Crazy difference between 5W LASER and 5W LED!

[@jdotoz]

Counterpoint: if you use a strong enough laser, you will start a fire, which will quickly light the room much better than the lamp.

[@GRBtutorials]

Especially if you aim it at, say, magnesium powder, which also has the neat side effect of getting you tanned, thanks to UV emission.

[@AKAtheA]

plot twist - if you add enough orders of magnitude, you can light nuclear fusion with a laser

[@MadScientist267]

Trainwreck: If you drop a nuke on the building, the room inside will be rather active with the entire spectrum...

[@binaryglitch64]

Yeah that sounds@@MadScientist267.

[@TauCu]

@@AKAtheA plot plot twist: if you add even more orders of magnitude, it'll ignite nuclear fusion that ignites more nuclear fusion that ignites...

[@nefariousyawn]

Great explanation. I like how the rise in LED lighting has lead to consumer packaging listing lumens and color temperature, which makes more sense than "40 watt equivalent."

[@brainiac75]

Thanks! The lumens listing is interesting. As I've understood it, the 470 lumens is for a well-ventilated lamp. It will heat up and go lower in lumens if the lamp is poorly ventilated. May have to dig further into the topic and make some tests - possibly a video. I have an old 40 watt incandescent bulb that is advertised at 400 lumens, so the LED can go lower and still match a 40 W incandescent lamp.

[@elyeryan8838]

Also the human eye's perception of brightness is subjective at different color temperatures.

[@Gameplayer55055]

Hm. What is lumen. I need light level when my cam stop noise

[@kwinzman]

That's true. But now think of 80 year old people that have used incandescent bulbs their whole life. It doesn't hurt sales to have an "equivalent" for them on the box. Some customary units are just odd, like selling natural gas in MWh of energy that you will get if you burn it.

[@Traqr]

@@Gameplayer55055 hah! There are so many ways to measure light, depending on what you need. Lumens are total light output, adjusted for the sensitivity of a "normal" human eye. Lux is brightness of a lit surface. Nits for the brightness of a light source. Candela for the brightness of a beam of light. CRI for how true the light is to a reference white source, and Kelvin to identify the reference. That's just the start, too!

If you ever actually perceive that laser, its effective lumen drops to zero in the blink of an eye.

[@JasperJanssen]

Before you can even blink, really.

[@railgap]

what?

[@Deeem2031]

@@railgap laser + eye = blind

[@Blox117]

i thought you turn into superman

[@Blox117]

after all, the name of this channel is brainiac

[@twjackson94]

The reason you were getting 66mW at 3 percent input power is because the amplification in the laser is a non linear process much like a diode. There will be a threshold current will the laser will go from some baseline output to its full output. Qualitatively, amplification will be less than the losses in the system below threshold. At threshold, the amplification overcomes the losses, however the gain medium saturates and the laser reaches a steady state.

[@m.streicher8286]

I love the cooling solution, the heatsink design and the tiny fan. Interesting video, especially the watts/square meter.

[@brainiac75]

I like the cooling solution too. It needs to be good. For a 40 x 40 cm engraving, the laser could need to be on for hours in one go. So far I haven't felt the heatsink getting warm - promises well for longevity. Yep, W/sq m is the big advantage of lasers. Thanks for watching!

[@muhammadjalal2335]

@@brainiac75 yooo

[@darkracer1252]

it's actually terrible. i have the same heatsink here on a 2.5 watt laser and it still gets hot. (it's basicly just aluminum extrusion frame work, btw. just with some extra texture on the outside that kindof resembled cooling fins) seriously it's all just looks so the chinese can sell shitty hardware to the average dumb person at overpriced prices. (seriously a couple years ago when these things weren't so popular yet they were selling for less then half the price) i mean i bought a freaking co2 laser for less then the engraver that brainiac is trying to get refferal monies from. anyway terrible design. did you know that the annodisation reduces it's effectiveness.. it acts like insulation. wich you don't want on a heatsink. (and at brainiac. these terrible heatsinks not even getting warm with a 5.5W laser is a bad sign. it should atleast get warm, that's how you know it's doing it's job.. if it stays cold to the touch then it's not drawing the heat out of the diode and the diode will go poof in less then a month of occasional use. either that or you are using it in a verry cold room)

[@jakegarrett8109]

