Physical limits to HID lumens and brightness?

[Spot]

What are the physical limits to HID lumens and brightness?

For example, do the laws of physics allow a flashlight to shine at 1,000,000 lumens? 10,000,000?

Just as a thought experiment let's assume the discovery of a super-lightweight futuristic alloy that effectively shields a miniature nuclear power source as a battery, and some kind of new lightbulb technology that is capable of shining brightly as its power source can feed it energy?

Then the question, and it probably involves some knowledge of physics, is how bright can light shine as measured in lumens? As bright as the sun? 100x the brightness of the sun? What does the physical limit translate in lumens?

Back to reality, if nobody really knows the answer or even a remote guess to my aforementioned question, what do you expect the maximum number of lumens a commercial flashlight will have within the next few years? What is the maximum lumens in a flashlight now? (Weblinks please.)

Some of my friends say I think too much.

 

[Flashanator]

hypernovers r 100's of billions x the brightness of 1 sun, Id say there is no limit in lumens, just the mass of a infinite large star required in one spot. But there is a limit in things like tempreture, speed, & mass(while moving), in the universe. So maybe u can't have too many lumens in one spot. might tear spacetime to peices . With lumens in commercial flashlights i think there still no were near powerful enough, i prefer 63,000 lumens of moded light to see while walking my dog at night

 

[paulr]

I seem to remember calculating that a midsized camera flash puts out about 1 million lumens for a millisecond or so. To keep it running continuously would mostly be a question of heat management, I'd expect.

 

[Cigarman]

Flashanator did you mean Hypernovae? Looks better on paper anyways.

 

[TheGreyEminence]

Maybe watercooling would be useful? :thinking:

 

[Flashanator]

@ cigarman,

spelling hypernovae (hypernover) is my lazy slack style of writin. lol.


some have liquid nitrogen cooled pcs, why not for lights:naughty:

 

[Eye of Unk]

The trick is to time capture light while its passive and not have the destructive heat issue.

In effect a simple strobe flash is frozen in time, visible light stasis, since it then is immovable it can essentially become a solid.

Something to freak out about.

Laser bullets can be made from laser bursts in a stasis field envelope.

A laser pointer with a short throw lens becomes a light saber.

 

[nerdgineer]

Huuh?....say what?.....:green:

 

[SemiMan]

The trick is to time capture light while its passive and not have the destructive heat issue.

In effect a simple strobe flash is frozen in time, visible light stasis, since it then is immovable it can essentially become a solid.

Something to freak out about.

Laser bullets can be made from laser bursts in a stasis field envelope.

A laser pointer with a short throw lens becomes a light saber.

I would agree with you if you were right, but then I would not be able to respond and where would be the fun in that.... ;-)

There are some significant issues with some of your arguments.... if you freeze that laser pointer in time, then it is no longer emitting any energy since energy = power * time....hence your laser pointer is still just that... a laser pointer with extremely low power stored in the beam. Now if you could create a containment field that recirculated the light such that you could continously feed it with energy then yes you may have a light saber. Perhaps you could have the stasis field outside the laser emission. However, unless your containment field had leakage, you would never see it.

The same would apply to your flash, etc. In order to light to be "perceived" from the flash, it must undergo chemical interactions with the eye... which I have no idea where it will be in time and space, hence I must continually output power from the flash in order to be observed.

In terms of laser bullits, again the same thing applies. If the light is not "moving" then how do I feed it energy... the stasis field may move, but if it stops the movement of light within it, then how do I feed it light energy which requires movement. I guess one could argue that the light moves full speed until it hits the containment field, then would slow as soon as it entered the stasis field. That could work. I hate to think of the index of refraction issues..... better have those things perfectly aligned. Of course, unless you had differential speed of light within your statis field. Of course would that laser bullit even be effective? It it collapsed on hitting an object, it may only do surface damage as opposed to a longer blast with similar energy...of course if you target is moving at the speed of light you would want a short pulse. Of course at what point does your statis field essentially just become mass? You may be just better off accelerating a mass to a rediculous speed...likely easier than make a mini statis field generator that would also need to move at the speed of light...hmmm...

My apologies to my fellow CPF members...I could not resist.

 

[Daekar]

What are the physical limits to HID lumens and brightness?

