Slashdot Mirror
Ask Slashdot: Where Are the E-Ink Dashboards?
fsck! writes "My office recently installed a pair of huge plasma TVs to display some metrics and graphs. They only update every 15 minutes or so, and I couldn't help but wonder, why can't this be E-Ink? I searched all over the place but couldn't find anything bigger than 9.5" (Amazon's Kindle DX). I want a >30" E-Ink picture frame with USB or WiFi. Can the Slashdot community find anything greener than these energy sucking plasma TVs that seem to be everywhere?"
I currently work in a call centre while I'm studying.
They have 4 large LCD screen in the centre of the rooms, facing outwards. These screens only show how many people are on the phones and how many customers are waiting. This display is updated every 15 seconds.
A large e-Ink display would be perfect for this. There is no colour needed and should save a fair chunk of power. That is, of course, I'm mistaken about the energy usage of e-ink displays?
Surely someone has created one if that is the case? Surely there would be a market for it now? And if you needed a bit of colour, I'm sure basic colour e-ink displays can do the job fine.
How about a giant Raspberry Pi-powered etch-a-sketch?
The video isn't very good, and it's not giant, but: http://www.raspberrypi.org/archives/3046
It's not $8. Those numbers came from probably very conservative assumptions about how much the average TV buyer actually uses his TV, which probably isn't 24 hours/day (or even 8-16 hours, as you might expect for a TV being used as an in-office "dashboard"). I'm guessing their assumption might be 2 hours/day.
I just did some very rough calculations: if the TV is going to be on 2 hours/day on average, that's 730.5 hours/year. If the TV uses 100W when operating, that's about 73kWh over the whole year. If your power costs $0.20/kWh, then the TV will cost $14.61 to operate for one year.
I'd assume that these "dashboard" TVs will be operated 10-12 hours a day, which is 5-6 times those previous numbers. Plus, commercial electricity costs more than residential, IIRC (I could be wrong about that). So it's probably much closer to $100/year to run these TVs, or maybe more. Still not an astronomical amount of money, though.
What I want to know is: what kind of TVs is the submitter using anyway? He's apparently interested in an e-Ink screen that's 30 FEET diagonally.
If Sharp really do deliver on their promises, IGZO panels are going to dominate in the next few years. Like e-ink they don't require power for a static image and can be transparent, but unlike e-ink IGZO has fast response/refresh rates and supports high resolutions! There's a 32" 4K coming next month rumoured to be $5,500 US launch price. It's the same panels that caused Apple to release Plan B for the iPad 3.
TLDR; Check out this (cheesy) video where IGZO introduces "himself" http://www.youtube.com/watch?v=SnUUXoFsjoY
The fabrication costs for 30" are too high.
The way these things are fabricated results in a sufficien number of pixel failures in a 30" display as to make it uneconomical.
They are typically fabricated in large sheets, then the sheets are tested for dead pixels, and then the standard display sizes are cut out from between the dead pixels, and the individual units are retested. The smallest display sizes are used for things like watches and digital thermometers, etc..
The fabrication process has barely improved enough that they can (as of very recently) offer 9.74" displays in quantity sufficient to make them worth manufacturing.
Unless you can personally improve the process/methods to significantly improve yields for larger areas of the sheets, then what you are asking for will remain uneconomical, probably for several decades, as process improvements in LCD, LED, and OLED continue to outstrip E-Ink, and therefore their power consumption costs drop toward that of E-Ink. Currently, the only practical value for E-Ink is power consumption for infrequently updated displays which tend to be power sensitive only because they run off batteries.
So the short answer is you haven't personally invented the fabrication processes yet.
Here's a direct comparison for you, from my local power company (the largest hydroelectric producer in the world, HydroQuebec) all prices in CAD, and I'm ignoring the fixed costs here:
Residential rate: /kWh /kWh
Power over 50 kW (winter): $6.21 / kW
Power over 50 kW (summer): $1.26 / kW
First 30 kWh per day: 5.32
Remaining consumption: 7.51
Business rates ("low power", below 100 kW every month): /kWh /kWh
Power over 50 kW: $15.54 / kW
First 15,090 kWh: 8.73
Remaining consumption: 4.85
Business rates ("medium power", at least one month a year over 50 kW): /kWh /kWh
Power over 0 kW: $13.44 / kW
First 210,000 kWh: 4.41
Remaining consumption: 3.19
Business rates ("Large power", every month over 5 megawatts): /kWh
Power over 0 kW: $12.18 / kW
All consumption: 2.95