WO2014109091A1

WO2014109091A1 - Display device

Info

Publication number: WO2014109091A1
Application number: PCT/JP2013/073087
Authority: WO
Inventors: 政史中尾; 裕介伴場
Original assignee: Eizo株式会社
Priority date: 2013-01-10
Filing date: 2013-08-29
Publication date: 2014-07-17
Also published as: JP5426784B1; JP2014134654A

Abstract

Provided is a display device that can display with improved display characteristics without giving a user a feeling of strangeness caused by changes in display characteristics. The present invention is provided with a display characteristics correction unit (3) that corrects an input image signal (S1) to a corrected image signal (S2) that displays an image on a display panel (5) with intended display characteristics and an elapsed time calculation unit (7) that calculates elapsed time. The display characteristics correction unit (3) changes the display characteristics from first display characteristics to second display characteristics over two or more days on the basis of an output of the elapsed time calculation unit (7).

Description

Display device

The present invention relates to a display device such as a liquid crystal display device.

医 Medical monitors, especially endoscope monitors, tend to avoid changes in monitor color when a new system is introduced. This is because diagnosis by a monitor with a different color may make it difficult to grasp the state of internal organs, blood vessels, or the like, or make it difficult to distinguish between organs. Even if the display capabilities of the monitors are equivalent, different colors may occur depending on the endoscope camera or the image processing apparatus, resulting in the same problem. For this reason, the medical system vendor has corrected the preset value to the same color as that of the monitor to be replaced, in addition to measures to make the preset value the same color as that of the old product, or manually or automatically on-site.

Recent monitor emulation technology has progressed, and by adopting 3D-LUT technology in particular, it has become possible to achieve colors that are almost the same as the previous products. However, old products often have display characteristics with distortion in terms of color engineering due to specifications and deterioration over time, and there is a problem that deterioration accumulates due to repeated replacement and emulation. As a result, in the worst case, the color gamut is narrowly distorted, the gradation characteristics are not smooth, and there is a possibility that medical treatment with an endoscope system with low luminance may be forced. There is a need to solve the problem of providing better display quality while suppressing rapid changes in color due to replacement from an old product.

The present invention has been made in view of such circumstances, and provides a display device that enables display with improved display characteristics without causing the user to feel uncomfortable due to changes in display characteristics. .

According to the present invention, a display characteristic correction unit that corrects an input image signal and converts it into a corrected image signal that displays an image on a display panel with desired display characteristics, and a time lapse calculation unit that calculates a time lapse. And the display characteristic correction unit changes the display characteristic from the first display characteristic to the second display characteristic over two days or more based on the output of the time lapse calculation unit. .

The inventors of the present invention have studied to solve the above-mentioned problems, and initially considered to change display characteristics gradually over several minutes to several hours immediately after turning on the power of the display device. By adopting such a method, it is possible to improve display quality without making the user aware of changes in display characteristics during the day. However, after finishing the work of the day and taking a rest overnight, the previous image quality memorized by the user is naturally remembered, and when the improved image quality is seen the next day, it may feel uncomfortable. I understood.

Therefore, the present inventors have further studied, and over 2 days or more, if the image quality memorized by the user is gradually changed, without making the user feel uncomfortable due to the change in display characteristics, The present inventors have found that display characteristics can be improved and have completed the present invention.

The point of the present invention is that the display characteristic correcting unit changes the display characteristic for a long time of two days or more. The time required to change the image quality stored by the user without making the user feel uncomfortable varies depending on the period of use of the display device up to that point and the individual characteristics of the user, but at least two days are required. In the prior art, for the purpose of reducing power consumption, there is one that gradually changes the luminance so as not to make the user feel uncomfortable immediately after the power is turned on (for example, Japanese Patent Laid-Open No. 2005-236520). In such a technique, on the next day, immediately after the power is turned on, it is assumed that the brightness starts again in a high state, and the display characteristics are gradually changed over several days. It is completely different from thought.

