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Infrared sensor distance

Hi, I'm doing my final proyect and I'm having problems figuring out the infrared emitter. The problem is that the sensor has to have 10 meters range sensitivity. So the beam has to reach the object and come back. That's 20 meters. I'm doing the oscilation with a 555 in astable mode, to provide me 10KHz to 40Khz.

I've already tried the circuit with a IR Led I had, but the range is less than 10 meters.

Any clues about what can I do?

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You might consider a different method such as sound. Here is some info on IR distance sensors: http://www.acroname.com/robotics/info/articles/sharp/sharp.html

If you're suppying the normal operating current to the LEDs you might try cranking it up and keeping the pulses short to prevent burnout. Chuckcrunch had posted a nice link about DIY IR distance sensors but I don't have it here at work.


that's some of the stuff have a poke around this site for other ideas

:thumbs up:

What is the current rating of the IR LED you are using? Can you increase the current safely to improve range?

10 meters are tough. I can see a big chance to get your singal scrambled.

However, increasing the power of the emitter could lead to a better signal but you still get the noice of all surounding heat sources. This could be avoided by coding the signal that the receiver just act when a specified code (e. g. morse code) is received.

What you want to achieve? Maybe with the purpose of your measuring we can help to find a alternative solution.

you can get more powerful ir leds on ebay.


The circuit is for an animal repeller. Once the animal gets into a ten meter range, the detection (IR) circuit should activate the rest of the circuit.

Can you set up a perimeter with pairs of IR detector/receiver beams, which indicate presence of an intruding animal when the beam is interrupted?