I seem to remember seeing some material which fluoresces in IR light for testing remote controls. I can't find any such thing - did I imagine it?

 

Hello there
Remember radio shack used to carry them .I found this one, same difference

 

Yeah! 'Card' is the magic word.
https://www.ebay.co.uk/itm/115251665252?hash=item1ad588d964:g:x-sAAOSwcB5gbsTF

 

Got a camera? Got a cell phone with a camera? Got a webcam? They pretty much all are sensitive in the IR range.

Here's a picture I just took of the business end of a basic IR controller.

 

My phone camera doesn't 'see' IR. I seem to remember that they have a filter to remove IR.
For instance: https://www.quora.com/Why-do-manufacturers-put-IR-filters-in-smartphone-cameras

 

Hi Albert.
Does your laptop camera 'see' IR.?
E
Just checked mine sees it OK.

 

My phone camera doesn't 'see' IR. I seem to remember that they have a filter to remove IR.
For instance: https://www.quora.com/Why-do-manufacturers-put-IR-filters-in-smartphone-cameras

Every mobile phone and laptop camera has an IR bandstop filter. It’s needed because the sensors have response in the IR and it would swamp the visible light. The difference in sensors and filters, though, means that some can see still see IR very well, some less well, and some almost not at all to the point the visible light in the image renders it invisible.

It is possible that in a dark room you would see it.

 

My phone camera doesn't 'see' IR. I seem to remember that they have a filter to remove IR.
For instance: https://www.quora.com/Why-do-manufacturers-put-IR-filters-in-smartphone-cameras

Have you actually done the experiment, or just going by what someone on teh innerwebs said?

Admittedly my actual experimental evidentiary photo taken yesterday is a best case scenario where the camera is direct on the IR source. If I was just looking for a proof of life from an IR emitter this would be a fine test for zero dollars using equipment I (and many others) already possesses.

 

Have you actually done the experiment, or just going by what someone on teh innerwebs said?

Admittedly my actual experimental evidentiary photo taken yesterday is a best case scenario where the camera is direct on the IR source. If I was just looking for a proof of life from an IR emitter this would be a fine test for zero dollars using equipment I (and many others) already possesses.

This photo was taken with an iPhone 12 Pro Max. The red arrow points at the IR emitter of a Fluke Bluetooth transceiver. The green arrow points as a diagnostic LED on the circuit board that indicates an IR transmission. I can see nothing at all from the emitter.

The iPhone 12 Pro is supposed to have state of the art cameras. I imagine they made sure the IR cut filters were the best they could manage to maximize dynamic range. But, the webcam on my iMac also doesn't see it which leads me to believe the current IR cut filters have generally been improved.

An IR remote tester shows there is IR being produced. I do know that in the past, the IR emitters in remotes were readily visible on phone cameras but I had noted a reduction in sensitivity over time when I used it to check a remote. I guess my current phone is useless for the purpose.

​

 

Have you actually done the experiment, or just going by what someone on teh innerwebs said?

I did the experiment and saw nothing - about three inches from the LED.

 

Look for older cameras and iPhones.
I have a Canon and Sony camera and an old iPhone that I keep handy for exactly this purpose.

 

I did the experiment and saw nothing - about three inches from the LED.

Hi A,
Stating the obvious, are you convinced that the IR Emitter is actually emitting IR.?

E

 

Hi A,
Stating the obvious, are you convinced that the IR Emitter is actually emitting IR.?

E

Yes, an IR receiver sees the signal.

 

@AlbertHall in case it is useful, this component tester includes an IR remote decoder for some reason. It knows the common codes and can identify them. Even if it can't decode, it shows activity.

It is also a very good component test which has a lot of utility in its own right.

​

 

My interest is to be able to track where the IR is going - where the maximum intensity is - for an LED mounted in an enclosure. An IR card would make this easy.

 

My interest is to be able to track where the IR is going - where the maximum intensity is - for an LED mounted in an enclosure. An IR card would make this easy.

i don’t quite understand. Do you mean there is a IR LED mounted in an enclosure pointing to the outside or to the inside?

 

Pointing outside through a hole. I would need to make sure the LED and the hole are optimally aligned.
This is my design/build.

 

Pointing outside through a hole. I would need to make sure the LED and the hole are optimally aligned.
This is my design/build.

I have used a method in the past where I found a visible light diode (something like blue is good, white less so) that had the same size and optical characteristics then darkened the room and took a photo from the LEDs point of view.

The blue light shows up pretty well, with distinctive beam pattern, if you get the exposure right. It worked in my case where I was trying to avoid overlapping a couple of IR repeaters but I don’t know if it is useful for you.

 

You can pop (OK, crack) the IR filter off a digicam or webcam. I've done that successfully with a 640x480 webcam, haven't dared to do that to a better webcam yet, but it might be cool for watching critters in the back yard. Discussion of webcams, with the tip that a piece of exposed colour film negative works as an IR pass filter:
https://www.alcs.ch/logitech-c910-infrared-conversion-for-nightvision.html

Sony infamously made some camcorders where the "Night Shot" switch positioned half-way would remove the IR filter without fully enabling night mode, and therefore allowed voyeurs to see through clothing (more so if an external IR pass filter is used). There were other cameras where a magnet applied to the lens housing would disable the IR filter.
http://www.aparchive.com/metadata/youtube/ad99e1a3930185817a1275d284408e3b