Hereinafter, various embodiments of the present invention will be exemplified. The following embodiments can be combined with each other.
Preferably, the time passage calculation unit calculates the time passage based on at least one of the elapsed time and the number of event occurrences.
Preferably, the first display characteristic is a display characteristic desired by the user, and the second display characteristic is a display characteristic of a standard required for the display device or a display characteristic capable of exhibiting the performance of the display device.
Preferably, the first and second display characteristics are display characteristics before and after calibration of the display device, respectively.
Preferably, a change condition for determining a change time until the display characteristic is changed from the first display characteristic to the second display characteristic, or a change speed when the display characteristic is changed from the first display characteristic to the second display characteristic. A setting unit is further provided.
Preferably, the change condition setting unit is configured to be operable by a user.
Preferably, the change condition setting unit sets the change time based on a difference between the first display characteristic and the second display characteristic.
Preferably, the change condition setting unit sets a change speed of the display characteristic so that a color difference before and after changing the display characteristic is equal to or less than a predetermined value.
Preferably, the display characteristic correction unit changes the display characteristic when the display device is not used or when use is started.
Preferably, the display characteristic correcting unit corrects an input image signal based on a correction value and converts the image signal into a corrected image signal, and a first correction corresponding to the first display characteristic. A correction amount calculation unit that changes the value to a second correction value corresponding to the second display characteristic over two days or more.
Preferably, the display characteristic correcting unit corrects the input image signal based on a first correction value corresponding to the first display characteristic and converts the input image signal into a first image signal, and an input A second correction execution unit for correcting the image signal based on a second correction value corresponding to the second display characteristic and converting the image signal into a second image signal; and the corrected image signal from the first image signal and the second image signal. A signal synthesizing unit for synthesizing, and the signal synthesizing unit changes the corrected image signal from the first image signal to the second image signal over two days or more.
Preferably, a storage unit that stores the first and second correction values is further provided.
Preferably, the first correction value includes at least one of the first lookup table and the first matrix, and the second correction value includes at least one of the second lookup table and the second matrix.

It is a block diagram which shows the structure of the display apparatus of 1st Embodiment of this invention. An example of the transition of k in the correction value calculation formula or the image signal synthesis formula according to the usage period will be shown. A flow for realizing a method of setting a change speed of a display characteristic so that a color difference before and after changing the display characteristic becomes a predetermined value or less is shown. It is a block diagram which shows the structure of the display apparatus of 2nd Embodiment of this invention.

Hereinafter, various embodiments of the present invention will be described. Various characteristic items shown in the following embodiments can be combined with each other. Portions that are not described in the second and subsequent embodiments are the same as those in the first embodiment.

(First embodiment)
FIG. 1 is a block diagram showing the configuration of the display device 1 according to the first embodiment of the present invention. The display device 1 of the present embodiment corrects the input image signal S1 and converts it into a corrected image signal S2 for displaying an image on the display panel 5 with desired display characteristics, and a time passage. And a time-elapse calculation unit 7 for calculation.

The image signal S1 is an image signal output from a signal source such as a personal computer or an endoscope apparatus, and normally has gradation values for each of R (red), G (green), and B (blue). Consists of. The gradation value is expressed by 8 bits, for example.

The image signal S1 is converted by the display characteristic correction unit 3 to become a corrected image signal S2. The display characteristic correction unit 3 includes a correction execution unit 15 that performs correction based on the correction value set by the correction amount calculation unit 17. The correction execution unit 15 has a function of performing correction processing necessary for realizing desired display characteristics. In one example, the correction execution unit 15 includes a preceding 1D-LUT (lookup table) 23, a color conversion matrix 25, and a 3D-LUT 27. Then, a correction process using the subsequent 1D-LUT 29 is executed.

The 1D-LUT is a one-dimensional lookup table provided for each of R, G, and B. In the preceding 1D-LUT 23, the display panel (eg, liquid crystal panel) is considered to have no individual difference. The output gradation is corrected so that the gamma value becomes a desired value (for example, 2.2), and in the subsequent 1D-LUT 29, different gradation characteristics for each display panel are smoothed so as to obtain the desired gamma value. Output gradation is corrected in order to realize excellent gradation characteristics.

The color conversion matrix 25 is, for example, a 3 × 3 matrix composed of conversion coefficients corresponding to the R, G, and B components, and the color temperature and color coordinates are adjusted by correction processing using the color conversion matrix 25.

