Critical Design Review
Blake Ipson
John Chen
Matt Graeff
Steven Benedict
Weston Welge
Team PhotoCon
EXPO Lab
Department of Electrical, Computer, and Energy Engineering
University of Colorado at Boulder
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Matt
Prototype a fast lithography system accurate
to 15μm
Drive galvanometer mirrors to draw 2D
images within a 3.5mm scanning area
Coordinate laser power modulation based on
input vectors
Stand-alone, modular and “transportable”
Laser
Diode/Power
Supply
Collimation
From
Lens
Galvo X
Doublet
Lens
Galvo Y
Laser
~ 4% Power Tap
Power
Detection
Servo
Drivers X/Y
ADC
DAC
External
Memory
Camera
DAC
MCU
From
PC
Demonstration Only
PC
Matt
John
John
X Galvo
Y Galvo
4
Channel
ADC
4
Channel
ADC
I2C
I2C/Parallel
PC
RS-232
Atmel 32bit AVR
UC3C0512
1
Channel
DAC
1
Channel
DAC
X Galvo
Y Galvo
Laser Driver
Power Meter
1
Channel
ADC
Steven
SPI
EEPROM
1
Channel
DAC
Module
Inputs
Outputs
Functionality
OH_SHIT_STOP
N/A
error LED on
Turn on error LED
Call lsr_off()
send_vec(GALVO_CENTER)
Module
Inputs
Load
User options
Vector file
Write constants, vectorfile
Check
lsr_pwr_on=int,
lsr_pwr_off=int,
draw_method=”dots”,
galvo_center=int,int,int
If no,
call OH_SHIT_STOP
If yes,
write LSR_SCALE_ON,
write LSR_SCALE_OFF,
write DRAW_METHOD,
write GALVO_CENTER)
load vector file to flash mem
call run()
Outputs
Functionality
Steven
Module
Inputs
Outputs
Functionality
Run
Drawing method constant
call function or error
If(DRAW_METHOD=”dots”)
Draw_dots()
Else
if(DRAW_METHOD=”lines”)
Draw_lines()
Else
OH_SHIT_STOP
Module
Inputs
Outputs
Functionality
Draw_dots
Vectorfile
function call(s)
Loop(lines in vector file)
Parse line  x,y,z
Send_vec(x,y,z)
If(error<defined)
Lsr_on()
Detect_energy()
Lsr_off()
Set_pwr()
Break
Break
Module
Inputs
Outputs
Functionality
Module
Inputs
Outputs
Functionality
Lsr_on
N/A
DAC value
Read lsr_pwr_on
Write to DAC
Module
Inputs
Outputs
Functionality
Module
Inputs
Outputs
Functionality
Send_vec
Int x,y,z
DAC value
Write x to x-galvo
Write y to y-galvo
Write z to z-galvo
Module
Inputs
Outputs
Functionality
Steven
Lsr_off
N/A
DAC value
Read lsr_pwr_off
Write to DAC
Detect_energy
N/A
Energy
Energy=0
Loop n
X=read power from sensor
Energy=Energy+x
Return energy
Set_pwr
Energy
Lsr_pwr_on
Calculate power from energy over
time t=n
Lsr_pwr_on=result
If lsr_pwr_on>LSR_SCALE_ON
Call OH_SHIT_STOP
Weston
Weston
Component
Status
Laser Diode
In place
Laser Power Supply
In place
Galvo Scanner
In place
Galvo Servo drivers
In place
Collimating Lens
In place
Objective lens
In place
Miscellaneous Optics
Acquired
Optics Breadboard
In place
CMOS camera
Not here
Microcontroller
Acquired
Power Supply
In place
PCB and components
Acquired
Task
Blake
John
Matt
Optics
X
X
X
Laser diode
X
X
Collimation
X
X
Galvanometer
Scanning Lens
X
X
X
Interface
X
X
X
X
Power Supply
PC interface
Documentation
Weston
X
X
X
X
Microcontroller PCB layout
MATLAB Pre-processing
Weston
X
Camera/Polymer
Electronics
Steven
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
•Milestone 1
• Using the Microcontroller
Development board or STK600
• Laser Modulation
• Rudimentary Galvo Movements
using on-board flash
• Oh_shit_stop!
• Optics in place, calibration
procedure solidified
• Schematic Completed
• Rudimentary layout finished
Blake
•Milestone 2
• Microcontroller Unit
• Drawing Functionality
• RS232 Interface
(Debugging/Working)
• C Code on PC (UI Code) Finished
• PCB Revision 1 completed and being
debugged
• Revision 1 of User Manual complete
Blake
•Expo
• User Manual Fully Complete
• PC Interaction
• Will accept vector files
• Draw shapes with dots
• Timed to complete per refresh of
CMOS camera
• System calibrated
Blake
Blake