tdi_sync_mtf — OPTICS linescan op

• Data kinds: none → table (an op determined by its arguments alone — it takes no image or data input)

• Call: import fullseye as fs; fs.ledger.tdi_sync_mtf(frequency_cyc_px=None, stages=64, sync_error=0.0, yaw_deg=0.0) (to call the implementation directly, import linescan; linescan.tdi_sync_mtf(frequency_cyc_px=None, stages=64, sync_error=0.0, yaw_deg=0.0); from the registry, opsoptics.get("tdi_sync_mtf"))

Usage

MTF of the blur caused by a TDI synchronisation error and by yaw (a skewed web) (closed form, table).

> The detailed description below is the original text — the summary and the headings are translated.

TDI は電荷を 1 ライン周期に 1 行ずつ送り、被写体も同じだけ進めば N 段が同じ物点を足す。速度(またはラインレート)の相対誤差 ε があると 1 段ごとに像が ε 画素ずつ滑り、N 段で L = N·|ε| 画素の一様な掃引になる。一様な掃引の MTF は |sinc(f L)|(np.sinc = sin(πx)/(πx))—— 最初の零は f = 1/L。

ヨー角 θ(web の流れがセンサの走査軸から θ 傾く)では、web の軸で測った 1 段あたりの滑りが流れ方向 (1 + ε) − cos θ、幅方向 sin θ になる(電荷は走査軸に沿って動くので)。幅方向のぼけ N·|sin θ| 画素は同期を完全にしても残る —— エンコーダ同期では直らない。

*frequency_cyc_px*: 周波数 [cycles/画素] (既定 0〜0.5 を 51 点)。返り値 dict: frequency / mtf_scan(流れ方向)/ mtf_cross(幅方向)/ slip_scan / slip_cross(1 段あたり [画素])/ smear_scan_px / smear_cross_px(N 段ぶん)/ first_zero_scan(1/L、ぼけが無ければ None)。

★入れていないもの: 同期が完全でも電荷の送りが離散なので 1 画素ぶんの掃引(sinc(f))が残るが、これは全条件に共通で、多相クロックでは減る。比べたい差は同期の側なので掛けていない。

Raises ValueError: 周波数が負・非有限・1-D でない / 段数が範囲外 / |ε| > 0.5 / |θ| > 30°。

Family-wide input contract (fail-closed)

Every optics op validates its input before computing (nothing slips through silently):

• Units are baked into the argument name — _mm / _um / _deg / _mrad. Confusing mm with µm does not crash; it yields a plausible-looking wrong answer, so the name prevents it. Nothing here guesses the unit from the magnitude.

• Strings raise ValueError — float('50') succeeds, so an unparsed configuration value would slip through as a length (measured: thin_lens('50', '200') returned a plausible 66.667 mm). bool is refused too, as the implicit promotion True == 1.

• complex / masked arrays raise ValueError (real-valued slots only; silently dropping the imaginary part or peeling off the mask is refused). NaN/Inf raises ValueError on every input.

• Division by zero and its relatives are refused by name: focal length 0, radius of curvature 0, refractive index <= 0, a fully opaque aperture (all zeros, so the normalisation is 0/0), a PSF whose sum is <= 0, a Stokes vector with S0 = 0, and an object sitting at the front focal point (the image is at infinity).

• Only two ops return a non-finite value, and both state it as a contract: depth_of_field returns far_mm = inf beyond the hyperfocal distance (that is what the hyperfocal distance means), and gaussian_beam returns wavefront_radius_mm = inf at the waist (the radius of curvature of a plane wavefront). Both also return a finite companion (far_is_infinite / curvature_per_mm). Any other silent NaN/Inf is detected internally and raises ValueError — "float64 overflowed" and "the answer is infinite" are different claims, so the first is never returned wearing the face of the second.

• Size caps: generated grids are capped by optics.MAX_GRID (4096); supplied fields/PSFs/apertures by optics.MAX_FIELD_ELEMENTS (2^24); ABCD element chains by optics.MAX_SYSTEM_ELEMENTS (1024); Zernike by MAX_ZERNIKE_TERMS (512) / MAX_ZERNIKE_ORDER (40) / MAX_ZERNIKE_BASIS (2^25). This closes, fail-closed, the paths where a small argument triggers a huge internal allocation (measured: n_max=40 × 4096² needs 108 GB).

• Physically impossible states are refused too: a Stokes vector with degree of polarisation > 1, negative transmittance, negative intensity, and invalid Zernike indices such as n-|m| odd.

Detailed usage guide

• optics_imaging family guide

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• poc_tdi_linescan — py -3.11 examples/poc_tdi_linescan.py

Ops the type connects to (they accept table as input)

abcd_matrix · wavefront_stats · sfr_from_edge · paraxial_trace · seidel_coefficients · spot_stats · tolerance_analysis · wavefront_from_opd

Same category (linescan)

tdi_snr · linescan_acquire · lens_field_profile · linescan_lens_columns · linescan_lens_example


*Provenance: linescan.py — OPTICS operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

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