Light Source For Plant Cultivation

What is this patent about?

’509 is related to the field of plant cultivation, specifically light sources designed to optimize plant photosynthesis. Traditional plant lighting solutions, such as incandescent and fluorescent lamps, often fail to provide the specific wavelengths needed for efficient photosynthesis. More recent LED-based solutions can be limited by narrow spectrums or excessive energy consumption, leading to suboptimal plant growth and increased costs.

The underlying idea behind ’509 is to create a light source that more closely matches the McCree curve , which represents the optimal wavelengths for plant photosynthesis. This is achieved by combining multiple light sources with different spectral peaks and sub-peaks within the photosynthetically active radiation (PAR) range (400-700 nm). The key is to strategically position these peaks and sub-peaks to fill in the gaps and valleys in the combined spectrum, resulting in a more uniform and efficient light source for plant growth.

The claims of ’509 focus on a light source comprising a substrate with at least two light sources: a first light source emitting a light with a peak between 400-500nm and a sub-peak with a wider full-width at half-maximum, and a second light source emitting a light with a peak between 500-700nm. Crucially, the intensity of the second peak must be greater than the intensity of the first sub-peak. The spectral positions of the first sub-peak and the second peak are different, and the combined light spectrum exhibits distinct valleys that do not overlap, ensuring light delivery in those regions.

In practice, the first light source could be a white LED with a blue peak and a broader sub-peak in the green-yellow range, while the second light source could be a red LED. By carefully selecting the wavelengths and intensities of these light sources, the combined spectrum can be tailored to closely match the McCree curve. The controller allows for independent adjustment of the light sources, enabling customization based on plant type and growth stage.

This approach differs from prior solutions that rely on single-wavelength LEDs or simple combinations of white and red light. By strategically combining light sources with complementary spectral characteristics, ’509 aims to provide a more complete and balanced light spectrum for plant photosynthesis. The non-overlapping valleys in the combined spectrum are a key feature, ensuring that plants receive sufficient light across the entire PAR range, leading to improved growth rates and reduced energy consumption. The use of multiple light sources with different spectral peaks allows for a more tailored and efficient light source compared to traditional methods.