title: Irradiance and spectral distribution control system for controlled environment chambers.
abstract: This paper describes a closed-loop control system for controlling the irradiance and spectral quality generated by fluorescent lamps in a controlled environment chamber.  The 400 to 800 nm irradiance and the ratio of the red waveband (600 to 700 nm) to the far-red waveband (700 to 800 nm) were independently controlled and varied as functions of time.  A suggested application is to investigate the possibility of synergistic effects of changing irradiance levels and changing spectral distributions on photoperiodism and photomorphogenesis.
authors.affiliation: Smithsonian Environmental Research Center, Rockville, MD 20852, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Krones
authors.forename: J C
authors.initials: JC
authors.lastname: Sager
authors.forename: A T
authors.initials: AT
authors.lastname: Johnson
mesh_terms: D003199:Computer Systems; D004780:Environment, Controlled; D004867:Equipment Design; D008021:Life Support Systems / Q000295:instrumentation; D008027:Light; D008029:Lighting; D017440:Photoperiod; D013057:Spectrum Analysis