Multielement Selective Emitter

The proposed research is directed at demonstrating the feasibility of a new type of grow lamp. Based on incandescent light generation, it potentially provides a much more sun-like spectral distribution than what is possible with HID or other lamps. The innovation is based on structuring a ceramic oxide to emit much more efficiently at shorter wavelengths than rungsten, thereby shifting its emission spectrum to closely resemble that of natural sunlight. Prior work at lower temperatures demonstrated the predicted shift in the spectrum, and the current proposal is directed at demonstrating a similar shift at the expected 2650 K operating temperatures. Although, for the same input power, the incandescent emitter is expected to generate less total PAR power than HID lamps, its spectral intensity distribution is strong in both the short and long wavelength absorption regions of chlorophyll a and b such that the resulting photosynthesis rate is 30% greater than that of MH grow lamps and 43% greater than that of HPS lamps. Compared with a standard incandescent bulb, the proposed emitter generates much less infrared radiation and is thermally insulated from its glass enclosure by a high vacuum, therefore it burns much cooler. Demonstrating the feasibility of a novel method of heating the emitter is also a goal of the proposed work. In addition to a more sun-like spectrum than other lamps, the proposed lighting will need no external ballast, making it simpler and significantly less expensive to manufacture.