power consumption for a given brightness

[BKarim]

let's consider a DPSS 532nm pointer and a 650nm diode pointer.
to achieve the same dot brightness (not output power!), which pointer will consume the less battery power ? (or current if you prefer)

 

[Rafa]

hmm I think red will consume a lot more than the pump diode of the greenie.

But it depends on the green's efficience and the red's efficience.

 

[Cyparagon]

In theory, you'd need about 14 times the red power (658nm) to equal the brightness of the green. An input of 1W of energy into a green laser yields 100mW (obviously dependent on many parameters) while 1W power input to a red laser diode will give about 350mW. So you'd need 3.8 W input to a red laser to yield the same brightness.

(Disclaimer: theory ≠ practice)

 

[BKarim]

cyparagon have you taken into account the efficiency of the IR diode ?

 

[Cyparagon]

I have. Typical 100mW greens use 1/2W diodes. They generally run about 500mA at 2V (1W input)

 

[BKarim]

i'm amazed. are you sure that overall efficiency for 532nm generation is 10% which is very good.


so, same question for 405nm:
to achieve the same dot brightness (not output power!), which pointer will consume the less battery power ?
(and if you can same question for beam visibility )