Choosing character height
The most important choice when you show text or numbers on an LED screen: how large should the characters be? It depends on the reading distance. We work in centimetres of character height. The rule of thumb: 1 cm of character height is comfortably readable up to about 5 metres. So 5 cm characters are readable up to ~25 metres, 10 cm up to ~50 metres. Always choose one size larger in bright ambient light or direct sunlight, at oblique viewing angles, or when the message is safety-critical (e.g. evacuation messages, production counters, warnings).
Character height versus reading distance
| Character height | Comfortably readable up to |
|---|---|
| 2,5 cm | ~12,5 m |
| 5 cm | ~25 m |
| 7,5 cm | ~37 m |
| 10 cm | ~50 m |
| 15 cm | ~75 m |
| 20 cm | ~100 m |
The values above assume a straight viewing angle in normal indoor light. In bright sunlight, at large viewing angles or for safety-critical applications, count on a shorter distance, or choose a larger character height. On an LED display you set the character height in the message software, so the same screen can show large alarm text that reads from far away and smaller detailed text up close.
We will soon add visual scale drawings (person, screen and reading distance) per model range to this page. Unsure about the right character height for your space? Send us the distance and viewing angle and we will advise the right setup.
Ask us for advice