|Resistive technology – Also called “Accutouch” by Elo.
Resistive technology is one of the most commonly-found types. Resistive screens consist of a plastic sheet laid over the glass of the screen. The plastic has electrical sensors embedded. When a user touches the screen their finger interrupts the electricity between sensors, activating the screen and moving the mouse to the point of the interruption. Since the technology is pressure-sensitive, a user can touch the screen with any finger or any relatively narrow object, such as a stylus. It is typically recommended for use in relatively environments where there are minor contaminants, such as the grease of a restaurant or the dust of a warehouse, as most of these contaminants do not directly affect touch functions.
|SAW (Surface Acoustic Wave) technology – Also called “Intellitouch” by Elo.
SAW technology consists of extremely high-pitched sound waves emitted from sensors around the edge of the glass on a monitor. When a user touches the screen they interrupt those sound waves, causing a new pattern in the waves and allowing the controller to determine where the screen was touched. A user must touch the screen with a finger or special stylus, as there are only certain wave patterns that the sensors recognize. Any droplet of water or significant dirt build-up will interfere with touch functions, so this technology is best used in clean, relatively quiet environments such as retail stores or offices.
Optical touch uses multiple optical sensors at the corners of the screen to determine a touch point. This technology will work with virtually any input device including finger, stylus, gloved hand. Optical is scalable and size & application which works well with healthcare, retail, and interactive digital signage applications. This technology provides a very clear image since there is no overlay on the touchscreen surface.
There are several types of capacitive technology available, usually called “Projected Capacitive” or “Surface Capacitive.” These work by using the electrical resistance of your finger to interrupt a grid of sensors embedded into the glass of the screen. Capacitive screens are most commonly found on smartphones, iPods/iPads, and smaller touchscreen devices.