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Focused Ion Beam SEM (FIB-SEM) — serial sectioning 3D imaging L1-093

Electron MicroscopyIon-mill serial sectioning + SEMδ=5 · challengingL_DAG = 4📋 Stub — not mineable
📋

Unclaimed Principle — open for contribution

This Principle is declared in the catalog but has no reference solver, no pinned dataset, and is not registered on-chain. There is no reward pool. Submitting a cert against this Principle today will record the cert for reproducibility but pay zero PWM.

To claim it as a Bounty #7 contribution: open a PR adding (1) a reference solver, (2) ≥1 dataset pinned to IPFS, (3) updates to the L3 manifest with dataset CIDs. After verifier-agent triple-review, the founders' 3-of-5 multisig signs PWMRegistry.register() and the Principle becomes mineable.

Forward model E

Focused Ion Beam SEM (FIB-SEM) — serial sectioning 3D imaging: fib milling sem produces the measurement through a 5-node primitive DAG L.ion_milling -> L.excitation.electron_beam -> S.scan.raster -> S.scan.axial -> int.temporal, with axial/z-step integration and photon-shot-noise-limited (Poisson counting). Recovery is posed as a linear inverse problem that inverts the forward operator to estimate the scene-side 3D intensity. Difficulty tier delta=5 with effective condition number kappa_eff~15; calibration-level mismatch (milling_step_variance, curtain_artifact, charging) sets the accuracy floor at the Omega boundary. See the forward_model field for the closed-form imaging equation.

L-DAG

L.ion_milling -> L.excitation.electron_beam -> S.scan.raster -> S.scan.axial -> int.temporal
L.ion_millingL.excitation.electron_beamS.scan.rasterS.scan.axialint.temporal

Well-posedness W

Existence:
true
Uniqueness:
true
Stability:
conditional
κ:
300

Existence of the recovered 3D intensity is guaranteed within the declared Omega bounds. Uniqueness holds on the measurement-supported subspace; out-of-support modes are controlled by the declared priors. Stability is moderately conditioned (kappa_eff ~= 15); milling_step_variance dominates the stability cliff; curtain_artifact and the remaining mismatch parameters contribute higher-order bias terms. Photon-shot-noise-limited (poisson counting) sets the irreducible data-fidelity floor, while mild Tikhonov or analytic inversion is sufficient at the nominal Omega point.

Solvability C

Solver class:
linear-operator + analytic regularisation [BM3D-FIBSEM] | linear-operator + deep neural prior [DeepCurtain-Remove, 3D-UNet-FIBSEM]
Convergence rate q:
2
Complexity:
O(H * W * Z * log(...)) per iteration; learned variants: O(H W Z * F_theta_cost) per forward pass

Specs (0)

No L2 specs registered yet for this principle.