Laser Horsepower Advertisement - At the Crankshaft vs. At the Actual Wheels

[White-Light]

What is advertised as the power is what you should get out the aperture otherwise how do you know what you're getting when different projectors can have different internal losses due to dichro quality, mirror quality, mirror sizes and beam specs?

Otherwise eg. 1 persons 600mw projector could be 580mw whilst another 320mw.

The only sensible way to measure power that provides a meaningful comparison between projectors is post aperture.

[norty303]

I think we have to bear in mind mass production however (we all like cheaper prices, don't we?). That's why I suggested the rated power of the modules. It may not be practical to do detailed measurements of every projector off the production line, but at least stating the minimum you're going to get is the way to go.

[JohnYayas]

I think we have to bear in mind mass production however (we all like cheaper prices, don't we?). That's why I suggested the rated power of the modules. It may not be practical to do detailed measurements of every projector off the production line, but at least stating the minimum you're going to get is the way to go.

I don't think there is anything unpractical about expecting manufacturers to take measurements of what they initially produce and then subsequently spot check them. In fact, I think that should be a requirement for quality control. I could rig up an automated test rig to do the whole procedure almost as fast as the person could plug in the power cord and ILDA cable. I don't expect every projector to have the exact assembly line output powers to be stamped on it but they should all be at least greater than the advertised power.

[sbk]

Imho the best measurement for a laser projector should not even be in watts or whatever, but in something which really means something, luminosity speaking. And the measurement should be advertised at least at the aperture, or even better, at a distance such 25 meters, to take divergence into the value calculation.

No one are giving output of a standard video projector in watts. Rather in lumen !

Also white balance should be taken into account, for an RGB laser it should be measured at for example, D65 white (look here)

Also *that* will be a first solution to differentiate a cheap 5W laser projector from eBay, with 2.5W 650, 0.5W 532, 2W 445, from a real quality projector, with balanced 637, 532 and 445nm.

Some laser co are already using a more true way to advertise their projectors for renting, like this one and its calculator

[LaNeK779]

well, to take into account all possible aspects of pj operation, a rather impossible measure had to be devised

i.e. take an rgb projector, tuned for white at the higher and lower bound of pj performance. then, some math has to be done, to take into account the beam diameter and divergence, (so beams at a distance) too.

i put it very roughly here, i hope it conveys the message. what i roughly need to say is that raw numbers mean nothing if modulation and beam specs is crap. everything is subjective to how the human eye perceives it. after all, our game is all smoke and mirrors

[-bart-]

The output of a projector should be advertised in ansi-lumens !

[laserwinkel]

just advertise the total laser power and then say if it is internal (maximum) or external (guaranteed)