TouchGuy_Basic

Do you have a question for Touch Guy?

Send him an e-mail at asktouchguy@touchintl.com.

“Hey Touch Guy, why can’t the military use projected capacitive?” – Ready, aim, fire!

Whoa, simple question – complex answer.

First, the “military” does use projected capacitive (p-cap for short), and purchases a huge number of iPads and iPhones.  But I think your question is, “Can the military use p-cap in a battlefield environment.”  Yes, there are problems that have slowed the introduction of p-cap.  Here are a few that need to be addressed, and are being overcome.

Most of the armed forces are very careful about generating EMI that could be detected by the bad-guys.  P-cap, you will recall, works by having a human drain capacitance from the touch screen at the touch point.  For multi-touch, that means lots of small fields are created on the TouchGuy_Basicsurface of the touch screen.  The fields are quite small, and inconsequential compared to the EMI from radios that are in most devices, but they are still there.  TI has been able to tune the frequency to meet

EMI is a general problem, but it’s not alone in the obstacles p-cap must overcome.  The Navy and Coast Guard, not surprisingly, want rain and sea-water immunity.  Solutions have been developed in the electronics to compensate for tap and rain water.  But sea water, because it is more conductive, is a more difficult matter because it spreads a conductive film across the touch area, and when a finger is touched to the screen the capacitance is drained from lots of points which confused the touch electronics.  TI has developed a new total immunity sensor that works both mechanically and electrically to provide immunity to sea water.

Both the Army and Air Force require gloved finger operation.  For most flight applications, the gloves are thin-enough that p-cap is a great choice.  However, for some Army applications, the gloves are bigger and thicker and an accurate touch is more difficult…Touch Guy does not think this is a real issue because if the gloves are so big and bulky, how can you touch a small point anyway?

Impact, and the resulting breakage, is another issue, as most p-cap touch screens are made from glass.  There is also a weight issue in using glass.  The obvious solution is to make the p-cap sensor completely out of plastic or some form of acrylic substrate, however, plastic can scratch in some environments. Technology to the rescue, there are new transparent hard-coats for plastics that can approach the scratch resistance of glass.

In conclusion, Touch Guy believes the real roadblock preventing the introduction of p-cap into the battlefield isn’t the touch sensors themselves, but the lack of new programs that would make use of the latest and greatest touch technology has to offer.

Remember, I come in peace! – Touch Guy

All the display companies were showing off their cool new products at Display Week in Boston. In your opinion, what are the up-and-coming display trends, and what trends are currently in the market that you expect to decline?

Dear Steve,

At last, a question that is 100% opinion and therefore has the possibility of being 100% wrong. Overall, Touch Guy thinks there was nothing new at SID that would be of practical use to the average Joe or Josephine. There were lots of new ways to make the same things. In the past two years we have had 3-D displays (with and without glasses), LCD windows (see-through LCD’s, this time used to expose the contents of your refrigerator), and reflective color-LCD’s (your Kindle in Technicolor), which are still a’watin customers. This year is another year where the printable display (OLED) was a no-show. Twisty LCD’s made a comeback, and Apple commercialized an even prettier LCD (we need a Moore’s law for pixel resolution). Touch Guy thinks we should close the display division of the patent office and send all of the red-tape workers over to the social networking and internet security/warfare sections. (It is an urban myth that President McKinley tried close the patent office in 1899 because “everything had been invented”.)

For the last several years we display-professionals have been doing a good job of turning Gene Roddenberry’s Star-Trek fantasy into reality. The perception has been that the next big breakthrough will be the invention of the Holodeck. But the Holodeck seems like a long way off…Looking at the Holodeck concept TouchGuy_Basicrealistically, the power required to support video projectors and 1000 inch displays will likely be impractical. So instead, our concept will likely shift to tiny-3D displays in goggles with an awesome set of stereo ear-bud speakers (the Gen X gamers will like this better). Goggles do not actually you to move as you would in Roddenberry’s vision, and these tiny displays are a good reason to dust off the Gen 4 TFT LCD fabs that litter the Chinese landscape.

At the Future of Touch and Interactivity Conference, Geoff Walker gave compelling talk on why touch screen companies will continue to prosper (whew, Touch Guy can stop checking his social security statement) and Mark Finn continued to justify why we will be more interactive with our displays by waving body parts around in proscribed ways that he calls gestures.

Lest you think Touch Guy too cynical, there were a few note-worthy trends: 3M was showing a 360 degree privacy filter for those people trying to nonchalantly peek over the top of your laptop, read upside down, and steal your valuable data (Touch Guy has no valuable data not already shared with Google, so he will not be buying this). Nano-everything was in the air (here’s hoping those particles do not cause lung cancer (kidding), and there was micro-glass so thin that it could only be transported and processed with another piece of thicker glass. The Corning Gorilla (glass) has been joined by a Japanese Dragon and a German party called Xensational – more tough animals are rumored to be on the way… Check out Touch Guy’s white paper on toughened glass.

Good things to look forward to. Wake me up in 2014.

I am interested in creating a device with contains a multi-touch capacitive screen with many curves and bends. I am wondering if this is possible, and what the potential price range might be.

Dear Mr. Curve-A-Lot.

Needless to say, you have Touch Guy’s curiosity aroused as to what you would do with this curvy-bendy-multi-touch touch-screen. Also, he wants to make sure you need this to be transparent because that drives the touch sensing technology and ultimately the cost…..and do you need proximity sensing as well?

In the antediluvian days of CRT’s, all touch screens were curved, so we are familiar with building curved touch screens. Since then, plastic and glass forming has advanced to allow for just about any possible shape. Part of the magic is the use of transparent nano-inks to follow the contours of your crazy design and still remain conductive.

Though it is not the typical PCAP product, Touch International does build all-plastic projected capacitive touch screens for remote controls, automotive panels, and aerospace devices. The cost depends upon the materials, glass or plastic, and the tools needed form to your contour. Once the tooling is designed and proven, the cost to produce each part is not exceptionally high.

So yes, what you want to do is completely possible, but you are going to have a lot of fun interpreting the touch coordinates!

Touch Guy