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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- paddle
- panel face exit sign
- pantograph
- PAR lamp
- par light
- parabolic spotlight
- parallel (television, film, theater)
- parking lamp
- partial diffusion
- partly cloudy sky
- passing beams
- patch
- patch panel
- pattern spotlight
- peak wavelength (λp)
- pendant luminaire
- perceived chroma of an area of surface color
- perceived color
- perceived light source color
- percent flicker
- perfect diffusion
- perimeter lights
- period life
- peripheral vision
- peripheral visual field
- personal tuning
- phantom
- phosphor mercury lamp
- phosphorescence
- phot-
- phot
- photobiological hazard
- photobiological (human) hazard function
- photobiology
- photocarcinogenesis
- photocataractogenesis
- photochemical radiation
- photochemotherapy
- photoconjunctivitis
- photocontrol
- photocuring
- photodynamic therapy
- photoeffect
- photoflash lamp
- photoflood lamp
- photokeratitis
- photokeratoconjunctivitis
- photometer
- photometric brightness
- photometry
- photomorphogenesis
- photomutagenesis
- photon
- photon flux maintenance
- photon flux (Φp)
- photoperiod
- photoperiodism
- photopic vision
- photoretinitis
- photosensitization
- photosynthesis
- photosynthetic irradiance
- photosynthetic photon flux density (PPFD)
- photosynthetically active radiation (PAR)
- phototaxis
- phototherapy
- phototropism
- physical photometer
- physical receptor
- pigtail
- pilot house control
- pin plug or connector
- pipe
- Planck radiation law
- Planckian locus
- plano-convex spotlight
- plate
- plot
- point brilliance, E
- point-by-point method
- point method
- point of fixation
- point of observation
- point source
- point vision
- polarization
- polarized radiation
- pole
- portable lighting
- portable luminaire
- portable traffic control light
- position index, P
- position lights
- practical lamp (television, film and theater)
- pre-burning time
- prefocus lamp
- preheat (switch start) fluorescent lamp
- preset
- pressed reflector lamp
- primary color