# ⚛  L1 Principle — Light Sheet Fluorescence Microscopy (LSFM / SPIM)

**ID:** `L1-006` · **Status:** ⊙ Testnet (genesis catalog)

> **🌐 Domain:** Microscopy — *Selective plane illumination 3D imaging*
> **🎯 Problem class:** linear inverse · **🧮 Solution space:** 3D intensity
> **📡 Carrier:** photon · **🌫 Noise:** poisson gaussian
> **⚖ Difficulty (δ):** 3 · **⛓ Block:** 41554154

---

## 🧠 1. Introduction

**Light Sheet Fluorescence Microscopy (LSFM / SPIM)** is a **linear inverse problem** whose unknown lives in **3D intensity** space, within the **Selective plane illumination 3D imaging** sub-domain of **Microscopy**.

Measurements consist of photons collected by an optical detector via a **light sheet illumination** sensing mechanism.

The forward operator applies, in order: L · illumination · sheet operator; K · psf · detection operator; S · scan · axial operator; detector accumulates flux over the exposure window.

Observations are corrupted by Poisson shot noise plus Gaussian read-out noise. 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 ~= 10); sheet_thickness_nm dominates the stability cliff; sheet_tilt and the remaining mismatch parameters contribute higher-order bias terms. Poisson signal noise + gaussian read noise sets the irreducible data-fidelity floor, while mild Tikhonov or analytic inversion is sufficient at the nominal Omega point.

## ⚙ 2. Forward Model

Physical chain: **x** → L · illumination · sheet → K · psf · detection → S · scan · axial → Temporal integration → **y** (detector).

```
y = ∫_t dt `S.scan.axial` `K.psf.detection` `L.illumination.sheet` x + n,    Poisson + 𝒩(0, σ²)
```

**Measurement DAG:**

| Primitive | What it does |
|---|---|
| `L.illumination.sheet` | L · illumination · sheet operator |
| `K.psf.detection` | K · psf · detection operator |
| `S.scan.axial` | S · scan · axial operator |
| `int.temporal` | Detector accumulates flux over the exposure window |

## 🔬 3. Physics Fingerprint

| Property | Value |
|---|---|
| Domain | Microscopy |
| Sub domain | Selective plane illumination 3D imaging |
| Carrier | photon |
| Problem class | linear_inverse |
| Solution space | 3D_intensity |
| Noise model | poisson_gaussian |
| Integration axis | axial |
| Difficulty delta | 3 |
| L dag | 3.2 |

## 📡 4. Measurement Model

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 ~= 10); sheet_thickness_nm dominates the stability cliff; sheet_tilt and the remaining mismatch parameters contribute higher-order bias terms. Poisson signal noise + gaussian read noise sets the irreducible data-fidelity floor, while mild Tikhonov or analytic inversion is sufficient at the nominal Omega point.

| Metric | Value |
|---|---|
| Metric | PSNR_dB |
| Secondary | SSIM |

## 📏 5. Operating Range (Ω)

**Center problem class:** `lsfm` · **Forward operator:** `lsfm_forward`

**Center point:**

| Parameter | Unit | Value |
|---|---|---|
| H | px | 2048 |
| W | px | 2048 |
| Z | — | 200 |
| Na det | — | 1 |
| Sheet nm | nm | 2000 |
| Z step nm | nm | 500 |
| Sheet tilt | — | 0 |
| Peak photons | photons | 500 |
| Sample induced aberration | — | 0 |

**Allowed bounds:**

| Parameter | Unit | Range |
|---|---|---|
| H | px | 512 – 4096 |
| W | px | 512 – 4096 |
| Z | — | 32 – 1024 |
| Na det | — | 0.8 – 1.2 |
| Sheet nm | nm | 500 – 5000 |
| Z step nm | nm | 200 – 2000 |
| Sheet tilt | — | 0.0 – 0.05 |
| Peak photons | photons | 50 – 5000 |
| Sample induced aberration | — | 0.0 – 0.3 |

## 🎯 6. Tolerance (ε)

**Center tolerance:** 29.0

| Metric | Range |
|---|---|
| Psnr db | 12.0 – 42.0 |

## ⚖ 7. Hardness Function

Hardness scales as **`epsilon_fn`** on **PSNR_dB**, with κ = `200` and δ = `3`.

## 💾 8. Reference Dataset

- **primary** · weight 1.0 · IPFS _(not pinned yet)_

## 9. On-chain Registration

- **Chain hash:** `0x4552e070d72334485b84438a43401a9f2900af150b67411a605d469039af1ed8`
- **Chain tx hash:** `0xf9bccafe6d9127f4a84d783a9d930d7f838b507744c534769e550555ddd1ef65`
- **Chain block:** `41554154`

---

## File Mapping

This bundle consists of: `L1-006.md`, `L1-006.json`.

| File | Role | How to regenerate |
|------|------|-------------------|
| `L1-006.md` | Source of truth — edit this | Human or LLM |
| `L1-006.json` | Structured metadata for the registry | LLM regenerates from the sections above |

**Prompt for your LLM after editing this Markdown:**

> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.

_This Markdown was auto-synthesized from the catalog row for `L1-006`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._