TL;DR
Katie Dumont created a DIY handheld thermal camera using an Arduino UNO R4 Minima board and a Seeed Studio MLX90640 thermal imaging sensor. The MLX90640 features a 32×24 pixel grid that detects infrared radiation, allowing the camera to visualize temperature differences. Dumont utilized the I2C interface to transmit data from the sensor to the Arduino, which processes this data to generate thermal images.