Mechanically Scanned... with Lasers??? Can I do this?

I've been thinking about building this mechanically scanned video game system for a while now: **broken link removed** The thought just occurred to me, that I might be able to use laser diodes in place of LEDs. That way, the image could be projected on walls. Can I do this? Would the results be clear enough? Thanks.

Rain

Electric Rain said:

I've been thinking about building this mechanically scanned video game system for a while now: **broken link removed** The thought just occurred to me, that I might be able to use laser diodes in place of LEDs. That way, the image could be projected on walls. Can I do this? Would the results be clear enough? Thanks.

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I think you probably have an exaggerated idea of what laser diodes can do?.

um, I don't see why the project couldn't be converted to uses lasers, (probably need more than a few laser diodes though...), however the image on the wall would be 'stretched' in the direction of the rotation somewhat (because of the higher distance that it is being projected over). Also, unless you were projecting it onto a wall with the same curve as the arc of the projector, the image would be distorted even more (it would get stretched more at the edges than in the middle).

I don't see why it couldn't be done, but I don't think it would as simple as replacing the LEDs.

Tim.

Nigel Goodwin said:

Electric Rain said:

I've been thinking about building this mechanically scanned video game system for a while now: **broken link removed** The thought just occurred to me, that I might be able to use laser diodes in place of LEDs. That way, the image could be projected on walls. Can I do this? Would the results be clear enough? Thanks.

Click to expand...

I think you probably have an exaggerated idea of what laser diodes can do?.

Click to expand...

Nigel, what do you mean? I'm pretty sure I've worked with a couple class 2 laser diodes in the past. They seem like they'd work just fine.

Electric Rain said:

Nigel Goodwin said:

Electric Rain said:

I've been thinking about building this mechanically scanned video game system for a while now: **broken link removed** The thought just occurred to me, that I might be able to use laser diodes in place of LEDs. That way, the image could be projected on walls. Can I do this? Would the results be clear enough? Thanks.

Click to expand...

I think you probably have an exaggerated idea of what laser diodes can do?.

Click to expand...

Nigel, what do you mean? I'm pretty sure I've worked with a couple class 2 laser diodes in the past. They seem like they'd work just fine.

Click to expand...

Basically just the amount of brightness available from laser diodes, it's pretty low for projecting a picture on to a wall - bear in mind that the dot you normally get will be spread out across the full width of the image. So a 1mm dot which looks fairly bright will be pretty dull spread across 1000mm - obviously only 0.1% as bright.

If you want to try it, I would suggest just using one diode as a test, and see if it's bright enough for you.

Oops! - double post :lol:

I saw a project that did just what you're talking about with one laser diode. It had a big spinning wheel. allong the edge of the wheel were a bunch of mirrors each tilted slightly from the one bofore. As the wheel spins the rotation draws a horizontal line. Each succesive mirror is tilted so the line is moved a small amount vertically. Using only one Laser diode would let you spend more money on that one diode to up the power.

bmcculla said:

I saw a project that did just what you're talking about with one laser diode. It had a big spinning wheel. allong the edge of the wheel were a bunch of mirrors each tilted slightly from the one bofore. As the wheel spins the rotation draws a horizontal line. Each succesive mirror is tilted so the line is moved a small amount vertically. Using only one Laser diode would let you spend more money on that one diode to up the power.

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I think a certain John Logi Baird has already done this stuff.