Thermography Equation: From Conceptual Relation to Quantitative Formulation via the Optogeometric Factor

TL;DR

This paper develops a quantitative thermography equation by deriving the optogeometric factor, linking radiant flux to camera pixel energy through geometric optical relations, enabling more precise thermal measurements.

Contribution

It introduces a general framework for quantitative thermography based on the optogeometric factor, bridging conceptual and mathematical formulations.

Findings

Derived a new thermography equation using the optogeometric factor

Applicable to both scene-based and sensor-based thermography

Provides a unified framework for quantitative thermal imaging

Abstract

This article presents a methodological transition from the conceptually formulated thermographic measurement equation (the so called thermography equation) to its quantitative form, expressed through the optogeometric factor. This factor directly links the known radiant flux from the measured surface to the energy captured by a single pixel of a thermal camera. The formulation is based on geometric optical relations between the scene and the detector and is applicable to both scene-based and sensor-based approaches. The resulting expression provides a general framework for quantitative thermography.