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Electronics => Electronics => Topic started by: zhangzongyang1990 on September 11, 2011, 01:58:00 AM

Title: Choosing Infrared Emitter Detector
Post by: zhangzongyang1990 on September 11, 2011, 01:58:00 AM
Hi,

I am trying to use infrared to do remote control. Basically I want to build a small model of room around 30cm x 30cm x 30cm and use a remote control to activate one of several electrical appliances in the room when I point the remote control to it.

So I need the infrared emitter to have narrow beam and the beam can reach 50 cm.

I know the beam width can be seen from the viewing angle. How can I tell what is the distance the beam can reach?

Now I have narrowed down the search result into 13 products. Please click the link below to see. Can anyone tell me which one is suitable for my project?

Thank you a lot!
Zy


Link :
http://sg.element14.com/jsp/search/browse.jsp?N=2108+202996+110064526+110145023+110186593+110177915&Ntk=gensearch&Ntt=infrared+emitter&Ntx=mode+matchallpartial&No=0&getResults=true&appliedparametrics=true&locale=en_SG&divisionLocale=en_SG&catalogId=&prevNValues=2108+202996+110064526&mm=1001507 (http://sg.element14.com/jsp/search/browse.jsp?N=2108+202996+110064526+110145023+110186593+110177915&Ntk=gensearch&Ntt=infrared+emitter&Ntx=mode+matchallpartial&No=0&getResults=true&appliedparametrics=true&locale=en_SG&divisionLocale=en_SG&catalogId=&prevNValues=2108+202996+110064526&mm=1001507)||,1002356||,&filtersHidden=false&appliedHidden=false&originalQueryURL=%2Fjsp%2Fsearch%2Fbrowse.jsp%3FN%3D2108%2B202996%26Ntk%3Dgensearch%26Ntt%3Dinfrared%2Bemitter%26Ntx%3Dmode%2Bmatchallpartial%26No%3D0%26getResults%3Dtrue%26appliedparametrics%3Dtrue%26locale%3Den_SG%26divisionLocale%3Den_SG%26catalogId%3D%26prevNValues%3D2108%2B202996
Title: Re: Choosing Infrared Emitter Detector
Post by: waltr on September 11, 2011, 09:16:59 AM
Quote
How can I tell what is the distance the beam can reach?

That depends on the optic power in the beam and the sensitivity of the detector and the Signal to Noise ratio.

A TV remote/detector will normally work to distances of several meters with ease. Google TV remote to learn how these work. Hint: the LED is modulated at around 38kHz and the detector has a narrow band demodulator to help reject ambient light thus giving a high SNR.
Title: Re: Choosing Infrared Emitter Detector
Post by: zhangzongyang1990 on September 12, 2011, 08:06:12 AM
Quote
How can I tell what is the distance the beam can reach?

That depends on the optic power in the beam and the sensitivity of the detector and the Signal to Noise ratio.

A TV remote/detector will normally work to distances of several meters with ease. Google TV remote to learn how these work. Hint: the LED is modulated at around 38kHz and the detector has a narrow band demodulator to help reject ambient light thus giving a high SNR.

I need to clarify that, the only thing I need the remote control to do is let MCU knows which device I am pointing to. After that all controls to the devices is given to MCU directly by the romote control.
So do I still need to do the modulation-demodulation? Can I expect something as simple as the one in this tutorial:http://www.societyofrobots.com/schematics_infraredemitdet.shtml   Only the transimission range is longer?

Thank you!
Title: Re: Choosing Infrared Emitter Detector
Post by: waltr on September 12, 2011, 06:16:27 PM
Maybe that simple circuit will work. The biggest problem will be if the room is brightly light. Then the detector may sensor that it is receiving the IR LED signal.

You're best bet is to wire up the circuit and test it. Then you'll not only know if it'll work for you but you will learn something is the process.
Title: Re: Choosing Infrared Emitter Detector
Post by: angad on September 12, 2011, 11:02:13 PM
Hi,

I am trying to use infrared to do remote control. Basically I want to build a small model of room around 30cm x 30cm x 30cm and use a remote control to activate one of several electrical appliances in the room when I point the remote control to it.

So I need the infrared emitter to have narrow beam and the beam can reach 50 cm.

I know the beam width can be seen from the viewing angle. How can I tell what is the distance the beam can reach?

Now I have narrowed down the search result into 13 products. Please click the link below to see. Can anyone tell me which one is suitable for my project?

Thank you a lot!
Zy


Link :
http://sg.element14.com/jsp/search/browse.jsp?N=2108+202996+110064526+110145023+110186593+110177915&Ntk=gensearch&Ntt=infrared+emitter&Ntx=mode+matchallpartial&No=0&getResults=true&appliedparametrics=true&locale=en_SG&divisionLocale=en_SG&catalogId=&prevNValues=2108+202996+110064526&mm=1001507 (http://sg.element14.com/jsp/search/browse.jsp?N=2108+202996+110064526+110145023+110186593+110177915&Ntk=gensearch&Ntt=infrared+emitter&Ntx=mode+matchallpartial&No=0&getResults=true&appliedparametrics=true&locale=en_SG&divisionLocale=en_SG&catalogId=&prevNValues=2108+202996+110064526&mm=1001507)||,1002356||,&filtersHidden=false&appliedHidden=false&originalQueryURL=%2Fjsp%2Fsearch%2Fbrowse.jsp%3FN%3D2108%2B202996%26Ntk%3Dgensearch%26Ntt%3Dinfrared%2Bemitter%26Ntx%3Dmode%2Bmatchallpartial%26No%3D0%26getResults%3Dtrue%26appliedparametrics%3Dtrue%26locale%3Den_SG%26divisionLocale%3Den_SG%26catalogId%3D%26prevNValues%3D2108%2B202996

  hi
i am inteterested in same plz give me ckt and required details. waiting for reply.
Title: Re: Choosing Infrared Emitter Detector
Post by: zhangzongyang1990 on September 13, 2011, 01:37:32 AM
Maybe that simple circuit will work. The biggest problem will be if the room is brightly light. Then the detector may sensor that it is receiving the IR LED signal.

You're best bet is to wire up the circuit and test it. Then you'll not only know if it'll work for you but you will learn something is the process.

Thx a lot! Could you help me choose one IR emitter&sensor that will most probably work from the link in the post above?