3mm brighter than 17000mcd?

[redledz]

Hello, recently a friend asked me about 3mm leds since he knew I was into flashlights. I told him my knowledge bout 3mms was pretty slim. He's looking for a 3mm brighter than 17000mcd. He would also like to run it off a 3V button cell battery.

In my own initial search it doesn't look like such a 3mm exists. I could only find 5mm with a higher mcd. Is 17000 the limit?

 

[JohnR66]

As you may or may not be aware, the candela rating is the intensity of the light emmitted in a certain direction. The same light source that is focused into a tighter beam will have a higher candela number.

This is important because 3mm LEDs do not focus the beam all too well due to their small size and shorter length. I don't believe there is such a thing with an honest candela rating. The brightest 3mm LEDs that I'm aware of is the Nichia DS (3mm version) at 12.9cd.

 

[J_C]

I could be wrong but suspect what your friend wants brightness-wise, will have a higher forward voltage than 3.0V so it could be an impossible wish without a boost circuit (or of course multiple parallel LEDs to achieve the required brightness).

 

[redledz]

thanks so much for the info guys! I found out he'd been getting some leds from an ebay seller in china. So I'm going to source some nichias and go from there!