Light barrier

Discussion in 'English Only' started by kenjiro-san, Apr 5, 2013.

  1. kenjiro-san Member

    I'd like to ask you about an expression I found in the text about automatic road tolling system. Here's the sentence:
    "This solution is installed adjacent to the lane and requires no in-road equipment or light barriers."
    What do they mean by light barriers? Traditional traffic lights (ex. red, yellow, green) or something else?

    <<Second question deleted.>>

    Thanks a lot!
    Last edited by a moderator: Apr 5, 2013
  2. owlman5

    owlman5 Senior Member

    I wonder if your text is using "light barriers" to mean "barriers built of light material"? I can't tell from the context. It might also be using "light barriers" with the meaning "barriers with lights on them". I can't see any reason to believe that the text is referring to ordinary traffic lights.
  3. kenjiro-san Member

    That's exactly what I found confusing here. Light or light? :) But in this case I'd guess they mean traffic lights - perhaps not so ordinary, but ex. a red/off or red/flashing yellow system. Thanks anyway!
  4. Keith Bradford

    Keith Bradford Senior Member

    Brittany, NW France
    English (Midlands UK)
    I have come across the term "light barrier" to mean an infra-red or similar beam which hits a sensitive cell. When someone passes through the beam, a circuit is broken, triggering an alarm, or adding to a count, or halting dangerous machinery, etc.
  5. kenjiro-san Member

    Thanks, Keith, I guess this one fits best.

Share This Page