Ole-Hjalmar Kristensen wrote:
"jr" == jim rozen writes:

jr In article , Ian Stirling says...
And then you quote the brightness at the start.

jr And they quote it with the absolute max. current
jr in the diode, such that it will fail shortly
jr after the intensity measurement is finished!!

It shouldn't be to difficult to build a circuit which would give
essentially constant (and adjustable) brightness for the whole battery
life.

Just charge a capacitor, and dump the charge into the LED when the
voltage exceeds a threshold, then repeat the cycle. You modulate the
intensity by changing the threshold.

Causing much higher heating due to I^R losses.

For pretty constant, it can get as simple as a transistor and appropriate
variable resistor.
The brightness varies with the battery voltage, rather than with the
battery voltage - LED voltage.

Alternatively, a switched-mode power converter is the way to go.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
Things a surgeon should never say:
Better save that for the autopsy.