# 📐 L2 Spec — Near-Field Scanning Optical Microscopy (NSOM/SNOM) Mismatch-Only Spec
**ID:** `L2-164-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-164`](/artifact/l1/L1-164)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.55 · **Delta tier:** 5
> **⛓ On-chain block:** 41554246
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| H | px | 64 |
| W | px | 64 |
| Snr db | dB | 0.0 – 40.0 |
| Pixel nm | nm | 1 – 100 |
| Aperture nm | nm | 10 – 500 |
| Peak photons | photons | 10 – 10000 |
| Optical coupling | — | 0.3 – 1.0 |
| Vibrational noise | — | 0.0 – 0.3 |
| Tip sample distance | — | 1 – 50 |
| Aperture contamination | — | 0.0 – 0.5 |
## 2. Tolerance (ε)
**Type:** `fn`
```
14.0 + 2.0 * log10(peak_photons / 10) + 5.0 * optical_coupling - 8.0 * aperture_contamination - 0.1 * tip_sample_distance
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.55 |
| Delta tier | 5 |
## 4. Fingerprint
`ed1b2d7c3dbd4c091e9b121f7ab37062cadfabd3487318273f3f919225358db5`
## 5. On-chain Registration
- **Chain hash:** `0x9ee57d7c6a48348b54b0b2d48c505c71947322c778f7384daa4ca7da7215a7c0`
- **Chain tx hash:** `0x39ab4dab1493eb0c6f2c8715100a24a4563f3b1c5e05f73a399da4f8e87573a5`
- **Chain block:** `41554246`
---
## File Mapping
This bundle consists of: `L2-164-001.md`, `L2-164-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-164-001.md` | Source of truth — edit this | Human or LLM |
| `L2-164-001.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 `L2-164-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._