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A refreshable braille display or braille terminal is an electro-mechanical device for displaying braille characters, usually by means of round-tipped pins raised through holes in a flat surface. Visually impaired computer users who cannot use a standard computer monitor can use it to read text output. Deafblind computer users may also use refreshable braille displays.
Speech synthesizers are also commonly used for the same task, and a blind user may switch between the two systems or use both at the same time depending on circumstances.
The base of a refreshable braille display often integrates a pure braille keyboard. Similar to the Perkins Brailler, the input is performed by two sets of four keys on each side, while output is via a refreshable braille display consisting of a row of electro-mechanical character cells, each of which can raise or lower a combination of eight round-tipped pins. Other variants exist that use a conventional QWERTY keyboard for input and braille pins for output, as well as input-only and output-only devices.
The mechanism which raises the dots uses the piezo effect of some crystals, whereby they expand when a voltage is applied to them. Such a crystal is connected to a lever, which in turn raises the dot. There has to be a crystal for each dot of the display (i.e., eight per character).
Because of the complexity of producing a reliable display that will cope with daily wear and tear, these displays are expensive. Usually, only 40 or 80 braille cells are displayed. Models with between 18 and 40 cells exist in some notetaker devices.
On some models the position of the cursor is represented by vibrating the dots, and some models have a switch associated with each cell to move the cursor to that cell directly.
The software gathers the content of the screen from the operating system, converts it into braille characters and sends it to the display.
Screen readers for graphical operating systems are especially complex, because graphical elements like windows or slidebars have to be interpreted and described in text form. Modern operating systems usually have an API to help screen readers obtain this information, such as UI Automation (UIA) for Microsoft Windows, VoiceOver for macOS and iOS, and AT-SPI for GNOME.
A rotating-wheel Braille display was developed in 2000 by the National Institute of Standards and Technology (NIST) and another at the Leuven University in Belgium. [1] In these units, braille dots are put on the edge of a spinning wheel, which allows the user to read continuously with a stationary finger while the wheel spins at a selected speed. The braille dots are set in a simple scanning-style fashion as the dots on the wheel spin past a stationary actuator that sets the braille characters. As a result, manufacturing complexity is greatly reduced and rotating-wheel braille displays, when in actual production, should be less expensive than traditional braille displays.
Assistive technology (AT) is a term for assistive, adaptive, and rehabilitative devices for people with disabilities and the elderly. Disabled people often have difficulty performing activities of daily living (ADLs) independently, or even with assistance. ADLs are self-care activities that include toileting, mobility (ambulation), eating, bathing, dressing, grooming, and personal device care. Assistive technology can ameliorate the effects of disabilities that limit the ability to perform ADLs. Assistive technology promotes greater independence by enabling people to perform tasks they were formerly unable to accomplish, or had great difficulty accomplishing, by providing enhancements to, or changing methods of interacting with, the technology needed to accomplish such tasks. For example, wheelchairs provide independent mobility for those who cannot walk, while assistive eating devices can enable people who cannot feed themselves to do so. Due to assistive technology, disabled people have an opportunity of a more positive and easygoing lifestyle, with an increase in "social participation", "security and control", and a greater chance to "reduce institutional costs without significantly increasing household expenses." In schools, assistive technology can be critical in allowing students with disabilities to access the general education curriculum. Students who experience challenges writing or keyboarding, for example, can use voice recognition software instead. Assistive technologies assist people who are recovering from strokes and people who have sustained injuries that affect their daily tasks.
Braille is a tactile writing system used by people who are visually impaired. It can be read either on embossed paper or by using refreshable braille displays that connect to computers and smartphone devices. Braille can be written using a slate and stylus, a braille writer, an electronic braille notetaker or with the use of a computer connected to a braille embosser.
A keyset or chorded keyboard is a computer input device that allows the user to enter characters or commands formed by pressing several keys together, like playing a "chord" on a piano. The large number of combinations available from a small number of keys allows text or commands to be entered with one hand, leaving the other hand free. A secondary advantage is that it can be built into a device that is too small to contain a normal-sized keyboard.
A pointing device is a human interface device that allows a user to input spatial data to a computer. CAD systems and graphical user interfaces (GUI) allow the user to control and provide data to the computer using physical gestures by moving a hand-held mouse or similar device across the surface of the physical desktop and activating switches on the mouse. Movements of the pointing device are echoed on the screen by movements of the pointer and other visual changes. Common gestures are point and click and drag and drop.
A dot matrix is a 2-dimensional patterned array, used to represent characters, symbols and images. Most types of modern technology use dot matrices for display of information, including mobile phones, televisions, and printers. The system is also used in textiles with sewing, knitting and weaving.
