The knowledgebase is a tool to help you build a knowledgebase. It is organized into various topics. Users ask questions pertaining to certain topics. The questions/answers are browsable by keywords. The data is stored in a relational database. You need to have Apache with PHP3 and MySQL to use this tool.
KOJAC is a set of Java classes implementing optical elements and optics laws in order to build and simulate optical systems. It is also aimed at being a demonstrator of optics for educational purposes. Optical systems are composed of objects with defined properties that may be modified by the user through the applet's buttons and scrollbars. Such basic devices are lenses, apertures, interfaces, and may be themselves composite sets of other elements. KOJAC is able to do exact raytracing in 3 dimensions, taking into account the wavelength of the rays, and simulating real materials.