@@darkracer1252 The material should stabilize at a certain temp (because the thermal mass of the laser diode probably takes about 3 seconds to heat up by itself, its basically nothing, so if its running for a minute then we know its exchanging heat to the heatsink), the diode can't just keep heating up forever, once its on for several minutes it won't be getting hotter. If the material on the outside feels warm to the touch then that means the airflow is insufficient or that its heat transfer rate to its surroundings is poor (which is usually airflow unless you're using a bad material like Stainless Steel or Titanium for no apparent reason). Its just like a CPU heatsink, if its cool to the touch then you know either: the fins are sufficiently long that they are working near full capacity for that design and infinite long fins wouldn't benefit much, or that your fan is really good (and longer fins or surface treatment) probably wouldn't drive the temps much. However those of course don't mean its the best design, just that its dissipating its heat by the time it gets to the edge (which is partly why water cooling is great because it dissipates all its heat within a very short distance or you could think of it as a cold source really close with low thermal resistivity to the point being cooled). I don't have the same laser, just a similar power one (7w output, 30w input), and I will say the fan on those things is amazingly good, not as good as duel stage contra-rotating super speed class 40mm server fans (the one's I like are MagLev 40mm SS class), but it absolutely screams so you barely need any heatsink for the 25w of heat its cooling just from the brute force of air blasting it. If you're really worried about it you could sand the surface and copper plate, but I would just plop the diode into a universal laser host and make a water cooling jacket for it.

[@darkracer1252]

@@jakegarrett8109 you buy yourself 2 identical lasers. remove the heatsink off of one. and then power both of them on. you wait and see how hot the one without the heatsink is gonna get. the one without heatsink will also slowly break itself might even begin mode hopping before it dies. what i'm saying is that if his heatsink does not get warm at all that means it's barely pulling any heat out of the laser module. any laser module should produce enoegh heat to atleast get the heatsink of this size to be warmer then your body temperature. at some point it shouldn't get any warmer because the diffrence to roomtemp is bigger so the air is more effective at cooling. at wich point the laser doesn't output enoegh energy to keep raising the temp of the heatsink. don't try to tell me how heatsinks work. i think i know atleast 10 times better then you. i was just sharing some of my laser knowledge wich you don't seem to have or you would know better then thinking THIS heatsink won't get warm to the touch. with a freaking 5.5W laser. unless he is blowing refrigerated air though it. it's gonna get warm after a few minutes. (it shouldn't get HOT like my 2.5 watt one does. just warm, like my other lasers do.)

[@initialb123]

Lighting a room is very possible, when you make a mistake homing/start position and run off the work piece hitting the shiny extruded aluminium sub straight , it lights up the room as if you struck an ark welder. It is seriously bright in an eye blinding way. Glasses are not just highly recommended, they are absolutely mandatory, don't risk it, it will hurt you.

[@DrTune]

eeeh it's FINE, it's why you have two eyes after all; one is for learning the lesson.. :-P

[@Mike-oz4cv]

A very related topic is Lux ratings on bicycle headlights and torches. Sometimes they also specify ridiculous Lumen ratings which are either for the bare LED (without reflector, glass cover etc.) or only sustainable for very short durations. In the end the light pattern (i.e. the optics) is usually much more important than the total power output or brightness.

[@BariumCobaltNitrog3n]

lux can be a better way to judge the effective light because it measures light in a given area (1 square meter) at a distance, which is throw. A light may put out 100 lumens but you have no way of knowing how far the beam will go. The optics will define how far and how wide the beam. The over-hyped lumen claims in my opinion are due to consumer ignorance, having no way to verify the claims without specialized testing equipment. Companies can say anything they want. Matt Smith debunks and explains on his flashlight channel all the terms and definitions, testing every light at startup, then 30 seconds and 5 minutes. A lot of claims are only valid for the first few seconds before the light turns into a soldering iron.

[@gilaraujo]

Great video! never seen it compared like this! Also PWM scaling is not linear, so at the lower range < 10% theres a ramp up effect, then its roughtly linear to 100%.

[@brainiac75]

Glad you like it! A video I have been wanting to make for a long time but didn't have a laser strong enough to 'match' the wattage of LED lamps :) And thanks for clarifying on the '3% power mode'. Looks like this one is only running at around 1% power in focus mode. That's a good thing for such a strong laser and impressive that it even will lase at such low setting.

[@darkracer1252]

@@brainiac75 no it actually is running at 3% power. but the power meter can't give an accurate reading because of the pwm. once the laser is warmed up btw there shouldn't be any ramp up what so ever.

[@DrTune]

@@darkracer1252 PWM seems pretty sketch on these in terms of eye-safety - sure the avg power is lower so your object doesn't get thermally burned the same - but unless they're properly low-pass filtering the diode driver (not sure how well that would work anyway) you might just have very short multi-watt pulses, which would leave you with dotted eyesight..

[@f_USAF-Lt.G]

As I watched this, I couldn't remember the specific multiplier in the calculation... I just remembered that a laser being condensed light increases in multiples_not additions - as the power input is increased.

