PAR and Plant Response Curve
Plants need balanced, full-spectrum light for good health and optimum growth. The quality of light a plant receives is just as important as the quantity. Plants are sensitive to a similar portion of the spectrum as is the human eye. This portion of the light spectrum is referred to as Photo-synthetically Active Radiation or PAR, namely the wavelength spectrum of about 400 to 700 nanometres.
LIGHT TRANSMISSION THROUGH GREENHOUSE COVERS
When light “strikes” the greenhouse cover, a number of things might happen to the light wave.
• It could be absorbed by the film, in which case its energy is converted into heat.
• It could be reflected by the film.
• It could be transmitted by the film. There are two types of transmission: direct or diffused.
1. Direct transmission (clear film):
Occurs when light penetrates the film and its direction remains unchanged. Films with direct transmission have the highest light transmission, this directional and intense light creates shadows and burning rays.
2. Diffuse transmission (translucent film):
Light diffusion is achieved simply by scattering light waves. A small intense beam of light scatters and disperses light waves across a wider area. Scattered light comes from many directions rather than from a single point of origin. The sun’s direct rays turn into diffused light avoiding all direct transmission dis advantages.
Light diffusion is achieved by adding mineral to the greenhouses covers, the standard diffusion agent and because of their chemistry, absorb part of the light, thus, the total light transmission is reduced. The Diamond 15 was developed to combine light transmission as the clear films and light diffusion without reducing the light transmission. As shown in the following spectrum films based on this technology has the same light transmission as clear film light transmission,
Also, Diamond 15 films have higher thermicity comparing to the standard film in the market,
Films based on Diamond 15 technology can contain also anti-fog, anti-mist, anti-virus and all other know greenhouses cover properties.