lens_scene — OPTICS lensrender 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.lens_scene(objects=None, lights=None, sources=None, background=0.0, ambient=None, shadows=True) -> 'dict' (to call the implementation directly, import lensrender; lensrender.lens_scene(objects=None, lights=None, sources=None, background=0.0, ambient=None, shadows=True) -> 'dict'; from the registry, opsoptics.get("lens_scene"))

• GPU: none (CPU reference implementation only)

Usage

Build and validate a simple 3-D scene for render_scene_through_lens -> dict (the scene table).

*objects* is a list of dicts. {"type": "plane", "z_mm": -1000, "size_mm": (w, h), "albedo": ...} is a plane facing the lens (point_mm and normal / up tilt it; with size_mm it is the rectangle around the point, without it it is infinite) whose albedo may be a texture (H, W) or (H, W, 3) mapped onto the rectangle with bilinear sampling (row 0 at the top, up is the picture's up). {"type": "sphere", "center_mm": (x, y, z), "radius_mm": r} and {"type": "mesh", "vertices_mm": (V, 3), "faces": (F, 3)} (Moller-Trumbore, flat shading) take the same material keys:

albedo (a number, an (R, G, B) triple at the effective wavelengths 0.61 / 0.54 / 0.465 um, or {"nm", "value"}), specular (the weight ks of a normalised Blinn-Phong lobe, whose albedo is about ks), shininess and emission (spectral radiance of a self-luminous surface, W m^-2 sr^-1 nm^-1). *lights*: {"type": "directional", "to_light": (x, y, z), "irradiance_W_m2_nm": E} (E at normal incidence) or {"type": "point", "position_mm": ..., "intensity_W_sr_nm": I}; shadow rays are traced when *shadows* is true. *ambient* is a spectral irradiance (default 0, or 0.05 in the demo scene) that lights every surface without shadows; *background* is the spectral radiance a ray that hits nothing sees. *sources* are bright points seen by the camera, {"position_mm": (x, y, z), "intensity_W_sr_nm": I}: they are splatted by forward ray tracing (point sources cannot be found by random rays from the sensor), do not occlude and cast no shadows. With nothing given the table is a demo: a 2 mm checkerboard plane, a glossy sphere, one directional light and a little ambient light. Unknown keys, a degenerate triangle, a negative albedo or a tabulated spectrum outside its range are refused.

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)

• plenoptic_capture_pipeline — py -3.11 examples/plenoptic_capture_pipeline.py

• poc_photograph_through_prescription — py -3.11 examples/poc_photograph_through_prescription.py

• poc_plenoptic_camera — py -3.11 examples/poc_plenoptic_camera.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)

exit_pupil_samples · trace_sensor_rays · 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.