Making a Liquid Crystal Display

Quick Overview of How Liquid Crystal Displays Work


Display Layers

Thin Film Transistors (TFT) act like a dimmer switches


Florescent or LED backlighting is required.

The light goes through layers of glass, polarizers, thin film transistors (TFT), liquid crystals, and color filters.

The Thin Film Transistors adjust the amount of light that passes through the color filters by controlling the liquid crystals. 

The colors and light combine to produce the images you see on your display.


Today’s Manufacturing Process of LCD Displays with TFTs

Manufacturing an LCD panel is a high-precision process requiring over 300 individual steps. Typically referred to as TFT-LCD process, putting together an LCD display requires a Class-10 level of cleanliness, where less than 10 particles of dust per cubic feet may be in the room. The TFT-LCD process has three sub-processes: (Click here to watch a short video about this process.)

The Array Process:          1. Thin Film 2. Photolithography 3. Etching 4. Stripping

The Cell Process:            5. Polyimide Printing 6. Rubbing 7. Spacer Spread 8. Liquid Crystal Dispensing 
                                             9. Assemble and Seal 10. Polarization Lamination

The Module Process:     11. COG Process 12. FPC Attachment 13. PCB Mounting 14. Backlight Mounting
                                             15. Aging (Testing)

The array process is where TFT (dimmer switches) are applied. The back-glass substrate is patterned with interconnected rows and columns of TFTs, and the front-glass substrate is combined with a color filter. Depositing substances to fabricate the thin film is repeated for each of the required six layers of crystalline or semiconductor metal. This is done using a plasma-enhanced chemical vapor deposition (CVD) device, the same tool needed to deposit only two layers of Amorphyx’s AMNR.

Following this is the cell process where the TFTs and color filter glass plates are attached together with the liquid crystals. The whole panel module is later assembled with all electronics and connections.