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increase IR LED transmitter range

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zr125

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how do i increase this IR LED transmitter range?

using additional circuit?

the details of the IR LED Transmitter are as follow :-

Feature:
Chip material:AIGaAs
Emitted color:infrared
Lens:5mm, water clear
Low power consumption, high efficiency, low current requirement
940nm wavelength
Forward current:50mA
Forward voltage: 1-1.7V
Radiant intensity: min 20mw/sr
Application: TV set, remonte controller, optical switches, optical encoders, smoke sensors ans so on.
Storage temperature: -20~ +85
Operating temperature: -20~ +75
Max. Forward Current: 100mA
Max. Forward Voltage: 1.7V
Max. Reverse Voltage: 5V
 

The light what it emits with given specs is final. You practically cannot increase IR emission beyond the LED limits. Only way is to use more LED's are use suitable optics like reflectors, or Lenses at the TX and RX or both which will converge/ concentrate the available light.
Cheers
 

i dont quite understand. can u explain a bit more?
 

practically you cannot increase the range of IR which is set to a maximum value as per the standards of manufacturing design...

IR comes in variety which gives you different length but you cannot trim or tune it beyond the distance mentioned in the data sheet..

You can use plastic enclosure on top of IR transmitter and restrict the transmission through a small hole instead of dispersing it in open air. So that we can concentrate the beams on on a IR receiver...
 

you can not increase the range of IR LED, you have to go with different manufacturer for wide range ..
 

so, how do i know the range for my IR tx, because the IR i bought, doesnt provide datasheet. :(

just the small info about the product on the 1st post.

---------- Post added at 14:08 ---------- Previous post was at 14:07 ----------

so, how do i know the range for my IR tx, because the IR i bought, doesnt provide datasheet. :(

just the small info about the product on the 1st post.
 

You don't say what range you are getting, what range you want, what optics you have, what the receiver is or what you are actually using it for. With so little information it is impossible to give a useful answer.

Keith
 

so, how do i know the range for my IR tx, because the IR i bought, doesnt provide datasheet. :(

just the small info about the product on the 1st post.
 

As pranam77 has said, for more range, which is more radiance, we must use more LEDs.
Here is a commercial IR radiator providing up to 18 Watts/sr.
**broken link removed**
It uses 480 LEDs to achieve its range and/or coverage.
 

just power ON the tx and rx.. connect a led and make it ON. when both tx and rx are close to each other (opposite to each other). Now make one as stationary and move the other away from the stationary tx.... check at what point the LED glows OFF...
Tune the pot so that the LED is ON again and then again try to move it further away.. do this till there is no effect of tuning the POT..

the point where the tuning of pot has no effect is the maximum distance you IR LED can operate.....
 

im getting about 2-3cm range (about 1-2inch)

i want to get bout half feet.

im using it for direction sensor, placing at door. to know either person go out/in.

it just a model. so i just use small box. a4 size box.
 

no. i did not use comparator.

im just using a simple circuit. 5v|-----vvvvv------>|------|gnd

vvvvv = resistor

>| = ir transmitter.

this is for transmitter.

for the receiver, its the same circuit. but with voltage divider. the output voltage of IR receiver will be fed to a PIC.
 

is it the transmitter or the receiver that give specific range?

im quite confused. is it my transmitter or the receiver that hv problem. :(

btw, im using PIC18F452, so do i need to use the comparator?

dont use sms kind of typing language in the forum
 
Last edited by a moderator:

yes you need to tune transmitter and receiver if you dont know the range of it..
as i have shown connect the receiver to the circuit and check what is the correct range of the IR pair and then connect it to controller.
 

no. i did not use comparator.
im just using a simple circuit. 5v|-----vvvvv------>|------|gnd
vvvvv = resistor
>| = ir transmitter.
this is for transmitter.
for the receiver, its the same circuit. but with voltage divider. the output voltage of IR receiver will be fed to a PIC.

so what value of resistor are you using ?

Most IR LED's should easily work over several metres without any difficulty

its a mix of both the type TX and RX diodes and how they are mounted that will determine the range
its about time you showed us all a proper circuit so we can see what you are doing and where you may have gone wrong

Dave
 

so what value of resistor are you using ?

Most IR LED's should easily work over several metres without any difficulty

its a mix of both the type TX and RX diodes and how they are mounted that will determine the range
its about time you showed us all a proper circuit so we can see what you are doing and where you may have gone wrong

Dave

220ohms. for both transmitter/receiver.

i'll post the proper circuit later. anyway,thanx!
 

Hi,

You havent described your application, so I'm going to give some generic advice.

I assume you need to transmit some kind of data, not just the presence / absence of light. In which case, *modulating* the IR signal will give you a manyfold increase in range. Use a modulation frequency of around 38 khz for best results. On the receiving side, you will now need a 3 pin IR demodulator to get back the original signal.

Once you have a modulation in place, even if your LED is rated for 50 mA, you can actually pump even upto 500 mA, provided your modulation duty cycle is low (10 to 20%), without damaging the LED. This will give you even more range, *at least 15 to 20 feet*.

A metal foil wrapped around the back of the transmitting LED like a funnel will act as a reflector to increase the range further.

Added bonus of this strategy is a solid reliable operation that is quite immune to ambient light conditions.

For any details or clarifications, please write back.

Regards,

Anand Dhuru
 

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