| 摘要 |
PURPOSE:To efficiently irradiate plants with light rays suitably to growth rate of plants and to grow plants with saved electric power, by controlling intensity of light rays through a regulator in such a way that average light quantum numbers of photosyntheses in continuous illumination time and intermittent illumination time become specific values. CONSTITUTION:Culture plants 3 are arranged in a plant growth device 1 and illuminators 2 having discharge lamps 7 such as fluorescent lamps 7 are set at the upper part. Then a DC electric source 4 for a regulator connected to the discharge lamps 7 is sent and a high-frequency electric source 5 consisting of a coil 51, transistors 52 and 53, base resistances thereof 54 and 55, a condenser 56, an output transformer 57, a secondary winding thereof 58 and a feedback winding 59 is subjected to self- oscillation to generate high-frequency output voltage. When a transistor 62 of an intermittent control part 6 consisting of a full-wave rectifier 61, a transistor 62 and a drive circuit 63 is in on state in the operation, the lamps 7 are lighted and illuminate the plants and when the transistor is in off state, the lamps are suspended. For example, at a short-time period of 1-50ms, intermittent illustration is carried out by regulating average light quantum numbers E0 and E1 of photosyntheses in continuous illumination time and intermittent illumination time E0>=110muEm<-2>s<-1> and E1>=80muEm<-2>s<-1>, respectively. |
