Using Photomultiplier Tubes with Arduino for Data Acquisition

Hi!

Is it feasible to connect photomultiplier tubes (PMTs) to an arduino uno board to sense fluorescence light intensity? I have previously worked with spectrometers but have been advised that PMTs are much more sensitive.

Also, as opposed to purchasing expensive data acquisition units to connect to the PMT, is it feasible to connect it with arduino boards instead? I have attached the specification of the PMT that I am currently looking at.

I understand that this PMT can be connected to a 5V powersupply and GND, but where can I connect the signal output to? Can I connect the signal output to one of the anolog pins inside the arduino board?

Cheers,
John

Without the model number, we have no idea. A link would help.

Weedpharma

Thanks for your reply!

Here's the link to the specific PMT that I am looking at. http://www.hamamatsu.com/jp/en/product/alpha/P/3003/3044/H10721-01/index.html

You can not connect the output directly to an Arduino and expect to see anything. With only 100uA maximum output you need a good stable amplifier.

I would expect that 100uA can drive an Arduino analog input with no amplification.

The issue here is that the output is given in terms of current, not voltage. Typical sensitivity is 400 amps per lumen. (You are obviously only going to be measuring nanolumens with this thing.) So there needs to be some analog circuitry to turn this current signal into a 0-5V voltage signal which the Arduino can read. An instrumentation amplifier should be fairly easy to wire up for this.

I found that they have another model that has a signal output in voltage instead. http://www.hamamatsu.com/eu/en/product/alpha/P/3003/3045/H10722-01/index.html

The voltage seems to be between 0-5V. Is this feasible?

Or would using a DAQ be a lot better than using an arduino?

A resistor is a good way of converting a current into a voltage.

However that new one looks fine for direct connection.

I think you would be better off using a comparator so you could use digital pins as the input as it would be much faster. Wiki has a good page on comparators if they are new to you. Basically a comparator is a device that puts out a fixed voltage whenever its input is higher than and threshold input. You set the threshold input, usually with a potentiometer, and the output is at a level that will trigger a high reading on a digital input.

The output of the PMT will be a current proportional to the light intensity, up to 100 microamperes maximum. To use this with the Arduino, you would need a current to voltage converter, with output range of 0-5 V.

That particular PMT module requires a 5V power supply plus a precisely controllable variable voltage source, in the range of 0.5 to 1.1 V, to control the internal high voltage generator. That control voltage source would have to be constructed or purchased.

PMTs are easily destroyed by exposing them to too much light (e.g. room lighting) while powered up.

Appreciate all the advise guys! I will look into a comparator as well as a control voltage source.

Also, thanks for the precautionary advise on exposing PMTs to direct light. I plan to house the PMT in a casing so hopefully it would not be very exposed.

It might help to add another light sensor, that shuts down the PMT when it detects too much light.

I found that they have another model that has a signal output in voltage instead. http://www.hamamatsu.com/eu/en/product/alpha/P/3003/3045/H10722-01/index.html

Sorry, I overlooked this post. This is perfect for the Arduino. What does the module cost?