Open Source Hardware Cost-Effective Imaging Sensors for High-Throughput Droplet Microfluidic Systems

Microfluidic systems have been and continue to be very attractive to scientific community. In a typical droplet microfluidic measurement setup, a microscope and a camera attached to it are used for observing the droplets. The throughput of droplets has increased over time, and high-throughput systems require sensors with high framerates per second. With the increase of the required speed, also the price of the cameras increases. To avoid the use of expensive cameras, many unusual cameras such as webcams and smartphone cameras have found their way to droplet microfluidics. Additionally, the droplet microfluidic systems tend to grow more complex and autonomous and need more customization than the closed hardware can provide. This leads to the need for highly customisable, cost-effective, and open-source hardware. In this article, we compare three cost-effective imaging sensors, two of them open-hardware, that could be considered to be used in high-throughput droplet microfluidic systems. During the tests two different entry-level open-source systems based on Raspberry Pi were tested and the results compared to slightly more expensive mid-range Basler camera results. The entry-level systems were able to reach 200 and 665 frames per second and the mid-range comparison reference to 750 fps.