A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. The teletype was an example of an early-day hard-copy terminal and predated the use of a computer screen by decades. Starting in the mid-1970s with machines such as the Sphere 1, Sol-20, and Apple I, terminal circuitry began to be integrated into personal and workstation computer systems, with the computer handling character generation and outputting to a CRT display such as a computer monitor or, sometimes, a consumer TV.
A screen reader is a form of assistive technology (AT) that renders text and image content as speech or braille output. Screen readers are essential to people who are blind, and are useful to people who are visually impaired, illiterate, or have a learning disability. Screen readers are software applications that attempt to convey what people with normal eyesight see on a display to their users via non-visual means, like text-to-speech, sound icons, or a braille device. They do this by applying a wide variety of techniques that include, for example, interacting with dedicated accessibility APIs, using various operating system features, and employing hooking techniques.
Display may refer to:
A display device is an output device for presentation of information in visual or tactile form. When the input information that is supplied has an electrical signal the display is called an electronic display.
In computing, text-based user interfaces (TUI), is a retronym describing a type of user interface (UI) common as an early form of human–computer interaction, before the advent of bitmapped displays and modern conventional graphical user interfaces (GUIs). Like modern GUIs, they can use the entire screen area and may accept mouse and other inputs. They may also use color and often structure the display using box-drawing characters such as ┌ and ╣. The modern context of use is usually a terminal emulator.
The Perkins Brailler is a "braille typewriter" with a key corresponding to each of the six dots of the braille code, a space key, a backspace key, and a line space key. Like a manual typewriter, it has two side knobs to advance paper through the machine and a carriage return lever above the keys. The rollers that hold and advance the paper have grooves designed to avoid crushing the raised dots the brailler creates.
An output device is any piece of computer hardware that converts information or data into a human-perceptible form or, historically, into a physical machine-readable form for use with other non-computerized equipment. It can be text, graphics, tactile, audio, or video. Examples include monitors, printers, speakers, headphones, projectors, GPS devices, optical mark readers, and braille readers.
In human–computer interaction, a cursor is an indicator used to show the current position on a computer monitor or other display device that will respond to input.
Braille ASCII is a subset of the ASCII character set which uses 64 of the printable ASCII characters to represent all possible dot combinations in six-dot braille. It was developed around 1969 and, despite originally being known as North American Braille ASCII, it is now used internationally.
Braille technology is assistive technology which allows blind or visually impaired people to read, write, or manipulate braille electronically. This technology allows users to do common tasks such as writing, browsing the Internet, typing in Braille and printing in text, engaging in chat, downloading files and music, using electronic mail, burning music, and reading documents. It also allows blind or visually impaired students to complete all assignments in school as the rest of their sighted classmates and allows them to take courses online. It enables professionals to do their jobs and teachers to lecture using hardware and software applications. The advances in Braille technology are meaningful because blind people can access more texts, books, and libraries, and it also facilitates the printing of Braille texts.
Electrically operated display devices have developed from electromechanical systems for display of text, up to all-electronic devices capable of full-motion 3D color graphic displays. Electromagnetic devices, using a solenoid coil to control a visible flag or flap, were the earliest type, and were used for text displays such as stock market prices and arrival/departure display times. The cathode ray tube was the workhorse of text and video display technology for several decades until being displaced by plasma, liquid crystal (LCD), and solid-state devices such as thin-film transistors (TFTs), LEDs and OLEDs. With the advent of metal–oxide–semiconductor field-effect transistors (MOSFETs), integrated circuit (IC) chips, microprocessors, and microelectronic devices, many more individual picture elements ("pixels") could be incorporated into one display device, allowing graphic displays and video.
In computing, an input device is a piece of equipment used to provide data and control signals to an information processing system, such as a computer or information appliance. Examples of input devices include keyboards, computer mice, scanners, cameras, joysticks, and microphones.
The Linux console is a system console internal to the Linux kernel. A system console is the device which receives all kernel messages and warnings and which allows logins in single user mode. The Linux console provides a way for the kernel and other processes to send text output to the user, and to receive text input from the user. The user typically enters text with a computer keyboard and reads the output text on a computer monitor. The Linux kernel supports virtual consoles – consoles that are logically separate, but which access the same physical keyboard and display. The Linux console are implemented by the VT subsystem of the Linux kernel, and do not rely on any user space software. This is in contrast to a terminal emulator, which is a user space process that emulates a terminal, and is typically used in a graphical display environment.
A BrailleNote is a computer made by HumanWare for persons with visual impairments. It has either a braille keyboard or a Qwerty Keyboard, a speech synthesizer, and a 32- or 18-column refreshable Braille display, depending on model. The "VoiceNote" is the same device without a braille display. The BrailleNote GPS is an 18 or 32 cell BrailleNote with an External GPS module, BrailleNote GPS.
A braille e-book is a refreshable braille display using electroactive polymers or heated wax rather than mechanical pins to raise braille dots on a display. Though not inherently expensive, due to the small scale of production they have not been shown to be economical.