arXiv subjects

Jan Sova

Publications and source records attributed to Jan Sova.

3 recordsLinked to original sources

arXiv2025

From \'Etendue to the Lowest Fundamental SNR: Pixel \'Etendue (Optogeometric Factor) Interpreted as Mode Count

The optogeometric factor, recently introduced as a pixel level form of \'etendue, quantifies the spatial angular throughput of a detector element. In this work its interpretation is extended by identifying optogeometric factor with the number of accessible optical modes per pixel. This mode based perspective establishes a direct link between radiometric throughput and quantum photon statistics. By combining optogeometric factor with the Bose Einstein distribution, an estimate of the lowest achievable signal to noise ratio (SNR) at the pixel level is derived. Explicit formulas are presented in both scene-based and sensor based forms, showing how the minimal SNR depends on aperture geometry, pixel pitch, f-number, wavelength, and source temperature. This formulation provides a compact and physically transparent benchmark for evaluating imaging sensors against the lowest expected quantum noise limit.

quant-ph↗

arXiv2025

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

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.

physics.optics↗

arXiv2025

Instrument-limited pixel-level SNR bounds from optical throughput

The radiometric integral is the fundamental radiance--to--flux relation in imaging, whereas \'etendue is typically used as a compact system-level descriptor. For quantitative imaging and calibration, however, the operative mapping must be explicit at the level of individual detector pixels, including pixel acceptance and field-dependent pupil visibility. This work packages the pixel-restricted radiometric integral into a reusable geometric throughput factor by defining a per-pixel optogeometric (optical-throughput) factor $F_{\mathrm{opg},i}$ (units \si{m^2.sr}) such that, under weak radiance variation, $\Phi_i \approx L_i\,F_{\mathrm{opg},i}$. Making throughput explicit at the pixel scale yields an optics-delivered photon budget in which the incident photon count at the detector, $N_{\mathrm{inc},i}$ (before quantum efficiency), scales linearly with geometry: $N_{\mathrm{inc},i}\propto F_{\mathrm{opg},i}$ for a given scene radiance distribution and fixed acquisition settings (bandwidth, integration time, and optical transmission). The corresponding optics-delivered (pre-detection) shot-noise ceiling is set by the incident photon count $N_{\mathrm{inc},i}$, with $\mathrm{SNR}_{\mathrm{inc},i}\le \sqrt{N_{\mathrm{inc},i}}\propto \sqrt{F_{\mathrm{opg},i}}$, while in photoelectron units one has $\mathrm{SNR}_i \le \sqrt{N_{\mathrm{ph},i}}=\sqrt{\eta(\bar\nu)\,N_{\mathrm{inc},i}}\propto \sqrt{F_{\mathrm{opg},i}}$, where $N_{\mathrm{ph},i}$ is the detected photoelectron count and $\eta(\bar\nu)$ is the (narrowband) quantum efficiency; additional detector/electronics noise sources (e.g.\ dark current and read noise) can only reduce the achieved SNR below these shot-noise limits.

physics.optics↗