[@Speeder84XL]

It isn't PWM that causes the non linear behaviour. The light output of laser diodes (as opposed to LEDs), isn't proportional to the current. They can light up at very low current, but then when current is increased, the light output don't increase very much - until a certain point (the threshold current), where the light output starts to rise very quickly as current increases further. That threshold also changes slightly with the temperature of the diode - so it's not possible to drive a laser diode with just a preset drive current and always having it to output for example 3%. To get accurate output, it needs a light sensor for feedback (which most driver don't have, since it's not needed for most applications - in this case as a focus aid, it doesn't matter at all, if it's actual 3% output or just 1 %).

[@alexanderthomas2660]

7:35 Cool, you have locally converted your limestone into calcium oxide, which is why it turned white where the laser hit. See Cody'sLab latest video.

[@brainiac75]

Didn't know the chemistry in it. Interesting. I like how it is multi-colored. The parts that were hit at low power turned white, while the parts hit with full power turned more yellow-white. Thanks for watching!

[@ancapftw9113]

I didn't think about doing that. I was trying to figure out a better way to make calcium oxide than building a kiln. This might work.

[@billsmathers7787]

this sounds wrong to me. The base he engraved is a slab of slate, which contains mostly silicate minerals. The white color is just the color of molten and recrystallized silica.

[@ramous5182]

@@billsmathers7787 yep, I don't think there is any carbonate-containing slate.

[@davidmcgill1000]

In any case, burning an image into rock is impressive.

[@IstasPumaNevada]

3:50 I didn't know turning on a laser automatically started up Kerbal Space Program too. :)

[@theminercet]

"this is the strongest diode I ever measured" Styropyro: You gotta pump that up thats rookie number

[@Gunfighterhaft]

My cnc Laser at work: Hahaha 12 kw bitch ✊🏻

[@Wag2112]

@@Gunfighterhaft ya, but to be fair, most tech geeks don't have 480 at their work tables ;)

[@cxpKSip]

@@Wag2112 Nor do they have access to forbidden parts to get unholy 100W lasers.

[@domesday1535]

I've got a 100W infrared laser, and a CNC gantry that actuates mirrors to translate the beam through a 3D volume. The whole thing is enclosed because there's a lot of ways that arrangement can become very dangerous, though it doesn't take quite so little power density to be dangerous since the light can't enter your eye. It will, however, cut through/boil your eye since it's so powerful

[@jaytea3299]

Cool! You should do a video of it in action, even if you can't see inside while in operation you could show it off on here...

[@tuxontour]

You can try like they do in modern headlights. Point the LASER at the phosphor of an ( better old) LED be advised it is very bright as it is a pointsource of light .

[@TaagR]

Try putting a COB LED under the laser and it will be a lot brighter, the phosphor gets excited like how blue LEDs become white. The color of the laser becomes yellow/whiteish, I believe laser headlights work this way. Would be interesting to see how many lumens per watt it would be then, or if it is efficient at all.

[@naota3k]

6:27 it's truly frightening to see _you_ being incredulous to how powerful your laser is.

[@brainiac75]

True story: During the planning of the video - before testing the laser's power - I bought as many different LED lamps I could find in the 4.5 - 5W range. I expected the laser to be in this range and wanted an LED lamp to match it. I couldn't believe it turned out to be that much higher in power... Luckily I did find a perfect match for it afterwards :) I do have great respect for this laser. I am used to handling lasers up to around 2 watts. This is in a different league (though the safety procedures are exactly the same). Thanks for watching!

[@DustinWill]

Yeah, I am blessed to work with high quality 20W fiber lasers every day, and they do command respect. Very fun work AFTER safety training, of course!

[@darkracer1252]

@@brainiac75 it's going to be in multiple comments so i can figure out what SINGLE FUCKING WORD is triggering the youtube algorythm to delete my comment.

[@darkracer1252]

@@brainiac75 anything above 1W is in that diffrent league. you are going to need goggles with atleast OD5 (though with 5.5W i would up that to atleast OD7 wich is the highest you can get) i bet they gave you the wrong color goggles aswel. if you have the correct goggles you should not be able to see the laser or laser dot AT ALL no matter what you shine it on. if you can see the laser dot. then you have the wrong glasses (or if you are lucky maybe just a little underrated glasses) and your eyes are in danger of getting damaged. don't say i didn't warn you. and next time please don't buy ANYTHING off of alieexpress anymore. test

[@darkracer1252]

@@brainiac75 ordering leather, and getting pleather. wich all seems fine. it's just knock off leather. but they were selling it intended to be laser engraved or cut. and you DO NOT want to laser engrave or cut pleather. (why? because it's made out of pvc... basicly it will release chlorine gas. that's that gas that was banned by the geneva convention that they used in WW1.. if it comes into contact with water it turns into hydrochloric acid.. you know, the stuff that melts entire corpses in bathtubs.) it will destroy your machine over time. and it will poison you aswel. and they were being sold as laserable sheets of leather. and a bunch of other things that would straight up get someone sent to prison for life on the charges of murder by negligence, in certain places test

[@jk-mm5to]

I have collected many of these Chinese engraving lasers in several wavelengths and optical power outputs up to 10 watts. So fun, so cheap and so very dangerous.

