The back panel of a computer contains ports used to connect different peripherals that depend on the applications in use. Some of the devices that can plug into the ports include scanners, printers, cameras, speakers, microphones and game controllers, just to mention a few. VGA/DVI connectors are used to connect to other display devices while HDMI provides a connection to HD displays or TVs. The eSATA port is for connecting a computer to an external SATA hard drive. There is also an Ethernet port on a PC back panel that allows connections to the internet. Most computers have extra USB ports that are available at the back for instances when users need to use more devices.
Embedded systems are designed to handle specific purposes while regular personal computers(PCs) have several functions. For this reason, there are some physical differences between the two. One is that an embedded system has a small form factor, making it an ideal choice for an area with space constraints. An embedded system can perform its function without the need for an operator to physically access it, which means that they are easy to house, particularly in harsh settings. Another variation is that embedded computer systems don’t require hardware changes or additional storage.
Since before the introduction of the first capacitive touchscreen, exposure to water and moisture has posed problems for most electronics. That is until manufacturers started coming up with efficient waterproofing methods. Moisture and water causes damage to electronics and make operation of such devices in wet environments that much harder.
International Waterproofing Standards
Still, it would be wrong for companies to simply brand their products as waterproof. This is why there are international standards set for waterproofing. According to the International Electrotechnical Commission (IEC), devices that can be classified as waterproof must meet high Ingress Protection (IP) ratings. The highest achievable is IP-67 and such devices can be immersed in water up to 1m as well as handle exposure to dust.
Water Rejection and Wet Finger Tracking
There are primarily two subset definitions of waterproofing: water rejection and wet finger tracking. Water rejection is defined as the capacitive touch screen’s ability to reject false touches from occurring when liquid makes contact with the screen. At the same time, the screen should recover once the liquid has been removed.
Wet finger tracking, on the hand, refers to the touch screen’s capacity to track the position of a user’s finger even with the presence of water. It is well known that water on the screen affects the accuracy of touch when the screen is wet, and true waterproof screens will always maintain accuracy. The ideal number for tracking requirement in the presence of water is generally 1-2 mm.
Explaining Water Physics
Capacitive touch screen technology works through conductive touch. Because water is also conductive, this will make it more difficult for operation. To remedy this, waterproof touch screens make use of “self-cap” physics that allows the screen sensors to apply excitation signals to accurately sense the amount of charge it takes for the receiver.
The Basics of Waterproofing Capacitive Touchscreens, EE Times
Making Capacitive Touch Sensors Water Tolerant, Embedded