Light Sources and Lighting Circuit (2009)

According to the machinery statistics by METI, the total number of domestic light bulb production in 2008 was 901 million (91.0% y/y), of which 83 million accounted for general lighting purpose light bulbs (75.6% y/y) and 40 million for halogen lamps (90.9% y/y). The total number of fluorescent lamps produced was 861 million (93.8% y/y). For general-purpose fluorescent lamps excluding backlights, the total production was 279 million (89.9% y/y). The total number of HID lamps produced was 10 million (100.7% y/y). In terms of sales amount against the previous year, general lighting purpose light bulbs was 88.3%, halogen lamps 91.8%, general-purpose fluorescent lamps 100.5%, backlights 82.2%, and HID lamps 97.8%. Within general-purpose fluorescent lamps, the sales amount of bulb-type fluorescent lamps was 13.7.3% y/y. The movement of replacing incandescent lamps has further accelerated, triggered by the policy set forth at the G8 Summit in Toyako, namely to ban the use of incandescent light bulbs. Several exhibitions were held in 2008. Domestic events include, “ Special Exhibition: ‘LED Next Stage’ ” held in conjunction with “ Japan Shop 2008” in March, and “ LED Japan 2008” in October. As for overseas events, a trade show “ Light + Building 2008” was held in Frankfurt, Germany in April. In the area of incandescent lamps, many products designed to replace conventional incandescent lamps with halogen lamps were launched by overseas manufacturers. Development in bulb-type fluorescent lamps, as well as technological advancement in longer life for general fluorescent lamp products, continued to be active. Special editions featuring studies on electrodes were issued by various academic journals. Although the cost per unit luminous flux remains to be high, LED light sources are today on par with conventional light sources (also with fluorescent lamps) in terms of light-emitting efficiency. Development in bulb-type LED products is becoming more vigorous. Progress in technologies for LED chips is robust and improvement in light-emitting efficiency is remarkable. On the other hand, credibility assessment for LED products including life prediction is proactively being reviewed in response to the high expectation toward a long product life exceeding tens of thousands of hours. For HID lamps, product/technology research and development on ceramic metal halide lamps continue to be dominant. A number of fundamental studies based on experiments and modeling schemes was carried out with respect to product development, namely improving light-emitting efficiency, color rendition and product life. The future challenges for HID lamps include gaining further knowledge on filler gases, material behaviors, and the discharge phenomenon. In the area of other discharge lamps, the majority of reports presented were on inductively coupled electrode-less lamps with mercury, microwave discharge lamps, and excimer discharge lamps. There were also reports on new discharge light sources based on nanotechnology application. Several lighting circuit structures for discharge control were proposed for fluorescent lamps, HID lamps, and electrode-less lamps. For lighting circuits for LED, simple circuit structures to achieve miniaturization and cost reduction were introduced in many reports.