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elrond.406
04-18-2014, 12:25 PM
Has anyone played with making a blade for a laser, similar to Wickedlaser's Lasersaber?
I don't like their "magnetic gravity powered activation" implementation (point the tube downwards so the reflector ball falls to the tip).

Silver Serpent
04-18-2014, 12:53 PM
Lasers by design don't diffuse light very well. All the light is travelling in the same direction, and it would be difficult to light up your blade properly.

If you get it to spread out a little bit, you're still dealing with dangerous levels of brightness. If you spread it out a lot, you'll end up with a blade that has less brightness than our current generation of LEDs. A typical laser pointer is only a few mW of power. We routinely use 3-10W LEDs in our sabers. Granted, that's comparing apples to oranges, but you'll still end up with a dimmer blade. The biggest reason a laser appears so bright is because ALL of the light it emits is concentrated in a small area.

Experiment with it if you like, but be prepared for dim blades, and please, please, PLEASE wear eye protection.

RavenXp
04-18-2014, 01:16 PM
That's the main reason I didn't invest in the laser saber blade when I got my Arctic, too damaging to the eyes. Cool effect but really not worth the risk.

elrond.406
04-19-2014, 04:36 PM
Lasers by design don't diffuse light very well. All the light is travelling in the same direction, and it would be difficult to light up your blade properly.

If you get it to spread out a little bit, you're still dealing with dangerous levels of brightness. If you spread it out a lot, you'll end up with a blade that has less brightness than our current generation of LEDs. A typical laser pointer is only a few mW of power. We routinely use 3-10W LEDs in our sabers. Granted, that's comparing apples to oranges, but you'll still end up with a dimmer blade. The biggest reason a laser appears so bright is because ALL of the light it emits is concentrated in a small area.

Experiment with it if you like, but be prepared for dim blades, and please, please, PLEASE wear eye protection.

Thanks for the reply. I have a 2W laser diode (with proper protection) and I can get its beam fairly girthy depending on how I focus it.
It's certainly dim compared to the luxeon-powered blades in my sabers, but I'm curious about how WickedLasers diffused their lightsabers because they certainly look brilliant in their advertisement campaigns.

Can anyone with lasersaber experience weigh in?

Forgetful Jedi Knight
04-19-2014, 04:52 PM
It looks to me like they use some kind of focusing lens, and a super small diameter tube. Since they're basically a gimmick IMO, none of the saber smiths I know have bothered to look at them at any length, or with any seriousness. You could always ask them how they do it, and see if they'll tell you.

Sevinzol
04-20-2014, 05:52 PM
The LaserSaber "powers up" and "powers down" within a magnetic gravity system, so you can watch the most powerful lasers in the world climb the length of the blade as you turn it off and on. The laser is diffused by a built-in optical element and distributed evenly throughout the blade. A metal sphere suspended inside the tube causes the beam grow effect, while a magnet hidden in the tip of the blade causes the ball to magnetically lock into place, forming a beam with a solid end point

Sounds like they use a polished ball bearing and 2 magnets, 1 fixed (on tip) and one electro (in hilt). I bet you have to point the blade down when you turn it on so that the ball rolls to the tip with air resistance, then sticks there to the magnet. I note in the saftey section, it is to be used in a "controlled environment" That means even though its a thick walled poly-c blade by our standards they don't want you to actually fight with it. Frankly I wouldn't want the "metal sphere" to go shooting across a room when the tip comes off. Sounds like an expensive dust collector you can't do much with for fear of getting arrested by the FAA (https://www.faa.gov/about/initiatives/lasers/hazards/)