Laser projector

http://shakirfm.googlepages.com/home
Featured on HAck A day! http://hackaday.com/2008/09/23/laser-led-pov-projector/
Final year project - ECE-' 08 Atria Institute of Technology(Shakir, Vrandesh & Shrikant) and BMSIT( Aditya) Uses red keychain pointer lasers and a continuously rotating polygonal mirror to form characters on a surface. Motor is a PC cooling fan- dynamic speed control using PWM . Uses an Atmel 8052 microcontroller and currently accepts a maximum of 70 ASCII characters. Also features an extensive UI via the serial port on hyperterminal in windows, where you can change scroll speed, character size and number of characters to display, on the fly. Feel free to contact me at- shakirfm[AT]gmail[DOT]com if you'd like to know more

Category:

Science & Technology

Tags:

• laser
• projector
• text
• rotating
• mirror
• pointer
• lasers
• display
• DIY
• electronics
• gadget

[vdub350]

I don't understand how you got the timing working... it seems as though DC motors are unreliable at keeping constant speeds.

[shakirfm]

The DC motor's speed is controlled by PWM. You need to experiment around with different frequencies. Timing, if you can call it that,is taken care of by the IR led and detector setup actually. The lasers trigger when the IR beam is blocked so you don't really need to do any synchronization

[MrWampus]

This makes me happy that I chose EE, very inspiring. Thanks!! Very cool project!

[shakirfm]

@MrWampus: Thank you. Your comment made my day :-)

@rwert41: Thanks :)

@mamamaster2: I have absolutely no idea, sorry. Some generic trance mp3 I discovered on my hard disk a long time ago

[shakirfm]

well, a fan motor is quite efficient and dirt cheap. no contacts, no friction. and they are designed to run continuously practically for ever. you'll be surprised at how torquey these things are actually.another good thing is that they give u a large rotating platform on which to mount the mirror, as long as you can center the thing(tricky)

i used acrylic mirrors- they weigh next to nothing. and the hexagonal former is a hollowed out aluminium hex bar turned on a lathe.

[shakirfm]

well, its about 1800 rpm. i tried something along those lines too initially- i tried using a cd rom drive motor but settled for a cooling fan in the end.. let me know how your project shapes up! i'd be very interested to know :)

[qwert41]

nice work :)

[hellsmaw84]

heres a great task for ya. make the digits display near multi color using 5 green lasers as well as the 5 red. should be interesting!

[youngnewtonian]

GREAT work!

[mamamaster2]

name of the song

[hapoo82]

Whats the reason you went with fan motors instead of cd rom motors?

The device I'm spinning is probably going to be pretty heavy so i need a strong motor, I'm not sure a fan would cut it.