[@rc3d490]

what Chine laser do you recommend? I see many lasers labeled as "80w" with 2 diodes.

[@roxasparks]

Where and how cheap!?

[@jk-mm5to]

@@roxasparks I tried responding with ebay links but youtube deletes these

[@roxasparks]

@@jk-mm5to aw maaaan.... can you tell me the website and maybe product name and i could look em up?

[@jk-mm5to]

@@roxasparkssearch ebay 30W CNC Laser Module Head

[@Gunbudder]

I ran into the confusion with power output over area when working with RF antennas. With only changing the physical shape of an antenna, you can go from a fairly weak received power to a received power that is so high that it instantly destroys your antenna electronics. I was able to wrap my head around this by thinking of light bulbs vs lasers. an omni directional antenna is like a light bulb, shooting a little bit of power in every direction. a highly focused antenna (like a yagi) is like a laser, focusing and concentrating all of its power into a very tight direction. I sometimes also think of it in terms of imagining that the power is discrete chunks of RF energy. With a given amount of "energy chunks" input, you can throw some of them in every direction, or throw all of them in the same direction. This can be shown with a gain pattern to physically see what an antenna is actually doing. Considering that light is also RF (kind of), you should be able to draw a "gain pattern" for light as well. that would be an interesting thing to see

[@magnumopus9058]

It's all electromagnetic radiation after all

[@TheEvertw]

4:00 - love the little flashes of dust particles being incinerated.

[@ponzischemer1424]

Many years ago, early 2000’s, we used industrial carbon dioxide lasers for welding steel via lap or butt joints. At the time, we used 6,000 watt CO2 high frequency lasers. Parabolic mirrors with focal lengths of 200 or 250 mm could achieve 0.8 mm and 1.0 mm spot diameters, respectively. That’s 11.9 billion watts/square meter. And those laser beams are invisible. Love lasers.

[@sgoldon3886]

I hope you are fine. Which are the best goggles available on Amazon to avoid ALL COLORS AND POWER OF CLASS 4 LASERS?

[@lucasdiniz5642]

Very helpful video, I was lighting up my room with a co2 laser all this time XD

[@elyeryan8838]

A powerful infrared laser heating up a thoriated mantle from a kerosene lantern? That would be interesting

[@brainiac75]

Hehe, CO2 lasers are so far into the infrared, that their beams all have 0 lumens. Unless they heat something up to be red-glowing hot or set it on fire. Then you'll get some lumens to light up the room ;) Thanks for watching!

[@Scrogan]

The interesting thing about CO2 lasers is that their wavelength is more or less the blackbody wavelength emitted by an object at room temperature. But no, you can’t make a thermally pumped laser.

[@ShieTar_]

@@Scrogan But you can heat your room with CO2 LASERs, and it will be much more pleasant than conventional air heating. Assuming you manage to defocus the LASER to illuminate your hole body, instead of just burning a hole into it.

[@taiwanluthiers]

I had thought about the blue laser LED engraver but went with CO2 lasers instead. The CO2 has much higher wattage, mine can go up to 80 watts. Unfortunately it can't really focus down to as fine of a point so it doesn't work as well for very fine details, or for cutting metal (you really need about 300 watts for this). Another thing: CO2 laser is actually safer for the eye compared to visible light blue laser, because you can't see the backscatter of the CO2 laser since it has such a long wavelength. So as long as you keep the box closed you are fine. The burning effect from it can be a bit bright however. The danger with CO2 laser is you can't see the beam and it will FRY you on contact!

[@reggiep75]

10:50 - This video did clear up a few things I'd hypothesised on as input/output energy is different, on different wavelengths and other factors and this tidied it all up... And lasers are still most definitely to be respected, no matter what.

[@mbuurmei]

Watt I presume😅

[@Basti5792]

Brainiac has to live in a triangular shaped house. In one corner he stores the magnetic stuff, in the second corner he stores the radioactive stuff, and in the third corner he stores his lasers. :D

[@Lohoydo]

I like the yellowing you got on slate. I use CO2 and fiber lasers at work on occasion, so appreciated your explanation. I'm just glad its an enclosed laser so I don't have to worry too much about laser glasses

[@KiwiKoNZ]

A 5,700mW laser … that’s incredible! 🤯👍✨

[@jk-mm5to]

How many femtowatts is that?

[@anullhandle]

@@jk-mm5toAtto boy lol.

[@TubeNotMe]

I already knew about the difference, but it was still great to see the specific figures and demonstration!

