FLIR Lep to n w ith Rad io me try Quic kstart Gu ide Document Number: 102-PS245-76 Rev 100 Table of Contents Revision History ............................................................................................................................................... 1 Scope ..................................................................................................................................................................... 1 Compensation for Final System Integration............................................................................................... 2 Background ........................................................................................................................................................ 2 Application.......................................................................................................................................................... 2 Requirements ............................................................................................................................................... 2 Procedure ....................................................................................................................................................... 3 Revision History Version Date Comments 100 December 8, Initial Release 2016 Scope This document describes a simplified subset of the parameter updates necessary for integrating the Lepton with Radiometry configuration (80x60 part number: 500-0763-01) into a final system. For a more in depth discussion of the radiometry background principles and sources of error, please refer to the Advanced Radiometry Application Note (document number 102- PS245-75). Information on this page is subject to change without notice. 102-PS245-76, Lepton with Radiometry Quickstart Guide, Rev:100 p. 1 FLIR Lep to n w ith Rad io me try Quic kstart Gu ide Compensation for Final System Integration Background The Lepton with Radiometry is calibrated at the factory for accurate measurement of a scene with 100% emissivity in close proximity to the camera. Factors such as scene emissivity and unwanted signal from sources other than the scene will influence the measurement accuracy of a real scene. Compensation for the factors that enter as a result of integrating the Lepton in a complete system is the subject of this document. The Lepton with Radiometry calibrated values and parameter defaults assume no window or 100% window transmission, but typical systems in which the Lepton is integrated include a window which needs to be characterized to achieve accurate radiometry. The window must be transmissive in the long wave infrared (LWIR) band, specifically 7-14microns. Typical materials include Ge, ZnS, and Si where the average transmission across the LWIR band would be provided by the window supplier or preferably characterized for best accuracy as described in the subsequent section. The temperature of the window should also be characterized to determine the additional irradiance it adds to the system. In use, the window temperature will vary as a function of the environment temperature which can be compensated for by either run-time measurement (i.e. including a temperature sensor) or simply characterizing the value at a particular temperature and relating it to the temperature sensors included in the Lepton module. For best radiometric accuracy, it is recommended that instead of utilizing the transmission values provided by the supplier, that the window transmission and window temperature are characterized on a small sample set in the final system to be applied to all systems using the same configuration. The window transmission should be characterized first, then the window temperature at a single ambient temperature point at a minimum. Note that the window temperature measurement error is high when the window transmission is very high, but in this case the impact of this parameter is lower. The following section discusses the procedure for characterizing the window parameters which are effectively correcting all gain (e.g. window transmission) and offset (e.g. reflection and/or irradiance from the window) errors in the final system. Application Requirements Two black body sources with known temperatures and emissivity, e.g. 20C and 60C Software interface to communicate with Lepton over i2c Information on this page is subject to change without notice. 102-PS245-76, Lepton with Radiometry Quickstart Guide, Rev:100 p. 2