H o w h e i p o d t o u c h w o r s H o w t h e i p o d t o u c h w o rk s By Daniela Prattico
The newest iPod design is the iPod touch. A display screen covers most of the front surface of the iPod touch, making it resemble an iPhone . But the iPod touch doesn't have a virtual Click Wheel that appears on the screen. Instead, it uses the same multi-touch interface that the iPhone uses
The iPod Touch Interface Wh en you touch the screen, the iPod's circuitry detects the presence of your finger. It keeps track of how many fingers you have on the screen and where you move them.
Self capacitance: Circuitry monitors changes in an array of electrodes.
Mutual capacitance: A layer of driving lines carries current. A separate layer of sensing lines detects changes in the electrical charge when you place your finger on the screen.
There are two possible methods the iPod touch can use to measure changes in electrical states.
Regardless of which method the screen uses, you change the electrical properties of the screen every time you touch it. The iPod records this change as data , and it uses mathematical algorithms to translate the data into an understanding of where your fingers are.
The iPod Touch Processor The iPod touch's processor keeps track of where you put your fingers and where they move once you've placed them on the screen. You can slide your fingers from place to place, or you can make pinching or spreading motions to zoom in and out. The iPod touch matches what your fingers are doing with what's happening on the screen:
The iPod touch determines the shape, size and location of your finger, or fingers on the screen.
The device uses gesture software in its memory to classify your touch. It takes into account whether your fingers move and what your iPod is doing at the time.
The processor sends instructions to the iPod touch's display, software and hardware based on the data your fingers create.
Figuring out your touch input requires the cooperation of the iPod touch's processor, operating system, hardware and software.
The iPod Touch Features It's easy to think of the iPod touch as a stripped-down version of the iPhone instead of a souped-up iPod. The iPod touch is a few centimeters smaller in length and depth, and it weighs about half an ounce (15 grams) less than the iPhone. The iPhone's battery also lasts a little longer than the one in the iPod touch. The iPhone has about 24 hours of audio or seven hours of video playback time, and the iPod touch can play 22 hours of audio or five hours of video on a full charge.
The two devices do have a few things in common ...
Flash memory (8 GB for the iPhone, 8 or 16 GB for the iPod touch)
WiFi capabilities (802.11b/g)
Safari Web browser
Audio, video and photo storage and playback
YouTube video player
Calendar and contacts that synch with your computer