Pages: [1]   Go Down
Author Topic: Increasing Infrared Reception Angle  (Read 769 times)
0 Members and 1 Guest are viewing this topic.
NYC
Offline Offline
Full Member
***
Karma: 0
Posts: 125
The singularity is near!
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

I made an Infrared transmitter and receiver, but it seems to only work when shooting directly on. It uses TSAL7600 Infrared Led and a TSOP2438 38 MHz Infrared Receiver.

Any ideas to allow it to work better from multiple angles? Anyone add a lens?
Logged

Manchester (England England)
Offline Offline
Brattain Member
*****
Karma: 508
Posts: 31431
Solder is electric glue
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

What power are you putting out from your diode? You could try reducing the resistor and driving it harder.
On the receiver supply decoupling close to the chip is very important for this device. Have you followed the arrangements shown in the application circuit on page 1 of the data sheet. If not that will reduce the sensitivity.
Finally as you made the transmitter is the pulse rate right for the device. You should get at least an 6ft range over 45 degrees with this.

To make it omni directional take a piece of perspex and drill a hole half way through it. Mount the received pointing into this hole and mount the whole thing at horizontally.
Logged

UK
Offline Offline
Faraday Member
**
Karma: 16
Posts: 2883
Gorm deficient
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Quote
38 MHz

You sure about that?
Logged

Per Arduino ad Astra

Manchester (England England)
Offline Offline
Brattain Member
*****
Karma: 508
Posts: 31431
Solder is electric glue
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

Quote
You sure about that?

yep - give or take three orders of magnitude.  smiley-wink
« Last Edit: June 04, 2010, 04:57:50 am by Grumpy_Mike » Logged

NYC
Offline Offline
Full Member
***
Karma: 0
Posts: 125
The singularity is near!
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

"To make it omni directional take a piece of perspex and drill a hole half way through it. Mount the received pointing into this hole and mount the whole thing at horizontally. "

I assume perspex is English for acrylic or plexiglass. Does it matter the shape of the perspex, like would a 1" circle with the led mounted in the center work? I guess this is like a poor man's lense.
Logged

Global Moderator
UK
Offline Offline
Brattain Member
*****
Karma: 238
Posts: 24322
I don't think you connected the grounds, Dave.
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

I assume "lense" is American for "lens".
Logged

"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

NYC
Offline Offline
Full Member
***
Karma: 0
Posts: 125
The singularity is near!
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

I played around with this and it seems better at night w/o sunlight coming in through the window and most lights off.

Overall there was about a 90 degree range that worked from 6 feet. This suggests the issue is with the receivers noise suppression.

I was thinking of trying a few receivers with different noise reduction. The retrievers have the same 3 connections, so they are easy to try. (The biggest hurdle is the cost of the shipping.) These are the receivers, I was thinking of trying: TSOP4838, TSOP34838, TSOP8238 and TSOP1138.

Also would like to try tsal7200. It is supposed to have greater range.

Any suggestions on receivers and emitters is appreciated.
Logged

Manchester (England England)
Offline Offline
Brattain Member
*****
Karma: 508
Posts: 31431
Solder is electric glue
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

Quote
Does it matter the shape of the perspex, like would a 1" circle with the led mounted in the center work?

It would work even better if you did it with a rod, because the sides would be polished.
Logged

Pages: [1]   Go Up
Jump to: