coherent op• Data kinds: none → image2d (an op determined by its arguments alone — it takes no image or data input)
• Call: import fullseye as fs; fs.ledger.laser_line_coherent(shape=(96, 512), wavelength_um=0.65, sin_u_obs=0.05, pixel_um=2.0, line_width_um=20.0, height_um=20.0, sin_theta=0.5, row0=None, polarizations=1, n_patterns=1, pixel_oversample=2, roughness_rad=None, noise=0.0, seed=0, noise_seed=None) (to call the implementation directly, import coherent; coherent.laser_line_coherent(shape=(96, 512), wavelength_um=0.65, sin_u_obs=0.05, pixel_um=2.0, line_width_um=20.0, height_um=20.0, sin_theta=0.5, row0=None, polarizations=1, n_patterns=1, pixel_oversample=2, roughness_rad=None, noise=0.0, seed=0, noise_seed=None); from the registry, opsoptics.get("laser_line_coherent"))
A sheet-of-light laser line on a rough surface, imaged with its speckle (image2d).
Object-side coordinates, magnification 1: one output pixel covers pixel_um on the part. The line is a Gaussian band along the columns, intensity 1/e² half-width line_width_um (as seen by the camera), centred on the row row0 + height_um · sin_theta / pixel_um (height_um a number or one value per column, default 20 µm so that sin_theta acts on the default call; row0 defaults to the middle row) — the triangulation shift. Its amplitude multiplies a random phase screen fixed to the part (seed), the field passes the observation pupil sin_u_obs (cut-off sin_u/λ), and the intensity is integrated over each pixel (pixel_oversample). polarizations × n_patterns independent patterns are averaged (a moving diffuser / several wavelengths). noise adds Gaussian read noise of that standard deviation relative to the line's peak mean intensity (seeded by noise_seed, so a static part with several noisy frames is same seed, different noise_seed). The mean peak intensity is 1.
The true centre row is returned implicitly by the formula above; see triangulation_speckle_limit for the floor this sets. Limits: scalar, paraxial, in focus, no foreshortening of the line width with θ, no Scheimpflug, phase screen uncorrelated between fine samples.
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_laser_line_speckle_floor — py -3.11 examples/poc_laser_line_speckle_floor.py
image2d as input)fraunhofer_pattern · pupil_psf · pupil_blur · psf_to_mtf · edge_spread · veiling_glare_index · emva_pair_statistics · emva_defect_pixels
coherent)coherent_image · speckle_field · speckle_statistics · triangulation_speckle_limit · speckle_reduction
*Provenance: coherent.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.