ANSI/IES LS-1-22, Lighting Science: Nomenclature and Definitions for Illuminating Engineering
The IES defines illumination engineering terms in ANSI/IES LS-1-22, is available here online. You can search terms by their first letter using the categories listed in the Categories window, by the first letter of the term in the alphabetical list below, or by typing the term in the search window. You can find the Introduction material for LS-1-22 on these pages:
- Copyright, Disclaimer, and American National Standards Statement
- Foreword, Nomenclature Committee members, Introduction, and Scope
- Spectral Parameters Used in Illumination Engineering
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- Obie light
- object color
- obstruction beacon
- obstruction lights (aeronautical lighting)
- obtrusive light
- occulting light
- occupancy sensor
- olivette
- on-off ratio (or mark-space ratio) for a repeated single flash
- one-K
- opaque medium
- opponent channels
- optical radiation
- organic light emitting diode (OLED)
- orientation
- Ostwald color system
- overcast sky
- overhang
- overhead (or butterfly)
- ozone-producing radiation