What is a braille display?

A braille display, also called a refreshable braille display, is an assistive technology device that converts on-screen text into physical braille characters. Round-tipped pins rise and fall in braille cells to form each letter, letting blind and low-vision computer users read digital content by touch rather than relying on screen reader speech alone.

At a glance

How do braille displays help improve accessibility?

Speech is not the only way blind and visually impaired computer users access digital content, and for many people with visual impairments, speech alone is not enough.

A screen reader has to guess at pronunciation, and it can skip over exact spelling and capitalization, along with punctuation, that a braille display shows precisely as written. That precision is most impactful during proofreading and word processing, but it can also assist people writing code, where hearing "comma" read aloud is a poor substitute for seeing the mark itself.

For deafblind computer users, a braille display serves as the primary way to access a screen, as audio output isn't an option.

Braille literacy also supports broader reading and writing skills. Research has found a positive relationship between braille reading fluency and spelling, while greater reliance on auditory aids such as speech output was associated with weaker braille fluency and spelling.

How does a braille display work?

A braille display connects to a computer, tablet, or other mobile device over USB or Bluetooth, then works alongside screen-reading software such as the JAWS screen reader, NVDA, or VoiceOver.

Some devices are output-only, while others support braille input for typing as well as reading. The screen reader reads the accessibility tree – a structured representation of the page that browsers build specifically for assistive technologies – and sends the currently focused text to the display instead of, or in addition to, speech output.

Each braille cell forms a character using tiny pins, often eight per cell on computer braille displays: the standard six-dot braille pattern plus two extra dots, used for marking capital letters and showing where the cursor sits, among other uses.

Users can set different combinations of dots 7 and 8, or turn the cursor indicator off entirely, depending on how they want the cursor position shown. A common mechanism uses piezoelectric crystals that expand slightly when voltage is applied, and that motion raises or lowers each pin.

On most displays, cursor routing buttons sit above each cell. Pressing one moves the text cursor or screen reader focus directly to that character, which is faster than arrowing through a sentence by ear to find one word.

Screen readers also offer braille key commands that emulate keyboard commands such as Alt+Tab, so a user can switch between open programs using only the keys on the display.

There are three main types of braille devices: stand-alone braille displays that only render output from a connected device, notetakers with their own storage and apps, and smart displays that sit in between – displays with a handful of built-in tools but no full app suite.

Most stand-alone displays include a Perkins-style keyboard for braille entry, though some support a standard QWERTY layout, and they range from compact 14-cell portable models to 80-cell desktop units.

Manufacturers making stand-alone displays include Freedom Scientific, HumanWare, Help Tech, and others, along with the American Printing House for the Blind, whose APH Orbit Reader is a widely used, lower-cost option. Most connect to Windows PCs, Apple computers, tablets, and smartphones over USB or Bluetooth, and some pair with multiple devices at once.

Braille display example

Braille access to a page depends on the underlying markup, not just the connected device. For a connected device to render meaningful braille while browsing websites, the underlying HTML needs an accessible name.

For example, a checkout button built with an icon and no text alternative:

<button><svg><!-- cart icon --></svg></button>

On a braille display, this reads only as an unnamed button (often abbreviated to something like btn), giving no clue what pressing it does. Adding an accessible name fixes that:

<button aria-label="Complete purchase"><svg><!-- cart icon --></svg></button>

Now the same button appears on the display as Complete purchase, plus the button role, giving braille users the same context a sighted user gets from the cart icon alone.

Braille display vs. screen reader

A screen reader reads and structures on-screen content. A braille display is the hardware that renders that same content as tactile braille. Most users pair the two, running a screen reader such as JAWS, NVDA, or VoiceOver, and switching on braille output only once a display is connected.

Common mistakes or misconceptions

• Assuming a braille display works without a screen reader. It needs one, or similar software on a notetaker, to supply the text in the first place.
• Assuming more braille cells is always better. Line length matters, but so does portability, and many users prefer a smaller, lighter display they can carry daily.
• Assuming a page that sounds fine with a screen reader also reads fine on a display. Vague link text like "click here" or unlabeled icons show up as meaningless placeholders in braille even when spoken output is passable.