I think maybe this thread has gotten a tad OT... I think what Spot was trying to ask is, given a practically inexhaustable battery of almost limitless power, at what point does HID begin to "hit the wall?" Do HID lights simply continue getting more and more efficient and put out more and more light the more power you pour into them, ad infinitum? What are the maximum limits of HID technology?

Please correct me if I'm wrong, Spot... :twothumbs

 

[Flashanator]

mini statis field generator that would also need to move at the speed of light.

 

[jrv]

So maybe u can't have too many lumens in one spot. might tear spacetime to peices .

At some point you'd create a Geon if the light gets too intense, which would be neat to see ... from a great distance.

Slightly more realistic is that the plasma arc in a HID has a finite radiance in terms of watts per surface area. You can make the arc longer etc but at some point there's a problem where increasing the surface area of the arc doesn't add much to the lumens output (i.e., you need to double the surface area to double the output, and that gets to be very hard).

The good news is that's a very long way off. Tank lights, stadium lights, even WW2 anti-aircraft lights are *far* brighter than any personal HID (except BVH's I suppose!) so the limitations are really more mundane: power supply, cooling, etc.

 

[2xTrinity]

I think maybe this thread has gotten a tad OT... I think what Spot was trying to ask is, given a practically inexhaustable battery of almost limitless power, at what point does HID begin to "hit the wall?" Do HID lights simply continue getting more and more efficient and put out more and more light the more power you pour into them, ad infinitum? What are the maximum limits of HID technology?

Efficiency does have a theoretical limit.

The lumens are determined by weighting the radiant power output of your light source, by the above curve (sensitivity of the human eye at different wavelengths). 1 Watt of radiated power at 555nm, or the peak of that function corresponds to 683 lumens. So that's what you'd get with some sort of perfectly efficient yellow-green LED.

A blackbody-like curve (broad band) with sharp "cutoffs" at 400nm and 700nm (boundary of visible range) would produce about 240 lm/watt.

A perfect RGB source approximiating white could reach about 400 lm/watt. I expect "real" LEDs to achieve maybe 75% of that, or 300 lm/watt for white light sometime in the future.

Metal halide HID source (white) top out at about 100 lumens/watt. That's likely fairly close to the physical limitation based on the fill gases used. Sodium vapor (amber light) is presently the most efficient source in lumens/watt at as high as 200lm/W, but amber light is not especially useful.


There will also be other limitations to overall power output. As far as HID goes, I believe there's a maximum amount of surface-brightness that the arc can achieve. That means to go higher pwoer, a longer arc, and thus a larger overall lamp must be used. High power HID Lamps used in stadium and warehouse lighting for example are quite large, and I don't believe it's highly
practical to downsize them.

There are short-arc lamps used in huge projectors at around the ~1,000,000 lumens mark, those are inherently less efficient (maybe 50 lm/W) so run about 20kW. They are typically completely immersed in water that has to be continually circulated in order to dissipate the heat. I don't think that will ever work inside a flashlight due to weight constraints.

 

[Daekar]

Thanks Trinity. :thumbsup:

 

[Spot]

This is one of the applications I had in mind... picture a large billion lumen HID light in orbit (run by large nuclear powered batteries).

As it comes around to the dark side of a celestial body like Earth it turns on like a flood light in a football stadium and lights the enter half of the celestial sphere as bright as daylight. From the surface there are blue skies and a "sun" above.

Colonization off the outer planets

Suppose you could put these satellites in orbit around planetary bodies with Earthlike gravities, if such bodies are discovered, that exist so far from our sun they are in perpetual darkness. As the HID light orbits the planet it creates daylight that mimics the sun. Could such planets become terra formed? This could open a world of possibilities for bodies the size of Earth in deep space in the outer reaches of this solar system, without worrying about finding Earthlike planets in other solar systems.

Anyone venture a guess if such a HID light in orbit could light the dark side of Earth if powerful enough, and if the invention of such lighting is feasible with nuclear energy or other undiscovered energy source?

 

[java_man]

The limits are more practical than physical

For any type of HID .. there is a physical limit to the luminance
(candela per sq cm) and there is a limiting factor is the practical size of the lamp and power supply .. and this seems to be about 2KW for conventional metal halides and 20KW for the largest xenon and HMI lamps

There is a company that makes water cooled argon lamps up to 500KW used for thermally treating materials and solar simulation ... this is the most powerful lamps in the world that I have heard of