detecting water drops using IR transmitter and tsop1738

i am doing a project to detect and count the number of drops dripping using a IR transmitter and IR receiver TSOP1738, i dunno how to interface these with arduino.........can someone please help me and provide the code???????

Does a water drop interrupt IR light?

larryd:
Does a water drop interrupt IR light?

i think it can, can you tell me the code if you know how to do it????

hemanth09_:
i think it can, can you tell me the code if you know how to do it????

If we gave you the "code", then it would be our project.

Paul

The TSOP1738 is the wrong chip to use, that is designed for sending data and is not suitable for a blocking application.
Just use an unmodulated LED and a photo diode with an op amp.

The water does not block the signal but deflects out of the way. Due to the shape of the drop you get a double pulse.

Grumpy_Mike:
The TSOP1738 is the wrong chip to use, that is designed for sending data and is not suitable for a blocking application.
Just use an unmodulated LED and a photo diode with an op amp.

The water does not block the signal but deflects out of the way. Due to the shape of the drop you get a double pulse.

so can I get the code and what components to use???

No one is going to give you the code, especially for an assignment. We help you get it right we do not do it for you.

The 'TSOP1738' is designed to detect bursts of 38kHz IR light.

You can easily detect 500us wide bursts of 38kHz i.e. T=0 38kHz, T=500us NO 38kHz, T=501us 38kHz etc.

If your water drop does stop/reflect IR light, the output from the TSOP1738 will stop for the time the drop is in the range of the TSOP1738.

You could look for a dropout of pulses from the TSOP1738 and count these events.

However, a cleaner method is as mentioned, a IR TX LED and a photo transistor.

The ‘TSOP1738’ is designed to detect bursts of 38kHz IR light.

Yes but it can not cope with continuous pulses after about 50 it then stops responding until it gets a rest. See the data sheet.

This is what I was thinking:

Maybe a 555 timer ‘missing pulse’ circuit connected to the TSOP1738 at the input and Arduino at the output.

Tin can and a microphone works for me...

Put a reflector a dozen mm in front of one of these and arrange that the drops fall between the sensor and the reflector.

...or have these set up across a small gap and arrange that the drops fall between.