Diffraction Limit / Optimal Aperture Calculator

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Audio, Music, Photography & Color

Tranche

tranche-5

Evidence ID

t5-077

Ledger rows

1

No ledger note is attached.

Review findings

The honest-label warning about physical-optics approximation and lens quality is appropriate but incomplete. The product must disclose the explicit diffraction criterion and resolve the contradiction between N=pixelPitch/(1.22λ) and Airy diameter=2.44λN before claiming a standard diffraction-limit calculation.

Formula and scope findings

• The stated formula N≈pixelPitch/(1.22*λ) is not consistent with the stated Airy-disk diameter formula when the criterion is that the Airy disk diameter equals one pixel. Substitution gives Airy diameter=2.44*λ*(pixelPitch/(1.22*λ))=2*pixelPitch. Under the one-pixel Airy-diameter criterion, the corresponding formula is N≈pixelPitch/(2.44*λ).
• The phrase "begins to visibly limit resolution" does not define a unique optical criterion. Depending on the chosen criterion, the relevant comparison may involve Airy-disk diameter, Airy radius, pixel pitch, or sensor Nyquist frequency; the criterion must be stated explicitly.
• The sensor megapixels-and-size input path does not specify whether size means active width and height, diagonal, or nominal format size, nor does it specify the aspect ratio and active-area assumptions needed to derive pixel pitch.

Unit assumptions

• Pixel pitch and wavelength must use the same length unit; with λ=0.00055 mm, pixel pitch must be supplied in millimetres or converted to millimetres.
• The default λ≈0.00055 mm means 550 nm monochromatic green light; real scenes and sensors respond over a wavelength band.
• For megapixel-plus-size calculations, the sensor dimensions are assumed to be active imaging width and height in millimetres, pixels are square, and the stated megapixel count is the active pixel count.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

The specification does not state validation behavior for zero megapixels, zero or negative pixel pitch, or other nonphysical inputs. Zero megapixels creates a division-by-zero during derived pixel-pitch calculation, while negative pixel pitch produces sign-dependent and physically invalid outputs unless explicitly rejected or converted to an absolute magnitude.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "manual_pixel_pitch_mm": 0.004,
    "wavelength_mm": 0.00055
  },
  "expected_outputs": {
    "diffraction_limited_f_number": 5.961252,
    "airy_disk_diameter_mm": 0.008
  },
  "working": "1.22*λ = 1.22*0.00055 = 0.000671 mm. N = 0.004/0.000671 = 5.961252. Airy diameter = 2.44*0.00055*5.961252 = 0.008000 mm, equivalently 2*0.004 = 0.008000 mm."
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche5/tranche5-results.json
• BOUNDARY_HAZARD_CATALOG.json