SystemPlus Publishes FLIR Lepton Reverse Engineering

SystemPlus Consulting publishes FLIR Lepton thermal imaging module reverse engineering report. 60 x 80 micro-bolometric array-based Lepton is used in FLIR One low cost iPhone clip-on camera and in Norwegian PD-100 micro UAV (thanks to SO for the info!). SystemPlus' report says:

"The microbolometer array is grown monolithically on top of a readout integrated circuit (ROIC) to comprise the complete focal plane array (FPA). An anti­reflection (AR) coated window is bonded above the sensor array via a wafer­level packaging (WLP) process, encapsulating the array in a vacuum. The purpose of the vacuum is to provide high thermal resistance between the microbolometer elements and the ROIC substrate, allowing for maximum temperature change in response to incident radiation.

The system electronics that receive and process the signal are a custom application­ specific integrated circuit (ASIC) device mounted in flip­chip on the substrate. Digital Optics' WLO brings an important part of the cost reduction. The silicon lenses are made at the wafer level with lithography and etching processes. The final cost reduction comes from the core housing, which is a three­dimensional molded interconnected device (3D­MID). Incorporating a conductive circuit pattern inside the housing provides grounding and allows FLIR to integrate a temperature sensor. Thanks to its strong integration at the core level with innovative WLO, wafer­level packaging (WLP) and custom ASIC use, the FLIR Lepton is the world's smallest microbolometer­based thermal imaging camera core."

(Source: LEPTON Infrared Camera Module Report, Dec. 2014,
System Plus Consulting