Product Code Database
A touchpad or trackpad is a type of pointing device. Its largest component is a tactile sensor: an electronic device with a flat surface that detects the position and motion of a user's fingers, and translates them into 2D motion to control a pointer in a graphical user interface. Touchpads are common on Laptop, contrasted with , with which Computer mouse are more prevalent. Trackpads are sometimes used with desktop setups where desk space is scarce. Wireless touchpads are also available, as detached accessories. Due to the ability of trackpads to be made small, they were additionally used on personal digital assistants (PDAs) and some portable media players.
Like touchscreen, touchpads sense absolute position but their resolution is limited by their size. For common use as a pointer device, the dragging motion of a finger is translated into a finer, relative motion of the cursor on the output to the display on the operating system, analogous to the handling of a mouse that is lifted and put back on a surface. Hardware buttons equivalent to a standard mouse's left and right buttons are sometimes positioned adjacent to the touchpad.
Some touchpads and associated device driver software may interpret tapping the pad as a mouse click, and a tap followed by a continuous pointing motion (a "click-and-a-half") can indicate dragging. Tactile touchpads allow for clicking and dragging by incorporating button functionality into the surface of the touchpad itself. To select, one presses down on the touchpad instead of a physical button. To drag, instead of performing the "click-and-a-half" technique, the user presses down while on the object, drags without releasing pressure, and lets go when done. Touchpad drivers can also allow the use of multiple fingers to emulate the other mouse buttons (commonly two-finger tapping for right click).
Touchpads are called clickpads if they rely on software buttons rather than physical buttons. Physically the whole clickpad formed a button, logically the driver interprets a click as a left or right button click depending on the placement of fingers.
Some touchpads have "hotspots", locations on the touchpad used for functionality beyond a mouse. For example, on certain touchpads, moving the finger along an edge of the touch pad will act as a scroll wheel, controlling the scrollbar and scrolling the window that has the focus, vertically or horizontally. Many touchpads use two-finger dragging for scrolling. Also, some touchpad drivers support tap zones, regions where a tap will execute a function, for example, pausing a media player or launching an application. All of these functions are implemented in the touchpad device driver software, and can be disabled.
By 1982, Apollo Computer desktop computers were equipped with a touchpad on the right side of the keyboard. Introduced a year later, in 1983, the first battery-powered clamshell laptop, the Gavilan SC included a touchpad, which was mounted above its keyboard, rather than below, which became the norm.
Psion's MC 200/400/600/WORD Series, introduced in 1989, came with a new mouse-replacing input device similar to a touchpad, although more closely resembling a graphics tablet, as the cursor was positioned by clicking on a specific point on the pad, instead of moving it in the direction of a stroke.
Laptops with touchpads were launched by Olivetti and Triumph-Adler in 1992. Cirque introduced the first widely available touchpad, branded as GlidePoint, in 1994. Apple introduced touchpads with modern placing in the PowerBook 500 series in 1994, using Cirque's GlidePoint technology,Thryft, Ann R. "More Than a Mouse," Computer Product Development, EBN Extra, November 14, 1994, pp. E16 – E20 which Apple refers to as a "trackpad"; it replaced the trackball of previous PowerBook models. Since 2008, Apple's revisions of the MacBook and MacBook Pro incorporated a "Tactile Touchpad" design with a button integrated into the tracking surface (the lower part of the touchpad surface acts as a clickable button).
Another early adopter of the GlidePoint pointing device was Sharp. Later, Synaptics introduced their touchpad into the marketplace, branded the TouchPad, and Epson was an early adopter of this product with their Epson ActionNote. As touchpads began to be introduced in laptops in the 1990s, there was often confusion as to what the product should be called. No consistent term was used, and references varied, such as: glidepoint, touch sensitive input device, touchpad, trackpad, and pointing device.
Users were often presented with the option to purchase a pointing stick, touchpad, or trackball. Combinations of the devices were common, though touchpads and trackballs were rarely included together. Since the early 2000s, touchpads have become the dominant laptop pointing device as most consumer laptops produced during this period and beyond includes only touchpads, displacing the pointing stick.
One-dimensional touchpads are the primary control interface for menu navigation on iPod Classic portable music players and additional input method on some Wacom digitizer tablets, where they are referred to as "click wheels", since they only sense motion along one axis, which is wrapped around like a wheel. Creative Labs also uses a touchpad for their Creative Zen line of MP3 players, beginning with the Zen Touch. The second-generation Microsoft Zune product line (the Zune 80/120 and Zune 4/8) uses touch for the Zune Pad.
Touchpads also exist for desktop computers as an external peripheral, albeit rarely seen. But touchpad layer can be integrated with graphics tablet as additional input option.
External computer keyboards can be equipped with integrated touchpads (particularly keyboards oriented for HTPC use), and some keyboards can have only touch input surface instead of hardware buttons (a typical solution for clean rooms).
primary can be used as part of ultraportable electronics; some handheld laptops and early smartphones can be equipped with optical trackpads.
On September 9, 2024, Apple unveiled the iPhone 16, iPhone 16 Plus, iPhone 16 Pro and iPhone 16 Pro Max to feature the single one-dimensional trackpad next to the side button called "Camera Control" which allows the users to take an easier way to take a photos and videos, the force sensor to distinguish between the firm press and the light press and the capacitance touch sensor to distinguish sliding with finger for adjusting the zoom, exposure or depth-of-field.
The capacitive shunt method, described in an application note by manufacturer Analog Devices, senses the change in capacitance between a transmitter and receiver that are on opposite sides of the sensor. The transmitter creates an electric field which oscillates at 200–300 kHz. If a ground point, such as the finger, is placed between the transmitter and receiver, some of the field lines are shunted away, decreasing the apparent capacitance.
Optical trackpad such as those found in some Blackberry smartphones work optically, like an optical computer mouse.
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