Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

9.7 Active Circular Polarizer OLED E-Mirror

497 views

Published on

Presented by Visteon's Paul Weindorf at the Society for Information Display (SID) Vehicle Displays and Interfaces 25th Annual Symposium.

Published in: Automotive
  • Be the first to comment

  • Be the first to like this

9.7 Active Circular Polarizer OLED E-Mirror

  1. 1. Visteon Confidential 9.7 Active Circular Polarizer OLED E-Mirror Paul Weindorf, Qais Sharif, Elijah Auger, Brian Hayden, Pedro Coutino Soto
  2. 2. Agenda • E-Mirror Overview • E-Mirror Toggle Overview • E-Mirror Technologies • E-Mirror Technology Comparison • OLED E-Mirror Technology • OLED Active Circular Polarizer Solutions • Active Polarizer Performance • Active Polarizer Simulation • Active Polarizer Performance Pictures • Active Circular Polarizer Reflectance Data • Active Polarizer Analysis • Active Circular Polarizer OLED E-Mirror Estimated Performance • Summary/Conclusion 2
  3. 3. E-Mirror Overview 3 Footer Switch Front Bezel Lens Assembly Button Assembly Rear Sensor Display Main PWB Flex Rear Cover Figure 1-1. Electronic Display Mirror Assembly
  4. 4. E-Mirror Toggle Overview 4 Footer • 4° toggle is required to eliminate ghost car light images at night Figure 2-3. Mirror Toggle Lever Depiction [5, Fig. 2]
  5. 5. E-Mirror Technologies 5 Footer Electrochromic Absorber Half Mirror 50% Reflection 50% Transmission Display 50% Reflection Big Problem Always reflecting in display mode causing double image! 50% Transmission Figure 2-1. Electrochromic E-Mirror System 0 10 20 30 40 50 60 70 80 0 0.5 1 %TransmissionorReflectance Drive Voltage EC Transmission EC Reflectance 0 10 20 30 40 50 60 70 80 0.0 5.0 10.0 15.0 20.0 %TransmissionorReflectance Drive Voltage Trans Phase 3 Final OCA+AR Lens SCI Phase 3 Final OCA+AR Lens Figure 2.4-1. AlphaMicron Configuration Reflective Polarizer TFT Display Front Linear Polarizer TFT Display EC Element Reflective Polarizer TFT Display Front Linear Polarizer TFT Display Figure 2.2-1. Reflective Polarizer + EC Element Figure 2.1-1. Reflective Polarizer Only Reflective Polarizer TFT Display Front Linear Polarizer TFT Display LC Rotator Cell Front Linear Polarizer Figure 2.3-1. Reflective Polarizer plus LC Shutter
  6. 6. E-Mirror Technology Comparison 6 Footer Lighting Condition TFT or Mirror Mode Parameter Half Mirror +EC (Gentex) Reflective Polarizer Alone Reflective Polarizer +EC Reflective Polarizer +LC Shutter Reflective Polarizers +Rotator +Active Polarizer (AlphaMicron) Daytime Mirror Reflectance 45.5% 44% 44% 44% 74% Daytime TFT TFT Polarized Light Transmission 38.6% 90% 90% 90% 75.4% Daytime or Nighttime TFT Ghost Image Reflectance 45.5% 44% 44% 4% 10% Nighttime Mirror Dimming Reflectance Range 6.3%→45.5% 44% 6%→44% 4%→42% 10%→74%
  7. 7. OLED E-Mirror Technology OLED E-Mirror Provides: • Lower Weight • Thin Profile (no backlight) • Higher Color Gamut • Higher Reflectance • Lower Power • Thinner Borders 7 Footer LGD Display OLED Mirror at 2017 SID Exhibition
  8. 8. OLED E-Mirror Technology • OLED E-Mirror without circular polarizer reflectance @ 75% is unacceptably high for display mode even with toggle • Auto-dimming function not available 8 Footer Figure 4-3. OLED Reflection Diagram [10] Figure 4-4. OLED Circular Polarizer Diagram [11]
  9. 9. OLED E-Mirror Active Circular Polarizer Solutions 9 Footer Active Polarizer λ/4 Retarder OLED Display Figure 4.1-1. Active Polarizer Configuration Passive Polarizer Active Retarder OLED Display Figure 4.2-1. Active Retarder Configuration
