fullseye

tcspc_simulate — PHOTON tcspc op

• データ種: なし → counts(引数だけで決まる op —— 画像やデータの入力を取らない)
• 呼び出し: import fullseye as fs; fs.ledger.tcspc_simulate(distance_m=3.0, bins=256, bin_ps=100.0, signal_photons=50.0, ambient_photons=20.0, irf_fwhm_ps=200.0, seed=0, noise=True) (実装を直接呼ぶなら import photoncount; photoncount.tcspc_simulate(distance_m=3.0, bins=256, bin_ps=100.0, signal_photons=50.0, ambient_photons=20.0, irf_fwhm_ps=200.0, seed=0, noise=True)、台帳から引くなら opsphoton.get("tcspc_simulate"))

使い方

Synthesise a single-pixel photon arrival-time histogram with a known answer.

The generative model of a direct time-of-flight (dToF) / TCSPC measurement::

lambda_k = signal_photons * P(pulse in bin k) + ambient_photons / bins
N_k      ~ Poisson(lambda_k)

where the pulse is a Gaussian of full width at half maximum irf_fwhm_ps centred at the round-trip time t0 = 2*distance_m/c, and P(pulse in bin k) is its exact integral over the bin (an erf difference, not a midpoint sample) — so with noise=False the returned histogram is an analytic ground truth, not an approximation of one. ambient_photons is the total background (sunlight, dark counts) spread uniformly over the window.

noise=False returns lambda_k itself (no sampling); noise=True draws one Poisson realisation from numpy.random.default_rng(seed).

Returns a float64 1-D histogram of length bins. The unambiguous range is c * bins * bin_ps / 2 — 3.84 m at the defaults (256 bins x 100 ps), with a bin resolution of 1.50 cm.

The pulse is not renormalised to the window: a target near the far edge genuinely loses the tail of its pulse, exactly as a real sensor does, and the total signal comes back slightly below signal_photons. Renormalising would have made the truncated pulse asymmetric and biased its centroid.

Raises ValueError: a non-positive distance_m, a bins outside [2, MAX_BINS], a non-positive bin_ps / irf_fwhm_ps, negative photon budgets, a non-integer or negative seed, a non-bool noise, and — instead of wrapping the pulse silently to a short distance — a distance_m whose round-trip time falls outside the bins * bin_ps window.

詳しい使い方ガイド

• photon_timeresolved ファミリ ガイド

参考(サンプルデータ・文献)

• サンプルデータ カタログ(DL URL / ライセンス) — 2-D は skimage.data(BSD/public)+ 合成、3-D は実データ源(Stanford/PDS 等)の DL URL。
• 演算子の来歴・参考文献 — この op 族の元になった研究/手法の出典。
• アルゴリズムの正典(著者・年)と用途は上記ファミリ使い方ガイドに記載。

実行できる例(この op を実際に呼ぶ検証済みサンプル)

• photon_timeresolved — py -3.11 examples/photon_timeresolved.py
• poc_dtof_ranging — py -3.11 examples/poc_dtof_ranging.py

型が繋がる次の op(counts を入力に取れる)

tcspc_coates_correct · tcspc_irf_convolve · tcspc_background_subtract · tcspc_stats · dtof_depth · lifetime_fit · lifetime_phasor

同カテゴリ(tcspc)

tcspc_irf_convolve · tcspc_background_subtract · tcspc_stats

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Provenance: photoncount.py — PHOTON operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.

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