Multicolor LED lamp for use in plant cultivation, illumination appratus and plant cultivation method

摘要

In an illumination apparatus for plant growth using LEDs, a light source emitting mixed color light of red and blue is dominant light source. However, actually, the luminescence intensity of red light is weaker than that of blue light, and the color is adjusted by the number of lamps used. Thus, a small number of blue LEDs are interspersed among a large number of red LEDs, and there is a problem in that it is not possible to make irradiation of blue light uniform. The present invention provides a multicolor light emitting diode lamp in which a blue LED and a AlGaInP-based red LED having high luminescence efficiency, balancing with the blue LED are mounted in the same package. The red LED includes a light emitting section including a light emitting layer having a composition formula, (Al X Ga 1-X ) Y In 1-Y P (0‰¤X‰¤1 and 0Y‰¤1). The red LED emits at least as many photons as the blue LED when the same electric current is flowed. For example, when a strong red light is desirable for plant growth, by mounting two red LEDs and one blue LED, a desired mixed color is obtained with one lamp, and irradiation of light can be made uniform.