light quantity accumulating unit 19 constantly (or periodically) monitors the work presence information during execution of the flowchart in FIG.

  First, the blue light amount accumulating unit 19 determines whether or not a user operation is being performed based on the operation presence / absence information from the operation time accumulating unit 15 (S101). When it is determined that the user operation is performed, the process proceeds to S102, and when it is determined that the user operation is not performed, the process returns to S101.

  In S102, the blue light amount accumulating unit 19 adds the blue light amount M output from the blue light amount calculating unit 18 to the total light amount MT. The initial value of the total light amount MT is 0. Therefore, at the start of the first user operation, the same value as the blue light amount M is set as the total light amount MT. Next, the blue light amount accumulating unit 19 determines whether or not a user operation is being performed based on the operation presence / absence information from the operation time accumulating unit 15 (S103). If it is determined that the user operation is being performed, the process proceeds to S104. If it is determined that the user operation is not performed, the process is advanced to S106.

  In S104, the blue light amount accumulating unit 19 determines whether or not the total light amount MT has reached a threshold value (third threshold value). If it is determined that the total light amount MT has reached the threshold value, the process proceeds to S105. If it is determined that the total light amount MT has not reached the threshold value, the process returns to S102. In S105, the blue light amount accumulating unit 19 outputs the total light amount MT to the notification image generating unit 16. Thereafter, the process returns to S101.

  In S106, the blue light amount accumulating unit 19 reduces the value of the total light amount MT. Next, the blue light quantity accumulating unit 19 determines whether or not a user operation is being performed based on the operation presence / absence information from the operation time accumulating unit 15 (S107). If it is determined that the user operation is not performed, the process proceeds to S108. If it is determined that the user operation is performed, the process proceeds to S102. In S108, the blue light quantity accumulating unit 19 determines whether or not the total light quantity MT has been reduced to zero. If it is determined that the total light amount MT has been reduced to 0, the process returns to S101. If it is determined that the total light amount MT has not been reduced to 0, the process returns to S106.

FIG. 4 shows an example of a time change of the blue light amount M, and FIG. 5 shows an example of a time change of a relative value of the work time value with respect to the first threshold value and a relative value of the total light amount value with respect to the third threshold value. Is shown. 4 and 5 show a time change during a period when the user work is performed. That is, FIGS. 4 and 5 show a temporal change in the display period of the display target image.

  As shown in FIG. 5, the value of the working time increases linearly with the passage of time. When the input image data is still image data, the value of the blue light amount M does not change with time. Therefore, when the input image data is image data of a still image, the value of the total light amount MT linearly increases as time elapses, similarly to the value of the work time. On the other hand, when the input image data is moving image data, the value of the blue light amount M is calculated for every N frames (N is an integer of 1 or more). For example, as the average value Rn, an average value of R values of image data of a predetermined frame in N frames or an average value of R values of image data of N frames is used. The same applies to the average values Gn and Bn. The predetermined frame is, for example, the first frame in the N frames. Then, using such average values Rn, Gn, and Bn, the blue light amount M in the period of N frames is calculated. Therefore, when the input image data is moving image data, as shown in FIG. 4, the blue light amount M changes (increases or decreases) irregularly with the passage of time. As a result, when the input image data is moving image data, as shown in FIG. 5, the total light amount MT increases irregularly with the passage of time.

  In the example of FIG. 5, the timing at which the total light amount MT reaches the third threshold is earlier than the timing at which the work time reaches the first threshold. This is because the user continued to watch an image emitting a lot of blue light. In this embodiment, in such a case, a predetermined notification (first notification) according to the fact that the total light amount MT has reached the third threshold is performed. As a result, health disorders caused by blue light can be effectively prevented.

  FIG. 6 is a diagram illustrating an example of the notification image when the timing at which the total light amount MT reaches the third threshold is earlier than the timing at which the work time reaches the first threshold. In the notification image of FIG. 6, information indicating a relative value of the work time and the total light amount MT with respect to a threshold value (prescribed value) is displayed. Specifically, in the notification image of FIG. 6, the total light amount MT has reached the third threshold value is graduated (blue light load), and the current working time is graduated (VDT work load). Further, in the notification image of FIG. 6, a message urging the user to take a rest is displayed. By displaying the notification image in FIG. 6, the user can grasp the degree of the effect of the user's work and the visual observation of the blue light on the health to date.

