I did a circuit diagram to measure distance, but this sensor can only measure 10 cm it should measure 60 cm. How can I do that? I used ne555 osilator with 40 kHz, tl084cn opamp, ir led (it must be ir led for my project) and photodiode. At the end of my circuit diagram, there is a peak detector.
Please help to improve my circuit or pls send me another circuit diagram.
Reloadron, I didn't draw the shematic on PCAD or else, I only did it on breadboard. I will draw and send tomorrow.
Vizier87, really it is a good idea, I should try it, thank you. could you please give me some information about your circuit? what kind of ir led, photodiode,op amp, timer...ect... did you use?
You want to measure distance or detect the presence of an object at 60cm?
If you want to measure the distance I would suggest ultrasonic as it is easier to measure the speed of sound rather than the speed of light at a short distance.
I'll make it easier for everyone. This is the OP's circuit: **broken link removed**
Hi Mehmed, I used a very simple comparator mode one. However, it is not pulsed. Here is the lousy circuit by me, just for your info.
(PS Guys, this is a lousy circuit, in case you guys're gonna take a poke at me )
which led is IR LED? there is another LED at the left part. and what kind of lens did you put in front of the IR LED, where can I buy it?
thank you.
Aleykum Selam.
Hi SneakSz,
the first schematic is not mine, I was just posting the circuit to make it easier for everyone to see, since it was given as an attachment.
I suppose C2,3,4 are filter and bypass capacitors to suppress certain frequencies so that the IR signal is given out in a nice range. The datasheet of an LM358 would explain more, I believe. But I'm not familiar with filters, FYI.