OLR Exercises - Topic 7: Devices for Display and Interaction

Exercise 7.1: Smart Screen Interface Case Study

According to wikipedia (2009), “a touchscreen is a display that can detect the presence and location of a touch within the display area.” There are three basic types of touch screen: the resistive, the capacitive and the surface acoustic wave.


The resistive touch screen has several layers including two electrically conductive layers separated by spacers. When an object or finger presses the screen, the layers touch which changes the electrical current and registers with the operating system. Resistive systems are slower and admit less light than other systems, but they are cheaper. They can also be operated by objects such as pens or a stylus. Many PDAs and mobile phones use these screens.

Touch Systems. (2009).

The capacitive touch screen is a type of LCD screen with a layer that stores electrical charges within it. Because the human body is an electrical conductor, the screen responds by touching it with a finger without pressure. Touching the screen with a finger “disrupts the electronic capacitor's field, the finger's location is recorded and transmitted to the device's software controls” (Obsessable. 2009). These screens have better clarity and admit more light than the resistive screens, and only require a light touch with a finger. However they are more expensive than the resistive screens, and they do not respond if the user is wearing gloves or using an object such as a pen or stylus.

Touch Systems. (2009).

Surface acoustic wave (SAW) screens are the most advanced of the three touch screen systems. Reflectors and two transducers (one receiving and one transmitting) are placed on X and Y axis on the touch panel. The reflectors reflect electrical signals from one transducer to the other, converting the signal into ultrasonic waves when the screen is touched. When the screen is touched by a finger or object such as a stylus, the waves are absorbed and a touch event is detected at that point. The SAW screens use the most advanced technology, are more durable, have higher light transmission and better clarity than either the resistive or capacitive screens. SAW will work with a finger, gloved hand or a stylus.

Touch Systems. (2009).

Touch screens are used in many situations including mobile phones, PDA devices, ATM machines, Gaming Machines and Public Information Kiosks. The screens are easy to read and use and so are becoming more and more popular. Just yesterday I signed for an Australia Post delivery using a touch screen and stylus device which allows the company and it's customers to track parcels from door to door. Many classrooms now have interactive whiteboards allowing more collaboration and interaction between students, teachers and technology.


References:
Electrotest PTe LTD. (2004). Capacitive Touch Screens. Accessed on 1 October 2009. http://www.electrotest.com.sg/Capacitive_Touch_Screens.htm


Obsessable. (2009) Capacitive Touch Screen. Accessed on 1 October 2009 from http://www.obsessable.com/glossary/capacitive-touchscreen/

Touchsystems. (2009). Touch Screen Technology. Accessed on 1 October 2009. http://www.touchsystems.com/TouchScreen_Technology.php


TVI Electronics. (2004-2009). Touch Screen Technology. Accessed on 1 October 2009 from http://www.tvielectronics.com/Touch_Screen.html

Wikipedia (2009). Touchscreen. Accessed on 1 October 2009 from http://en.wikipedia.org/wiki/Touchscreen

Exercise 7.2 New devices, aged care and people with disabilities

“Assistive Computer Technology exists to help people with disabilities improve their lives and increase their independence and productivity” (Assistive Computer Technology. 2006-2008).There are many devices and software applications available to assist the elderly and people with disabilities. Some devices listed at the Ability Hub website include:

For visual impairments:
Screen Reader software reads aloud information displayed on a computer monitor

Screen Magnification software enlarges the viewing area of a computer monitor display

Optical Character Recognition systems use a flatbed scanner and software for inputting printed information into the computer to be read aloud and/or magnified

For deaf and hearing impairments:
iCommunicator is a system that allows two-way communication for people who are deaf, hard-of-hearing or experience unique communication challenges.The iCommunicator translates in real-time:
• Speech to Text
• Speech/Text to Video Sign-Language
• Speech/Text to Computer Generated Voice

Mobility Impairments
Environmental Control Units allow people with mobility impairments to control electronic appliances as: a television, radio, CD player, lights, and fan etc. This is accomplished using voice activation, switch access or a computer interface. Electronic wheelchair controllers can also be interfaced for accessing electronic appliances.

Hand impairments
Touch screen technology does not require the use of mice or keyboards, which may be difficult for people with hand impairments and arthritis.

It is possible to obtain mouse controllers that are able to be controlled by eye, head or feet movement.

Keyboards are available with larger keys, customised overlays and in Braille.


Bluetooth, WiFi and mobile technologies make computer assisted technologies more portable, flexible and accessible, just as it does for the rest of us!

References:

Ability Hub. (nd). Assistive Technology Solutions. Accessed 1 October 2009. http://www.abilityhub.com/index.html

Assistive Computer Technology. (2006-2008). Assistive Computer Technology Home Page. Accessed 1 October 2009. http://www.assistivecomputertechnology.com/

icommunicator. (nd). icommunicator Product Inofrmation. Accessed 1 October 2009. http://www.myicommunicator.com/