  As described above, according to the present embodiment, the predetermined notification is performed when the total amount of light of the predetermined color emitted from the screen to the present reaches the threshold. This makes it possible to effectively prevent health problems caused by light of a predetermined color. Further, according to the present embodiment, the predetermined notification is also performed when the time during which the user work has been performed up to the present has reached the threshold value. Thereby, health disorders caused by user work can also be effectively prevented.

  In this embodiment, an example in which the predetermined color is blue has been described, but the predetermined color is not particularly limited. For example, yellow, purple, white, and the like may be used as the predetermined color.

  Note that the notification according to the work time need not be performed. Even if the notification according to the work time is not performed, it is possible to effectively prevent health disorders caused by light of a predetermined color.

The method for calculating the blue light amount M is not particularly limited. For example, the average value of the R values of the input image data is used as the average value Rn, the average value of the G values of the input image data is used as the average value Gn, and the average value of the B values of the input image data is used as the average value Bn. May be used. This method can be suitably used when the image corresponding to the input image data is the display target image. For example, when the image display device does not include the image processing unit 12, the image processing unit 1
When the image processing by 2 is omitted, it can be suitably used. Also, “L / Lb” in Equation 1 may be omitted. The method with this change can be suitably used when the current luminance gain value is the reference luminance gain value, when a fixed value (reference luminance gain value) is used as the luminance gain value, and the like.

<Example 2>
Hereinafter, an image display device and a control method thereof according to a second embodiment of the present invention will be described. In the first embodiment, the example has been described in which the blue light amount M is calculated using the reference spectral data representing the spectral characteristics when the reference luminance gain value Lb is used. In this embodiment, an example will be described in which the blue light amount M is more accurately calculated by using current spectral data (reference spectral data) when the luminance gain value L is used. In the following, description of the same configuration and processing as in the first embodiment will be omitted.

  FIG. 7 is a block diagram illustrating an example of a configuration of the image display device 1 according to the present embodiment.

  The image processing unit 12 generates processed image data in the same manner as in the first embodiment, and outputs the generated processed image data to the image combining unit 13. Then, the image processing unit 12 calculates the average values Rn, Gn, and Bn in the same manner as in the first embodiment, and outputs the calculated average values Rn, Gn, and Bn to the blue light amount calculation unit 18. In the present embodiment, the image processing unit 12 outputs the luminance gain value L to the photometry control unit 21.

  The image combining unit 13 performs the same processing as in the first embodiment. Further, in the present embodiment, the image synthesizing unit 13 generates the photometric image data in response to the patch display request from the photometric control unit 21, and combines the processed image data with the composite image data obtained by synthesizing the processed image data. Generate. Then, the image combining unit 13 outputs the generated combined image data to the display unit 14. The composite image data obtained by combining the photometric image data with the processed image data is an image in which the photometric image is superimposed on the processed image. The photometric image is an image represented by the photometric image data. Details of the photometric image will be described later. In this embodiment, the image synthesizing unit 13 displays the processed image data when the notification image data is not output from the notification image generation unit 16 and when the patch display request is not output from the photometry control unit 21. Output to the unit 14.

The storage unit 17 stores the blue light impairment function B (λ) and the display unit size A [m ² ].

  The blue light amount calculator 18 performs the same processing as in the first embodiment. However, in this embodiment, the blue light amount calculation unit 18 calculates the processed image data (average values Rn, Gn, Bn), the blue light disturbance function B (λ), the display unit size A, and the reference spectral data SR (λ). , SG (λ), SB (λ), SK (λ), the blue light amount M is calculated. The average values Rn, Gn, Bn are obtained from the image processing unit 12, the blue light impairment function B (λ) and the display unit size A are obtained from the storage unit 17, and the reference spectral data SR (λ), SG (λ), SB (λ) and SK (λ) are obtained from the photometry control unit 21. Details of the method of calculating the blue light amount M will be described later.

