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An ultra violet LED and a photo transistor?

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I've got this Ultra violet LED and a  photo transistor.Please give me a circuit to make this transistor detect the ultra violet and do some function such as lighting another LED. 

9 Replies

rickharris (author)2013-01-06

It looks like your sensor is Infrared. Check the part number if it has one.

In general UV sensors tend to look like the attached photograph (google images)

To make things happen You need:

A resistor to control the current through the emitter!

A look at the data sheet for the sensor you have.

A typical IR sensor cct is attached from www.rapidonline.com

This feeds a on off signal to a microprocessor although with more effort you could use discreet electronics.

The other picture shows how to connect to a Picaxe microcontroller which as a specific command to read IR signals to do pretty much anything you like.


steveastrouk (author)2013-01-08

Get a photodiode instead.

I just bought an IR led and followed Rick's(suggested) schematics.All cool now.

Adarsh_tronix (author)2013-01-06

Tough luck!I've got the wrong components.But tell you what...I just flashed the uv led on the transistor and it was giving out some 0.040 volts through its base and emitter.I tried looking at the data sheet(1838 T) of the transistor and yes its an IR transistor.Thats an attractive circuit you've got there rickharris and I'll go with that one.Lyger000,I don't live in UK but India.I've never seen one of those things you just mentioned.Maybe if I dig deeper I'll find one or else could ship it from China.Thanks everyone!

Lyger000 (author)2013-01-06

In the UK the circuit you desire is mounted in the bottom of candles you can buy that glow different colours , the company called Glade makes the candles, the device in the bottom has threes leds red green and blue and the IR sensor which detects IR then lights the leds randomly. I use the device for checking the batteries in TV remotes etc. Hope it helps.

Adarsh_tronix (author)2013-01-06

Nope I've got a UV LED and a UV phototransistor.

well atleast thats what the shopkeeper gave me when I asked for one.

I got bad news for you then.

If its a UV LED, then you should be able to make washing powder glow in the dark.

And that transistor looks AWFULLY like a standard IR phototransistor.

steveastrouk (author)2013-01-06

You have an UV LED and an IR phototransistor ?