Teledyne Teledyne FLIR Lepton 3.1R Thermal Camera Module, 160x120 LWIR Radiometric

The Lepton 3.1R's SPI interface is compatible with a wide range of microcontrollers, including ESP32, STM32, Arduino boards (via SPI library), Raspberry Pi (using SPI GPIO), and other MCUs with a standard 4-wire SPI master. You will need to implement the specific communication protocol and clock polarity as defined in the Teledyne FLIR Lepton Software Interface Description document to correctly read image frames and telemetry data.

The Lepton 3.1R provides radiometric data, meaning each pixel's value corresponds to a temperature. After establishing SPI communication, you read the 14-bit data words for each pixel. These raw values must then be processed using calibration constants (stored in the module's RAM) and a linear equation to convert to temperature in Celsius or Kelvin. Teledyne FLIR provides SDKs and application notes with example code for performing this conversion on various platforms.

The Lepton 3.1R typically operates from a 2.8V input for the core and I/O. Detailed power sequencing and current draw specifications are in the datasheet. Expect an operating current in the range of several hundred milliamps during active imaging, with specific sleep or low-power modes available to reduce consumption for battery-operated IoT deployments. Always use a stable, low-noise LDO regulator to power the module for optimal image quality.

While the Lepton 3.1R sensor module itself is industrial-grade, it requires proper environmental sealing and a protective window (made of material transparent to LWIR, like germanium) for outdoor or harsh environment use. The sensor is sensitive to moisture and physical damage. For field deployment, it must be housed in an enclosure that maintains the sensor within its specified operating temperature range and protects it from condensation, dust, and mechanical shock.