Matsushita Electric Industry's most elaborate bright white LED module development process

"For mass production, the difficulty of solving the heat problem has been quite large" (Matsushita Electric lighting business LED special products and new market development center under the director of the husband). Matsushita, before successfully developed a white light emitting diode reached the highest level in the industry in the field of brightness of lighting equipment (LED) module. By the "Tokyo International Lighting Fair" in March 1, 2005 in Tokyo BigSight International Convention and Exhibition Center opened in the vicinity of the conference held a product launch. At the meeting, there was a similar spherical shape of incandescent lamp, fluorescent lamp, and the practical application of this module, such as a piece of paper in the shape of the luminous surface, which fully demonstrated the technical strength of the company. However, in order to release the product, the company has been working hard to solve the technical problems of high power white LED. The release of the module used in the packaging technology, in fact, as early as August 2003 has been published. For example, in order to avoid the influence of light on the route, as the blue LED chip light source package by flip chip; in order to control the white light is not stable, and the blue LED chip with fluorescent materials used were designed with thin film; in order to improve the heat dissipation, the copper plate and the ceramic package etc. that is exactly the same with the technology of the time. However, in order to reflect the actual product in the general user's impression of LED has a longer life than incandescent and fluorescent lamps, this alone can not do the. As the module used by the blue LED chip, each chip assigned to the power of up to 1W or so, than in the small LCD panel backlight when used to be higher than 1 digits. Therefore, in the light of the chip heat dissipation is very large, in the past due to the inability to successfully release the heat to the outside of the module, it will lead to packaging materials aging, and then the brightness will decline. Packaging materials have been using short wavelength light resistance and heat resistance of epoxy resin is stronger than silicone, but can not avoid the aging phenomenon. Heat can not be successfully lost in the past can not be successful in the release of the chip heat to the outside of the module, it is said that because the ceramic package and the copper plate is not good enough. The Panasonic electrician's white LED module is the first in the ceramic packaging configuration blue LED chip, and then the ceramic package and copper plate together. Thus, the heat of the chip can be transmitted to the copper substrate through a ceramic package. The company did not disclose the details, it is said that the use of a special material to connect the ceramic packaging and copper base. Not only adhesion has been improved, but even in mass production, the adhesion between the modules will not be unbalanced. The service life can be guaranteed by 40 thousand hours. Although the heat problem has been resolved, but now the module in the 25W power of the beam is only 250lm (lumens) or so. This year, ready to improve the power circuit, etc., to improve the module brightness. This module is about 20% of the amount applied to the AC power supply to the DC power supply in the process of loss. If this part of the optimization, then the power loss can be reduced to about 5%. (source: Nikkei news agency BP)