  The photometric sensor 20 measures light emitted from the screen in response to a photometric request from the photometric control unit 21. Then, the photometric sensor 20 outputs a measured value (spectral data) of the light emitted from the screen to the photometric control unit 21. The photometric sensor 20 is provided, for example, at the edge of the screen. In the example of FIG. 8, it is provided at the upper right corner of the screen.

In the present embodiment, light emitted from the display area of the photometric image is measured by the photometric sensor 20 during the period in which the photometric image is displayed. The photometric image is, for example, a patch image having a uniform color, an image including a plurality of patch images respectively corresponding to a plurality of colors, a graphic image including a plurality of colors, and the like. By measuring the light emitted from the screen for each of the plurality of colors, a plurality of pieces of spectral data respectively corresponding to the plurality of colors are obtained as measured values. When one patch image is used as a photometric image, a plurality of photometric images are displayed in order, so that a plurality of spectral data respectively corresponding to a plurality of colors can be obtained. In this embodiment, the light emitted from the display area of the patch image is measured in a state where the patch image of the pixel value (255, 0, 0) is displayed using the luminance gain value L. Thereby, reference spectral data SR (λ) is obtained. The same measurement is performed for the pixel values (0, 255, 0), (0, 0, 255), (0, 0, 0), and the reference spectral data SG (λ), SB (λ), SK (λ ) Is obtained.

  In the present embodiment, the spectral data (measured value) representing the spectral characteristics when the luminance gain value L is used is not the spectral data representing the spectral characteristics when the reference luminance gain value Lb is used. SR (λ), SG (λ), SB (λ), and SK (λ). In the present embodiment, spectral data representing the current spectral characteristic is obtained as reference spectral data SR (λ), SG (λ), SB (λ), and SK (λ).

  The photometric sensor 20 may be provided movably at a position that does not overlap the screen. For example, the photometric sensor 20 may be provided so as to be housed in a bezel surrounding a screen. The position of the photometric sensor 20 may be changed manually or automatically. For example, the photometric sensor 20 may be automatically stored in the bezel during a period in which photometry (light measurement) is not performed. The photometric sensor 20 may be a separate device from the image display device 1.

  The photometry control unit 21 outputs a patch display request to the image synthesis unit 13 and outputs a photometry request to the photometry sensor 20 according to a change in the luminance gain value L output from the image processing unit 12. Then, the photometry control unit 21 acquires the measurement values (reference spectral data SR (λ), SG (λ), SB (λ), SK (λ)) output from the photometry sensor 20, and acquires the acquired measurement values. Output to the blue light quantity calculation unit 18. Therefore, in this embodiment, photometry is performed at the timing when the luminance gain value L changes. The timing of photometry is not particularly limited. For example, photometry may be performed in response to a user operation requesting photometry.

Next, a method of calculating the amount of blue light M [W · sr ⁻¹ ] according to the present embodiment will be described. First, the blue light amount calculation unit 18 calculates spectral data S (λ) [W · m ⁻² · sr ⁻¹ · nm ⁻¹ ] using the following Expression 3. Next, the blue light amount calculation unit 18 calculates the blue light amount M (W · sr ⁻¹ ) using Expression 2 described in the first embodiment.

As described above, according to the present embodiment, the blue light amount M is calculated using the reference spectral data satisfying the following conditions 1 and 2. Thereby, the blue light amount M can be calculated more accurately. As a result, health problems caused by blue light (light of a predetermined color) can be more effectively prevented.
Condition 1: The reference spectral data represents the spectral characteristics of light emitted from the screen when the image data of the color corresponding to the reference spectral data is displayed on the screen using the current setting values of the parameters.
Condition 2: The reference spectral data represents a current spectral characteristic of light emitted from the screen when image data of a color corresponding to the reference spectral data is displayed on the screen.

Note that one of the above conditions 1 and 2 may not be satisfied. If at least one of the conditions 1 and 2 is satisfied, the blue light amount M can be calculated more accurately. For example, a luminance gain value Lb may be set when a photometric image is displayed, and reference spectral data representing spectral characteristics when the luminance gain value Lb is used may be acquired. Even with such a method, reference spectral data representing the current spectral characteristics can be obtained. Specifically, reference spectral data representing the spectral characteristics of the display unit 14 in the current deteriorated state can be obtained. Further, information (a function or a table) indicating the correspondence between the luminance gain value and the reference spectral data may be prepared in advance, and the reference spectral data corresponding to the luminance gain value L may be obtained using the information.

