outlets. Cathodoluminescence is used in cathode ray tubes, photoluminescence in fluorescent lighting and plasma display panels, phosphorescence in safety signs and low energy lighting, fluorescence in pigments, inks, optical brighteners, safety clothing, and biological and medicinal analysis and diagnostics, chemoluminescence and bioluminescence in analysis, diagnostics and sensors, and electroluminescence in the burgeoning areas of light-emitting diodes (LEDs/OLEDs), displays and panel lighting. Important new developments are taking place in the areas of quantum dots and metallic nanoparticles. Light and energy transfer Absorption of light and energy transfer (or conversion) involves colored molecules that can transfer electromagnetic energy, commonly in the form of a laser light source, to other molecules in another form of energy, such as thermal or electrical. These laser addressable colorants, also called near-infrared absorbers, are used in thermal energy conversion, photosensitisation of chemical reactions and the selective absorption of light. Applications areas include optical data storage, as organic photoconductors, as sensitisers in photomedicine, such as photodynamic therapy and photothermal therapy in the treatment of cancer, in photodiagnosis and phototheranostics, and in the photoinactivation of microbes, blood and insects. The absorption of natural sunlight by chromic materials/chromophores is exploited in solar cells for the production of electrical energy via solar cells, using both inorganic photovoltaics and organic materials (organic photovoltaics) and dye sensitized solar cells (DSSCs), and also in the production of useful chemicals via artificial photosynthesis. A developing area is the conversion of light into kinetic energy, often described under the generic term of lightdriven/molecular machines. Light manipulation Materials may be used to control and manipulate light via a variety of mechanisms to produce useful effects involving color. For instance, a change of orientation of molecules to produce a visual effect as in liquid crystal displays. Other materials operate by producing a physical effect, by interference and diffraction as in lustre pigments and optically variable pigments, colloidal photonic crystals and in holography. Increasingly inspiration is coming from Nature, in the form of bioinspired structural colors. Molecular materials are also used to increase the intensity of light by modifying its movement through the materials by electrical means, so increasing its intensity as in organic lasers, or in modifying the transmission of light through materials, as in opto-electronics, or by purely by all optical means as in optical limiters. References Bibliography Bamfield Peter and Hutchings Michael, Chromic Phenomena; technological applications of colour chemistry, 3rd Edition, Royal Society of Chemistry, Cambridge,