cavity op• Data kinds: none → pairs (an op determined by its arguments alone — it takes no image or data input)
• Call: import fullseye as fs; fs.ledger.pdh_error_signal(length_m: 'float' = 1.0, *, itm_transmittance: 'float' = 0.01, etm_transmittance: 'float' = 0.01, mod_freq_hz: 'float' = 20000000.0, mod_depth: 'float' = 1.08, power_w: 'float' = 1.0, span_linewidths: 'float' = 6.0, n_points: 'int' = 1201) -> 'np.ndarray' (to call the implementation directly, import cavityoptics; cavityoptics.pdh_error_signal(length_m: 'float' = 1.0, *, itm_transmittance: 'float' = 0.01, etm_transmittance: 'float' = 0.01, mod_freq_hz: 'float' = 20000000.0, mod_depth: 'float' = 1.08, power_w: 'float' = 1.0, span_linewidths: 'float' = 6.0, n_points: 'int' = 1201) -> 'np.ndarray'; from the registry, opsoptics.get("pdh_error_signal"))
Pound-Drever-Hall error signal ε(δ) as a function of the detuning δ [Hz] from resonance (pairs).
> The detailed description below is the original text — the summary and the headings are translated.
length_m : float
共振器長 L [m]。
itm_transmittance, etm_transmittance : float
鏡の強度透過率(損失なし)。
mod_freq_hz : float
位相変調周波数 Ω/2π [Hz]。線幅より十分大きいと傾きが Black の式 15 に乗る。
mod_depth : float
変調指数 β。搬送波 P_c = J₀(β)²P、側帯波 P_s = J₁(β)²P(β = 1.08 で P_c·P_s 最大)。
power_w : float
入射光量 P [W]。
span_linewidths : float
表示する離調の範囲(線幅の何倍まで、±)。
n_points : int
点数(奇数なら δ = 0 を含む)。
numpy.ndarray
(n_points, 2): 列 0 = 離調 δ [Hz]、列 1 = ε [W]
= 2√(P_c P_s)·Im[F(δ)F*(δ+Ω) − F*(δ)F(δ−Ω)]。
門(tests): 反対称 ε(−δ) = −ε(δ)(1e-12)、ε(0) = 0、対称共振器(T₁ = T₂)で Ω ≫ δν のとき共振近傍の傾き dε/dδ = −8√(P_c P_s)/δν(Black 2001 式 15)に 1 % 以内。側帯波が共振に乗る δ = ±Ω 付近の小さな山も含めて返す(表示範囲が届けば)。
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.
• 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.
• poc_gw_detector_pseudo_simulation — py -3.11 examples/poc_gw_detector_pseudo_simulation.py
pairs as input)mtf50 · energy_to_photons · spectral_product · spectral_integral · spectral_stats · kubelka_munk_reflectance · hyperspectral_capture · film_thickness_fft
cavity)fabry_perot_response · cavity_strain_transfer · michelson_dc_readout · quantum_noise_budget
*Provenance: cavityoptics.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.