CN110412384A

CN110412384A - OLED display service life evaluating method

Info

Publication number: CN110412384A
Application number: CN201910728996.0A
Authority: CN
Inventors: 段瑜; 张韦晨曦; 段良飞; 王光华; 尹莉; 钱福丽; 杨启鸣; 高思博; 季华夏
Original assignee: YUNNAN NORTH OLIGHTEK OPTO-ELECTRONIC TECHNOLOGY Co Ltd
Current assignee: YUNNAN NORTH OLIGHTEK OPTO-ELECTRONIC TECHNOLOGY Co Ltd
Priority date: 2019-08-08
Filing date: 2019-08-08
Publication date: 2019-11-05
Anticipated expiration: 2039-08-08
Also published as: CN110412384B

Abstract

OLED display service life evaluating method belongs to OLED display service life evaluation and test technical field, specially a kind of OLED display service life evaluating method.Method of the invention uses SED model to calculate the t under the actual use brightness of OLED display first_1/2Mode is actually used in conjunction with OLED display after value and ambient temperature calculates its actual life.The method of the invention use process that solves the problems, such as to lose contact with reality present in the appraisal procedure in existing OLED display service life is larger, considering influences the service life in practice measures big factor, the influence of use pattern and ambient temperature proposes a set of scientific and reasonable lifetime estimation method.

Description

OLED display service life evaluating method

Technical field

The invention belongs to the OLED display service life to evaluate and test technical field, specially a kind of OLED display service life evaluation and test side Method.

Background technique

OLED is organic electroluminescent LED, is to develop a kind of faster emerging display technology in recent years, is to pass through Display is realized in organic material self-luminous, which has from main light emission, low-voltage direct-current driving, all solidstate, visual angle are wide, It is light-weight, can make a series of features such as large scale and flexible panel, simple process, and there is the potentiality of low cost, energy Enough meet requirement of the current Information technology epoch to display technology higher performance and bigger information capacity, become current scientific circles and One of the project that industrial circle is most popular.

It is the self luminous reason of organic material since OLED is shown, with the stability change of organic film, and the external world The variation of water oxygen environment, brightness decay at any time.Usually brightness decay to initial value general time is referred to as partly declined Phase t_1/2, the service life of OLED display is characterized with half-life period.

The lifetime estimation method of usual OLED display is all the method using accelerated ageing, such as Chinese patent title " one The lifetime estimation method of kind of AMOLED miniscope ", appraisal procedure disclosed in the patent No. 201110158656.2, i.e., highlighted The lower attenuation curve of test brightness at any time is spent, with brightness decay SED theoretical model, each sample is calculated and is surveyed in accelerated ageing Corresponding half-life period t in examination_1/2, then extrapolate the half-life period under using brightness, the life value as OLED display.The party Method is the service life evaluating method persistently lighted based on OLED display high brightness, although can commenting as the OLED display service life Estimate, but larger with OLED display actual use process disengaging, it can not be as the assessment of OLED display actual life.

Summary of the invention

The purpose of the present invention is to propose to a kind of OLED display service life evaluating methods of close actual use process, to reach Comprehensively, close to the life appraisal of actual use process, to meet the needs of instructing OLED display business application.

A kind of service life evaluating method of OLED display of the invention carries out life-span projection using SED model, and feature exists In the t actually used under brightness for using SED model to calculate OLED display first_1/2In conjunction with OLED display reality after value Border use pattern and ambient temperature calculate its actual life, and specific formula for calculation is as follows:

LT_video&temp=LT_video× temperature factor；

LT_videoT under the=use pattern factor × actual use brightness_1/2Value；

The use pattern factor=total pixel number amount/light emitting pixel quantity；

Temperature factor numerical value is 0~1；

LT_video&tempFor the service life under use pattern and ambient temperature, LT_videoFor the service life under use pattern.

The use pattern factor does not make its value also not because the light emitting pixel quantity under different use patterns is different Equally, light emitting pixel is more in total pixel, use pattern factor tool of the use pattern factor under 1, common use pattern Body numerical value such as the following table 1；

Table 1:

Use pattern	The use pattern factor
		Video	2
Game	2
		Observation	3

At different temperature, the life value of device can difference, especially high temperature or low temperature for the temperature factor Under, its service life has a reduction compared at normal temperature, in specific value such as the following table 2；

Table 2:

Ambient temperature	Temperature factor
		- 45~-30 DEG C	1/3
- 29~-15 DEG C	1/2
		- 14~0 DEG C	2/3
0-14℃	2/3
		15-29℃	1
30-45℃	1/2

。

OLED display is in actual use, it may be possible to which the switching of different mode and ambient temperature then needs to combine The working time ratio under working time ratio and different temperatures under different mode, specific formula for calculation are as follows:

LT_video&temp=LT_video× (the working time ratio of 1 × temperature of temperature factor 1+2 × temperature of temperature factor 2 work Make time ratio ...+temperature factor N × temperature N working time ratio)；

LT_videoT under=actual use brightness_1/2Value × (working time ratio of 1 × use pattern of the use pattern factor 1+ The working time ratio ... of 2 × use pattern of the use pattern factor 2+use pattern factor M × use pattern M working time ratio；

Wherein, temperature 1 arrives the sum of working time ratio of temperature N equal to 1；Use pattern 1 arrives the working time of use pattern M Than the sum of be equal to 1.

OLED display in actual use, have an influence of use pattern and ambient temperature, therefore be used in combination The life-span projection formula of OLED display under mode and ambient temperature usually first extrapolates the service life under use pattern, then base Life-span projection under use pattern goes out the life value under temperature model.

