CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims benefit of priority under 35 USC § 119 to Korean Patent Application No. 10-2019-0131890 filed on Oct. 23, 2019 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

1. Field

The present disclosure relates to a light emitting device and a light apparatus for plant growth.

2. Description of Related Art

As a cultivation method to reduce an uncertainty in food production, due to factors such as climate change, protected crop production in a facility such as a greenhouse or a plant factory is actively increasing in order to reduce or minimize an influence of an external climate and to stably produce food. Such protected crop production not only enables continuous production throughout the year through environmental management, but also improves crop yield and/or quality thereof.

In protected crop production, it may be important to secure light for plant growth since a greenhouse or a plant factory cannot directly use sunlight.

As a method for securing sufficient light for plant growth, artificial light such as light from a light emitting diode (LED) has been in the spotlight. Such LED lighting may not only have sufficient light efficiency, but may also allow for the selection of a specific desired wavelength of light, which are advantages that can be realized with a miniature lighting device.

SUMMARY

An aspect of the present disclosure is to provide a light emitting device capable of ensuring efficient photosynthesis through light penetration while satisfying an absorption spectrum for plant growth.

Another aspect of the present disclosure is to provide a light apparatus for plant growth capable of ensuring efficient photosynthesis through light transmission while satisfying an absorption spectrum for plant growth.

According to an aspect of the present disclosure, a light emitting device for plant growth includes a blue light emitting diode (LED) configured to emit blue light, and at least one wavelength converting material configure to be excited by the blue light and convert a portion of the blue light into converted light having a different wavelength, the converted light being light for plant growth. An emission spectrum of the light for plant growth is when a photosynthetic photon flux (PPF) of a 400 nm to 500 nm band is 1, a PPF of a 500 nm to 600 nm band is in a range of 6 to 10, and a PPF of a 600 nm to 700 nm band is in a range of 5 to 7.

According to an aspect of the present disclosure, a light emitting device for plant growth includes a blue light emitting diode configured to emit blue light having a dominant wavelength in a range of 430 nm to 470 nm; a first wavelength converting material configure to be excited by the blue light and emit light having a peak wavelength in a range of 490 nm to 580 nm; and a second wavelength converting material configure to be excited by the blue light and emit light having a peak wavelength in a range of 620 nm to 660 nm. Light for plant growth is emitted by mixing the blue light with the first and second light, an emission spectrum of the light for plant growth is when a photosynthetic photon flux (PPF) of a 400 nm to 500 nm band is 1, a PPF of a 500 nm to 600 nm band is in a range of 6 to 10, a PPF of a 600 nm to 700 nm band is in a range of 5 to 7, and the light for plant growth has an x coordinate in a range of 0.3531 to 0.4939 and a y coordinate in a range of 0.4150 to 0.5665 in a CIE 1931 color coordinate system.

According to aspect of the present disclosure, a light apparatus for plant growth includes a circuit board; and a plurality of white light emitting devices mounted on the circuit board. The plurality of white light emitting devices include a blue light emitting diode (LED) configured to emit blue light, and at least one wavelength converting material configure to be excited by the blue light and convert a portion of the blue light into converted light having a different wavelength, the plurality of white light emitting devices including a plurality of first light emitting devices configured to emit light for plant growth. An emission spectrum of the light for plant growth is when a photosynthetic photon flux (PPF) of a 400 nm to 500 nm band is 1, a PPF of a 500 nm to 600 nm band is in a range of 6 to 10, and a PPF of a 600 nm to 700 nm band is 5 to 7.