[@MrBlaDiBla68]

"If you want to light a room, a strong laser is not the right choice." Well thank you :-)

[@ronnetgrazer362]

I've been think about a lighting solution where UV lasers are pointed at slabs of phosphor across the room. I can't be the first one to have thought of that, but I tested it and it looks great. I'd have to tweak the phosphor mix for a proper profile, though. It would be interesting to see the efficiency of this remote phosphor approach. I'm guessing it won't beat that same phosphor on a blue LED.

[@williamhuang8309]

It depends on what "light" means it could well mean that he wants to light the room on fire in which case the laser is a great choice... and also a great way to go permanently blind.

[@hullinstruments]

I’ve spent years working with test and metrology equipment used to measure and characterize laser diode‘s and other related photonics stuff.... it’s always fun trying to explain to friends and clients the difference in optical output power.... compared to their understanding of normal wattage. I must have well over 1000 Watts of diode laser power in my lab at the moment...... scattered over dozens of small and medium sized lasers and modules. And it’s always difficult explaining to folks how a half of watt optical power can totally blind you in an instant faster than you can blink.

[@earlmcnulty4665]

Whew glad I came across this video, I was about to replace all my old incandescent bulbs with 5w lasers, no I know I should the 5w led bulbs. Thanks a ton!

[@Technicotop]

Put some paper tape on top of the wood you are engraving, it will prevent fumes from coloring the ungraved parts :)

[@tschichpich]

It's like pressing down with good force on your hand or focusing the force by pressing on a nail on your hand. I think it's a good analogy to understand that one will hurt more than the other

[@FakeJeep]

Another way of thinking about it... One is omni directional. The other is focused on a .77mm? point. Both have the same power.

[@madkills10]

Wow an American using metric

[@FakeJeep]

@@madkills10 even growing up the American system made no sense to me. The older I got the more things metric was used for. Even my favorite game is entirely in metric. I honestly wish they would stop using it, but our education system is fractured and useless.

[@Shabbymannen]

In horticulture, the light intensity is measured in μmol/s, called PPF. The mol or μmol is the same unit used in chemistry, and μmol/s is a count of individual photons per second, 1 μmol being about 6 * 10^17 photons. Light density is measured in μmol/s/m^2, PPFD. I think it's a pretty cool measurement, and it makes sense in its context. Lumen and similar units wouldn't make sense, because how bright our eyes perceive a wavelength of light doesn't matter to a plant. Watts doesn't really make sense either, because in the photoactive region of light there are peaks of activity. There are two peaks in the blue and two in the red parts of the spectrum as far as photosynthesis goes, so say a more powerful blue photon of shorter wavelength that misses these peaks will not be as active on the chlorophyll as a slightly less powerful blue (or red) photon that hits one of the blue (edit: or red) peaks perfectly. Wattage doesn't matter if the spectrum of the light source is no good for the plant. There are plenty of other peaks, even in the uv, infrared and far red that will affect a plant in terms of production of hormones, growth factors, phytochemicals etc. Green light is mostly reflected, but this also means it will reflect and penetrate deeper into the canopy while still having some activity, and plants can use it to determine how much foliage surrounds them locally. Thus you use PPF/PPFD. You count photons, treat them as equal, look at the spectral distribution of the lightsource, and compare this to desired spectrum for your particular plant and the growth patterns you are looking for.

[@hrissan]

That unit of measurement makes so much sense! All those lumens lux watts are a bit cryptic...

[@Fozzedout]

I was at an anime con yesterday, and they had a laser engraver active at a stall without the shield and no safety glasses, so you could see the engraving directly- should I be concerned?

[@jiriwichern]

If it can engrave 'normal' (not specifically photosensitive) materials, it can engrave your retinae. The focused light the laser emits does get dispersed by the etched material. But even then the light (especially when it's blue) is still intense. Even 'though you may not think it is (as explained in the video (in the luminance part), blue light is perceived less bright than, say, yellow, for the same amount of energy and dispersion involved). And if it should hit any (more) reflective surface (an inconsistency in the etched material, a programming or gerber fault or maybe even an accidental bump of the table which sends the head to a position it's not supposed) and a larger part of the light is directed in a single way, I'd not like to be the poor person whose eyeball gets hit by that light. However, if you walked away from the situation unharmed and a day later still have no complaints about your vision, I'd not be too bothered about it, yourself concerning. Still, especially at public events, or any event where there are people not constantly aware of the dangers such high output lasers can cause, I'd consider it reckless to display such a machine especially with safeties removed. And if everyone is aware, I'd still consider ignoring such safety measures... stupid.

