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It's sad that people thought it was real, forget about lasers and stuff it's basic common sense.

A AAA battery doesn't store enough power to drive a laser capable of burning hair for any reasonable amount of time.

When the laser isn't interrupted by the hair it has to go some where which means that heat is produced, if it can get something hot enough to burn the hair off it would get hot enough that you won't be able to hold it yet alone put it to your face.

There's no way you would ever could get the laser beam close enough to the skin for a smooth shave without burning your skin off.

And most importantly burnt hair smells like shit....

P.S. I assume that most people know at least 1 person that did laser hair removal, they should know it's a very painful and long process and it works only on dark hairs so again using this to shave anything but a fairly dark beard would never work.

> There's no way you would ever could get the laser beam close enough to the skin for a smooth shave without burning your skin off

That doesn't make sense. Of course you can remove hair with light. IPL isn't anything new, and this product is apparently from someone who has worked in that field for a long time.

> it's a very painful and long process and it works only on dark hair

.. which is exactly the innovation claimed in the video: this is an IPL-like method that works on light hair by bending them against a fiber. Does it work? I have no idea. But it's certainly not against "common sense". And there are prior patents in delivering IPL by fiber.

The final product could not have such a small battery shown in the video however. The production unit would probably be closer to existing IPL products in size. They're not impractically big, much like a hair dryer.

I've done laser hair removal, and while it does hurt like a bitch, and does only work on dark hairs, the claims were that the razor would use a wavelength that targeted all hair (I don't know enough to say that's not plausible), and presumably they'd use a short enough focal length to only hit exposed hair, rather than the normal method of focusing on the hair below the surface.

Doesn't get around the smell, power requirement, or heat output though.

If there already was a wavelength that targets all hair colour, they would use it already with other hair removal treatments, you'd think.

True, that is indeed another hole in their story.

The other is that there's a critical difference between hair cutting - which is what this claimed to do - and hair follicle killing, which is what laser and IPL treatments do.

Existing treatments are supposed to kill follicles permanently.

This suggest it trims hair but doesn't leave you permanently beardless.

They can't possibly work the same way.

So I think KS did the right thing. Too many people have been using it in scammy ways, and that makes it less effective for anyone with a genuine product, talent, or idea to sell.

Having said that - the scams only work when you have a market full of people who don't know enough about basic science or simple online research to check unlikely claims. And that's been the real problem with KS, IGG, and the rest - it's just too damn easy to make money from a few hours of 3D rendering to create a shiny sketch of a product that can't possibly work, or (at best) can't possibly be developed without far more investment.

In fairness, most people have very little idea of basic physics, and this project has something in common with the sort of extremely dubious projects even investment professionals throw their weight behind: a founder with credible-sounding paper credentials.

Also, most people are looking for a 'quick fix' to everyday troubles. Just look at how many weight loss products there are. Everyone wants an easy solution.

And laser hair removal doesn't even destroy the hairs, it uses the hairs to transmit heat to the hair follicles to destroy those. Destroying the hairs themselves would require even more energy.

I think laser hair removal is fundamentally different from what they were selling. I understand they are cutting the hair, not destroying the follicle.

We understand that which means that the laser has to be more focused and deliver higher energy density.

Hair removal products are usually in the 20-50W ranges depending on wavelengths, the lightsaber wannabe hand held lasers are usually in the 500-2000 mW ranges and while those can burn skin and pop balloons they aren't powerful enough to burn hair.

I just don't see them having the technology to make this work, if they had it would have military applications way before shaving ones.

Just for size comparison this is a laser used for soft tissue removal https://upload.wikimedia.org/wikipedia/commons/c/c7/Sharplan...

And even it won't burn hair because it works on tissue with high water content only.

It'a also worth noticing that laser hair removal usually does not actually destroy the hair its self, it still has to fall out on its own. A laser that actually cut the physical hairs would probably have to be even higher energy than typical laser hair removal which is already not safe for home use.

What's the science on "dark" hairs? Can I dye my hair and then laser-remove it?

No, because dye is only on the 'outside the scalp' part of the hair. IPL works by transmitting heat to the follicle (transmission only works on the color particles in the hair, can't remember the proper name) and when the follicle has been burned, the hair falls out.

They say they don't burn anything. From their FAQ:

Does it produce a smell?

No. Because we're not actually burning the hair, it doesn't produce a burnt hair smell.

Which sounds interesting, if it is not burning then what? Just melting?

But lasers are magical future technology though and solve every problem!

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