Design and implementation of an arduino-based central electronic board for event-driven microscopy

Abstract

For (single-molecule) fluorescence microscopy techniques, central electronic boards are typically used to orchestrate various instruments via analog and digital signals. Often procured from companies providing proprietary software, these boards can manage tasks and controls in sub-microseconds, as exemplified by costly FPGA (fieldprogrammable gate array) boards. However, Arduino-based microcontroller opensource solutions are gaining popularity due to their cost-effectiveness and more straightforward programming despite operating "just" in the millisecond range with sequential control. This project aimed to design and optimize the use of an Arduino-based control board. A comparable level of speed and precision was achieved by utilizing a Teensy microcontroller with 50 Ω load buffered digital outputs and a dedicated digital to analog converter with actively filtered and buffered analog outputs. The digital outputs also offer a time resolution in the microsecond range. The analog outputs operate within a -10 V/+10 V range, offering 16-bit resolution with a rise time between 0.5 μs and 7 μs. An advancement to previous Arduino-based solutions is the simultaneous switching of multiple channels rather than a rapid sequential approach. This has been made possible by leveraging the capability of the microcontroller to update multiple register values concurrently. Additionally, a controller software was developed that, in conjunction with μManager, facilitates the creation and application of complex signal patterns.The development of a new central electronic board contributes to the evolution of costeffective and efficient control systems in microscopy. The underlying idea is to establish a platform for event-driven microscopy, which reacts to an event by image analysis with modified measurement parameters without a significant time delay. The microcontroller approach allows the use of "unlimited" memory for any measurement protocol and convinces with configurability and flexibility.