Usinig IR laser as a TV remote

Hello guys,

I would like your help. I am not very experienced on the arduino and the electronics. So I want to turn on and off the TV via the arduino but with an IR laser module. I already did it with an IR led (KY-005) which was designed for the arduinoand it was easy. Now i want to do the same thing with an IR laser. My IR laser has only two wires black and red so i am struggling to connect it and also even if i connect it (which is wrong) it doesnt work with the previous code that worked before with the IR led. I was suggested to connect a buffer circuit to amplify the laser current which i made but i cant connect the three of them together (arduino, laser, buffer circuit). So i have a problem with the code and with the implementation also on how to connect all of them. Sosrry for any mistakes on my english.

IR LASER Datasheet --> https://www.egismos.com/laser-modules/IR-laser-module-D97805L.pdf

IR LED Datasheet --> KY-005, KY-005 Datasheet, KY-005 PDF - Joy-IT

Code that worked with the IR LED

#include <IRremote.h>
IRsend irsend;

void setup() {
Serial.begin(9600);
}
void loop() {

irsend.sendRC5(0x4C, 20); //Power Code
delay(7000);
}

Thank you in advance

Can we guess that you have noticed the vast difference in emitted wavelength between the two devices?
Paul

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You need an 808nm module. And getting it to read might be annoying because you'd have to hit the receiver dead-on.

I don't know about the code (use code tags btw), but I think a Google search would bring what you need.

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sorry I am inexperienced. I didn't know that..can you tell me more on what should i do ?

how did you get to this number about the nm ? thank you

I guess you need to study the data sheets and technical information on the devices before you purchase or include them in something you are designing. The wave length of the light emitter and the wave length of the light accepted is right there on what yo linked to.
And thank yo for the links in your first post. That is quite unusual!
Good luck, Paul

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The 808nm IR wavelength is industry standard for TV remotes. Get a laser around 800-850nm and it should still function.

Also, get something that's 1-5mW. Lasers are dangerous!

Even if you get the correct wavelength, a laser is not likely to work as well as an LED for IR remote control purposes.

The laser beam is very tight and there is much less scattered IR light, which is what the IR control receiver usually sees.

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Why the laser? Why not the usual LED?

Maybe they're doing something like I wanted to do.

I terminated that project BTW. Too expensive.

Why?

thank you very much

hmm thank you for your reply!

It's part of the tests i do for my thesis

because the arduino digital ports can't give enough current..i think it gives me less than 20mA..correct me if i am wrong..thanks for the reply

You said, " i cant connect the three of them together (arduino, laser, buffer circuit)". I asked why you can't. Are you asking how to connect them?

Wouldn't that be part of the expectations for the work that has to be done, to complete a thesis? Is the thesis in some subject area outside of electronics, like physics?

Yes, its part of my thesis I just dont know yet if i am gonna use it as it is now or i will change it..the title of my thesis is 'Pulsed laser tranceiver for telecommunications and remote control' thank you for your time

Just like to clarify some issues regarding the laser module for which the data sheet is linked in #1.

  • The wavelength of 780 nm is of course lower than standard remote controls use; with some luck it might be still detectable ... depending on the characteristics of the receiver diode.
  • However that module is not transmitting in a wide angle, it provides either (S-series) a laser bar OR (H9-series) a laser cross instead ... which means you have to "hit" the detector accurately. As you can read from the data sheet the line width is about 3.5 mm at 30 cm; if there was a linear divergence a rough calculation gives you a line width of about 7x3.5 = about 2.5 cm at 2 m -- tough to hit the detector. However it looks even worse: The divergence angle of the laser is stated as <1mrad. 1 mrad is equal to 1 m width at 1000 m ....

While LEDs usually provide let's say about 20°, laser diodes are generally producing highly parallel light which means you will still have about 3.5 mm laser width at 2 m or 10 m ... If you want a laser source to illuminate a wide angle you need optical means to shape (scatter) the beam.

In addition the laser mentioned is a cw laser (continuoes wave) which is also reflected in its low power of less than 5 mW. If you compare it with pulsed lasers these may achieve up to 100 or 200 W depending on the use. Still the cw laser may damage your (or other peoples or even animals) eye if not operated in a safe way. Especially because you cannot see infrared, it is even more dangerous than visible lasers. 780 nm is still a wavelength that the human eye can focus and that may burn your retina without any possibility to heal.

I would recon that the internal cw laser driver will not allow to modulate the laser with e.g. 38 kHz which you need for remote contrel communication.

So better step away from lasers and stay with IR LEDs. You do not need lasers for the usually short distances of remote controls, unless you want to cover several 100 m or even several kilometres.

You're welcome, but in fact you didn't answer any of my questions. So it was wasted time.

Similar:

https://forum.arduino.cc/t/solved-can-a-green-laser-pointer-be-modulated-to-38-khz/207821/12

https://laserpointerforums.com/threads/hello-vienna-is-calling-for-help-to-modulate-a-laser-on-38kz-carrirerfreq.103794/

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