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Halla Visteon Climate Control
Yanfeng Visteon
Electronics
Interiors
Our Familyof Businesses
Strictly Private and Confidential
Visteon: Paul Weindorf, Daniel AndresFutaba: Jeff Hatfield
6.1: Automotive OLED Life Test and Prediction
Halla Visteon Climate Control
Yanfeng Visteon
Electronics
Interiors
Our Familyof Businesses
ElectronicsOutline
Introduction
Organic Light Emitting Diode (OLED) display life test description
OLED life test results
Automotive life test prediction
Vacuum Fluorescent (VF) display comparison example
Conclusions
Page 2
Collaborative effort between Visteon and Futaba corporations
ElectronicsIntroductionOLED advantages:
1. Higher contrast ratios2. Superior color and contrast viewing angle performance3. No black background “bleed”4. Better reflection performance5. Substantially better power performance
OLED disadvantage – Differential aging (burned-in image)
Page 3
ElectronicsOLED Life Test Description – Futaba EL427 OLED
Page 4
Futaba EL427 OLED
1. Passive matrix automotive OLED2. Duty – 1/643. Color – White4. Luminance – 300 cd/m2 with circular polarizer5. 4 gray shades
ElectronicsOLED Life Test Description – Initial Measurements
Page 5
A B
CD
E
OLEDID
MeasurementLocation
(drive level)
cd/m2 x y
#1 A (L3 drive) 130.4 0.3027 0.3113
#1 B (L2 drive) 56.91 0.3014 0.3107
#1 C (L1 drive) 1.081 0.3142 0.3072
#1 D (L4 drive) 275.7 0.3022 0.3090
#1 E (all white L4) 269.3 0.2990 0.3070
#1 E (all black L1) 0.002285 0.3931? 0.3111?
#2 A (L3 drive) 132.4 0.3051 0.3134
#2 B (L2 drive) 57.84 0.3039 0.3129
#2 C (L1 drive) 1.103 0.3151 0.3086
#2 D (L4 drive) 284.2 0.3003 0.3103
#2 E (all white L4) 281.0 0.3029 0.3147
#2 E (all black L1) 0.003906 0.3509? 0.3045?
#3 A (L3 drive) 133.2 0.3055 0.3120
#3 B (L2 drive) 58.77 0.3038 0.3123
#3 C (L1 drive) 1.115 0.3160 0.3083
#3 D (L4 drive) 285.2 0.3016 0.3083
#3 E (all white L4) 279.5 0.3002 0.3085
#3 E (all black L1) 0.003346 0.3412 0.3001
ElectronicsOLED Life Test Description - Light Sensor Frame
Page 6
Light Sensor Current to Voltage Converter (Light Sensor and Amplifier)
Osram Light Sensor
System Block Diagram
Light Sensor Frame Assembly
ElectronicsOLED Life Test Results
Page 7
Raw Life Test Data
0
100
200
300
400
500
600
700
800
900
1000
0 5000 10000
Ligh
t Sen
sor A
/D C
ount
s
Hours
Room Temp:1/2Vref
Room Temp:LS4
Room Temp:LS3
Room Temp:LS2
Room Temp:LS1
60C:1/2 Vref
60C:LS4
60C:LS3
60C:LS2
60C:LS1
85C:1/2 Vref
85C:LS4
85C:LS3
85C:LS2
85C:LS1
Visteon (blue circle) versus Futaba Correlation
• Luminance decay rate increases as the operational temperature is increased.
• Very good correlation between Visteon and Futaba life test data.
