Identify this component


There’s a component in an arduino starter kit I bought that wasn’t labelled, so I don’t know what it is, hope someone can identify it for me.

It has 4 pins, one small led and another smaller but a darker (black) looking led or something. The two led’s are enclosed in a small black box (except from the top and bottom)

I’ve attached a few pictures of the component, sorry for the picture’s low quality

You’re joking, right?
2MB of fuzziness?

yeah, its a problem the lens


It is way too big even if it were in focus.

Is is sharp if you go further away? If so then crop the image to no more than 1000 pixels wide.

I’m guessing a reflective sensor: one side an LED, the other a phototransistor. Two pins would be LED’s cathode and anode, other two would be phototransistor’s collector and emitter (base being the incoming light).


Thanks I think you’re right, I googled reflective sensor and yeah thats the one

Do you think I can use this as a transistor?

Do you think I can use this as a transistor?


Do you think I can use this as a transistor?

It is indeed a reflective sensor.
Given that, what do you mean by “use this as a transistor”? Specify what you propose to use it for.

As to photography of such objects, a few hints; take it out in the sun to take a picture as this will minimise the aperture on your lens and improve the focus in all circumstances. You have a quite high resolution camera, so set it to maximum zoom, move at least a metre away from the object and take the picture - there is absolutely no need to have it fill a significant part of the picture. Use an editor - IrfanView on Wnidoze, or the utilities in Linux to crop out the object into a resolution more like 640 by 480 or (in this case), half or a quarter of the dimension.