Template:POTD/2012-01-31
A light microscope image of tissue paper. The tissue was illuminated with ultraviolet light making it glow blue due to natural autofluorescence, the same effect which makes paper glow with a black light. The tangled network of fibres are cellulose fibres which are derived from wood and make up all types of paper and cardboard. It is a combination of the properties of cellulose and additional optical brightening agents which makes the tissue glow.Photo: Richard Wheeler