Non-contact temperature measurement with optical pyrometers and FLIR thermal imagers is vulnerable to field-of-view (FOV) size-of-source effects and emissivity mismatch.
1. Emissivity and Cavity Geometry
Industrial blackbody calibrators such as the DB Pyrovia Series (50C to 400C) utilize a 57mm aperture precision machined target coated with ultra-high emissivity black ceramic to simulate an ideal Planckian blackbody radiator.
2. Size-of-Source Effect (SSE) Elimination
Ensure the blackbody target diameter is at least 1.5 times greater than the spot size calculated from the optical distance-to-spot ratio of the sensor under test.