The 3D-LUT 27 is a three-dimensional lookup table that stores combinations of R, G, and B desired output gradation values for each combination of R, G, and B input gradation values. Correction processing using the LUT 27 makes it possible to reproduce colors that cannot be accurately reproduced by additive color mixing of R, G, and B, thereby improving color reproducibility.

Note that the 1D-LUT and 3D-LUT are merely examples of realizing a one-dimensional or three-dimensional gradation characteristic conversion circuit, and any circuit corresponding to a mathematical expression for realizing a desired characteristic is sufficient. Such a configuration change is adopted depending on the accuracy, circuit scale, and design period. Although these correction circuits (matrix, 1D-LUT, 3D-LUT) may be used alone, it is general that a plurality of correction circuits are required at the same time for more accurate correction as shown in FIG. .

The correction value set by the correction amount calculation unit 17 is a parameter used when the correction execution unit 15 performs correction. In the 1D-LUT or 3D-LUT, the correction value corresponds to each input gradation value in the lookup table. In the color conversion matrix, it is the value of each component of the matrix.

In the display device 1 of the present embodiment, the display characteristic correction unit 3 changes the correction value set by the correction amount calculation unit 17 from the first correction value V1 to the second correction value V2 over a period of two days or more. Thereby, the display characteristic of the display device 1 can be changed from the first display characteristic D1 to the second display characteristic D2 over two days or more. The first correction value V1 is, for example, a correction value for emulating the display characteristics of the old product, and is set to correct the display characteristics so as to match the white point and gain of the old product. The second correction value V2 is a correction value for realizing a high-quality display. Although the display characteristics of the old product are faithfully emulated at the beginning of use, the display is gradually shifted to an ideal high-quality display as the use time, the number of days, or the number of uses increases. The problem described in the background section is solved by making gradual improvements at a speed that does not allow a user such as a doctor to notice a change in display quality.

As the second display characteristics, in addition to standard ones such as sRGB, there are those that are standardly adopted in each medical institution, hospital, etc., and also in each region. Specifically, for example, in sRGB, in addition to its own color gamut, gradation characteristic γ = 2.2 and color temperature 6500K are defined. In addition, it is recommended that an X-ray medical image monitor has a gradation characteristic that is a so-called DICOM curve. Older products may deviate from these recommended characteristics due to initial specifications, aging degradation, etc., but can be converged to recommended values by such gradual improvement.

In this way, the first correction value V1 is set so that an image is displayed on the display panel 5 with the first display characteristic D1 desired by the user, and the display characteristic of the standard required for the display apparatus 1 or the performance of the display apparatus 1 is set. The second correction value V2 is set so that an image is displayed on the display panel 5 with the second display characteristic D2 including the display characteristic that can be exhibited, and the correction value set by the correction amount calculation unit 17 is changed from the first correction value V1 to the second correction value V1. By changing the correction value V2 over two days or more, it is possible to provide better display quality while suppressing a sudden change in color due to replacement from an old product.

In another application, the first correction value V1 is set so that an image is displayed on the display panel 5 with the first display characteristic D1 before calibration of the display device 1, and the second correction after calibration of the display device 1 is performed. The second correction value V2 is set so that an image is displayed on the display panel 5 with the display characteristic D2, and the correction value set by the correction amount calculation unit 17 is changed from the first correction value V1 to the second correction value V2 for two days or more. It may be changed over time. When display quality deteriorates due to changes in color temperature and luminance over time, the display device 1 can be calibrated to improve the display quality by optimizing the color temperature and luminance. Some users feel uncomfortable with changes in display characteristics before and after. However, using the display device 1 of the present embodiment, as described above, by slowly changing from the first display characteristic D1 before calibration to the second display characteristic D2 after calibration, the user feels uncomfortable. The display quality of the display device 1 can be improved.

The specific contents of the first and second correction values V1 and V2 are determined by the contents of the correction performed by the correction execution unit 15. For example, the first correction value V1 is the first lookup table and the first matrix. The second correction value V2 includes at least one of the second lookup table and the second matrix.