<Example 3>
Hereinafter, an image display device and a control method thereof according to a third embodiment of the present invention will be described. In the first and second embodiments, the example in which the work time and the total light amount MT are obtained on the assumption that the number of users of the image display device is one has been described. In the present embodiment, an example in which the work time and the total light amount MT are obtained on the assumption that there are a plurality of users of the image display device will be described. In the present embodiment, for example, when a plurality of users use the simultaneous image display device, when a plurality of users use the image display device sequentially, the work time and the total light amount MT are obtained. In the following, description of the same configuration and processing as in the first embodiment will be omitted.

  FIG. 9 is a block diagram illustrating an example of a configuration of the image display device 1 according to the present embodiment.

  The imaging unit 22 generates photographed image data by photographing the front side of the screen. Then, the imaging unit 22 outputs the generated captured image data to the user identification unit 23. The imaging unit 22 is provided, for example, above the screen. The position of the imaging unit 22 is not particularly limited. The imaging unit 22 may be a device separate from the image display device 1.

  The user identification unit 23 identifies a current user of the image display device 1. In the present embodiment, the user identification unit 23 identifies the person in front of the screen as the current user of the image display device 1 by analyzing the captured image data output from the imaging unit 22. Then, the user identification unit 23 outputs information (user information) regarding the identified user to the work time accumulation unit 15. In this embodiment, image data (user image data) representing a user is used as user information. The user image data may be image data registered in advance, or may be image data extracted from captured image data. When additional information such as a user name is registered in advance, information including user image data and additional information is used as user information.

  The method for registering the user image data and the additional information is not particularly limited. For example, various data and information may be registered by a user operating the image display device 1. Various data and information may be registered using an external device such as a personal computer. Further, the method of identifying the user is not particularly limited. For example, the current user of the image display device 1 may be identified according to the user name (user ID) input to the image display device 1 by the user.

  The work time accumulating unit 15 performs the same processing as in the first embodiment. However, in the present embodiment, the work time accumulating unit 15 calculates the work time individually for each of the plurality of users. When the working time of at least one user has reached the first threshold, the working time accumulating unit 15 transmits at least the working time information and the user information of the user whose working time has reached the first threshold to a notification image. Output to the generation unit 16. When outputting the work presence / absence information to the blue light quantity accumulating section 19, the work time accumulating section 15 also outputs the user information obtained from the user identifying section 23 to the blue light quantity accumulating section 19.

  The blue light quantity accumulating unit 19 performs the same processing as in the first embodiment. However, in the present embodiment, the blue light amount accumulating unit 19 individually calculates the total light amount MT for each of the plurality of users. Then, when the total light amount MT of at least one user has reached the third threshold, the blue light amount accumulating unit 19 determines at least the total light amount information and the user information of the user whose total light amount MT has reached the third threshold value. Output to the notification image generation unit 16.

  The notification image generation unit 16 performs the same processing as in the first embodiment. However, in the present embodiment, when the work time information and the user information are output from the work time accumulation unit 15, the notification image generation unit 16 determines the current total light amount MT of the user whose work time has reached the first threshold. The indicated information is acquired from the blue light amount accumulating unit 19. When the total light amount information and the user information are output from the blue light amount accumulating unit 19, the notification image generating unit 16 outputs the information indicating the current working time of the user whose total light amount MT has reached the third threshold. Obtained from the time accumulation unit 15. Then, the notification image generation unit 16 generates and outputs notification image data based on the acquired information. Specifically, the notification image generation unit 16 obtains the user information, the current working time of the user corresponding to the obtained user information, the current total light amount MT of the user corresponding to the obtained user information, and Notification image data representing a message prompting the interruption of the notification.

  FIG. 10 is a diagram illustrating an example of a notification image according to the embodiment. FIG. 10 is a diagram illustrating an example of a notification image when the timing at which the total light amount MT reaches the third threshold is earlier than the timing at which the work time reaches the first threshold. In the notification image of FIG. 10, the work time and the total light amount MT of the user whose total light amount MT has reached the third threshold value are displayed on a scale as in the first embodiment. In the notification image of FIG. 10, as in the first embodiment, a message urging the user to take a rest is displayed. Further, in the notification image of FIG. 10, user information of the user whose total light amount MT has reached the third threshold is displayed. Thereby, the user can easily grasp who needs rest.

