Life prediction method, computer readable media including life prediction program, and life prediction device

• US 10,026,364 B2
• Filed: 01/17/2014
• Issued: 07/17/2018
• Est. Priority Date: 12/25/2013
• Status: Active Grant

• Current Assignee: Eizo Corporation
• Original Assignee: Eizo Corporation
• Inventors: Sakai, Yoshikazu
• Primary Examiner(s): MARINELLI, PATRICK
• Application Number:
  US15/107,195
• Publication Number:
  US 20170032745A1
• Time in Patent Office: 1,642 Days
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/048 using evaluation of the usage time
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

A life prediction method and device that can predict the life of a display device considering the differences between temperatures at measurements of the luminance of the display device. A monitor measures the luminance of the display screen using an optical sensor and measures the temperature around the display screen using a temperature sensor. A terminal device stores the measured luminances and temperatures in such a manner that the luminance and temperature are associated with each other. On the basis of the measured luminances and temperatures obtained by repeated measurements, the terminal device predicts the trend of changes in the luminance assuming that the temperatures at the measurements have been approximately constant, and predicts the life of the monitor on the basis of the predicted change trend.

Claims

1. A method for predicting life of a display device on the basis of a display-related characteristic value of the display device, the method comprising:

repeatedly measuring a characteristic value of the display device;

measuring a temperature of the display device at the measurement in the characteristic value;

deriving, from the measured characteristic values, an approximation straight line or an approximation curve relating to correspondence between the characteristic values and measurement times of the characteristic values;

re-deriving an approximation straight line or an approximation curve from the approximation straight line or approximation curve derived and the measured characteristic values and temperatures;

predicting, on the basis of the approximation straight line or approximation curve re-derived, a trend of changes in the characteristic values assuming that the temperatures at the measurements of the characteristic values have been a particular temperature;

calculating errors between the approximation straight line or approximation curve derived and the characteristic values measured;

calculating differences between the particular temperature and the temperatures measured;

extracting a maximum temperature difference from the differences calculated;

identifying the time when a measured temperature corresponding to the maximum temperature difference extracted has been measured;

extracting a characteristic value error with respect to a characteristic value corresponding to the measurement time identified; and

correcting the characteristic values measured on the basis of the maximum temperature difference extracted and the characteristic value error,

wherein the re-deriving includes an approximation straight line or an approximation curve on the basis of the characteristic values corrected.

2. The method for predicting the life of claim 1, wherein the re-deriving further comprises repeatedly deriving an approximation straight line or an approximation curve until the errors calculated satisfy a predetermined condition.

3. The method for predicting the life of claim 1, wherein the particular temperature is an average temperature of the temperatures measured.

4. The method for predicting the life of claim 1, further comprising:

acquiring a calibration time of the sensor; and

grouping the measured characteristic values and temperatures into a plurality of groups on the basis of the calibration time acquired, wherein

the predicting includes making a prediction for each of the groups obtained.

5. The method for predicting the life of claim 1, wherein the display device displays color images and has conversion information for color-converting an input image into an output image, the method further comprising:

acquiring the time when the conversion information has been adjusted; and

grouping the measured characteristic values and temperatures into a plurality of groups on the basis of the adjustment time acquired, wherein

the predicting includes making a prediction for each of the groups acquired.

6. The method for predicting the life of claim 4, wherein the predicting includes merging the predictions made for the groups.

7. A non-transitory computer readable media including a life prediction program for causing a computer to predict life of a display device on the basis of a display-related characteristic value of the display device, the program causing the computer to:

acquire measured values obtained by repeatedly measuring a characteristic value of the display device and measuring a temperature of the display device at the measurement of the characteristic value;

from the measured characteristic values, derive an approximation straight line or an approximation curve relating to correspondence between the characteristic values and measurement times of the characteristic values;

re-derive an approximation straight line or an approximation curve from the approximation straight line or approximation curve and the measured characteristic values and temperatures;

on the basis of the re-derived approximation straight line or approximation curve, predict a trend of changes in the characteristic values assuming that the temperatures at the measurements of the characteristic values have been a particular temperature;

calculate errors between the approximation straight line or approximation curve derived and the characteristic values measured;

calculate differences between the particular temperature and the temperatures measured;

extract a maximum temperature difference from the differences calculated;

identify the time when a measured temperature corresponding to the maximum temperature difference extracted has been measured;

extract a characteristic value error calculated with respect to a characteristic value corresponding to the measurement time identified; and

correct the characteristic values measured on the basis of the maximum temperature difference extracted and the characteristic value error extracted,

wherein re-deriving an approximation straight line or approximation curve comprises re-deriving an approximation straight line or an approximation curve on the basis of the characteristic values corrected.

8. A life prediction device for predicting life of a display device on the basis of a display-related characteristic value of the display device, the device comprising:

characteristic value acquisition means configured to acquire measured characteristic values obtained by repeatedly measuring a characteristic value of the display device;

temperature acquisition means configured to acquire measured temperatures obtained by measuring a temperature of the display device at the measurement of the characteristic value;

an approximation means configured to, from the measured characteristic values, derive an approximation straight line or an approximation curve relating to correspondence between the characteristic values and measurement times of the characteristic values;

a re-approximation means configured to re-derive an approximation straight line or an approximation curve from the approximation straight line or approximation curve derived by the approximation means and the measured characteristic values and temperatures; and

prediction means configured to, on the basis of the approximation straight line or approximation curve re-derived by the re-approximation means, predict a trend of changes in the characteristic values assuming that the temperatures at the measurements of the characteristic values have been a particular temperature;

characteristic value error calculation means of calculating errors between the approximation straight line or approximation curve derived and the characteristic values measured;

temperature difference calculation means of calculating differences between the particular temperature and the temperatures measured;

maximum temperature difference extraction means of extracting a maximum temperature difference from the differences calculated;

maximum temperature difference time identification means of identifying the time when a measured temperature corresponding to the maximum temperature difference extracted has been measured;

characteristic value error extraction means of extracting a characteristic value error calculated with respect to a characteristic value corresponding to the measurement time identified; and

correction means of correcting the characteristic values measured on the basis of the maximum temperature difference extracted and the characteristic value error extracted,

wherein the prediction means is configured to re-derive an approximation straight line or an approximation curve on the basis of the characteristic values corrected.