Daktronics
ITS Dynamic Message Signs
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Viewing Distance

The maximum distance travelers can identify a message on a DMS is called legibility distance. There are no indications in the MUTCD of how bright the LEDs on a DMS should be, but Daktronics strongly recommends a display brightness of at least 9,200 cd/m². All DMS should have intensity adjustment to optimize legibility in all ambient light levels.

DMS viewing distance graphic

Recommended maximum viewing distances when using nominal 7x5 font.

Viewing Ranges & Speeds

Character Heights 6" 9" 12" 18"
Viewing Range - Max. 300'
91.44 m
450'
137.16 m
600'
182.88 m
1100'
335.28 m
Viewing Speed - Max. 15 / 25 mph
24.14 / 40.23 km/h
15 / 35 mph
24.14 / 56.32 km/h
15 / 45 mph
24.14 / 72.42 km/h
35 / 75 mph
24.14 / 120.70 km/h

Character Sizes

  • 6 inch character = 20 mm pixel spacing
  • 9 inch character = 34 mm pixel spacing
  • 12 inch character = 46 mm pixel spacing
  • 18 inch character = 66 mm pixel spacing

Visit the Character Heights page for more information.

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