  The information shown in the notification image is not limited to the above information. For example, a notification image indicating various information about all users identified by the user identification unit 23 may be displayed. A notification image indicating various information about a user whose difference between the work time and the first threshold value and at least one of the difference between the total light amount MT and the third threshold value is equal to or less than the fifth threshold value may be displayed. A notification image indicating various information about the user identified by the user identification unit 23 and having the difference equal to or smaller than the fifth threshold may be displayed. The notification image may be any image as long as it can prompt the interruption of the user operation. The user information may be omitted from the notification image. A notification image in which a message such as “**** (user name) should stop the work.” May be displayed.

  As described above, according to this embodiment, the total light amount is individually calculated for each of the plurality of users of the image display device. Then, when the total light amount of at least one user has reached the threshold, a predetermined notification is made. Thereby, it is possible to suppress the predetermined notification from being performed even when the total light amount of the light of the predetermined color seen by the user is smaller than the threshold, and it is possible to notify each user at an appropriate timing. As a result, health problems of each user can be more effectively prevented. For example, in the first and second embodiments, when another user starts the user operation after the user has performed the user operation for a long time, a predetermined notification (inappropriate notification) is performed immediately after the start of the other user. There is. In the present embodiment, the occurrence of such inappropriate notification can be suppressed. Further, in the present embodiment, as the predetermined notification, a process of displaying on the screen predetermined information indicating at least the user whose total light amount has reached the threshold value is performed. This allows the user to easily know who needs rest. Note that the above processing of this embodiment can be applied to the second embodiment.

<Example 4>
Hereinafter, an image display device and a control method thereof according to a fourth embodiment of the present invention will be described. In the first, second, and third embodiments, the example in which the notification image is presented to the user when the load due to the blue light reaches the specified amount has been described. In the present embodiment, an example will be described in which, when the load due to blue light reaches a specified amount, the blue light of the image display device is reduced or the user is prompted to reduce the blue light. In the following, description of the same configuration and processing as in the first embodiment will be omitted.

  FIG. 11 is a block diagram illustrating an example of a configuration of the image display device 1 according to the present embodiment.

  The user operation receiving unit 24 receives a user operation such as pressing a button installed on the main body of the image display device 1. Then, the user operation receiving unit 24 outputs user operation information corresponding to the performed user operation to the mode management unit 25. Note that the user operation is not limited to pressing a button, and may be a user operation using an infrared remote controller, a touch panel, or the like.

  The mode management unit 25 manages the blue light reduction mode. Although the number of types of the blue light reduction mode is not particularly limited, in this embodiment, three types of blue light reduction modes, “automatic reduction”, “manual reduction”, and “no reduction” are used. The mode management unit 25 selects one of the above three modes according to the user operation information output from the user operation reception unit 24 (for example, user operation information corresponding to a user operation specifying the blue light reduction mode). And set.

  “Automatic reduction” is a mode in which the blue light (blue light amount M) is automatically reduced when the total light amount MT of blue light reaches a threshold value. In “automatic reduction”, the mode management unit 25 outputs a blue light reduction instruction for reducing the blue light amount M to the image processing unit 12 when the total light amount information is input from the blue light amount accumulation unit 19. Further, the mode management unit 25 outputs a reduction notification image generation instruction for notifying the user that the blue light amount M has been reduced to the notification image generation unit 16.

  “Manual reduction” is a mode in which the user selects whether to reduce the blue light amount M when the total blue light amount MT reaches a threshold value. In “manual reduction”, when the total light amount information is input from the blue light amount accumulating unit 19, the mode management unit 25 issues a reduction selection image generation instruction for causing the user to select whether to reduce the blue light amount M. , To the reduced selection image generation unit 26. When the user selects to reduce the blue light amount M, the mode management unit 25 outputs a blue light reduction instruction to the image processing unit 12 and outputs a reduction notification image generation instruction to the notification image generation unit 16. I do.

