Bright Light Circuit

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Very Messy Example and Columbus 
--Sebastien Bailard 07:23, 10 September 2010 (UTC)

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Example Development

Release status: unknown

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Description laser cutter circuit
License GPL
Author Ian Daniher
Based-on Sui Generis
Categories Laser Cutter, Files Missing, Needs Parts List, Needs Build Instructions, Needs Render
CAD Models none
External Link none

Your-File-Name SOLID MODEL ASSEMBLY These are CAD files for the Solid Model Assembly, --Example User 12:00, Today's Date 20xx (UTC)
Your-File-Name CAD FILES FOR PARTS These are CAD files for each part., --Example User 12:00, Today's Date 20xx (UTC)
Your-File-Name EVEN MORE FILES These are are even more files., --Example User 12:00, Today's Date 20xx (UTC)|-
Your-File-Name SOLID MODEL ASSEMBLY This is the final finished machine N/A --Example User 12:00, Tomorrow's Date, 20xx (UTC)
Please edit this and click the links to put in your own files! --Sebastien Bailard 08:34, 10 September 2010 (UTC) 

Just to put the gist of it in writing: OPA569 as a high-current unity-gain buffer, driven by a DAC7571, with an ADS1113 to monitor the current-feedback from the OPA569. It'd provide sub-millivolt control with power feedback and PWM(via the current monitor and enable pin on the buffer, respectively.)

The whole toolhead would be directly controllable via a single I2C bus, or, with an added ATMEGA, via the same CAN bus as all other toolheads.

Any thoughts?

It's better to control laser diode current more-or-less directly, rather than indirectly through voltage control.

20 W and 40 W laser diode modules are becoming available at surprisingly low prices. A typical 40 W laser diode requires 2 V at 100 A (!). Merely 2.1 V will kill the module; so it seems a bit tricky to get enough power to the laser diode: 100 A * 2 V gives 200 W of input electrical power. Even more tricky is getting rid of the 160 W of waste heat that remains after 40 W of optical power comes out. A heatsink that can handle 160 W of heat energy seems like it will be far too heavy to mount on a moving RepRap tool head -- is there a better way?

Are there any real advantages to spending time and energy designing and building a new custom "laser diode driver" electronics rather than buying one off-the-shelf? [1]

Bill of Materials/Parts List

More Examples

Further reading

  • Laser Cutter Notes
  • SLS Printer: might be able make a single machine and a single tool head both (a) do laser sintering when aimed at a powder bed, and (b) do laser cutting when aimed at a sheet of acrylic, etc.
  • Protospace wiki: OpenSource Laser Cutter driver project [2]
  • The Lasersaur Project, an open-source laser cutter[3]
  • RepRap: Builders blog: "selective laser sintering part 8: reciprocating laser cutter"[4] uses a 1 Watt IR laser diode, and successfully cut some flat black plastic about 1mm thick at around one inch per minute, and 3mm mdf at the rate of about 1cm / 3 minutes.
    • Is it possible to get *visible* (and hence safer and easier to align than IR) laser diodes at high power (at least 250 mW, preferably closer to 20 W) and reasonable cost?