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Help making laser trip wire with LED counter Answered

I have seen a few different laser trip wire instructables here, but they are usually for triggering a nerf device or other projectiles. I am interested in a laser trip wire that would count objects as the laser beam was broken, and display the count on an LED screen. I was wondering if someone would be kind enough to create an instructable for this. This has real world applications, such as counting cases moving along a conveyor line. I would like to use an arduino with a shield for this, and be able to plug it into an outlet. I am a complete Noob when it comes to arduinos. This is a project that I would like to get my feet wet with. I learn best by working on something that interest me. I know it isn't as much fun as a nerf Gatling gun, but it would get plenty of use every day.


Hey babycody! I know just the thing you are looking for. And it is much simpler than you had thought. Here is a site with scrupulous instructions on how to make a LASER people (or object) counter:

Hope it was useful!


7 years ago

No need for a shield, all you'd need is a phototransistor and a few resistors. An LCD screen could be used for the display. And, of course, an inexpensive laser pointer.

I'm working on something that could be adapted to this purpose, I hope to have it finished this month.

Had any luck with your project Jeff?

It's coming along, it needs a few software tweaks and a case.

Gee whiz, every time I get an idea LOL

Hi jeff-o. I would still love to see an instructable on this project. I check back weekly hoping to see it.

Looking forward to seeing your instructable on this Jeff