Capacitive Touchscreen Accuracy Test

When people are choosing a capacitive touchscreen phone, screen size and resolution are probably their main concerns. But in fact, accuracy is also an important aspect that determines the performance of a screen display. To find out which touchscreen smartphone can most accurately interpret finger inputs, the MOTO Development Group (not related to Motorola has conducted a simple test between four popular devices on the market.

The involved handsets are the Apple iPhone, HTC DROID Eris, Motorola DROID and Google Nexus One. By opening a basic drawing application and slowly drawing diagonal lines across the screen of each phone with a fingertip, MOTO compared their sensitivity and accuracy, showing that not all capacitive screens are made the same.

The company divided the test into two parts. The first one used the corner of a finger to apply light pressure to mimic light flicking and quick tapping on a virtual keyboard. The other used a full finger to apply medium pressure, which is similar to finger-touch motions such as scrolling through a web page. Lines must be drawn slowly, since it is more difficult for a display to trace a slow-moving contact point than a fast one.

The screen with the cleanest and straightest lines is the most sensitive and accurate one, according to MOTO. A quality screen will be able to produce linear output no matter how slowly you go, how much pressure you apply, and which part of the finger pad you use.

Based on the findings, the company concluded that the iPhone display has the best overall results, creating the most linear tracking with the least amount of stair-stepping, although its edge performance is the weakest among all. The Nexus One and Droid Eris tied for second place as they both produced fairly linear tracks and performed well in the edge areas. The Motorola DROID, which came out last, is reported to demonstrate stair-stepped and wavy lines.

Of course, the results might have been affected by slight variations in the finger movement, and the outcome may differ if we use a touchscreen stylus instead. But the test does tell us that not all screens provide the same level of accuracy. So if you are going to buy a touchscreen device, you may need to try it out yourself before making your decision.

Tags: iPhone Accessories, Apple iPhone 3G S Accessories, HTC Droid Eris Accessories, Nexus One Accessories, Motorola DROID (A855) Accessories, Touch Stylus Pen, Stylus With Clip For Apple iPhone