  10. 10. Active Polarizer Performance 10 Footer Figure 4.1-2. Unpolarized Light Transmission Measurement (no reference polarizer) Figure 4.1-3. Polarized Light Transmission Measurements (with reference polarizer) 0 10 20 30 40 50 60 70 80 90 100 0 2 4 6 8 10 12 14 16 18 Transmittance(%) Differential Voltage (v) Unpolarized n/a 0 10 20 30 40 50 60 70 80 90 100 0 2 4 6 8 10 12 14 16 18 PolarizedTransmittance (%) Differential Voltage (v) || Polarized X Polarized
  11. 11. Active Polarizer Simulation 11 Footer Figure 4.1-7. Transmission Simulation Curves as a Function of Dye Doping Levels
  12. 12. Active Polarizer Performance Pictures 12 FooterFigure 4.1-9. Polished Silicon Wafer Reflector AP + RetarderActive Polarizer ONLY Figure 4.1-10. Active Polarizer in Off Condition AP + RetarderActive Polarizer ONLY Figure 4.1-11. Active Polarizer in On (Driven) Condition Figure 4.1-12. Reflective Mirror Data
  13. 13. Active Circular Polarizer Reflectance Data 13 Footer 0 5 10 15 20 25 30 35 40 0 5 10 15 20 %Reflectance Drive Voltage ACP SCI Mirror SCI Figure 4.1-13. Active Circular Polarizer (ACP) Reflectance versus Drive Voltage. ID ACP SCI (Y) x y AP_RET_MIR_00v 32.76 0.3047 0.3239 AP_RET_MIR_01v 32.77 0.3047 0.324 AP_RET_MIR_02v 32.76 0.3047 0.324 AP_RET_MIR_03v 32.76 0.3047 0.324 AP_RET_MIR_04v 32.75 0.3047 0.324 AP_RET_MIR_04.5v 32.68 0.3048 0.324 AP_RET_MIR_05v 31.4 0.3051 0.3239 AP_RET_MIR_05.5v 28.41 0.306 0.3236 AP_RET_MIR_06v 25.98 0.3066 0.3231 AP_RET_MIR_07v 22.38 0.307 0.3216 AP_RET_MIR_08v 20.12 0.3068 0.3202 AP_RET_MIR_09v 18.5 0.3065 0.3187 AP_RET_MIR_10v 17.75 0.3063 0.318 AP_RET_MIR_11v 17.05 0.306 0.3173 AP_RET_MIR_12v 16.6 0.3058 0.3168 AP_RET_MIR_13v 16.26 0.3057 0.3164 AP_RET_MIR_14v 15.91 0.3055 0.316 AP_RET_MIR_15v 15.72 0.3054 0.3158 AP_RET_MIR_16v 15.55 0.3053 0.3157 AP_RET_MIR_17v 15.36 0.3052 0.3153 Table 4.1-2. Active Circular Polarizer Reflectance Data
  14. 14. Active Polarizer Analysis 14 Footer LI 0.04LI 0.96xTx0.04xTx0.96xLI T Active Polarizer λ/4 Retarder Si Wafer Mirror (35.22% Reflection) Air Gap 0.96xTx0.96x0.3522x0.96xTx0.96xLI Figure 4.1-14. Un-Driven State Model 2 2 4 _0.04 0.04 0.96 0.3522 0.96M X OFFR T        2 2 4 0.04 0.868 0.04 0.96 0.3522 0.96 29.3% M M R R         Measured 32.7% LI 0.04LI 0.96xT||x0.04xTX_ONx0.96xLI T Active Polarizer λ/4 Retarder Si Wafer Mirror (35.22% Reflection) Air Gap 0.96xT||x0.96x0.3522x0.96xTX_ONx0.96xLI Figure 4.1-15. Driven State Model 2 4 _ _0.04 0.04 0.96 0.3522 0.96M X ON X ONR TT TT  P P       2 4 0.04 0.04 0.868 0.304 0.96 0.3522 0.868 0.304 0.96 12.8% M M R R     Measured 15.36%
  15. 15. Active Circular Polarizer OLED E-Mirror Estimated Performance A rough estimate of the actual OLED performance can be accomplished by: • Subtracting 4% front surface reflectance from each of the values in Table 4.1-2 • Rescaling by the factor 75%/35.22% • Adding the 4% front surface reflectance back. 15 0 10 20 30 40 50 60 70 0 5 10 15 20 %Reflectance Drive Voltage Si Wafer SCI OLED SCI Figure 4.1-16. Estimated OLED SCI Performance with an Air Gap System
  16. 16. Summary/Conclusion 16 Footer OLED w/o Circular Polarizer Active Polarizer Active Retarder Transmission 100% 56.2% 40% Luminance (cd/m²) 600 337 240 Max Reflectance 75% 56% 52% (AR) 30% 26% (AR) Min Reflectance 75% 22% 18% (AR) 4% 0% (AR) Cost Lowest Medium Medium Table 4.3-1. Configuration Summary • Active polarizer is preferred over active retarder to meet NTSC minimum reflectance requirement of 35%. • Active polarizer minimum reflectance should be lowered at the expense of maximum luminance to provide better dimming performance • Active polarizer may be operated in the OLED maximum transmission unpolarized state of 83.3% or down to the minimum polarized transmission of 56.2% • Active Polarizer technology will enable OLEDs to be used as a dimmable mirror or as a display.

×