[@Fozzedout]

@@jiriwichern thanks, it was a violet colour, same colour as what was used in this video. I'll send an email to the event organisers and alert them of what happened, as I'm sure they weren't aware of this either. I didn't stick around for long, so it would have had little effect on myself

[@the_retag]

@@Fozzedout was it maybe in a shielded container, basically a box made of laser goggle material?

[@Fozzedout]

@@the_retag nope, it was an open laser engraver - they were doing wood etchings on it. No cover, no glasses, just working away in a crowded area

[@judlex7300]

@@Fozzedout it means that the eat delicius banane 🍌 farts of shit mixed by big among us imostor ass

[@Bouzsi]

The main difference between a 5W laser and a 5W LED bulb is that when I shine a 5W LED bulb at the floor, my cat doesn’t chase it around like a psychopath on a three day meth bender.

[@stephenrocks7004]

Finally a man that can explain the true value of ohms law, a simple mathematical formula, where the simple can understand simple. I.e.A 60 watt lamp consumed 60 watts, where 60 watts of illumination consumes far less power for fluorescent or L.E.Ds. So now when load is determined” V/A is used. Not watts of illumination, or lumens.

[@JxH]

Using a cheap red laser pointer, I aimed it at a frosted glass lamp fixture and was amazed how the glass became brightly illuminated. I would be an interesting experiment to try (carefully) with the 5.7 watt laser. The frosted glass fixture is the nearly spherical glass covering, perhaps 20 cm in diameter, as used on the very cheapest ceiling fixtures.

[@f_USAF-Lt.G]

The "Fiber Optic" theory... Light diffused within the glass plate_ intensified by the prism effect of the "frost" (etchings are decorative - glass flaws - that have prism properties to it) LED light in a tube with a magnifying plate extending out_ is the best page light magnifier of all the book lights on the market: The light is carried through the glass to whatever it touches

[@keithw4920]

In terms of efficiency, how does LEDs (most efficient color) compare to lasers? In terms of input wattage vs optical power output.

[@SQ-619]

After Months, I Remembered The Channel's Name! You Inspire Me A Lot! And Thanks For Your Content.

[@brainiac75]

Glad you are back :) Remember to subscribe and click the notification bell/all this time ;) Much more to come!

[@XanderDorn]

W/m² is my favorite unit. When you express W/m² in SI base units it is kg/s³

[@erikpoephoofd]

Can you explain this? Where does the kg come from?

[@XanderDorn]

@@erikpoephoofd one Watt is one Joule per second: W = J/s one Joule is one Newton applied over the length of one meter: W = (N * m) / s one Newton is the force you need to accelerate one kg by one meter per second in one second: N = (kg * m) / s² ||| W = (kg * m²) / s³ so one Watt per square meter gets rid of the square meter in the denominator: W / m² = kg / s³

[@jerry3790]

Could you use a laser like an LED with a beam disperser.

[@GeekIWG]

An excellent and well indepth explanation. You're answering the questions I never thought to ask!

[@alf_1779]

KZbin recommended this video and I thought it would be interesting. It didn't take many seconds before I could hear that the narrator is Danish. Fortsæt det gode arbejde 👍

[@MinkSquared]

you know, because of styropyro im not even phased by those "tiny" lasers anymore, he's really spoiled me

[@Cobb]

You said you were going to show a montage of what the laser can do and I got a commercial for Loki. That's a lot of power.

[@Muonium1]

The secondary fluorescence peak of the LED bulb looks suspiciously lopsided, as if it were a composite of two peaks. Perhaps they have finally started incorporating a europium based phosphor with the cerium doped YAG that has been common for the last decade to make a more pleasing full spectrum warm colored low K temp light.

[@Rob337_aka_CancelProof]

That slate engraving looked tight. I wonder how it would look on granite, marble, or obsidian or maybe even something like mother of pearl

[@JoeTaber]

Great framing for a video, and excellent explanation to match. Appreciated calling out the specific factors to consider when evaluating a bare "wattage" number without context.

[@YonatanAvhar]

Every laser cutter I've ever used was always in a box that has to be closed for the laser to output anything, with a small harmless laser pointer for me to look at, why is yours open like that?

[@tissuepaper9962]

Because all that crap is totally unnecessary in a home shop environment and is only included in those products to appease OSHA. Nobody wants to be constantly nagged by their tools, it makes them less useful and extremely unpleasant to work with. If you're dumb enough to plug the cutter in or enter the same room without glasses on, you shouldn't own or operate a CNC machine of any kind.

[@davidhalliburton8594]

Brainiac75: as a fellow video producer, I've got to compliment you on the quality of your video! The sharpness, color, and contrast are all astounding! I have to ask: what camera did you use to shoot this video? Thanks

[@erikandersen2477]

Even I understood the difference, no wonder your channel is successful😄 'og god vind fremover' 🙂🇩🇰

[@bzqp2]

The engraver you show is god damn terrifying. This thing needs a full enclosure ASAP. I wouldn't show that thing in a YT video, let alone advertise it... Someone will buy it and blind a curious child who happens to walk in the room while this thing is working.

