Motion blur on 2D dimming backlight and motion picture simulation Motion blur on 2D dimming backlight and motion picture simulation Speaker: Chi-Wei Chen ( 陳致維 ) Advisor: Prof. Yi- Pai Huang ( 黃乙白 教授 ) Display Institute, National Chiao Tung University, Hsinchu, Taiwan March

2 Advanced Display Optics Lab Outline  Introduction  Motivation and Concept  Simulations  Future works  Conclusions

3 Advanced Display Optics Lab Outline  Introduction  Motivation and Concept  Simulations  Future works  Conclusions

4 Advanced Display Optics Lab Introduction What causes motion blur ? - Slow liquid crystal response and nature of hold type display - Smooth pursuit results in edge blurring V (pixels/frame)

5 Advanced Display Optics Lab Conventional : t (LC response time) LC response curve BL Final Motion blur Motion blur on conventional backlight t (LC response time) luminance (nits) 500 nits Transmission (%) 80% (origin : 400 nits) 400 nits 10% 90% pixel

6 Advanced Display Optics Lab The solvents Blinking backlight, black insertion. Faster LC response, overdrive. Original image Blur image With black insertion Prior art : ~~ SID 02 Daigo Sasaki, etc. Disadvantage: - The image with black insertion is darker than the original image !

7 Advanced Display Optics Lab Outline  Introduction  Motivation and Concept  Simulations  Future works  Conclusions

8 Advanced Display Optics Lab Motivation Brightness between original and final image still the same. The motion blur effect is improved.

9 Advanced Display Optics Lab Concept 2-D dimming backlight : (120Hz) (origin : 400 nits) BL Final Motion blur LC response curve 500 nits 100 nits Transmission (%) luminance (nits) 80% t (LC response time) pixel 400 nits 10% 90%

10 Advanced Display Optics Lab Outline  Introduction  Motivation and Concept  Simulations  Future works  Conclusions

11 Advanced Display Optics Lab Motion picture Simulation system Time Position (pixel) Temporal integration considered a smooth pursuit Eye movement frame 1 Brightness LC response curves between grayscales Time Object velocity : v (pixels/frame) v The formation of a response curve for each pixel

12 Advanced Display Optics Lab Simulation with 2D dimming backlight Original image Algorithm BL (dim) BL (boost) BL : 8X8 areas (average) LC : compensation Final image Backlight (BL) LC compensation x x 1st frame 2nd frame Brightness Time 12 BL(dim) BL(boost) Brightness Time Less motion blur BL (dim) BL (boost) Gray level

13 Advanced Display Optics Lab Motion picture response time (MPRT) The BEW (brightness edge width) is proportional to the moving speed. N-BEW (frame)=BEW (pixel) / moving speed (pixel/frame) N-BET (ms) = N-BEW x frame rate (seconds/frame) (MPRT) 10% 90% BEW A A A’ Motion picture response curve pixel luminance ~~ SID 04 Youichi Igarashi, etc.

14 Advanced Display Optics Lab Simulation results Motion blur 10% 90% Motion blur 10% 90% V=20(pixels/frame) With 2D dimming BL Full on BL MPRT= 18 ms MPRT= 15.8 ms

15 Advanced Display Optics Lab Simulation results V=10(pixels/frame) With 2D dimming BL Full on BL Motion blur 10% 90% Motion blur 10% 90% MPRT= 14 ms MPRT= 11.7 ms

16 Advanced Display Optics Lab Simulation results V=10(pixels/frame) With 2D dimming BL Full on BL Motion blur 10% 90% MPRT= 14 ms MPRT= 8.4 ms Motion blur 10% 90%

17 Advanced Display Optics Lab Outline  Introduction  Motivation and Concept  Simulations  Future works  Conclusions

18 Advanced Display Optics Lab Future works (1)Find the better BL control method. (2) Simulate with other complex pictures.

19 Advanced Display Optics Lab Outline  Introduction  Motivation and Concept  Simulations  Future works  Conclusions

20 Advanced Display Optics Lab Conclusions Improve the motion blur effect Keep the brightness 2D dimming backlight :

21 Advanced Display Optics Lab Thanks for your kind attention

22 Advanced Display Optics Lab Simulation method Step 1: Find the LC response curves of different gray-to- gray level. (under conventional BL)  Find the motion blur areas LC response curve Transmission (%) t (LC response time) 100% 80% 50% 30%

23 Advanced Display Optics Lab Simulation method Step 2 : Get the 2D dimming BL  BL1(dark) & BL2(bright) The target : 1. Brightness between original and final image still the same. 2. the motion blur appearance is improved. BL1(dark)+ LC compensation BL2(bright)+ LC compensation + ÷2÷2 Final image original image