This article gives an overview to the special topic, "How to plan LED illuminations appropriately". To begin with, it makes references to the history of the illuminations before the emergence of LED illuminations, significance of the LED illuminations, and the development of the white LED. Then, the article explains about roles in and approaches to illumination planning, such as colors and color rendering of the light, illumination planning and spatial distribution of luminous intensity, the light-emitting sources and the luminance, installations and LED luminaires, and safety and maintenance.

View full abstract

In order to save energy, there is increasing opportunities for purchasing LED illumination products as an alternative to existing luminaires or lamps. Although various manufacturers provide attractive lines of products, there have been some cases reported that product installations did not meet expectation. Therefore, as a reference, this article provides a guideline one should check against before installing an LED illumination products.

View full abstract

LED luminaies are already used for base lighting. Therefore, in this paper, We described about the consideration points of lighting design (illuminance calculation, sensation of space brightness, color rendering properties, circadian rhythm) when LED lighting are adopt.

View full abstract

Differences in lighting effects are explained when incandescent lamps, self-ballasted compact fluorescent lamps and self-ballasted LED lamps were fitted in typical luminaires of home use.

View full abstract

As the expectation put on LED lighting fixtures had been extremely positive, in deed their efficiency has been improved vigorously in one year. The trend to seek high efficiency would probably continue, but it is important not to become a supremacist on energy saving. We should go through the same steps as what has been studied through conventional fixtures, for instance illuminance, brightness sensation, and quality of lighting to create a good ambience of lighted space. On top of that, LED's feature such as its stable efficiency in dimming control would be its advantage for energy saving and physically small size would enable a different form of lighting to improve brightness sensation and quality of lighting.

View full abstract

White LED is an original technology of our country. It is attracting much attention as "the fourth light source". This article discusses current LEDs and challenges in LEDs, which are now facing a turning point in the history of the illuminations. Taking advantage of the characteristics of LEDs, outputs and luminous efficacy have been improved, and LEDs quickly come to be adopted increasingly as indoor lighting, such as those for business space and residences. LEDs have become popular in applications for general illuminations, but there are some remaining challenges that need to be solved before LEDs are further adopted. Such challenges include improvement in comprehensive luminous efficacy, improvement in reliability, improvement in quality of light, compliance to regulations, understanding of and communication about performance, researches for illumination adaptability, enhancement of standardization, and application development.

View full abstract