The first and second correction values V1 and V2 may be stored in a storage unit (not shown) provided in the display device 1 or stored in the storage unit of the signal source of the image signal S1. You may read.

The first and second correction values V1 and V2 may be fixed values determined by desired display characteristics, but are measured values from the measurement unit 9 such as an external sensor or an internal light sensor inside the monitor. The value may be corrected based on the above. As a result, the display device 1 itself is calibrated over time and changes over time, so that it is possible to provide better display quality.

The correction amount calculation unit 17 changes the correction value to be set based on the output from the time lapse calculation unit 7 that calculates the time lapse. The method by which the time lapse calculation unit 7 calculates the time lapse is not particularly limited. For example, the time lapse can be calculated based on at least one of the elapsed time and the number of event occurrences. When the display device 1 has a time measuring function, the elapsed time can be directly calculated based on the elapsed time from a certain reference time or the remaining time of a timer set at a certain reference time. On the other hand, when the display device 1 does not have a timekeeping function, it is preferable to roughly calculate the elapsed time based on the number of event occurrences. Here, the “event” is an event that occurs in the environment where the display device 1 is installed, and can be detected by the display device 1. Examples of the event include power ON / OFF of the display device, detection of the presence of a person by a human sensor, detection of darkness by an illuminance sensor, and the like. For example, if you have a custom of turning on the display device at the beginning of work during the day, turning it off before lunch break, turning it on at the beginning of the afternoon work, and turning it off before returning home, If the setting is made so that the number of times of two times or the number of times of turning off the power supply corresponds to one day, the elapsed time can be calculated by counting the number of times of turning on the power or the number of times of turning off the power. Further, if the display device 1 has a human sensor and the number of human detections by this sensor is about 10 times a day, 10 detections may be set to correspond to 1 day. In addition, when the display device 1 has an illuminance sensor, if the number of times of decrease in illuminance corresponding to darkness at night is once a day, one detection may be set to correspond to one day. . As described above, the time passage calculation unit 7 can calculate the time passage by various methods.

The method by which the correction amount calculation unit 17 changes the correction value from the first correction value V1 to the second correction value V2 is not particularly limited, and the correction value at the start of correction is the first correction value V1, from which time Any method may be used as long as it gradually approaches the second correction value V2 as time passes. As an example, the correction value set by the correction amount calculation unit 17 can be calculated by linear combination (weighted average) of the first correction value V1 and the second correction value V2 as follows. [Correction value calculation formula]
Correction value = (1−k) (V1) + k (V2) (where 0 ≦ k ≦ 1)

In the above correction value calculation formula, k is 0 at the start of use, but is a coefficient that approaches 1 as the use period and the number of days increase. FIG. 2 shows the transition of k when k is varied according to the use period and clipped to k = 1 at a certain setting time T. FIG. As shown in FIG. 2, k may be increased by a linear function, but may be a monotonous non-decreasing relationship. Further, by changing k as in the sigmoid function, the change at the start of use and the vicinity of the set time can be reduced, thereby making it difficult to experience the change. Further, k does not need to be saturated at the time of setting T, and may be a change that does not completely reach k = 1 but asymptotically approaches k = 1. The setting time T that reaches k = 1 or asymptotically requires a sufficient period of time to suppress the user's uncomfortable feeling and promote familiarity. Depending on the number of times of use, a period of several months or more may be provided. desirable. The change interval of k does not need to be as short as several seconds to several minutes, and may be every few hours to several days.

The period until the display characteristic correction unit 3 changes the display characteristic from the first display characteristic D1 to the second display characteristic D2 is, for example, 2 days to 360 days, specifically, for example, 2 days, 5 days, 10 days. Days, 30 days, 60 days, 90 days, 120 days, 240 days, 360 days, and may be any one or more of the numerical values exemplified here, or may be within a range between any two. The display property change interval is not particularly limited, and is, for example, 1 hour to 10 days. Specifically, for example, 1 hour, 3 hours, 6 hours, 12 hours, 1 day, 2 days, 5 days, It is 10 days and may be within a range between any two of the numerical values exemplified here. For example, when the change period is 10 days and the change interval is 1 day, the value of k in the correction value calculation formula is 0, 0.1, 0.2, 0.3, 0.4, 0. When the change interval is 12 hours, the value of k in the correction value calculation formula is 0, 0. .05, 0.1, 0.15... 0.9, 0.95, and 1.