[@greedo69]

i love the "hi" at the begining of all his videos

[@geethug6910]

I just finished a project that used a 12 kw laser. The generator is the size of a minivan. I was in a weld booth once with a 6k power source with protective goggles and my skin started to tingle quite a bit and that was the last time I ever did that. I would be very interested to know what the military is doing with 50kw plus generators.

[@hrissan]

Or recent military projects where laser is connected to 100 megawatt reactor...

[@derdotte]

one more important part about lasers is its beam divergence. Simply said its connected to the power density but it also gives a better understanding when talking about what lasers do. Beam divergence tells us how far over a specific distance a light source diverges in radians. For example a light bulb has about 300° light cone therefore its entire power gets spread on that 300° cone. A lasers beam divergence however is usually waaaaaaaaay below 1° in fact we measure it usually in milliradians. This tells us that a laser bundles the light incredibly well which explains the insane power density we see in the video. There are also other important factors why lasers are incredibly dangerous but beam divergence and the therefore high value of power density is by far the most important factor.

[@Edgar-so9of]

You should make a DIY lower cost metal 3D printer video. Would like to donate to a project like that.

[@hquanngd]

Laser: hits 5W Brainiac: PLAY HEAVEN MUSIC

[@mnamnam6061]

Thank you Brainiac for that. I hope that opens eyes even for the fully uninformed playing with the guns. Just if they also realize about the plasma forming new particles that should not be blown into nature or even inhaled in a room. 👍

[@GeorgeDiwan]

Amazing video quick tip from an artist perspective if you cover the wood you want to engrave in painting tape beforehand it will eliminate the scorching and give you clean lines

[@greghawkins1025]

You speak excellent English. I'm proud of you. I apologize for not being able to speak your language. I can speak a little bit of Japanese.

[@TushhsuT]

Nice video! Just I find that units Watts/m2 are a not terrifying enough . Just recalculate how much power will enter your eye through the iris and compare that one. You even can down-grade the power as it would be reflected - just about 10%, that is normal reflection from a glass plate.

[@stephendenysov3442]

Exiled Kingdoms soundtrack fits this kind of video perfectly

[@Arbiter099]

0:50 what does the scouter say?

[@AlexKall]

Really liked the format in the beginning with my Sony phone 😁 Great video on the laser!

[@robsycko]

Very informative. And well spoken.

[@peromic]

Ville sådan en laser bandit kunne gravere på anodiseret aluminium? Er totalt rookie på dette område 😅 btw fed video, hermed abonnent + fuld smadder på notifikationer 👍

[@kawzmOS]

Great video as always! Thanks for sharing with us! ❤️

[@Mrbobinge]

So, Watt you're saying is - brilliant! Thanks.

[@FVLMEN]

We're acknowledging ken wheeler who's the one who always brings up the 5 watt light bulb vs 5 watt laser analogy right?

[@brainiac75]

Sorry, I don't know him. But it sure is a good comparison. Lots of interesting details hiding in it. Thanks for watching!

[@namshimaru]

love the safety warning on this one.

[@sgoldon3886]

I hope you are fine. Which are the best goggles available on Amazon to avoid ALL COLORS AND POWER OF CLASS 4 LASERS?

[@ladislavseps4801]

What about pointing the (blue) laser to the (warm white) led to use the phospor layer to make the light white, it shoul a make powerfull point light source. (and maybe compare it to the led bulb) I assume that it should work, it is how the laser car lights work.

[@medexamtoolscom]

You're definitely underestimating the efficiency of regular LEDs. It is my understanding that modern LEDs for lighting are about 50% efficient, so if it's 5.5 watts of electrical power in, it's probably generating 2.5 or 3 watts of visible light.

[@bricaaron3978]

But not all of the light that is actually generated escapes and is usable, right?

[@Anquarza]

Finally You Upload A Video!

[@jprakash7245]

Good info,... but why you did mask the laser working from camera, especially at those engraving scenes?

[@MoatenGat]

Holy Hallelujah. Yeah, that was pretty cool. I need a laser etcher for my desk at work.

[@Ramog1000]

and to add to the problem, laserlight actually has basically Negative Temperture in Kelvin which is a complex concept (to put it simply, negative Kelvin temps are hotter than positive temps). The laser is hotter than any normal object that has positive Kelvin temps, so it can heat up things to pracitcally any tempreture in the positive spectrum if its just focused enough. en.wikipedia.org/wiki/Negative_temperature This also allows the focusing of the beam to a much "brigther" dot of laserlight as far as I understood. As other light systems never get hotter than the source emiting something even if you focuse it down.

