trace_sensor_rays — OPTICS lensrender op

• Data kinds: table → table

• Call: import fullseye as fs; fs.ledger.trace_sensor_rays(system, pixel_xy_mm=None, pupil_xy_mm=None, wavelength_um=None, defocus_mm=0.0, fresnel=False, focus_mm=None) -> 'dict' (to call the implementation directly, import lensrender; lensrender.trace_sensor_rays(system, pixel_xy_mm=None, pupil_xy_mm=None, wavelength_um=None, defocus_mm=0.0, fresnel=False, focus_mm=None) -> 'dict'; from the registry, opsoptics.get("trace_sensor_rays"))

Usage

Trace rays from sensor points through exit-pupil points backwards to object space -> dict.

*pixel_xy_mm* (M, 2) are points (x, y) in the image plane (lens-frame axes, the image is inverted); *pupil_xy_mm* (K, 2) are points in the exit-pupil plane (default: 16 hexapolar samples of exit_pupil_samples). All M x K pairs are traced through every surface from the last to the first (Snell's law at *wavelength_um* with the dispersion of each medium, conics and aspheres, mirrors, the semi-diameters as apertures, total internal reflection); the sensor plane is the system's image plane (or the paraxial image of an object at *focus_mm*) moved by *defocus_mm* along the light. The table has origin / direction (M, K, 3): where the ray leaves the first surface and its unit direction into the scene (NaN where lost), transmission (M, K) - 1 for a ray that gets out, or with fresnel=True the product of the unpolarised Fresnel transmittances of the refracting surfaces (no coating, no absorption), 0 for a lost ray - vignetted (M, K) (any loss: a semi-diameter, a miss, TIR), tir, geometry_mm2 (cos^2(theta) / d^2 of the pupil sample seen from the sensor point, the weight of the irradiance integral), z_sensor_mm, z_pupil_mm and wavelength_um. Reversibility is exact: a forward ray from raytrace.ray_bundle traced back from its image point through its exit-pupil point returns to its entrance point (tested to 1e-9 mm and 1e-12 in direction).

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_photograph_through_prescription — py -3.11 examples/poc_photograph_through_prescription.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 (lensrender)

lens_scene · exit_pupil_samples · scene_radiance · render_scene_through_lens · bokeh_shape · render_ghost_overlay · render_compare_prescriptions


*Provenance: lensrender.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.