Lcd
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LIQUID CRYSTAL DISPLAY
What is liquid crystal? substances that can exist in an odd state that is sort of like a liquid and sort of like a solid
Nematic Phase Liquid Crystals §There is also a variety of liquid crystal substances. Depending on the temperature and particular nature of a substance §Liquid crystals affected by electric current §Twisted nematics (TN), is naturally twisted §Electric current to these liquid crystals will untwist them to varying degrees, depending on the current's voltage. §LCDs use these liquid crystals because they react
Creating an LCD Two pieces of polarized glass. Coating of nematic liquid crystals to one of the filters. Second piece of glass with the polarizing film at a right angle to the first piece. 90-degree angle to the bottom.
Passive and Active Matrix
Passive-matrix LCDs use a simple grid to supply the charge to a particular pixel on the display Two glass layers called substrates One substrate is given as Column and another as row, these made up of transparent material indium tin oxide Liquid crystal material is sandwiched between the two glass substrates, and a polarizing film is added to the outer side of substrate. Charge to column and ground to row. Drawbacks slow response time and imprecise voltage control.
Active-matrix LCDs depend on thin film transistors (TFT). TFTs are tiny switching transistors and capacitors arranged in a matrix on a glass substrate. to address a particular pixel. Proper row is switched ON and charge is sent to particular column. rest of transistors are turned OFF Capacitor can hold charge up to another refresh cycle COLOUR LCD Three sub pixels with red, green and blue color filters to create each color pixel. 16.8 million color can produce from 3 sub pixels. For 1024 x 768 resolution screen 1024 x 768 x 3 (sub pixels ) =2,359,296 transistors
EN D
Sam suresh
What is liquid crystal? substances that can exist in an odd state that is sort of like a liquid and sort of like a solid
Nematic Phase Liquid Crystals §There is also a variety of liquid crystal substances. Depending on the temperature and particular nature of a substance §Liquid crystals affected by electric current §Twisted nematics (TN), is naturally twisted §Electric current to these liquid crystals will untwist them to varying degrees, depending on the current's voltage. §LCDs use these liquid crystals because they react
Creating an LCD Two pieces of polarized glass. Coating of nematic liquid crystals to one of the filters. Second piece of glass with the polarizing film at a right angle to the first piece. 90-degree angle to the bottom.
Passive and Active Matrix
Passive-matrix LCDs use a simple grid to supply the charge to a particular pixel on the display Two glass layers called substrates One substrate is given as Column and another as row, these made up of transparent material indium tin oxide Liquid crystal material is sandwiched between the two glass substrates, and a polarizing film is added to the outer side of substrate. Charge to column and ground to row. Drawbacks slow response time and imprecise voltage control.
Active-matrix LCDs depend on thin film transistors (TFT). TFTs are tiny switching transistors and capacitors arranged in a matrix on a glass substrate. to address a particular pixel. Proper row is switched ON and charge is sent to particular column. rest of transistors are turned OFF Capacitor can hold charge up to another refresh cycle COLOUR LCD Three sub pixels with red, green and blue color filters to create each color pixel. 16.8 million color can produce from 3 sub pixels. For 1024 x 768 resolution screen 1024 x 768 x 3 (sub pixels ) =2,359,296 transistors
EN D
Sam suresh
