light_transport op• Data kinds: images → table
• Call: import fullseye as fs; fs.ledger.micro_phase_decode(images, periods=(14.0, 15.0, 16.0), n_shifts=4) (to call the implementation directly, import lighttransport; lighttransport.micro_phase_decode(images, periods=(14.0, 15.0, 16.0), n_shifts=4); from the registry, opsoptics.get("micro_phase_decode"))
Decode a narrow-band high-frequency fringe set (micro phase shifting, Gupta & Nayar 2012) into an absolute projector coordinate, ordering the fringes by the beat of the first two periods.
*images* is the concatenation of n_shifts phase-shifted sinusoids per period (as high_frequency_patterns with kind="sinusoid" and a sequence of periods returns them). Each period is decoded with fringe.wrapped_phase; the beat φ1 − φ2 of the first two periods is a synthetic fringe of period p1 p2 / |p1 − p2|, which fixes the fringe order of every period; the coordinate is the mean over periods. Because every period is short, the global light seen by a pixel is nearly the same in all frames and barely moves the phase. (Gupta & Nayar solve F + 2 images jointly and order with Gushov–Solodkin; neither is implemented here.)
Returns a dict (a table): coordinate (H, W) in projector pixels, unambiguous over [0, synthetic_period); wrapped_phase (F, H, W); coarse (the beat estimate); synthetic_period.
Raises ValueError: images not len(periods) * n_shifts finite 2-D frames of one shape; fewer than 2 periods, a period <= 2, or the first two equal; *n_shifts* not an integer in [3, 64].
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_interreflection_fringe_error — py -3.11 examples/poc_interreflection_fringe_error.py
table as input)abcd_matrix · wavefront_stats · sfr_from_edge · paraxial_trace · seidel_coefficients · spot_stats · tolerance_analysis · wavefront_from_opd
light_transport)groove_profile · form_factors_2d · transport_matrix_radiosity · high_frequency_patterns · render_transport · separate_direct_global · fringe_multipath_phase_error · predict_fringe_phase_error
*Provenance: lighttransport.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.