Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

How to measure light intensity of 950nm LED

Status
Not open for further replies.

mehoffman

New Member
I am trying to come up with a simple circuit/method that can tell me the intensity of a 950nm LED
source after the light travels through a glass fiber bundle. I was looking for a photo resistor (I
figured I coul djust measure the resistance) but can't find one that operates at 950nm.

Basically I want to measure the efficiency of my glass fiber and optical coupling mechansim. I
need to compare the output of the bare LED with the output of the fiber to see how much light
is lost going through the fiber.

I thought of buying an LED testing instrument, but can't get approval for that. I need something
cheap that I can build myself. Does anyone have any ideas?
 
A standard Si photo-detector diode is sensitive to near IR energy (see this). One of those should work fine for making relative measurements of your 950nm signals, since they generate a fairly linear current proportion to intensity level. You just connect a few volts of DC to reverse bias the detector and measure its current when illuminated.
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top