fullseye

csi_signal_simulate — INTERFEROMETRY `simulate` op

データ種: なし → sweep(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.csi_signal_simulate(surface_um=6.0, z_start_um=0.0, z_step_um=0.05, n_planes=241, wavelength_um=0.6, envelope_fwhm_um=2.8, envelope_sigma_um=None, bias=0.5, amplitude=0.4, reflectivity=1.0, noise=0.0, seed=0) (実装を直接呼ぶなら import interferometry; interferometry.csi_signal_simulate(surface_um=6.0, z_start_um=0.0, z_step_um=0.05, n_planes=241, wavelength_um=0.6, envelope_fwhm_um=2.8, envelope_sigma_um=None, bias=0.5, amplitude=0.4, reflectivity=1.0, noise=0.0, seed=0)、台帳から引くなら opsinterferometry.get("csi_signal_simulate"))

使い方

Synthesise the z-scan interferogram of one pixel over a known surface height.

The coherence-scanning forward model, and the reason every other operator here has an exact answer to be checked against::

I(z) = bias + amplitude*reflectivity * exp(-(z-z0)^2 / 2 sigma^2)
                                     * cos(4*pi*(z-z0)/wavelength)

with z0 = surface_um. The 4 is the double pass — light goes down to the surface and back, so one fringe is wavelength/2 of height, not a whole wavelength. Getting that factor wrong is a clean 2x in every height this module produces, which is why it is written out here rather than hidden in a constant.

surface_um: the true surface height z0, in the scan’s own coordinate. Need not land on a scan plane — the sub-step case is the interesting one and the tests use it deliberately. z_start_um/z_step_um/n_planes: the scan grid, z_k = z_start_um + k*z_step_um. wavelength_um: mean wavelength of the source. envelope_fwhm_um: the FWHM of the envelope along the scan axis. Give this or envelope_sigma_um, never both. It is half the source coherence length, because the double pass makes OPD = 2z; :func:csi_design returns both under separate names for exactly that reason. bias/amplitude: the intensity pedestal a and fringe amplitude b. reflectivity: per-pixel scale on the fringe amplitude (>= 0). It scales the envelope and therefore :func:csi_contrast_map, and — this is the honest part — it does not move the envelope peak, so it does not bias :func:csi_peak_position. A spatially varying reflectivity biases nothing either; what does bias the centroid is where the peak sits in the window, and that is documented on :func:csi_peak_position. noise: additive Gaussian sigma (0 = the exact model). seed: integer seed for that noise (no None).

Returns a 1-D float64 array of n_planes intensities.

Ground truth: with noise=0 and the surface centred in the scan, the "gaussian" estimator of :func:csi_peak_position returns surface_um to 1.43e-07 um over sub-step offsets, and to 2.9e-14 um when the envelope is given analytically instead of through the Hilbert transform (both pinned in the tests).

Raises ValueError: a non-real / non-finite / string / bool parameter, a non-positive z_step_um / wavelength_um / envelope width, a negative bias / amplitude / reflectivity / noise, n_planes outside [3, MAX_SCAN_POINTS], a z_step_um at or past the wavelength_um/4 Nyquist ceiling, and a surface_um outside the scan range (which is the case a real instrument reports as “no surface found”, not as a height).

詳しい使い方ガイド

coherence_scanning 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)

coherence_scanning — py -3.11 examples/coherence_scanning.py

型が繋がる次の op(`sweep` を入力に取れる)

csi_envelope · csi_peak_position · chromatic_confocal_height

同カテゴリ(`simulate`)

csi_stack_simulate · chromatic_confocal_simulate

Provenance: interferometry.py — INTERFEROMETRY 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)。

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