Howdy from a noob with questions: help me understand transflective displays
I can't believe I hadn't found this site sooner. I'm in the planning phase of building a CarPC for my Twin Turbo Dodge Stealth, and this site has already been a great resource.
I've been very impressed with the mp3car transflective displays, and I'm trying to get a handle on the details of transflective technology and why it works the way it does. I understand the basic principle of using a semi-silvered mirror to allow the sun to act as a reflected natural backlight, and using an anti-reflective coating to eliminate reflected images, but I have questions about the stack-up.
I found some good info in this FAQ -> http://www.mp3car.com/vbulletin/lcd-...echnology.html
My question is this: What is the purpose of the AR coating between the LCD and the polarizer? It seems that any reflected images off of the exterior surface of the polarizer would be handled by the outermost AR coating. Does it have something to do with uneven reflected light from the 1-way mirror? But then, a normal diffuser behind the LCD should be able to deal with that.
Transflective LCD - a process of removing the polarizer (in a clean room (you know white neumaticly sealed suits like at NASA)) adding a (sometimes 3M) AR coating to the interior layer of the lcd, and adding a reflective layer albeit transmissive film (like a two way mirror or one way glass) in front of the backlight, ie:
backlight > one way light coating > lcd > AR coating > polarizer > AR coating
this diagram is quite simplified however you should get the idea.
Next question: What drives that AR coating to be in between the LCD and the front polarizer? Would it perform the same function (whatever that function is) behind the LCD? I noticed that the FAQ left out the rear polarizer behind the LCD. Does the AR coating need to be between the polarizers for some reason? In other words, are these 3 options optically identical?
I hope someone can help me understand this. :confused:
backlight > one way mirror > polarizer > LCD > AR coating > polarizer > AR coating
backlight > one way mirror > polarizer > AR coating > LCD > polarizer > AR coating
backlight > one way mirror > AR coating > polarizer > LCD > polarizer > AR coating