By Takashi Nakagaw
Metamerism is a phenomenon in which colors of two objects appear the same under a lighting condition while they appear different under another lighting condition. Since metamerism have caused troubles among manufacturers and consumers, it is desirable to develop lighting apparatus to produce various lighting conditions. The author reports that we can make such lighting apparatuses using LEDs. An easy way is to use power LEDs which are provided in packages easy to handle. However, they are not always sufficient due to inadequate color variety. More satisfactory apparatuses can be made using deep red, red, amber, green, cyan, blue, and purple (royal blue) chip LEDs. However, chip LEDs need to be handled with care. The author shows jigs and ways to fabricate lighting apparatus with chip LEDs, and demonstrates amazing metamerism.