Further, from another viewpoint, for example, it can be set so that the change from the first display characteristic D1 to the second display characteristic D2 is completed in a predetermined number of stages. The specified number of times is, for example, 2 to 50 times, specifically, for example, 2, 3, 5, 10, 20, 30, 40, 50, and is within the range between any two of the numerical values exemplified here. It may be. According to this setting method, for example, when the change period is 30 days and the change is completed in five stages, the display characteristics may be changed every six days.

In addition, if the display characteristics change while the user is using the display device 1, the user will easily notice the change in the display characteristics. Therefore, even when the time point at which the display characteristics are changed during use of the display device 1 is reached, the display characteristics can be changed when the display device 1 is not used or when use is started without changing the display characteristics during use. preferable. Therefore, for example, the display characteristics are changed at the timing when the power is turned on after the display device 1 is turned off, or when the presence sensor is installed, the display characteristics are changed while the absence of a person is detected. It is preferable to let them.

Change time until the display characteristic correcting unit 3 changes the display characteristic from the first display characteristic D1 to the second display characteristic D2, or a change speed when changing the display characteristic from the first display characteristic D1 to the second display characteristic D2. (Change rate per fixed time) can be set by the change condition setting unit 13. The change condition setting unit 13 can be operated by the user, and the user can set the change time and the change speed according to his / her preference. For example, when the user wants to change the display characteristics very slowly, the change time is set to a relatively long time such as 100 days, or the change speed is set to a gentle one such as 1% per day. can do.

The change condition setting unit 13 may determine the time until the change of the display characteristics is completed based on the difference between the first display characteristics D1 and the second display characteristics D2. The greater the difference between the display characteristics before and after the change, the more easily the user feels uncomfortable. Therefore, the greater the difference between the display characteristics before and after the change, the longer the time it takes to change the display characteristics. An example of the “difference” is a color difference (ΔE * ab), and the color difference (ΔE * ab) between the first display characteristic D1 and the second display characteristic D2 is calculated by a method similar to step ST2 of FIG. be able to.

Furthermore, the change condition setting unit 13 may set the change speed of the display characteristics so that the color difference before and after changing the display characteristics is equal to or less than a predetermined value. A specific example of this method will be described with reference to FIG.

First, in step ST1, the changed display characteristics are temporarily set. Specifically, the correction value is provisionally set to a value corresponding to the changed display characteristics. For example, in the above correction value calculation formula, when the correction value corresponding to the display characteristic before the change is 0.9V1 + 0.1V2 (corresponding to k = 0.1), the correction value corresponding to the display characteristic after the change is For example, 0.8V1 + 0.2V2 (corresponding to k = 0.2).

Next, in step ST2, the color difference (ΔE * ab) of the display characteristics before and after the change is calculated. The calculation method of ΔE * ab is as follows. (1) First, four RGBW points (that is, 8-bit input RGB values are (255, 0, 0), (0, 255, 0,), (0, 0, 255), (255, 255, 255)). Measure the tristimulus values X, Y, and Z at the display characteristics before and after the change with respect to 4 points) corresponding to). (2) Next, the tristimulus values X, Y, and Z are converted into L *, a *, and b *, and ΔE * ab is calculated for each of the four RGBW points based on the following formula, and the average is calculated. Find the value. In the following formulas, subscripts 1 and 2 indicate values obtained from the tristimulus values X, Y, and Z in the display characteristics before the change and the display characteristics after the change, respectively. ΔE * ab = {(ΔL *) 2+ (Δa *) 2+ (Δb) 2} 1 / 2ΔL * = L * 1-L * 2 Δa * = a * 1-a * 2 Δb * = b * 1-b * 2

Note that the color difference calculation method is not limited to the one shown here. For example, instead of using the average value of four RGBW points, another average value of several points may be used. The color difference at one point may be adopted.

Next, in step ST3, it is determined whether ΔE * ab is greater than or equal to a predetermined upper limit value. The value of ΔE * ab is an index that represents the magnitude of the change in display characteristics. If this value exceeds the upper limit, the user can easily feel discomfort with the change in display characteristics.

