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How can i build a burning laser out of an LED? What else will i need to create this? Answered



It is physically impossible to create a laser form an LED. A laser has optics designed to focus the beam, and is constructed differently to impart maximum energy into the beam. A LED is for lighting purposes and does not output anywhere close to enough power to burn anything. Remember that a 80mW laser buns only in a pinpoint area. A LED diffuses light over an area.

i have one of these and i was wondering how i could make a laser out of them.


Haven't you heard of a focused led laser they are those cheap ones the that are only focused for the first 50m.

Yeah, but you are essentially overpowering the LED, which can lead to heat failure. A laser diode would be a better choice

Well yeah I NEVER suggest to overpower an LED. I would definitely suggest using a laser diode expesialy if you plan on burning more than matches and black tape.


You can't make a burning laser out of a conventional LED. You need a laser diode which is a type of Light Emitting Diode. There probably is a way to focus a burning beam similar to a laser from an LED, but you're getting into an extremely complicated optical project. Just buy a laser diode module on the internet or get a diode from a DVD drive or BluRay; it's easier.

DIY Emilio you are technically correct that you can't make a coherent beam with a regular LED therefore no true laser. However, there is no requirement for coherence to burn something. Haven't you ever used a magnifying glass in the sun to burn stuff as a child? You absolutely can focus the light from an array of diodes to burn something. A laser like beam can be made from a diode or any other light source very simply. I made a burning beam from a 500 watt halogen lamp, scrap plywood bits, some mirrored aluminum sheet from the hardware store and some epoxy putty.
1) Cut two squares of the shiny aluminum sheet (leave the protective plastic on) using a dremmel tool.

2) Drill a small hole through the exact center of one of the plates from the back side into some more scrap aluminum to avoid tearout. It is helpful to use a drill press for this and to only pierce the aluminum with the very tip of the drill bit or stop just short when the front side starts to dimple then poke through from front (plastic side) to back with a pin. this is where the beam of light will exit. you can always make it bigger later.

3) Trace around each aluminum square on a piece of plywood 2 inches bigger in length and width than the aluminum for an inch margin on all sides.

4) Glue wood blocks around the lines you traced so that the aluminum fits snugly. Also, drill a big hole in the center of one to let your beam out of one side or you can let your beam do it later (kidding).

5) Stack 3-4 layers of index card on one side and push the aluminum, plastic side out, into the box you just made. Congratulations, you just made a cylindrical concave mirror. do this for both sides being sure to get the pieces with the holes together.

6) peel off the plastic to reveal the mirror surface and stick the two mirrors facing each other to another scrap of plywood 12-18 inches apart using epoxy putty. Orient one mirror vertically and the other horizontally.

7) While the putty is still squishy, light a stick of incense and place it so the smoke wafts between the two mirrors. Place a light in between the mirrors and use the light reflected off the smoke to visualize the beam and tweak the adjustment of the mirrors until you get a centered beam that goes out the hole.

8) Mount your bright light source in between your mirrors as appropriate

9) Build an enclosure for your ghetto pseudo laser

10) Burn stuff!

In actual practice it worked better to place the light behind not between the reflectors and funnel the light through a crack between the rear reflector and the top of the enclosure with aluminum foil covered cardboard reflectors. I made the enclosure of aluminum foil covered cardboard as well. This beam diverges faster than an actual laser but you can fix that to a great degree with a few lenses. I estimate it had at most 10% efficiency. but 10% of 500W is still 50W! BE CAREFUL!!!



Answer 7 years ago

mine is blue. mine was the i don't think they make it. MTHF1000-bl.

If you get a LED from a DVD player and connect it to a battery, it will ignite a live match at 3 metres. It is extremely dangerous. Search the web for a project that shows you how to remove the laser diode from a player and shine it onto a match. I remember seeing the project last week. So it will still be on the web.

People are nay-saying that have no clue what they are talking about. Power IS not the difference between a laser and an LED. In fact, common LEDs emit more radiation than the most powerful diode lasers. The key difference in coherence. The LED source is, by nature, incoherent. The laser, in contrast, is highly coherent. Working on the same phase-front, the coherent light is able to be more effective where it is absorbed. Steve

sorry man, but you can not use a led to make a burning laser, but, you can use the burning laser flashlight hack instructable beacause it works very well because i have personally built it and love it.

i don't think lasers use LED's but if you wanted to use a LED to make a burning flashlight buy a superbright led try p7 bin c LED's made by Seoul Semiconductors, they're the brightest right now and i'm sure you could focus the light using a lens or a parabolic mirror to burn stuff

No. An LED is not a laser, those are two different things. The light emitted by an LED is not focused at all, you cannot create a burning laser with an LED.

Depends on the LED. If you get the right LED-a laser LED-and it can handle enough power (over 100mW-laser pointers are 5mW or so), then you can hook it up to a power source (battery or whatever) with the right voltage for that LED.