ElectronicsOLED Life Test Results
Page 8
Drive
Zone
Temp, OLED ID#
Y InitialYFinal
L4
D 25°C, #1
275.7 151.2
L4 All White
D 25°C, #1
269.3 148.5
L3
A 25°C, #1
130.4 98.36
L4 All White
A 25°C, #1
269.3 204.1
L2
B 25°C, #1
56.91 54.13
L4 All White
B 25°C, #1
269.3 254.9
L1
C 25°C, #1
1.081 0.9753
L4 All White
C 25°C, #1
269.3 300.3
L4
D 60°C, #2
284.2 89.78L4 All White D 60°C, #2 281 83.94
L3
A 60°C, #2
132.4 72.69L4 All White A 60°C, #2 281 152.6
L2
B 60°C, #2
57.84 45.64L4 All White B 60°C, #2 281 228
L1
C 60°C, #2
1.103 0.5849L4 All White C 60°C, #2 281 306.2
L4
D 80°C, #3
285.2 26.96
L4 All White
D 80°C, #3
279.5 16.62
L3
A 80°C, #3
133.2 33.69
L4 All White
A 80°C, #3
279.5 57.79
L2
B 80°C, #3
58.77 33.06
L4 All White
B 80°C, #3
279.5 177.3
L1
C 80°C, #3
1.115 0.3836
L4 All White
C 80°C, #3
279.5 295.6
Final OLED Data after Life Test
0
50
100
150
200
250
300
350
L4
(2
5°C)
L4 W
hite
(25°
C)L3
(25°
C)L3
Whi
te (2
5°C)
L2
(2
5°C)
L2 W
hite
(25°
C)L1
(25°
C)L1
Whi
te (2
5°C)
L4
(6
0°C)
L4 W
hite
(60°
C)L3
(60°
C)L3
Whi
te (6
0°C)
L2
(6
0°C)
L2 W
hite
(60°
C)L1
(60°
C)L1
Whi
te (6
0°C)
L4
(8
5°C)
L4 W
hite
(85°
C)L3
(85°
C)L3
Whi
te (8
5°C)
L2
(8
5°C)
L2 W
hite
(85°
C)L1
(85°
C)L1
Whi
te (8
5°C)
Lum
inan
ce (c
d/m
^2)
Y Initial
Y Final
Futaba Shelf Life Data
ElectronicsOLED Life Test Results - Color
Page 9
Drive (Zone,Temp,ID#) x Initial y Initial
x Final
y Final
L4 (D,25°C,#1) 0.3022 0.309 0.3313 0.3255L4 All White(D,25°C,#1) 0.299 0.307 0.3287 0.3237
L3 (A,25°C,#1) 0.3027 0.3113 0.318 0.3197L4 All White (A,25°C,#1) 0.299 0.307 0.3141 0.3173
L2 (B,25°C,#1) 0.3014 0.3107 0.3102 0.3159L4 All White(B,25°C,#1) 0.299 0.307 0.3115 0.3146
L1 (C,25°C,#1) 0.3142 0.3072 0.2934 0.2935L4 All White(C,25°C,#1) 0.299 0.307 0.3052 0.3119
L4 (D,60°C,#2) 0.3003 0.3103 0.3681 0.3439L4 All White(D,60°C,#2) 0.3029 0.3147 0.3648 0.3419
L3 (A,60°C,#2) 0.3051 0.3134 0.3444 0.3316L4 All White(A,60°C,#2) 0.3029 0.3147 0.3436 0.3307
L2 (B,60°C,#2) 0.3039 0.3129 0.3262 0.3236L4 All White(B,60°C,#2) 0.3029 0.3147 0.3282 0.3255
L1 (C,60°C,#2) 0.3151 0.3086 0.3088 0.3029L4 All White(C,60°C,#2) 0.3029 0.3147 0.3138 0.3174
L4 (D,85°C,#3) 0.3016 0.3083 0.4548 0.3846L4 All White(D,85°C,#3) 0.3002 0.3085 0.4469 0.3792
L3 (A,85°C,#3) 0.3055 0.312 0.3945 0.3531L4 All White(A,85°C,#3) 0.3002 0.3085 0.3924 0.352
L2 (B,85°C,#3) 0.3038 0.3123 0.3487 0.3324L4 All White(B,85°C,#3) 0.3002 0.3085 0.3491 0.3319
L1 (C,85°C,#3) 0.316 0.3083 0.406 0.3465L4 All White(C,85°C,#3) 0.3002 0.3085 0.329 0.3239
0.20.220.240.260.28
0.30.320.340.360.38
0.4
0.2 0.3 0.4 0.5
y
x
y Initial
y Final
ElectronicsAutomotive Life Prediction – Consumption Rates
Page 10
0
100
200
300
400
500
600
700
800
900
1000
0 2000 4000 6000 8000 10000
Ligh
t Sen
sor A
/D C
ount
s
Hours
Room Temp:LS4
Room Temp:LS3
Room Temp:LS2
60C:LS4
60C:LS3
60C:LS2
85C:LS4
85C:LS3
85C:LS2
LS4 25C Predict
LS4 60C Predict
LS4 85C Predict
LS3 25C Predict
LS3 60C Predict
LS3 85C Predict
hourcounts
KCC
CR op
5.10751042.61.0
310max
2
hournits
KLL
CR op
5.10751042.61.0
310max
2
Consumption Rate Formulas
hournits
eLL
CRt
op
1076403181042.6
1.03
