NanoDlp and the topic of Masks - Part 3 - Assembly and Operation

Click for Article

The voltage divider circuit this project uses is shown here.  R1 is the photoresistor.  R2 is the 10k resistor.  Vin is the battery which in my case is a 1.5v AA battery.  Vout is the volt ohm meter.  In the next picture you can see the assembled circuit.

The next picture shows the completed circuit based on an Arduino Uno.  The 10k resistor bridges Ground and Analog Pin 3.  One end of the photoresistor goes to the 5v power pin.  The other end goes into Analog Pin 3 with the 10k resistor.

The sketch for the Arduino Uno is here.  It will output (to the serial pins) an analog voltage reading every second that is an average of twenty readings for that second.  A quality metric will also be output where you would like to see a reading of 1.5 or less indicating that the input was stable.

Finally, a first attempt to use the "hopefully good enough" meter!  I have gone into the NanoDlp Mask Generation Wizard and changed the build area dimensions to 10 and 5 and the measurement point dimensions to 200.  From here it is up to you as I am still working on my spreadsheet that I hope will simplify a slightly painful process from this point.

You need to measure the output of the cells displayed on the print surface while adjusting the mask values shown by the wizard.  I would recommend that you start by ignoring the outer two rows and columns as that will shorten your task AND also shorten the additional exposure time that would be needed if you included them.

Your mission is to adjust the cells such that they all project the same amount of light with the ones on the outside starting at 255 and going down with the ones in the center being somewhat lower than that and going up as you move out from the center.

This is a painful process!  This is why I am working on a spreadsheet to help take some of the pain away.  Unfortunately it is frustrating me at the moment as the results of the mask, when I measure light output, is not as I expect it to be!