Outdoor Computing
June 18, 2015 · Comments
As I write this, I’m sitting on my patio with my laptop. It’s a lovely California summer afternoon, sunny with a cool breeze; I’ve got a glass of iced tea at my side, and nature all around. What could be a better environment for getting some coding done or catching up on research papers? Working outdoors is soothing and relaxing, conducive to concentration and creativity. There’s just one problem: I can hardly see the words I’m typing!
Everyone reading this has probably had the experience of taking their phone or laptop outside and finding the display too dark to see. Although displays have gotten a lot brighter over the last decade, the ones on consumer devices still only put out a couple hundred nits. The luminance of a piece of white paper outdoors can be over a thousand nits in the shade, and tens of thousands in direct sunlight at midday. Between the pupils of our eyes contracting and making the screen perceptually darker, and the reflected ambient light being on the order of 10–100 times brighter than the actual image, no wonder we have trouble with screens when we go outside!
(It varies with things like latitude and weather conditions, of course—you’ll have an easier time of this in Seattle than you will in Los Angeles.)
It’s possible to make brighter displays, but naturally, you very quickly run into power and heat-dissipation walls. Battery-powered devices already represent a delicately balanced trade-off between processing power, weight, battery life, and so on—so asking for 10x more power for the display is a non-starter for the foreseeable future. Eventually, batteries and displays will likely improve to the point where a portable device can make enough light to compete with the outdoors, but that may still be decades away.
For now, the only hope of a device that’s truly usable outdoors is in reflective displays. I’ve tried out some of these. I own a Sunbook laptop, which has a Pixel Qi “transflective” display—i.e. it’s an LCD with both a backlight and a reflective backplane, so you can use it like an ordinary LCD inside, but take it out and it reflects the ambient light, letting you turn off the backlight to save power. The Sunbook worked great and was a fine device for its time and purpose, but by current standards it’s hopelessly obsolete. Today, Pixel Qi is out of business and there’s no sign of any updated devices coming out with this kind of technology.
I also have a Kindle with its e-ink display. This works great for its purpose too, but the obvious disadvantage of e-ink is the very long pixel-switching latency. You’re not going to be watching a video, scrolling a website, or even typing on one of those displays. (I wish I could at least try typing on e-ink, just to see if it’s really all that bad, but AFAICT the Kindle doesn’t have any way to connect a keyboard.) E-ink devices are also pretty expensive, especially large ones like Sony Digital Paper—which I would love to try out for reading research papers, but $800 is way too much to spend for that alone. And of course, e-ink is monochrome.
Like most people, I enjoy being outdoors and would like to spend more time in the sunshine and open air while it lasts. But the work I do and many of the activities I enjoy require a computer, and that tethers me inside where it’s dark enough to see the display. The dream of “outdoor computing” is to be able to take my computer with me and use it wherever I happen to be. We’re already there in device portability and connectivity, but not yet in displays. I hope that more progress will be made in this area.
And yes, I realize this is so, so first-world of a problem to have. Oh no, my magic box that does billions of calculations per second and connects me to all human knowledge, which I have the disposable income to buy, doesn’t work perfectly well outdoors where I live in an area with one of the nicest climates in the world! Oh no! ¯\_(ツ)_/¯