15.010max
2
Cop= operating A/D countCmax= maximum display A/D count
Lop= operating luminanceLmax= maximum display luminance
hourcounts
eCC
CRt
op
1076403181042.6
1.03
15.010max
2
Add exponential temperature decay
• Exponential temperature decay• 85°C hot start• 45°C steady state• 0.15 hours time constant
ElectronicsAutomotive Life Prediction - Luminance Degradation
Page 11
dtCRLDt
0
tfLL
CR op max
2
1076403181042.6
1.03
15.010
te
tf
TCt
S effftf
0
TCt
S etf 44 1001.21008.1
0
0.00005
0.0001
0.00015
0.0002
0.00025
0.0003
0.00035
0 0.5 1
f(t)
Hours
f(t)fs(t)
Luminance degradation is the integral of consumption Rate
TC=0.1Curve Fit fS(t) versus f(t)
t t t
Sop
Sop dttf
CC
dttfCC
CRdtLD0 0 0max
2
max
2
nitsetLDt
1.010056.00301.0
• Each hot start from +85°C consumes 0.0056 nits of luminance
• Each steady state hour of operation at 45°C consumes 0.0301 nits of luminance
ElectronicsAutomotive Life Prediction – Example 1
Page 12
Condition Luminance Decrease
Notes
3650 +85°C hot starts
20.44 nits 20.44=3650x.0056
2500 hours @ 280 nits day time operation
75.46 nits 75.46=2500x0.030184
2500 hours @ 40 nits night time operation
1.54 nits 1.54=2500x0.000616
Total luminance decrease @ end of life
97.44 nits 34.8% decrease from the initial 280 nits
• 10 years at 15K miles/year (150K miles total)• Average speed of 30 mph• 5000 hours total number of operational hours• 3650 hot (85°C) summer starts (2 hot starts/summer day)• 45°C steady state operation
Condition
Luminance Decreasecd/m2 Notes
3650 +85° hot starts 1.08 1.08=3650x0.000295
2500 hours @ 300 nits day time operation 9.13 9.13=2500x0.003653
2500 hours @ 40 nits night time operation 1.22
1.22=2500x0.001461x40/300
Total luminance decrease @ end of life 11.43
3.81% decrease from initial 300 nits
VF Display Automotive Life ExampleOLED Display Automotive Example
ElectronicsAutomotive Life Prediction – Example 2
Page 13
Condition Luminance Decrease
Notes
3650 +85°C hot starts
19.345 nits 19.345=3650x.0053
2500 hours @ 280 nits day time operation
52.5 nits 52.5=2500x0.021
2500 hours @ 40 nits night time operation
1.05 nits 1.05=2500x0.00042
Total luminance decrease @ end of life
72.9 nits 26% decrease from the initial 280 nits
• 10 years at 15K miles/year (150K miles total)• Average speed of 30 mph• 5000 hours total number of operational hours• 3650 hot (85°C) summer starts (2 hot starts/summer day)• 25°C steady state operation
ElectronicsConclusions
Futaba OLED displays operated successfully for 10,000 hours at 25°C, 60°C & 85°C.
Prediction method using life test data was developed to predict the aging performance for a worst case automotive life cycle.
Most of the OLED display luminance degradation is a result of daytime steady state operation and not due to hot starts or high temperature storage.
The aging prediction indicates that the Futaba OLED display image burn-in performance is worse than matrix type VF displays.
It is expected that the Futaba OLED display may be successfully utilized for automotive applications with appropriate counter measures.
Page 14
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