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 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) (または 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)。*

csi_signal_simulate — INTERFEROMETRY simulate op

使い方