LCD, LED and OLEDRay Kwong

1

Electromagnetic radiation

http://www.cyberphysics.co.uk/topics/light/emspect.htm

2

Sunlight

Calculated Solar energy striking the earth’s surface ≈ 9x10 16 W

Energy striking the earth’s surface in 2 h = 640 EJWorldwide energy consumption from all sources combined = 567 EJ (2013)1 EJ = 1018 J.

To supply enough energy for the world, we need solar panels area of 858,792 km2 .Guangdong province area = 179,757 km2

http://www.sandia.gov/~jytsao/Solar%20FAQs.pdf

http://www.helpsavetheclimate.com/solar.html

3

Electric lighting technology

http://www.edisontechcenter.org/Lighting.html

4

Alessandro Volta, Henry Woodward, Mathew Evans,Humphry Davy, James Bowman Lindsay, Moses G. Farmer, William E. Sawyer, Joseph Swan, Heinrich Göbel.

5

Carbon filamentVacuum environment

Chemical and Engineering News, May 16, 2016

6

(Inorganic) LED

http://www.edisontechcenter.org/LED.html

7

8

9

https://www.youtube.com/watch?v=ULNnxCg_SA8

LED mechanism

10

Early LEDs had no blue

LEDs

http://www.edisontechcenter.org/LED.html 11

Press Release7 October 2014The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2014 toIsamu AkasakiMeijo University, Nagoya, Japan and Nagoya University, JapanHiroshi AmanoNagoya University, JapanandShuji NakamuraUniversity of California, Santa Barbara, CA, USA“for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources"

GaAs GaAsP GaN

http://www.edisontechcenter.org/LED.html

12

https://electrical.live/2016/01/17/lighting-comparisons/ 13

14

806

9= 90 lm/W=

LCD

• History (light to see, light bulb, edison, then other light technologies)

• Mechanism (polarizing, etc)

• Chemistry

• Applications

15

http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-007-electromagnetic-energy-from-motors-to-lasers-spring-2011/lecture-notes/MIT6_007S11_lec26.pdf

16

Some examples of nematic liquid crystal compounds (http://www.tcichemicals.com/eshop/en/us/category_index/00105/)

17

http://www.connessioni.biz/en/website/categoria-tecnologie/tecnologia-lcd-inorganici-guida-alla-tecnologia-parte-1.html

http://www.ee.buffalo.edu/faculty/cartwright/teaching/ee494s99/presentations/LCD_Displays.PDF

18

http://www.amorphyx.com/technology/makingLCDs 19

http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-007-electromagnetic-energy-from-motors-to-lasers-spring-2011/lecture-notes/MIT6_007S11_lec26.pdf

20

Response time of 5-12 ms

http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-007-electromagnetic-energy-from-motors-to-lasers-spring-2011/lecture-notes/MIT6_007S11_lec26.pdf

21

OLED

http://www.edisontechcenter.org/LED.html

22

Photoluminescence

23

http://www.electronicproducts.com/Lighting/Light_Emitting_Diodes/LED_vs_OLED_a_comparison.aspx24

Picture of Galaxy S7 RGB pixels

Examples of OLED materials

http://www.displaymate.com/Galaxy_S7_ShootOut_1.htm

25

OLED fabrication

26

High vacuum~10-8 torr

Courtesy of Samsung Mobile Display

www.lgdisplay.com

https://www.youtube.com/watch?v=eatp1cOW5fQ

A look at LG’s OLED factory

https://www.youtube.com/watch?v=eatp1cOW5fQ

A look at LG’s OLED factory

Flexible OLED displayOrganic materials in OLED are non-crystalline and bendable.

www.lgdisplay.com30

Benefits of flexible OLED

31

https://www.youtube.com/watch?v=TgTMBRlnOrE