UV Reflectometer using ARDUINO NANO and SCILAB

UV-Reflectometer which is designed to characterize materials and coatings used for the construction of UV-C sterilization chambers to maximize UV exposure and hence object sterilization efficiency. It scans the UV intensity reflected from sample panels consisting of or coated with the material to be characterized. Sample panels having a standardized size (70*100 mm = "hull cell panels"). The radiation from the UV-C source is reflected directly and indirectly by two sample panels and the reflection intensity is measured by a Schottky photodiode tilted over a range of 0 to 200 degerees covering a representative positioning of a sample object within the walls of a chamber constructed from the material to be characterized. Tilting of the photodiode is done by a stepper motor with the lower end-position controlled by an end-stop micro-switch. The stepper motor uses a stepper driver board. Levers hold the sample panels in place and the position of the levers is controlled by two micro-switches, making sure that the UV source will only be switched on with the openings of the chamber covered. While the Schottky photodiode has already an amplifier circuit attached to it on the used break-out board, an additional 10x amplification is provided by an external OP. The stepper motor driver board, relais for UV source, panel micro-switches, end-stop microswitch and OP output signal are connected to an ARDUINO NANO microprocessor. The control of the reflectometer via USB, data acquisition, processing and storage is realized by a program using the open source SCILAB environment. The physical device consists mostly of 3D printed elements designed in TINKERCAD (

https://www.tinkercad.com/things/4fHqMrWtHtj

). All stl files were published under

https://www.thingiverse.com/thing:4703117

. Full documentation of the design under

https://github.com/wojczy/UV-Reflectometer