If ΔE * ab exceeds the upper limit (in the case of YES in step ST3), the display characteristics after the change temporarily set in step ST1 are inappropriate (the amount of change is too large), and step In ST4, the display characteristics after the change are reset so that ΔE * ab becomes the upper limit value. Specifically, for example, first, XYZ at four points of RGBW such that ΔE * ab = upper limit value is calculated backward, RGB values that cause such XYZ are determined, and then such an XYZ is determined. A correction value is set so as to generate an RGB value. As another method, the process may return to step ST1, reset the correction value so that the amount of change in display characteristics becomes smaller, and execute step ST2 and subsequent steps. The correction value to be reset is, for example, 0.85V1 + 0.15V2 (corresponding to k = 0.15).

If ΔE * ab is less than or equal to the upper limit value (NO in step ST3), there is no problem with the changed display characteristics temporarily set in step ST1, so in step ST5, the temporarily set display characteristics are used as they are. adopt.

Next, in step ST6, application of the display characteristics after change set in step ST4 or ST5 is started.

By performing the determination by the above method, it is possible to prevent the color difference before and after changing the display characteristics from becoming too large, thereby preventing the user from feeling uncomfortable due to the change in the display characteristics.

In the above example, when the changed correction value is set to 0.8V1 + 0.2V2 (corresponding to k = 0.2), the corrected value after the change is changed to the corrected value before the change after a predetermined time. Then, the correction value after the change at step ST1 is set to 0.7V1 + 0.3V2 (equivalent to k = 0.3), for example, and step ST2 and subsequent steps are executed.

Note that the flow of FIG. 3 may be executed each time the display characteristics are changed. When the display characteristics are changed in several steps, the change amount of each stage is the same or the change amount is smaller as the later stage. In this case, it may be executed only when the display characteristics are changed first.

(Second Embodiment)
FIG. 4 is a block diagram showing the configuration of the display device 1 according to the second embodiment of the present invention. The present embodiment is common to the first embodiment in that the display characteristic of the display device 1 is changed from the first display characteristic D1 to the second display characteristic D2 over two days or more. This is different from the first embodiment.

In the present embodiment, the first correction execution unit 15a corrects the display characteristics according to the first correction value V1 and outputs the corrected image signal SA, and the second correction execution unit 15b has the display characteristics according to the second correction value V2. Correction is performed to output the corrected image signal SB, and the signal synthesis unit 31 changes the output corrected image signal S2 from the first image signal SA to the second image signal SB over two days or more. Since the first image signal SA corresponds to the first display characteristic D1 and the second image display characteristic SB corresponds to the second display characteristic D2, with such a configuration, the display characteristic of the display device 1 is changed to the first display characteristic D1. The second display characteristic D2 can be changed over 2 days.

The first and second correction execution units 15a and 15b have the same configuration as the correction execution unit 15 of the first embodiment. The first and second correction values V1 and V2 are the same as in the first embodiment, and are fixed values except that the values are corrected based on the measurement values from the measurement unit 9.

The signal synthesis unit 31 has a function similar to that of the correction amount calculation unit 17 of the first embodiment in that the output value is changed over two days or more as time passes, but the correction amount calculation unit 17 sets the correction value. In contrast to the change from the first correction value V1 to the second correction value V2, the signal synthesis unit 31 changes the corrected image signal S2 from the first image signal SA to the second image signal SB. There are some differences.

The method by which the signal combining unit 31 changes the corrected image signal S2 from the first image signal SA to the second image signal SB is not particularly limited, and the corrected image signal S2 at the start time is the first image signal SA. Any method may be used as long as it gradually approaches the second image signal SB with time. As an example, the corrected image signal S2 output from the signal combining unit 31 can be calculated by linear combination (weighted average) of the first image signal SA and the second image signal SB as follows. [Image signal composition]
Corrected image signal S2 = (1−k) (SA) + k (SB) (where 0 ≦ k ≦ 1)

The first and second image signals SA and SB are data expressed by R, G, and B gradation values, respectively. For R, the R gradation value of the first image signal SA and the R gradation value of the second image signal SB are calculated according to the above-described image signal synthesis formula, whereby the R of the corrected image signal S2 is calculated. Get the tone value. The same applies to G and B.

