When Brightness < ()
when brightness \< ()::ev3 hat
Category EV3
Type Hat
Introduced in 3.0
The correct title of this article is When Brightness < () (block). The Scratch Wiki uses this different title because of technical restrictions.
Document.png Please expand this article or section. You can help by adding more information if you are an editor. More information might be found in a section of the talk page. (March 2020)

The when brightness < () block is a Hat Block in the LEGO MINDSTORMS EV3 Extension. It starts its script when the EV3's detected light volume is less than the specified value.


This block can be replicated by the following code:

if <(brightness::ev3) < () > then
. . .


when green flag clicked
wait until <(brightness::ev3) < () >
. . .

Example Uses

  • Detect when the light is turned off in a room
  • Detect when the light sensor is covered by a solid object
  • Detect the overall brightness of a room

See also