BLOG

What is Photometry

Horace He

Last Updated: December 26, 2023

What is Photometry

Photometry is the scientific discipline that focuses on the measurement and quantification of visible light as perceived by the human eye. It helps us understand and evaluate the performance and characteristics of lighting sources and systems.

Photometry measures and analyzes various photometric values, including luminous flux, luminous intensity, illuminance, and luminance. Luminous flux refers to the total amount of light emitted by a light source and is typically measured in lumens. Luminous intensity, on the other hand, quantifies the amount of light emitted in a specific direction and is measured in candelas.

Maybe You Are Interested In

  • Load Current: 10A Max
  • Auto/Sleep Mode
  • Time delay: 90s, 5min, 10min, 30min, 60min
  • Load Current: 10A Max
  • Auto/Sleep Mode
  • Time delay: 90s, 5min, 10min, 30min, 60min
  • Load Current: 10A Max
  • Auto/Sleep Mode
  • Time delay: 90s, 5min, 10min, 30min, 60min
  • Load Current: 10A Max
  • Auto/Sleep Mode
  • Time delay: 90s, 5min, 10min, 30min, 60min
  • Load Current: 10A Max
  • Auto/Sleep Mode
  • Time delay: 90s, 5min, 10min, 30min, 60min
  • Load Current: 10A Max
  • Auto/Sleep Mode
  • Time delay: 90s, 5min, 10min, 30min, 60min
  • Occupancy mode
  • 100V ~ 265V, 5A
  • Neutral Wire Required
  • 1600 sq ft
  • Voltage: DC 12v/24v
  • Mode: Auto/ON/OFF
  • Time Delay: 15s~900s
  • Dimming: 20%~100%
  • Occupancy, Vacancy, ON/OFF mode
  • 100~265V, 5A
  • Neutral Wire Required
  • Fits the UK Square backbox
  • Voltage: DC 12V
  • Length: 2.5M/6M
  • Color Temperature: Warm/Cold White
  • Voltage: DC 12V
  • Length: 2.5M/6M
  • Color Temperature: Warm/Cool White
  • Voltage: DC 12V
  • Length: 2.5M/6M
  • Color Temperature: Warm/Cool White
  • Voltage: DC 12V
  • Length: 2.5M/6M
  • Color Temperature: Warm/Cold White
rz036 occupancy sensor switch ceiling mounted
  • Occupancy mode
  • 12V ~ 24V, 5A
  • Neutral Wire Required
  • 1600 sq ft
  • Voltage: DC 12v/24v
  • Day/Night Mode
  • Time delay: 15min, 30min, 1h(default), 2h
  • Occupancy, Vacancy, ON/OFF mode
  • 100~265V 5A
  • Neutral Wire Required
  • Fits the US 1-Gang wall box
  • Occupancy, Vacancy, ON/OFF mode
  • 100~265V, 5A
  • Neutral Wire Required
  • Fits the US 1-Gang wall box
  • Occupancy, Vacancy, ON/OFF mode
  • 100~265V, 5A
  • Neutral Wire Required
  • Fits the European round backbox
rz021 us occupancy vacancy sensor switch front
  • Occupancy, Vacancy, ON/OFF mode
  • 100~265V, 5A
  • Requires Hot wire, Load wire
  • No Neutral/Ground Wire Required
  • Fits the US 1-Gang wall box
rz023 uk occupancy vacancy sensor switch front
  • Occupancy, Vacancy, ON/OFF mode
  • 100~265V, 5A
  • No Neutral/Ground Wire Required
  • Fits the UK square pattress box

Illuminance, measured in lux or foot-candles, is a metric in photometry that indicates the amount of light falling on a surface. It provides insights into the density of the luminous flux on that surface. Luminance, measured in candelas per square meter or foot-lamberts, represents the brightness of a surface as perceived by an observer.

Looking For Motion-Activated Energy-Saving Solutions?

Contact us for complete PIR motion sensors, motion-activated energy-saving products, motion sensor switches, and Occupancy/Vacancy commercial solutions.

To obtain accurate photometric data, specialized devices are used. The integrating sphere is commonly employed to measure the electrical features and chromatic properties of a light source, such as the luminous flux. It provides comprehensive information about the total light output of a source. Another essential device is the goniophotometer, which measures the spatial and angular distribution of light. It helps determine how the light is distributed in different directions and angles.

Leave a Comment

en_USEnglish