Method of the invention solves the use that loses contact with reality present in the appraisal procedure in existing OLED display service life The larger problem of process, considering influences the service life in practice measures big factor, and the influence of use pattern and ambient temperature proposes A set of scientific and reasonable lifetime estimation method, the evaluation and test for OLED display product provide foundation.

Specific embodiment

Embodiment 1: in conjunction with real work situation, the evaluation and test of OLED display service life is carried out using method of the invention, specifically Steps are as follows:

S1: under the driving of different current drive signal cycle Ts, to the OLED displays of 6 samples in original intensity L₀ Brightness under carry out device accelerated ageing test.Wherein, driving signal cycle T is in 500ms hereinafter, original intensity L₀At least 1000cd/m², 200cd/m is spaced between the original intensity of 6 samples is each².To 6 samples apply different electric currents be respectively I₀ ¹、I₀ ²、I₀ ³、I₀ ⁴、I₀ ⁵、I₀ ⁶, specific corresponding initial luma values are L₀ ¹、L₀ ²、L₀ ³、L₀ ⁴、L₀ ⁵、L₀ ⁶, occurrence are as follows:

S2: the theoretical model of tensile figure decaying SED, the mathematics of model are established to the brightness decay during accelerated ageing Expression formula are as follows:

L_(t)/L₀=exp [- (t/ τ)^β] (formula 1)

Wherein, t is time, L_(t)For the brightness at corresponding moment, L₀For original intensity, τ and β are two undetermined coefficients, are passed through The fitting of L-t curve finds out τ and β, then enables L_(t)/L₀=0.5, service life t can be found out_1/2；

According to this formula, different electric currents, corresponding half-life period t under different original intensities are calculated separately out_1/2, it is listed in Following table:

S3: life-span projection model, the mathematic(al) representation of prediction model are established are as follows:

L₀ ⁿ×t_1/2=C (formula 2)

Wherein L₀For original intensity, t_1/2For half-life period；

By the L of sample each in S2₀Value and corresponding t_1/2Value substitutes into formula 2, finds out n and C by fitting, into One step finds out the expression formula, then actually uses brightness according to display, finds out the t under actual use brightness_1/2Value；

When the actual use brightness of OLED minitype displayer is 100cd/m²When, it is micro- which can be extrapolated according to formula 2 Escope is in 100cd/m²T under brightness_1/2Value is 418408h.

S4: the mode that is used in combination calculates the service life under use pattern:

When the actual use brightness of OLED minitype displayer is in 100cd/m², the OLED minitype displayer is in the video mode With used under observation mode, the time accounting that video mode uses be 60%, the time accounting that observation mode uses be 40%, push away Calculate life value:

LT_video=2 × 0.6 × 418408+3 × 0.4 × 418408=1004179.2 (h).

S5: the service life under use pattern is in conjunction with ambient temperature projected life:

For OLED minitype displayer in the 35 degree of work of room temperature and high temperature, working and room temperature time accounting is 70%, when hot operation Between accounting be 30%, calculate the service life value of the OLED minitype displayer:

LT_video&temp=1 × 0.7 × 1004179.2+ (1/2) × 0.3 × 1004179.2=853552.32 (h).

It finally extrapolates, the OLED minitype displayer is in 100cd/m²Under brightness, in reality corresponding use pattern and Actual service life is 853552.32h under ambient temperature.

Claims

The service life evaluating method of 1.OLED display carries out life-span projection using SED model, it is characterised in that use SED first Model calculates the t under the actual use brightness of OLED display_1/2In conjunction with OLED display actual use mode and outside after value Boundary's temperature calculates its actual life, and specific formula for calculation is as follows:

LT_video&temp=LT_video× temperature factor；

LT_videoT under the=use pattern factor × actual use brightness_1/2Value；

The use pattern factor=total pixel number amount/light emitting pixel quantity；

Temperature factor numerical value is 0~1；

LT_video&tempFor the service life under use pattern and ambient temperature, LT_videoFor the service life under use pattern.
2. the service life evaluating method of OLED display as described in claim 1, feature exist:

The use pattern factor keeps its value also different because the light emitting pixel quantity under different use patterns is different Sample, light emitting pixel is more in total pixel, and the use pattern factor of the use pattern factor under 1, common use pattern is specific Numerical value such as the following table 1:

Table 1:

Use pattern The use pattern factor Video 2 Game 2 Observation 3

At different temperature, the life value of device can be under difference, especially high temperature or low temperature for the temperature factor, it Service life have reduction compared at normal temperature, in specific value such as the following table 2:

Table 2:

Ambient temperature Temperature factor - 45~-30 DEG C 1/3 - 29~-15 DEG C 1/2 - 14~0 DEG C 2/3 0-14℃ 2/3 15-29℃ 1 30-45℃ 1/2

。
3. the service life evaluating method of OLED display as described in claim 1, it is characterised in that OLED display is actually using In the process, different mode and ambient temperature switch in use, then need to combine the working time ratio under different mode, and not Working time ratio under synthermal calculates actual life, and specific formula for calculation is as follows:

LT_video&temp=LT_video× (when the work of the working time ratio of 1 × temperature of temperature factor 1+2 × temperature of temperature factor 2 Between compare ...+temperature factor N × temperature N working time ratio)；

LT_videoT under=actual use brightness_1/2Value × (working time ratio+use of 1 × use pattern of the use pattern factor 1 The working time ratio ... of 2 × use pattern of pattern factor 2+use pattern factor M × use pattern M working time ratio；

Wherein, temperature 1 arrives the sum of working time ratio of temperature N equal to 1；Use pattern 1 to use pattern M working time ratio it Be equal to 1.