  “No reduction” is a mode in which the blue light amount M is not reduced even if the total blue light amount MT reaches a threshold value. In “no reduction”, the image display device 1 performs the same operation as in the first embodiment.

  When a blue light reduction instruction is input from the mode management unit 25, the image processing unit 12 further performs image processing for reducing blue (blue reduction processing) to generate processed image data. For example, as the blue reduction processing, a blue reduction filter (a coefficient by which the R value is multiplied, a coefficient by which the G value is multiplied, and a coefficient by which the B value is multiplied) = (1.0, 1.0, 0. Image processing applying 3) is performed. When the blue reduction filter (1.0, 1.0, 0.3) is used, the pixel value (R value, G value, B value) = (200, 200, 200) becomes the pixel value (200, 200, 200). 60). By such image processing, the blue light amount M can be reduced.

The order in which the predetermined image processing described in the first embodiment and the image processing for reducing blue color are performed is not particularly limited. The blue reduction process may be performed by a functional unit different from the image processing unit 12. The value of each coefficient of the blue reduction filter is not limited to the above value. The method of reducing the blue light amount M is not limited to the above method. For example, in an image display device that displays an image by modulating light from a light emitting unit (such as a backlight), the amount of blue light M can be reduced by changing the emission color of the light emitting unit. Specifically, the amount of blue light M can be reduced by reducing the blue component of the light from the light emitting unit. When the light emitting unit has a blue light source (a light source that emits blue light), the amount of blue light M can be reduced by reducing the emission luminance of the blue light source.

  When the blue light reduction mode “manual reduction” is set and the total light amount MT has reached a threshold (third threshold), the mode management unit 25 instructs the reduction selection image generation unit 26 to generate a reduction selection image. Is entered. Then, in response to the input of the reduction selection image generation instruction, the reduction selection image generation unit 26 generates the selection image data representing the reduction selection image for allowing the user to select whether or not to reduce the blue light amount M. The image data is output to the image synthesizing unit 13.

  Next, an example of a processing flow of the mode management unit 25 will be described with reference to FIG. FIG. 12 is a flowchart illustrating an example of a processing flow of the mode management unit 25. The mode management unit 25 starts the flowchart in FIG. 12 at the timing when the total light amount information is input from the blue light amount accumulation unit 19.

  First, the mode management unit 25 determines the currently set blue light reduction mode (S201). If “automatic reduction” is set, the process proceeds to S205 to execute reduction of the blue light amount M. If “manual reduction” is set, the process proceeds to S202 in order to allow the user to select whether or not to reduce the blue light amount M. If “no reduction” is set, the mode management unit 25 determines that the reduction of the blue light amount M is unnecessary, and ends the present flowchart.

  In S202, the mode management unit 25 outputs a reduction selection image generation instruction to the reduction selection image generation unit 26, and proceeds to S203. In S203, the mode management unit 25 acquires the user operation information from the user operation reception unit 24, and proceeds to S204. In S204, the mode management unit 25 determines from the user operation information whether the user has selected to reduce the blue light amount M. If the user has selected to reduce the blue light amount M, the process proceeds to S205. If the user has selected not to reduce the blue light amount M, this flowchart ends. In S205, the mode management unit 25 outputs a blue light reduction instruction to the image processing unit 12 to reduce the blue light amount M, and proceeds to S206. In S206, the mode management unit 25 outputs a reduction notification image generation instruction to the notification image generation unit 16, and ends this flowchart.

  FIG. 13 is a diagram illustrating an example of a notification image when the blue light reduction mode “automatic reduction” is set and the total light amount MT reaches a threshold (third threshold). In the notification image of FIG. 13, the work time and the total light amount MT of the user whose total light amount MT has reached the third threshold value are displayed on a scale as in the first embodiment. In the notification image of FIG. 13, as in the first embodiment, a message urging the user to take a rest is displayed. Further, in the notification image of FIG. 13, a message (reduction notification image) indicating that the amount of blue light M has been automatically reduced to reduce the load on the user is displayed. Thereby, the user can recognize that the blue light amount M has been reduced. The reduction notification image is generated by the notification image generation unit 16 in response to the reduction notification image generation instruction.