In the above image signal synthesis formula, the mode of change of k is the same as that described in the correction value calculation formula of the first embodiment. That is, the signal synthesizing unit 31 changes k from 0 to 1 according to the time elapsed calculated by the time elapsed calculating unit 7 and the change condition set by the change condition setting unit 13.

In the first embodiment, the flow of FIG. 3 has been described using the correction value calculated based on the above-described correction value calculation formula, but the corrected image signal S2 obtained by the image signal synthesis formula may also be used. Similar explanations are possible. For example, in step ST1, when the corrected image signal S2 corresponding to the display characteristics before the change is 0.9SA + 0.1SB (corresponding to k = 0.1), the corrected image signal corresponding to the display characteristics after the change. S2 can be, for example, 0.8 SA + 0.2 SB (corresponding to k = 0.2).

Comparing the first embodiment and the second embodiment, the second embodiment requires the signal synthesis unit 31 instead of the correction amount calculation unit 17 and further requires two correction execution units. . For this reason, the second embodiment is more disadvantageous than the first embodiment in that the scale of the circuit for realizing the display characteristic correction unit 3 is likely to be larger than that of the first embodiment. However, since the configuration of each correction execution unit of the second embodiment is the same as the existing one, the second embodiment has an advantage that it can be easily configured by using an existing LSI. In contrast, the first embodiment has an advantage that the circuit scale can be easily reduced.

Claims

A display characteristic correction unit that corrects an input image signal and converts the image signal into a corrected image signal that causes the display panel to display an image with a desired display characteristic; and a time lapse calculation unit that calculates time lapse, and the display characteristic The correction unit is a display device that changes the display characteristic from the first display characteristic to the second display characteristic over two days or more based on the output of the time lapse calculation unit.
The display device according to claim 1, wherein the time lapse calculation unit calculates time lapse based on at least one of elapsed time and event occurrence count.
The first display characteristic is a display characteristic desired by a user, and the second display characteristic is a display characteristic of a standard required for the display device or a display characteristic capable of exhibiting the performance of the display device. Item 3. The display device according to Item 2.
The display device according to claim 1, wherein the first and second display characteristics are display characteristics before and after calibration of the display device, respectively.
A change condition setting unit for determining a change time until the display characteristic is changed from the first display characteristic to the second display characteristic, or a change speed when changing the display characteristic from the first display characteristic to the second display characteristic; The display device according to any one of claims 1 to 4, further comprising:
The display device according to claim 5, wherein the change condition setting unit is configured to be operable by a user.
The display device according to claim 5, wherein the change condition setting unit sets the change time based on a difference between the first display characteristic and the second display characteristic.
The change condition setting unit according to any one of claims 5 to 7, wherein the change condition setting unit sets a change speed of the display characteristic so that a color difference before and after changing the display characteristic is equal to or less than a predetermined value. Display device.
The display device according to any one of claims 1 to 8, wherein the display characteristic correction unit changes the display characteristic when the display device is not used or when use is started.
The display characteristic correction unit corrects an input image signal based on a correction value and converts the image signal into a corrected image signal, and the correction value is changed from the first correction value corresponding to the first display characteristic to the first correction value. 10. The display device according to claim 1, further comprising a correction amount calculation unit that changes the second correction value corresponding to the two display characteristics over two days or more.
The display characteristic correction unit corrects the input image signal based on a first correction value corresponding to the first display characteristic and converts it into a first image signal; and the input image signal A second correction execution unit that corrects and converts the second image signal into a second image signal based on a second correction value corresponding to the second display characteristic; and a signal that synthesizes the corrected image signal from the first image signal and the second image signal 10. The synthesis unit according to claim 1, wherein the signal synthesis unit changes the corrected image signal from the first image signal to the second image signal over two days or more. Display device.
The display device according to claim 10, further comprising a storage unit that stores the first and second correction values.
The first correction value includes at least one of a first lookup table and a first matrix, and the second correction value includes at least one of a second lookup table and a second matrix. The display device according to any one of the above.