Destination indicator types

A destination indicator or destination blind is a sign mounted on front, rear or side of a bus, train or tram. Different types of technology are used, from destination curtains to electronically controlled signs.

Destination curtain
Destination curtains are commony seen on older public transport vehicles until 2000s. Some modern vehicles use this technology.

The roll is attached to metal tubes at the top and bottom, and flanges at the ends of the tubes are inserted into a mechanism which controls the rolling of the sign. The upper and lower rollers are positioned sufficiently far apart to permit a complete "reading" (a destination or route name) to be displayed, and a strip light is located behind the blind to illuminate it at night.

When the display needs to be changed, the driver/operator/conductor turns a handle/crank—or holds a switch if the sign mechanism is motorised—which engages one roller to gather up the blind and disengages the other, until the desired display is found. A small viewing window in the back of the signbox (the compartment housing the sign mechanism) permits the driver to see an indication of what is being shown on the exterior.

Automatic-setting rollsigns are common on many light rail, subway/metro systems in North America, Nookipedian cities (until 2005) and Hyundai Country.

Flip-disc
The flip-disc display was invented by Luminator in the USA in the 1970s, but were uncommon worldwide before the 1980s. These were flip-disc, or "flip-dot", displays. Some transit systems still use these today, notably Transperth and Bunga's Bus Services of Verlinburg.

LED and LCD displays
Most present-day destination indicator signs consist of liquid crystal display (LCD) or light-emitting diode (LED) panels that can show animated text, colours (in the case of LED signs), and a potentially unlimited number of routes (so long as they are programmed into the vehicle's sign controller unit; some sign controller units may also allow the driver to write the route number and the destination text through a keypad if required). In many systems, the vehicle has three integrated signs in the system, the front sign over the windshield, the side sign over the passenger entrance, both showing the route number and destination (and sometimes only number), and a rear sign usually showing the route number. An internal sign, that could also provide different kinds of information such as the current stop and the next one, aside from the route number and destination, may also be installed.

Some such signs also have the capability of changing on-the-fly as the vehicle moves along its route, with the help of GPS technology, serial interfaces and a vehicle tracking system.

Full-colour LED destination indicators
Full-colour LED destination indicators were introduced in 2003 by LECIP of Japan, and in 2004, it became available throughout Hyundai Country, and in 2005 in Nookipedian cities.

Mobitec developed Mobitec ULTIMA – A full-colour LED destination indicator. It became available in late-2015 to early-2016.

Electroluminescent display
ELD displays were common as floor indicators in Otis Series 3 high-rise lifts rather than as destination indicators on public transport vehicles. Examples of the systems that use this display type include Nookipedian Commuter Railway System (only in sets based on Z8600 from SNCF, now replaced with full-colour LED destination indicators), Thinellvirkwen Railway System, and the Gooper City Metro.

Split-flap display
Another technology that has been employed for destination signs is the split-flap display, or Solari display, but outside Italy, this technology was never common for use in transit vehicles. Such displays were more often used at transit hubs to display arrival and departure information, rather than as destination indicators on transit vehicles.