  The method of notifying the user whether or not the blue light amount M of the image display device has been reduced is not limited to the above method. For example, a blue light reduction notification mark may be displayed instead of the message. By changing the color of a power lamp or the like of the image display device body, the user may be notified whether or not the blue light amount M has been reduced. In conjunction with the audio output device, the user may be notified by a sound from the audio output device that the amount of blue light M has been reduced. The method of notifying the user of the information is not particularly limited.

FIG. 14 is a diagram illustrating an example of a notification image and a reduction selection image when the blue light reduction mode “manual reduction” is set and the total light amount MT reaches a threshold (third threshold). FIG.
In the notification image of, the work time of the user whose total light amount MT has reached the third threshold value and the total light amount MT are graduated and displayed as in the first embodiment. In the notification image of FIG. 14, as in the first embodiment, a message urging the user to take a rest is displayed. Further, in the example of FIG. 14, a menu image (reduction selection image) for allowing the user to select whether or not to reduce the blue light amount M is displayed. Thereby, the user can select whether to reduce the blue light amount M. When the user selects to reduce the amount of blue light M, a notification image similar to that in FIG. 13 is generated and displayed. The reduction selection image is generated by the reduction selection image generation unit 26 in response to the reduction selection image generation instruction, and is synthesized by the image synthesis unit 13. As a result, the reduced selection image is displayed on the screen.

  As described above, according to the present embodiment, the blue light of the image display device is automatically reduced by the blue light reduction mode “automatic reduction” when the load due to the blue light reaches the specified amount. Thereby, the load on the user for continuous work can be reduced. The blue light reduction mode “manual reduction” mode can prevent an unintended change in display color (screen color) due to automatic reduction of blue light. In addition, the blue light reduction mode can be intentionally reduced by the “manual reduction” mode. As a result, it is possible to effectively prevent the user's health disorder and also prevent the user's work from being hindered. Further, in the present embodiment, as a predetermined notification, a process of displaying information indicating that blue light has been reduced on a screen is performed. Thereby, the user can easily grasp whether the blue light of the image display device has been reduced. Note that the above processing of this embodiment is also applicable to the second and third embodiments.

  In the first to fourth embodiments, the example in which the notification image is displayed on the screen based on the total light amount MT of the blue light has been described, but is not limited thereto. The notification image may be displayed (predetermined notification) based on the blue light amount M. For example, if the amount of blue light emitted from the screen is temporarily large, there is a possibility that a health hazard may occur to the user. Therefore, when the blue light amount M calculated by the blue light amount calculation unit 18 is equal to or larger than the second threshold light amount, a second notification (display of a predetermined notification image) may be performed. For example, when the blue light amount M is equal to or greater than the second threshold light amount, an image (an image that calls attention to the user) such as “an image with a large amount of blue light. It may be a configuration. As described above, an image indicating at least that the blue light amount M is equal to or more than the second threshold light amount can be used as the notification image. The second notification may be performed when the blue light amount M is equal to or greater than the second threshold light amount, and the first notification may be performed when the total light amount MT reaches the first threshold light amount. The second threshold light amount may be a value predetermined by a manufacturer, may be a value that can be changed by a user, or may be a value that is automatically set according to a use environment of the image display device. There may be. Like the first notification, the second notification may be performed using sound, light, a graphic image, or the like.

<Other Examples>
The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or an apparatus via a network or a storage medium, and one or more processors in a computer of the system or the apparatus read and execute the program. This processing can be realized. Further, it can also be realized by a circuit (for example, an ASIC) that realizes one or more functions.

