Source: Tom's Guide | Keywords: touchscreens | Themes: Display Panels and Monitors, Digital Entertainment, Business
4. Capacitive Screens
Projected capacitive screens are the second most widespread type of touchscreen used today. Their design differs strongly from that of resistive screens, though there are similarities. As with resistive screens, the technology is based on the use of a tactile layer deposited on the surface of the screen, but it works in a different way.
How Does It Work?
How a capacitive screen operates (source: Elo) Here, the glass surface of the screen is covered with a conductive deposit, generally indium tin oxide (ITO), which is transparent in very small thicknesses. This conductive layer is connected to electrodes deposited on the edges of the screen. In this way, a uniform electrical field is created at the surface of the screen, so the surface is uniformly charged. The approach of a finger disturbs the electrical field as a certain quantity of charge is transferred to the finger. This disturbance is what is detected by the control electronics. In early capacitive screens, the ITO layer was exposed on the exterior, so it eroded fairly quickly, limiting the product’s life. Today, detection algorithms have made enough progress for the ITO layer to be a certain distance from the pointer finger. This means that the screen surface can now be plain glass and wear is no longer a problem.
Still No Panacea The main advantage of capacitive screens is that they absorb a lot less of the display’s brightness. The thinness of the deposit guarantees good transparency (more than 90%). Also, they have excellent resolution, and the control module is very compact. But they remain significantly more expensive than resistive screens, and they’re sensitive only to conductive bodies. A bare finger is ideal, but a stylus or gloved finger won’t work. They’re also sensitive to the presence of water or humidity on the surface of the screen.
They’re Everywhere
The bottom line, though, is that the advantages of capacitive screens outweigh their disadvantages for many applications. Obviously, the first one that comes to mind is the Apple iPhone. In that particular application, in order to make the screen "multi-touch," Apple had to divide it into different zones, creating a grille of electrodes arranged under the screen. We might also mention that the trackpads or touchpads found on 99% of the laptops on the market use this technology (even though, strictly speaking, they’re obviously not screens).
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If they want to get a cheap way to integrate "Dual Touch" for a computer, just write a driver that allows them to use dual mice.
Most likely it wouldn't be that hard, and it would allow you to do many things that you can't with a single mouse.
That was a great article and it would be great to have a touch screen for PC's but only if you can use it with voice as well, This way you can get rid of the keyboard and mouse...unless they find a good way to use brainwaves but thats just a dream till probably 20 years or so I'm guessing.
All that has to be done then is to make something better than a mouse and keyboard for gaming because I don't see first person shooters working well with a touch screen.
Not quite interested in leaving my finger prints on my monitor. There was a thing called "IBM Light Pen" a long time ago, and guess where it is now? We don't even need two mice to do the same thing. Just program it so that hitting both left and right mouse button enables dynamic zoom with mouse going up and down.
The real next invention on human interface would be mind controller or FPS game controller that doesn't suck any more.