# How Bright Can A Consumer Flashlight Get, With Current Technology? **URL:** \ **Category:** Factual Questions\ **Created:** [March 28, 2019, 11:19pm UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688 "2019-03-28T23:19:30Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![HeyHomie](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heyhomie/32/207_2.png) [@HeyHomie](https://boards.straightdope.com/u/HeyHomie)\ **Post date:** [March 28, 2019, 11:19pm UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/1 "2019-03-28T23:19:30Z")
The world’s brightest consumer flashlight, according to [this website](https://1lumen.com/brightest-flashlight/#world-brightest), shines at 60k lumens. Yours for $549.00. I’ve seen YouTube videos ([example](https://youtu.be/oGDftl4rF2A)) where people dick around with 32k lumen flashlights, and my god. How far can flashlight manufacturing go, within technological limits? At what point would the FAA want a word? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [March 29, 2019, 12:50am UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/2 "2019-03-29T00:50:52Z")
The only limit is practicality. Is a car-battery sized battery OK? Because, if you want to get to millions of lumens, you are going to need a serious power source. ETS: You could probably fit 250 of [these](https://www.mouser.com/new/Luminus-Devices/luminusSST90/) in a pie-plate sized area. The, all you need is 4,000A _et voila_. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [March 29, 2019, 5:25am UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/3 "2019-03-29T05:25:01Z")
What’s a “consumer” light? E.g. [this](http://www.candlepowerforums.com/vb/showthread.php?214515-For-Sale-525-000-Lumens-Monster-60-quot-Carbon-Arc-Anti-Aircraft-light-from-WWII) (I have seen similar ones in action) is used for “midnight madness new car sales, openings of new restaurants and a few Christmas live nativity drive-thru’s.” ---
**Author:** ![Channing\_Idaho\_Banks](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/channing_idaho_banks/32/250_2.png) [@Channing\_Idaho\_Banks](https://boards.straightdope.com/u/Channing_Idaho_Banks)\ **Post date:** [March 29, 2019, 7:36am UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/4 "2019-03-29T07:36:58Z")
if only there was an online web forum where people discuss flashlights endlessly. ---
**Author:** ![joema](https://avatars.discourse-cdn.com/v4/letter/j/a9adbd/32.png) [@joema](https://boards.straightdope.com/u/joema)\ **Post date:** [March 29, 2019, 11:13am UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/5 "2019-03-29T11:13:57Z")
> [@HeyHomie](#): > > The world’s brightest consumer flashlight, according to [this website](https://1lumen.com/brightest-flashlight/#world-brightest), shines at 60k lumens. Yours for $549.00… > How far can flashlight manufacturing go, within technological limits?.. The yet-to-be-released 100k lumen light on that page uses 18 Cree XHP70.2 LEDs, each capable of about 4,000 lumens at an efficiency of 181 lumens per watt: [https://www.cree.com/led-components/products/xlamp-leds-arrays/xlamp-xhp70-2](https://www.cree.com/led-components/products/xlamp-leds-arrays/xlamp-xhp70-2) This implies at full output it requires about 550 watts, and the Cree spec sheet lists max drive current of 2.8 amps at 12v, which for 18 LEDs would be 50.4 amps. The maximum possible real-world efficiency for white light LEDs is roughly 250 lumens per watt, which isn’t far above the 181 lumens per watt of the above Cree XHP70.2. This implies that future LED efficiency gains will be limited, and for an LED flashlight or mobile searchlight, any gains in luminous output will require linear scaling of # of emitters and power consumption. IOW to get twice as bright will require twice the emitters, twice the power and commensurate cooling. The problem is the human eye is logarithmically sensitive to illumination. 1000 lumens only appears a little brighter than 500 lumens. In fact the minimum brightness increase that is easily perceptible is about 40%. White light LEDs usually do not directly emit light but do so indirectly via a phosphor, somewhat similar to how a fluorescent tube works. Given this indirect path it’s hard to believe they are so efficient and can handle such high power levels. Monochrome direct-emission LEDs can be more efficient, up to a theoretical maximum 681 lumens per watt for green light at 555 nanometers. It is theoretically possible to make a high power, tri-color direct-emission LED which combines red green and blue emitters to produce white light. It would be more efficient than a white light phosphor-based LED, but they will never reach 681 lumens per watt. For the most part I don’t think tri-color LEDs are in wide use at very high power levels. ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [March 29, 2019, 1:16pm UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/6 "2019-03-29T13:16:11Z")
> [@Channing\_Idaho\_Banks](#): > > if only there was an online web forum where people discuss flashlights endlessly. Since we used to use candles, perhaps it could be called Candlepowerforums? ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [March 29, 2019, 2:09pm UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/7 "2019-03-29T14:09:05Z")
I’m sure there’s some totally impractical hobbyist method for creating a 5000 lumen light with a battery life of 32.3 seconds, and that heats up to 150 degrees, or something absurd like that. It’s like those doofuses who use liquid nitrogen to see how fast they can overclock PCs. Utterly impractical, but interesting in a sort of academic way. That’s the thing- there are always tradeoffs. You can overdrive your LEDs, but you also increase heat, decrease component life, and use more current (i.e. less battery life). I’d think to get a useful answer, you’d need to fix a couple of those variables- something like “What’s the brightest LED flashlight that could be made with a 4 hour battery life and that will last for 500 hours” or something along those lines. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 29, 2019, 2:17pm UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/8 "2019-03-29T14:17:31Z")
> [@Channing\_Idaho\_Banks](#): > > if only there was an online web forum where people discuss flashlights endlessly. I, for one, definitely feel that we should shed more light on the subject. 😃 ---
**Author:** ![KMS94](https://avatars.discourse-cdn.com/v4/letter/k/ad7895/32.png) [@KMS94](https://boards.straightdope.com/u/KMS94)\ **Post date:** [March 29, 2019, 2:38pm UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/9 "2019-03-29T14:38:53Z")
> [@GaryM](#): > > Since we used to use candles, perhaps it could be called Candlepowerforums? I haven’t visited there in some time. Is the very strict, condescending moderator still around? His name escapes me. ---
**Author:** ![GusNSpot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gusnspot/32/436_2.png) [@GusNSpot](https://boards.straightdope.com/u/GusNSpot)\ **Post date:** [March 29, 2019, 3:12pm UTC](https://boards.straightdope.com/t/how-bright-can-a-consumer-flashlight-get-with-current-technology/831688/10 "2019-03-29T15:12:55Z")
MANKER MK35 Has one, ( 1 ), uno, a single LED 2550 Lum 1400 foot throw I got I luvves it No, you can not borrow it…