I have a convertible tablet laptop that uses WACOM. I have been trying to figure out how it works, and most searches come up with how to use it rather than the underlying technology.
For those not familiar with it, it works like a touchscreen, but the screen is not responsive to the touch of anything but the special stylus that comes with it. The stylus is a plastic pen-sized instrument with a small replaceable plastic (?) tip. The screen responds to the stylus when it’s within about an inch of the screen. Some applications with inking capability such as Word show that there is some pressure sensitivity (line gets thicker as you press harder). The manual says not to get the stylus wet because it has active electronics, but there are no batteries for it.
So how does the stylus communicate with the screen?
WACOM is a brand, rather than a technology (or that’s what I thought).
They work electromagnetically - a grid of wires is buried under the active surface and these induce a current in the pen, which transmits a signal that is picked up by the same grid of wires - a bit like RFID security tags, only with more precision.
I think it’s just that they’ve pretty much cornered the market, especially the lower-priced end of it. They doubtless have some patents on parts of their implementation though.
Wacom had a patent on the technology, but it expired a few years ago. Since then, there have been some inexpensive tablets producing price pressure on Wacom. But even though the main patent has expired, they have done considerable research and development on improving the technology and have plenty of additional patents.
Summagraphics tablets were corded, and Calcomp used watch batteries. Both sucked and quite rightly vanished when the Wacoms appeared. Wacoms have 1024 levels of pressure, most of their pens are active on both ends of the barrel - the tip and an “eraser” (which can be set to any paint tool.) Few programs use the tilt feature, but the MIT Media Lab had a whole Tablet applications group that did some really cool things with the tilt and pressure functions.
I have two 6 x 8 Wacoms with both pen and mouse tools. You can actually use both at the same time, but that doesn’t actually work on anything smaller than the 18 x 24.
Technology? They fuckin’ went in there with tanks and blasted through the windows and shot tear gas into the halls and smoke grenades that exploded and caused serious injuries, and they fired at unarmed civilians and…
It does indeed detect over a thousand pressure sensitive levels and detects the pen’s relative angle to the pad, making it a true artist’s perfect tool for the digital medium.
Anyone who is good at painting or drawing can take a Wacom and a copy of Painter and do amazing things with them.
“Good” paint programs will sense tilt and will adapt the shape of a spray (airbrush, spray paint, etc) “brush” - hold the pen straight up and you’ll get a round spray pattern. Tilt the pen, and the spray pattern stretches out so it’s heavy at the pen end and feathers out at the far end, just like a real spray would do.
The one that really amazes me is Wacom’s Cintiq device. The pressure- and angle-sensitive pen technology is transparent and laid atop an LCD tablet that the artist can lay on a desk or hold in their hand like a sketchbook while they work. The designer on TV’s American Chopper uses one extensively, and I’m envious.
One of my clients has one of the 21" Cintiqs as him main editing monitor - and a 30" and 20" on either side. It is an enviable setup, but was a bit of work to get all three working on his Power Mac.
I think it’s beneath the screen. I have an A4 sized Intuos2 at work and you can lift the pen a few centimetres above the surface and still control the cursor, so I imagine the signal will penetrate the thickness of a screen.
The reviews I’ve read for the Cintiq tablet bemoan the fact that it’s too bulky to comfortably hold in the hand and requires a desk to lean against. That might be an older model though.
It has a stand that allows you to tilt it up and rotate it. And the tablet is sitting on the movable part of a Anthro Fit bench, so it can be raised and lowered. I don’t have any photographs of his particular system, but it is very effective for him - he’s a professional photographer and does a huge amount of digital retouching on his images. Anything that makes his job easier or faster is going to be tried.
