Theory 014/Optics & Photonics
Holograms Need Coherence Depth
The claim
Holographic image quality is set by coherence length relative to scene depth rather than by laser power, so a deep scene needs a longer coherence length.
01The mechanism
Interference requires path differences within coherence; beyond it, fringes wash out.
02Predictions
- P1Image quality should fall when depth exceeds coherence.
- P2Longer coherence should extend usable depth.
03Refutation
Quality independent of coherence at fixed depth would remove the constraint.