| 摘要 |
A lighting device for stimulating plant growth comprises at least one solid state light source, suitable for emitting light of at least one wavelength within a predetermined wavelength range. The at least one solid state light source is adapted for connection to an electrical network, and the at least one solid state light source is in contact with a cooling medium, and the lighting device is further provided with a first tube, at least part of it being transparent for light from a predetermined wavelength range. The at least one solid state light source is positioned in the first tube. The cooling medium has a temperature in a temperature range between -50 and 00C. The lighting device is further provided with a third tube with a smaller diameter than the first tube and is positioned such that it is enclosed by the first tube. The third tube is a metal tube suitable for receiving the cooling medium and is provided with a supply opening and a discharge opening for respectively supplying and discharging the cooling medium and wherein the at least one solid state light source is positioned in contact with the third tube between the first and the third tube. |
