PAVM
PAVM — Phantom Array Visibility Measure
Definition
PAVM is a perceptual metric for the phantom-array effect — the chain of bright dots that appears when a viewer moves their eyes across a high-frequency-modulated light source. It targets the band above ~2 kHz, beyond SVM. Discussed in CIE TR 249:2022 — but the standardized formula is incomplete.
Source overview
PAVM is intended to extend the SVM framework into the phantom-array regime, where eye saccades — rapid involuntary movements between fixation points — alias high-frequency light modulation onto the retina as discrete bright spots. CIE TR 249:2022 documents the phenomenon and proposes a measurement framework, but as of the report's publication the Minkowski exponent of the visibility-weighted aggregate is unspecified, and no complete normative formula exists. Implementations differ.
The underlying standard is paywalled or otherwise not directly reproducible here. The text above is a plain-language summary written by Slick Engineering — not a verbatim quote. Authoritative source linked below.
Technical detail
Practically, this means an app or hardware meter cannot ship a 'PAVM number' the way it can ship a PstLM or SVM number — the metric is still under standardization. FlickerSpec's design documents flag this explicitly and treat PAVM as a roadmap target subject to the standard finalizing.
Like SVM, PAVM cannot be computed from a 240 fps camera. It requires a high-rate photodiode (typically ≥ 200 kSPS for clean ≥ 5 kHz analysis per IES TM-39-25 §11.1).
Where it appears
- FlickerSpec Used here
Roadmap-after-SVM target. Requires both the photodiode attachment and the CIE TR 249 standardization to settle. Not yet shipping.
Related terms
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- PstLM
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- TLA
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