Threshold illuminance

{
  "id": "MLC-T-MET-009638",
  "term": "Threshold illuminance",
  "field": "Meteorology and atmospheric science",
  "definition": "The minimum level of light intensity required for the human eye to perceive an object or for a light-sensitive instrument to detect a signal. In meteorology, it relates to visibility and the detection of faint light sources, such as distant stars or navigation lights. The threshold illuminance for scotopic (night) vision is significantly lower than for photopic (day) vision.",
  "see_also": [
    "Allard's law",
    "night visual range"
  ],
  "url": "https://mlchart.com/terminology/meteorology/threshold-illuminance/"
}