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Comment by mtgx | Hacker News Reader

Why are 4k monitors and TV's so much more expensive than 1080p ones? If it's priced per pixel, they still should be only around 4x more expensive, but the current prices are much higher. I mean we're even seeing 10" 2560x1600 (2x the pixels) very high quality IPS displays in sub $500 devices, where the 10" display itself is probably $100 at most. So what's going on? Is it just the "rip off the earlier adopter with a 10x-the-cost price tag" strategy at play here?

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It's not as simple as charging per pixel. First of all, raising the resolution that high is still fairly new compared to 1080p. Lots of screens are going to come out not 100% perfect. See Catleap as evidence that lots of panels come out with defects even at non-4k resolution.

Second of all, because the screens are harder to make and prices are high because of that, adoption is lower too. With lower adoption comes lower economies of scale which mean higher prices again. So two factors at least that push prices up.

We won't see low prices until they can improve the manufacturing process enough to drop the price, which will increase adoption, which will drop the price, which will increase adoption, etc..

Good point 4x the pixels = 4x more defective pixels, given the same manufacturing.

Given that we're talking about components where more precision is needed, the odds of a defect aren't necessarily the same either.

A major factor in the cost is the defect rate. If you consider each pixel to have the same probability of being defective, you'll see that a 4k display (3840 × 2160, 8.3 megapixels) is 4x more likely to have bad pixel than a 1080p display (1920 × 1080, 2.1 megapixels).

So now the manufacturer is throwing out 4 times more units than before AND those units were already more expensive in therms of materials and time. This cost is then passed on to the consumer.

The defect rate is not 4 times as high, it is actually higher than that. If there is some probability x that a single pixel is not defective, the defect-free probability for a display is x^(width * height).

If we choose x to be 99.99999% that a single pixel is not defective, the probability of generating a defect-free 1080p (19201080) display is 81.27%, and the probability of generating a defect-free 4k (38402160) display is only 43.63%. This means that in order to produce one defect-free 1080p display, on average 1.23 displays need to be produced, and on average to produce one defect-free 4k display 2.29 displays must be produced. In pixels, this translates to 2.55e6 and 1.90e7 respectively.

The difference between the two is the number of pixels comprising 7.9377 1080p displays, about 6.4 of which would be expected to be defect free. This should indicate that the raw cost of a defect-free 4k display should be at least 6.4 times the raw cost of a defect-free 1080p display, assuming that a full display is manufactured all-at-once, and there is no interim testing to discard bad panels early, and that the cost-per-pixel of manufacture is a constant. In reality, I would expect the defect-tolerance and the pre-defect cost per pixel of the 4k display to be higher than a 1080p display. There probably is a small early-adopter penalty, but the cost isn't very out of line.

Thanks for the thorough analysis! You are totally right and I was playing too fast and loose.

It's basic economies of scale. --> http://en.wikipedia.org/wiki/Economies_of_scale

So the actual view point is that the intention isn't to "rip off the early adopter". It is that the early adopter isn't subsidized by a product that is produced in volume.

Here is the simple theory: - Buy 1 Custom T-shirt = $50/unit - Buy 10,000 of the same "Custom" T-shirt = $5/unit

Is the person who pays for a custom t-shirt being ripped off? Taking all things into consideration, No.

Have you considered that 4x the pixels means 4x the pixel density? This is going to make them rather more difficult to manufacture, I'd think.

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