Tag Archive for: projected capacitive

I currently work in a warehouse where I come in contact with both Resistive and PCAP touch panels. I have heard that touch panels spread a lot of germs because they are used frequently and are not cleaned very often. I was just wondering, what would be the best solution to clean a touch panel? Can I use the same solution for both? Can I damage the screen by cleaning it or mess up the resolution? All I want is to be clean and germ free!

Dear Germaphobe,

First off, everything will be ok! Being exposed to germs can be a good thing for keeping your immune system strong and healthy. With that being said, there are a number of ways to go about cleaning and disinfecting touch panels with very minor, if any repercussions.

Resistive has one of the best reputations for durability and requires very little maintenance to keep in good shape. When building Resistive touch panels, they go through a series of processes, two of which consist of a hot hydrochloric acid bath, followed by a hot lye bath. If the screen is able to withstand opposite ends of the PH balance before it even gets into your hands then you must know it’s resilient.

PCAP is even more durable, thanks to the vast majority built with glass covers.GermaphobeCover glass has countless advantages including clearer resolutions and scratch resistance while matched with an incredible lifespan. Speaking from a chemical stand point, glass is virtually indestructible; there are very little chemicals that would harm the glass that wouldn’t harm a human. So, don’t worry as much about damaging the screen, we built them to be tough!

The most commonly used solution for Resistive and PCAP is just a simple isopropyl alcohol sprayed on a dry or soft cloth. Try to avoid using organic solvents and for dirt or residue use a neutral detergent or ethanol for clearing the touch panel.

A little known fact that might calm your nerves is every person has more germs on them and inside them than cells in the body. So go ahead and disinfect your workspace but don’t feel the need to constantly clean; it may do more harm than good!

Keep Calm and Touch On,
Touch Guy

“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

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