[@eugenes9751]

Idunno if you're aware, but you can purchase 40w co2 laser cutting machines (with everything included, including gantry) for ~$400 delivered on ebay.

[@ChrisFredriksson]

Another awesome video! Your sounds and music is just pure amazing, complements the content and your commentary more than perfectly! Can't wait for next video!

[@szczepanmejer1434]

I guess you meant this music: kzbin.info/www/bejne/qorLaaRur5eeedk

[@ChrisFredriksson]

@@szczepanmejer1434 Oh wow!! Thank you Szczepan! 🤍

[@Iceflkn]

I liked your safety bit but I'd suggest adding that the watcher has nothing to fear about watching this video as the TV screen and phone screen can never create a laser beam to damage their eyes. I've known quite a few people that do not understand this.

[@NicksStuff]

5:43 can you concentrate the beam with reflectors, though?

[@mbalunovic]

The sensitivity graph you refer to is for our "day" light sensing cels. For night time we have other which see in more like "gray-scale" but are kuch more sensitive, and they are more sensitive to blue light.

What if you could focus all of the LED lamp output to a single point like the laser does? The different wavelength spectrum would still weaken the beam, but I bet you could also engrave with it.

[@ideasolar3601]

Great video, I enjoy it, warms regards since Mexico

[@Grocel512]

That cooling with heat sink and fan is impressive. That laser surely doesn't play around. I can't wait for Linus Tech Tips to water cool that thing like it was a gaming PC.

[@Egg1456]

Not that most people would understand but a discussion about semiconductors and pn junctions would help some understand the physics if what is going on a bit for those who were interested.

[@Chriss2370]

Yes, yes very well done indeed. Very emotional!

[@thegiantgaming7592]

I loved the comparison to the led bulb!

[@brainiac75]

Glad you liked it! It is a video I have been wanting to make for a long time. Just needed a laser powerful enough to 'match' an LED lamp in wattage :)

[@colmaguson8129]

Incredibly great visual explanation! 👏

[@nst6563]

I have an 8w laser I put in a handheld host and it will definitely light a room. Unfocus it a bit and point it at a white ceiling and if all you want is intense blue light then you're good lol. May not be the best for your eyes, but it's a beautiful blue.

[@MyMy-tv7fd]

I assume that the cool white LEDs last longer too, just my impression, but you appear to give explanation as to why

[@stevosteve]

Superb, absolutely superb. Great video explanation. Learnt a a lot. I knew well the W=AxV formula but I just could not relate this to this modern world of lighting and lasers. NOW I understand.

[@paranoiia8]

Well it's like 1kg of rocks and 1kg of feathers. It's both 1kg, but one throwed can kill you other can help you sleep in the bed... ... Also yes, 1kg of feathers is heavier than 1kg of rocks because you actually need to contain those feathers so you need to add weight of bag 😜

[@BridgerBaus]

I am going to make the argument that 1kg of of feathers is lighter because it displaces more air.

[@GraveUypo]

i'd argue 1kg (mass, not weight!) of feathers is lighter because it has a much higher volume (feathers are hollow after all, and way less dense to begin with) and surface area, and thus much higher buoyancy.

[@RabterPlaying]

Nice video! Which software are you using to generate the g-code for the engraver?

[@brainiac75]

Thanks :) I am using the free program LaserGRBL. Just import a picture into LaserGRBL and it will generate the g-code. I am new to the laser engraver community, but it is surprisingly easy. The hard part is getting the power and engrave speed right for each material. That takes some experience.

[@RabterPlaying]

​@@brainiac75 Thanks so much! I have a CNC-router and mounted a "weak" laser to it. It can only engrave wood. But i wanted always to engrave a picture but didnt know which software can convert it to GCode. Btw: There comes a video idea: Comparison: Cheap vs expensive Laser goggles. I once saw at aliexpress a 2$ laser goggle that looked identical to a Bosch 60-70$ goggle. I was wondering: what's the difference?

[@dopiaza2006]

CRI is a very important value for LED lights. Low CRI (

[@zUltra3D]

Really nice explanation, definitely cleared up a lot of confusion in a fun way.

[@ronsku57]

Yess new videoo!!

[@brainiac75]

Hope you like it as much as your comment implies x) Thanks for watching!

[@JohnnyMcMenamin]

I thank everybody who uploads 8K & 4K videos.

[@DoctorOnkelap]

perhaps it is useful to make a comparison between sunlight on a warm day and the same sunlight focussed by a lens onto your arm...

[@PrzemyslawSliwinski]

A CD disc is not good in metering a power, but performs quite well when one is interested in a spectrum only and doesn't mess around with lasers, I suppose?

[@DrB1900]

Maybe it was stress from the day, but I laughed for quite a while at the light bulb + big magnifying glass stone engraver.