1: Image display device 13: Image synthesis unit 14: Display unit 16: Notification image generation unit 18: Blue light amount calculation unit 19: Blue light amount accumulation unit

Claims (19)

Display means for displaying an image on a screen;
Based on the input image data, calculating means for calculating the amount of light of a predetermined color light emitted from the screen when an image based on the input image data is displayed on the screen,
Accumulating means for accumulating the light amount calculated by the calculating means in a display period of the image based on the input image data to calculate a total light amount of the light of the predetermined color emitted from the screen until now; ,
A notifying unit that performs a first notification when the total light amount calculated by the accumulating unit reaches a first threshold light amount ;
An image display device comprising: The image display device according to claim 1, wherein the predetermined color is blue. The image display device according to claim 1, wherein the light of the predetermined color is light having a wavelength of 380 nm or more and 495 nm or less. A generating unit that generates processed image data by performing predetermined image processing on the input image data;
The image based on the input image data is an image according to the processed image data,
The image display device according to claim 1, wherein the calculation unit calculates the light amount based on the processed image data. The calculating means,
The input image data,
An impairment function representing the correspondence between the wavelength of light and the degree of influence of light on the human body,
The size of the screen, and
Calculating the light amount based on a plurality of pieces of spectral data respectively corresponding to a plurality of colors including the predetermined color,
5. The method according to claim 1, wherein each of the plurality of spectral data represents a spectral characteristic of light emitted from the screen when image data of a color corresponding to the spectral data is displayed on the screen. The image display device according to claim 1. The display means changes at least one of the screen color and brightness using the set parameters,
The calculation unit calculates the light amount based on the input image data, the obstacle function, the screen size, the plurality of spectral data, a current setting value of the parameter, and a reference value of the parameter. ,
Each of the plurality of spectral data represents a spectral characteristic of light emitted from the screen when image data of a color corresponding to the spectral data is displayed on the screen using a reference value of the parameter. The image display device according to claim 5, wherein The display means changes at least one of the screen color and brightness using the set parameters,
Each of the plurality of spectral data represents a spectral characteristic of light emitted from the screen when image data of a color corresponding to the spectral data is displayed on the screen using a current setting value of the parameter. The image display device according to claim 5, wherein: For each of the plurality of colors, further comprising obtaining means for obtaining spectral data representing the current spectral characteristics of light emitted from the screen when the image data of the color is displayed on the screen,
The image display device according to claim 5, wherein the calculation unit calculates the light amount using a plurality of pieces of spectral data acquired by the acquisition unit. Wherein the first notification, claim 1, wherein the total amount of light is a process for displaying at least indicating predetermined information that has reached the first threshold light intensity on the screen 1 Item 10. The image display device according to Item 1 . The image display device according to claim 1, wherein the accumulation unit gradually reduces the value of the total light amount during a non-display period of the image based on the input image data. The accumulation means, when the display of the image based on the input image data is not performed until a threshold time has elapsed from the end of the display period of the image based on the input image data, the value of the total light amount The image display device according to claim 1 , wherein the image display device is reset to zero. Further comprising identification means for identifying a current user of the image display device,
The accumulating means individually calculates the total light amount for each of a plurality of users of the image display device,
The said notification means performs the said 1st notification, when the total light amount of at least one user has reached the said 1st threshold light amount, The said 1st notification is given in any one of Claims 1-11. Image display device. The image display device according to claim 12 , wherein the first notification is a process of displaying, on the screen, predetermined information indicating at least a user whose total light amount has reached the first threshold light amount. . 14. The apparatus according to claim 1, further comprising a reduction unit configured to reduce the light amount when the total light amount calculated by the accumulation unit reaches the first threshold light amount. Image display device. The notification means, the image display apparatus according to claim 14, characterized in that the second notification if the reduction of the light amount is performed by said reducing means. When the total light amount calculated by the accumulating means has reached the first threshold light amount, further comprising a selecting means for allowing a user to select whether to reduce the light amount,
16. The image display device according to claim 14 , wherein the reducing unit reduces the light amount when the user selects to reduce the light amount. The notification means, an image display according to any one of claims 1 to 16, characterized in that the second notification if the amount of light calculated by the calculating means is a second threshold light intensity or higher apparatus. A display step of displaying an image on a screen;
A calculating step of calculating an amount of light of a predetermined color emitted from the screen when an image based on the input image data is displayed on the screen, based on the input image data;
An accumulating step of accumulating the light amount calculated in the calculating step in a display period of the image based on the input image data to calculate a total light amount of the light of the predetermined color emitted from the screen until now; ,
A notification step of performing a first notification when the total light amount calculated in the accumulating step reaches a first threshold light amount ;
A method for controlling an image display device, comprising: A program for causing a computer to execute each step of the method for controlling an image display device according to claim 18 .

Images