Previous means of producing a prototype typically took man-hours, many tools, and skilled labor. For example, after a new street light luminaire was digitally designed, drawings were sent to skilled craftsmen where the design on paper was painstakingly followed and a three-dimensional prototype was produced in wood by utilizing an entire shop full of expensive wood working machinery and tools. This typically of solid printing technology was not a speedy process and costs of the skilled labor were not cheap. Hence the need to develop a faster and cheaper process to produce prototypes. As an answer to this need, rapid prototyping was born: that is 3D printer.
One variation of 3D printing consists of an inkjet printing system. Layers of a fine powder are selectively bonded by "printing" an adhesive from the inkjet printhead in the shape of each cross-section as determined by a jpeg file. This 3D printing technology is the only one that allows for the printing of full colour prototypes. Solid color printing is also recognized as the fastest method.
Alternately, these machines: 3D printer feed liquids, such as photopolymer, through an inkjet-type printhead to form each layer of the model. These Photopolymer Phase machines use an ultraviolet flood lamp mounted in the print head to cure each layer as it is deposited.
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