Quote:
Originally Posted by karunaji
Generally, bigger things are cheaper to produce per each sq. inch. Why it should be different for e-ink?
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In mechanical manufacturing, yes.
But not in the world of electronics.
In semiconductor manufacturing, each facility is designed to work at a specific scale for the elements it can make. The size of the elements that go into the manufactured devices stays the same and to go bigger you simply put more of them together in an array.
As Murraypaul pointed out, putting more elements in an array means more chances for elements within the array to go wrong and since the product is useless if too many (sometimes too many = 1) the cost per *good* unit goes up with the size of the device manufactured. (Larger devices also consume more power and generate more waste heat than equivalent devices built to smaller scales.)
(The scale of element manufacturing is referred to as the process. For example, the XBOX CPU and GPU were first introduced at 90nm scale and over time migrated to 65nm and even 45nm. In the process they became significantly *cheaper* to manufacture and consume less power, generate less heat, and are more reliable.)
It also helps to understand that in eink displays, the pixels in the quoted resolutions are made up of dozens/hundreds of the actual eink particles. So making bigger displays means each pixel is going to be made of more of the color-shifting elements; doubling the size means four times the number of elements and four times the odds of getting manufacturing defects.
Check this:
http://en.wikipedia.org/wiki/File:El...c_display).PNG
From the wikipedia eink article:
http://en.wikipedia.org/wiki/E_Ink
Also check this:
http://en.wikipedia.org/wiki/Electro...lectrophoretic
Making the basic electrophoretic eink film in large sizes isn't the issue.
http://www.the-digital-reader.com/20...-a-300-screen/
Attaching the electrodes and electronics and getting usable products is.
Again: it is about the cost of developing&manufacturing the product versus the size of the potential market. The demand out there doesn't justify the investment; there simply aren't all that many people who would willingly pay US$1000 for it even if it existed. Most would rather put up with LCD at one-tenth the cost.