plenoptic op• 数据种类:lightfield × table → table
• 调用: import fullseye as fs; fs.ledger.plenoptic_refocus_depth(lf, system, slope)(要直接调用实现,import plenoptic; plenoptic.plenoptic_refocus_depth(lf, system, slope);从台账取用则 opsoptics.get("plenoptic_refocus_depth"))
• GPU:无(仅 CPU 参考实现)
将光场重聚焦斜率转换为以米为单位的物距。
> 以下的详细说明为原文 —— 摘要与标题已翻译。
*slope* is in the unit of lightfield.lf_refocus and lightfield.lf_depth_from_focus on a field from plenoptic_decode: decoded spatial samples (lenslets) of parallax per view step. Zero slope is the main-lens conjugate of the MLA plane and maps to the configured object distance.
Paraxial model of the unfocused (1.0) camera, in the geometry plenoptic_capture traces. plenoptic_decode samples U views across one lenslet pitch, so one view step moves the exit-pupil coordinate by dX = (pitch/U) * xp_radius / (microimage_diameter/2). A point imaged delta behind the MLA plane, with the exit pupil D in front of it, shifts on the MLA by dX * delta/(D+delta) per view, hence slope = (dX/pitch) * delta/(D+delta); Newton's equation of the paraxial main lens turns the image position into the object distance.
Before 2026-11-04 the image shift was slope * angular_step * pitch with angular_step = pixel_pitch/mla_to_sensor -- a factor 1/angular_step**2 (~3000x for the PoC camera) too small, so every measured slope mapped back to the focus distance. The relation is now gated against rays traced forward through the prescription (tests/test_plenoptic.py): rel. error below 1e-6 for an ideal lens and 2e-4 for the PoC's three-element lens.
Sign: follows plenoptic_capture's non-inverting pixel-to-pupil map, which is the opposite of a physical lenslet; negate real-sensor slopes.
Limits: it is paraxial. Spherical aberration of a real aperture moves the best-focus slope of the full pupil away from the paraxial one -- for the PoC lens at F/3.7 the decoded 1.0 m plane sits at slope -0.029, not 0 (measured in examples/poc_plenoptic_camera.py). depth_resolution_m is half the depth span of a slope change of +-1/(U-1): one decoded sample of parallax across the full angular baseline.
Raises ValueError: *lf* not (V,U,H,W), V != U (one slope cannot describe two different per-view pupil steps), fewer than two views, a focused (2.0) system (its MLA is not at the main-lens image plane, so slope means something else), a non-finite slope, or a slope whose image point lies at or beyond the exit pupil (slope*pitch/dX >= 1).
optics 的每个算子都先校验输入再计算(不让任何东西无声通过):
• 单位写进参数名 —— _mm / _um / _deg / _mrad。把 mm 和 µm 弄混不会崩溃,而是给出「看着合理却是错的答案」,所以用命名来防。这里绝不从数值大小去猜单位。
• 字符串一律 ValueError —— float('50') 会成功,于是未解析的配置值会被当成长度混进来(实测:thin_lens('50', '200') 曾返回看着合理的 66.667 mm)。bool 也按 True == 1 的隐式提升拒绝。
• complex / masked array 一律 ValueError(仅接受实数槽位;拒绝无声丢弃虚部或剥掉掩码)。所有输入中的 NaN/Inf 一律 ValueError。但已声明的缺测除外:bottle_fit_from_pattern 的 u_map 以 NaN 接收未能测得的像素(∞ 仍被拒绝)。
• 逐项点名拒绝除零及其近亲:焦距 0、曲率半径 0、折射率 <= 0、全不透明光阑(全为 0,归一化变成 0/0)、总和 <= 0 的 PSF、S0 = 0 的 Stokes 矢量、物体位于前焦点(像在无穷远)。
• 只有两个算子会返回非有限值,而且都写进了契约:depth_of_field 在超焦距以外返回 far_mm = inf(这正是超焦距的定义),gaussian_beam 在束腰处返回 wavefront_radius_mm = inf(平面波前的曲率半径)。两者都同时返回一个有限的搭档(far_is_infinite / curvature_per_mm)。除此之外的无声 NaN/Inf 都在内部检出并 ValueError ——「float64 溢出了」和「答案是无穷大」是两种不同的主张,不能拿后者的脸去交付前者。但已声明的缺测除外:bottle_background_map 对光线不可用的像素(全反射等)在 u_mm 中返回 NaN,并同时返回 valid 掩码和数量。
• 尺寸上限:生成网格受 optics.MAX_GRID(4096)限制,传入的场/PSF/光阑受 optics.MAX_FIELD_ELEMENTS(2^24),ABCD 元件序列受 optics.MAX_SYSTEM_ELEMENTS(1024),Zernike 受 MAX_ZERNIKE_TERMS(512)/ MAX_ZERNIKE_ORDER(40)/ MAX_ZERNIKE_BASIS(2^25)。以 fail-closed 堵住「小参数引发巨大内部分配」的路径(实测:n_max=40 × 4096² 需要 108 GB)。
• 物理上不可能的状态同样拒绝:偏振度 > 1 的 Stokes 矢量、负透过率、负强度、n-|m| 为奇数等非法 Zernike 指标。
• 示例数据目录(下载 URL / 许可证) —— 2-D 用 skimage.data(BSD/公有领域)加合成图,3-D 给出真实数据源(Stanford/PDS 等)的下载 URL。
• 算子来历与参考文献 —— 该算子族所依据的研究/方法出处。
• 算法的正典(作者、年份)与用途见上面的族使用指南。
• poc_plenoptic_camera — py -3.11 examples/poc_plenoptic_camera.py
table 作为输入)abcd_matrix · wavefront_stats · sfr_from_edge · paraxial_trace · seidel_coefficients · spot_stats · tolerance_analysis · wavefront_from_opd
plenoptic)mla_surface · plenoptic_system · plenoptic_capture · plenoptic_mla_calibrate · plenoptic_decode
*Provenance: plenoptic.py — OPTICS 算子登记表。本条目由 tools/opdocs.py md 自动生成(请勿手工编辑)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.