LDR data

[Martin Czech]

:::BTW: those LEDs were green.

I just found the old Valvo "Optoelektronische Bauelemente" book.
There is a graph for the relative sensitivity for different wavelength.
Looks like a camel, one hunch with 100% 530 nm (green, bingo),
one hunch at 640nm (orange/red). The hole in between is 75% at 560nm 
(green/yellow). Not so much dropped. At 480 nm (blue) there is only 30%
rapid fall off. The red side goes slowly down, 60% at 750nm , which is close to 
IR.

So there is good sensitivity from blue-green to deep red.

The hunch at orange is interesting, I think those superbright LEDs
are orange.

It is all expressed in %, i.e. linear. There is no thing like orders of 
magnitude. Easy to understand that a lot of different colored designs work.

I guess such an expensive super orange LED could save 50% of the current,
or even more. Interesting not only for battery supply.
Large currents will cause large voltage drops on supply lines,
you know what I mean...


A nice little book, I'll save that from the shredder.
At some intervalls they throw out all those nice old lab books.

I have to stay longer today. Perhaps I should throw that book into the scanner.
Should I?

m.c.