FLIR
LEPTON® Engineering Datasheet
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and therefore, not subject to EAR. NSR (6/14/2018).
Information on this page is subject to change without notice.
Lepton Engineering Datasheet, Document Number: 500-0659-00-09 Rev: 203
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as fixed-mount applications, scene-based NUC is less effective. In stationary applications and those which need
highest quality or quickly available video, it is recommended to periodically perform a flat-field correction (FFC).
FFC is a process whereby the NUC terms applied by the camera's signal processing engine are automatically
recalibrated to produce the most optimal image quality. The sensor is briefly exposed to a uniform thermal scene,
and the camera updates the NUC terms to ensure uniform output. The entire FFC process takes less than a
second.
Figure 7 - Examples of Good Uniformity, Graininess, and Blotchiness
Lepton provides three different FFC modes:
•
External (default for shutter-less configurations)
•
Manual
•
Automatic (default for configurations with shutter)
In external FFC mode, FFC is only executed upon command, and it should only be commanded when the camera
is imaging an external uniform source of a known temperature. To ensure radiometric accuracy in this mode, the
user must explicitly update the radiometry shutter mode to "User" and input the temperature of the scene during
FFC via the CCI. If in imaging mode only and temperature measurement is not required (radiometry disabled), any
uniform source such as a uniform wall will suffice.
Manual FFC mode is also executed only upon command, except that when FFC is commanded, Lepton closes its
integral shutter throughout the process. Note that it is not necessary to ensure a uniform external scene of a
known temperature before commanding FFC in manual FFC mode because the shutter serves as the uniform
source and includes a temperature sensor with automatic input for radiometric measurements.
