LCD Mask/Light Metering Tool for 5.5" Resin Printers (Anycubic Photon, EPAX X1, Elegoo Mars, etc).

thingiverse

Some LCD-based resin printers have uneven light distribution across the screen, due to the way the LED light source is placed underneath, manufacturer's design of the LED array, etc. Some firmwares for these printers have a function that allows you to define a mask that slightly dims the brighter areas of the screen in order to give a more uniform illumination and hopefully enable more consistent dimensional accuracy across the build plate. This thing consists of a grid that installs in place of the vat, dividing the screen into 66 10mm x 10mm sectors, and a holder for a light-dependent resistor (LDR) that fits into each grid position. This allows you to make an accurate map of your screen illumination that can be converted into a mask with [software tools](https://github.com/Photonsters/MaskMappingTools) under development at [photonsters.org](http://photonsters.org). Also included are two .photon files that illuminate the entire screen for 10x 30-second intervals, allowing you adequate time to make all the measurements. One is all-white (LCD off) and one is all-black (LCD fully on).