cavity 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.fabry_perot_response(length_m: 'float' = 3994.5, wavelength_nm: 'float' = 1064.0, *, itm_transmittance: 'float' = 0.014, etm_transmittance: 'float' = 5e-06, itm_loss: 'float' = 0.0, etm_loss: 'float' = 0.0) -> 'dict' (to call the implementation directly, import cavityoptics; cavityoptics.fabry_perot_response(length_m: 'float' = 3994.5, wavelength_nm: 'float' = 1064.0, *, itm_transmittance: 'float' = 0.014, etm_transmittance: 'float' = 5e-06, itm_loss: 'float' = 0.0, etm_loss: 'float' = 0.0) -> 'dict'; from the registry, opsoptics.get("fabry_perot_response"))
Design quantities of a Fabry-Perot cavity (FSR, finesse, linewidth, pole, power gain, storage time) in closed form.
> The detailed description below is the original text — the summary and the headings are translated.
length_m : float
共振器長 L [m]。既定は aLIGO の腕(3994.5 m)。
wavelength_nm : float
レーザー波長 [nm]。既定 1064 nm(Nd:YAG)。
itm_transmittance, etm_transmittance : float
入力鏡・終端鏡の強度透過率(0 ≤ T < 1)。既定は aLIGO(1.4 % / 5 ppm)。
itm_loss, etm_loss : float
各鏡の強度損失(吸収 + 散乱)。T + ℓ < 1。
dict
fsr_hz = c/2L、finesse = π√(r₁r₂)/(1 − r₁r₂)、
linewidth_hz(半値全幅、厳密に FSR·(2/π)·asin(π/2F))、
linewidth_approx_hz = FSR/F、pole_hz = 線幅の半分(共振器の極)、
storage_time_s = 1/(2π·pole)、power_gain = 共振での循環光量/入射光量
= T₁/(1 − r₁r₂)²、transmission_max = T₁T₂/(1 − r₁r₂)²、
reflection_min = 共振での反射率 ((r₁ − r₂(1−ℓ₁... ))/(1 − r₁r₂))² の
損失なし形 ((r₁ − r₂)/(1 − r₁r₂))²、r1 / r2、round_trip_phase_per_hz
= 4πL/c、free_spectral_range_mode_number = 2L/λ(共振の次数、参考値)。
aLIGO の既定値で F ≈ 445、FSR 37.5 kHz、線幅 84 Hz、極 42 Hz、循環光量 ≈ 280 倍(入力鏡の透過 1.4 % に対して)。linewidth_hz と pole_hz は Airy 関数の半値を 厳密に与える(asin 形)ので、tests では透過曲線を細かく標本化して半値の交点を独立に探し、この値と突き合わせる。
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
table as input)abcd_matrix · wavefront_stats · sfr_from_edge · paraxial_trace · seidel_coefficients · spot_stats · tolerance_analysis · wavefront_from_opd
cavity)cavity_strain_transfer · michelson_dc_readout · pdh_error_signal · 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.