Difference between revisions of "Flameman/pcb-laser-exposer"

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(pcb laser exposer)
(project idea)
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== project idea ==
 
== project idea ==
 
The polygon mirror assembly is mounted vertically on the flatbed scanners sled. The flatbed scanner sled is the Vertical axis, and the polygon mirror defelcting the laser in the scanner is the horizonbtal axis. Each Horizontal line is scanned about 150 times before the sled moves on to the next vertical position. The laser is scanned by the mirror continuasly at 55 Revolutions of the mirror per second, or 333 Hz scanrate, as the mirror is hexagon shaped. The exposure pattern is produced by turning the laser on and of synced to the rotation of the mirror.
 
  
 
* [http://www.das-labor.org/wiki/LaserExposer avr idea]
 
* [http://www.das-labor.org/wiki/LaserExposer avr idea]
 
* [http://www.youtube.com/watch?v=fi4P-Bwc6g8&feature=player_embedded video]
 
* [http://www.youtube.com/watch?v=fi4P-Bwc6g8&feature=player_embedded video]
  
 +
=== polygon mirror ===
 +
 +
Its assembly is mounted vertically on the flatbed scanners sled. The flatbed scanner sled is the Vertical axis, and the polygon mirror defelcting the laser in the scanner is the horizonbtal axis. Each Horizontal line is scanned about 150 times before the sled moves on to the next vertical position. The laser is scanned by the mirror continuasly at 55 Revolutions of the mirror per second, or 333 Hz scanrate, as the mirror is hexagon shaped. The exposure pattern is produced by turning the laser on and of synced to the rotation of the mirror.
 +
 +
 +
=== Optics & Optical Issues ===
 +
 +
The original laser in a laserprinter is infrared, and that wavelength doesn't work for exposing pcbs which need 405nm at least.
 +
 +
You'd removed the infrared laser, and make a nice alluminium laser mount milling down the mirror assembly to fit it. As the lenses in the polygon mirror assembly had the wrong optical properties for my application, csudr different wavelength and different focussing distance, you'd removed them all.
 +
 +
The optical system should consists only of the laser, its focussing lens, and the polygon mirror.
 +
 +
There is one problem with this: as the beam length varies with the angle of the deflected laser beam, the focus of the laser lens would also have to be adjusted for each beam length. As this isn't done, the laser gets blurry at the ends and the middle of the scanline. But this is not a problem in practice, as the image gets sharp enough.
  
 
== how does laser beam work ==
 
== how does laser beam work ==

Revision as of 17:18, 8 April 2012

For more interesting projects done by Flameman and Legacy, be sure to check out his project index


pcb laser exposer

project idea

polygon mirror

Its assembly is mounted vertically on the flatbed scanners sled. The flatbed scanner sled is the Vertical axis, and the polygon mirror defelcting the laser in the scanner is the horizonbtal axis. Each Horizontal line is scanned about 150 times before the sled moves on to the next vertical position. The laser is scanned by the mirror continuasly at 55 Revolutions of the mirror per second, or 333 Hz scanrate, as the mirror is hexagon shaped. The exposure pattern is produced by turning the laser on and of synced to the rotation of the mirror.


Optics & Optical Issues

The original laser in a laserprinter is infrared, and that wavelength doesn't work for exposing pcbs which need 405nm at least.

You'd removed the infrared laser, and make a nice alluminium laser mount milling down the mirror assembly to fit it. As the lenses in the polygon mirror assembly had the wrong optical properties for my application, csudr different wavelength and different focussing distance, you'd removed them all.

The optical system should consists only of the laser, its focussing lens, and the polygon mirror.

There is one problem with this: as the beam length varies with the angle of the deflected laser beam, the focus of the laser lens would also have to be adjusted for each beam length. As this isn't done, the laser gets blurry at the ends and the middle of the scanline. But this is not a problem in practice, as the image gets sharp enough.

how does laser beam work

Pcb-laser-exposer-idea.gif

beam idea from Panasonic KX P4410

Pcb-laser-exposer-beam.jpg


where to buy (proof list)

laser @ 405nm ??

  • Lilly-Electronics on ebay
  • o-like

Canon LBP1210

laser

mirror motor



             M63154AFP
     3-phase Brushless driver
           ______________
      VCC |1    \__/   36| nc    
      RS  |2           35| Limit
      FLT |3           34| Vref
      B1  |4           33| Vctl
      PS  |5         * 32| /Acc   <-----
phase.U   |6         * 31| /Dec   <-----
pahse.V   |7           30| RCP
      Gnd |8           29| Gnd 
      Gnd |9           28| Gnd
      Gnd |10          27| Gnd 
      Gnd |11          26| Gnd
phase.W   |12          25| SGnd
      HU+ |13          24| OSCV
      HU- |14          23| OSCC
      HV+ |15          22| FG-
      HV- |16          21| FG+ 
      HW+ |17          20| Amp.out 
      HW- |18          19| FGout 
          |______________|



                 output current 
ACC   DEC        VCTL(CPout)       Function
------------------------------------------------
H(5V) H(5V)         0uA            Hold
H(5V) L(0V)      -200uA            Deceleration
L(0V) H(5V)      +200uA            Acceleration
L(0V) L(0V)         0uA            Hold



Cable  Pin    Symbol       Function
---------------------------------------------------------------------
         1    Vcc          Power supply 
         2    RS           Current sense 
         3    FLT          Connect to application of filter 
         4    B1           Short brake switch 
         5    PS           Power save signal input 
         6    U            Motor phase U output 
         7    V            Motor phase V output 
       8..11  Gnd          Power Gnd 
        12    W            Motor phase W output 
        13    Hu+          Hall sensor signal input (U phase +)
        14    Hu-          Hall sensor signal input (U phase -)
        15    Hv+          Hall sensor signal input (V phase +)
        16    Hv-          Hall sensor signal input (V phase -)
        17    Hw+          Hall sensor signal input (W phase +)
        18    Hw-          Hall sensor signal input (W phase
        19    FGout        FG comparator output
        20    Amp.out      FG amp. output
        21    FG+ FG       signal input (+)
        22    FG-          FG signal input (-)
        23    OSCC OFF     Timer setup -1
        24    OSCV OFF     Timer setup -2
        25    SGnd         Gnd
      26..29  Gnd          Power Gnd
        30    RCP          Charge pump output current setup term.
        31    DEC          Deceleration signal input
        32    ACC          Acceleration signal input
        33    VCTL         Motor speed control voltage input
        34    VREF         Reference voltage input
        35    LIMIT        Current limit set up terminal
        36    N.C.         N.C