Changes

===Three-dimensional===

===Three-dimensional===

{{main|Three-dimensional printer}}

{{main|Three-dimensional printer}}

3D printers are a new technology that enables users to print a solid object using a variety of materials.  Just as a ink jet printer can be used to deposit an ink or marking substance on a flat piece of paper, similar mechanisms can be used to deposit a bulky substance instead.  As such substances cure, they can accumulate to form a three dimensional object. As the printer makes repeated passes over the object the pattern of depositing the substance can change, which will affect the ultimate shape of the object.  To use this type of printer a user creates a 3D model on a computer, then sends the job to the printer.  The printer then constructs the object on a mat, by moving the nozzle (or print head) on a dual-axis assembly and releasing small amounts of the material where it is needed. In general, these printers are very slow in comparison to 2D printers, but the technology is still evolving and improving significantly.  These are used in private, educational, manufacturing, medical, and other venues.

3D printers are a new technology that enables users to print a solid object using a variety of materials.  Just as an ink jet printer can be used to deposit ink or a  marking substance on a flat piece of paper, similar mechanisms can be used to deposit a bulky substance instead.  As such substances cure, they can accumulate to form a three dimensional object. As the printer makes repeated passes over the object the pattern of depositing the substance can change, which will affect the ultimate shape of the object.  To use this type of printer a user creates a 3D model on a computer, then sends the job to the printer.  The printer then constructs the object on a mat, by moving the nozzle (or print head) on a dual-axis assembly and releasing small amounts of the material where it is needed. In general, these printers are very slow in comparison to 2D printers, but the technology is still evolving and improving significantly.  These are used in private, educational, manufacturing, medical, and other venues.

===Virtual===

===Virtual===

===Laser===

===Laser===

The laser printing method uses a laser to "paint" the desired image onto a photosensitive imaging drum. Toner is then picked up by the drum, and transferred to the paper.  Heat an pressure are then applied to the paper to fuse the plastic-based toner to the sheet. Black printer one go through this process once, but color printer must do so four times.  There are four photoreceptive drums, one is used for each color--yellow, magenta, cyan, and black.  Each drum prints its color onto a belt, then a transfer roller moves the toner to the paper.<ref name="escotal.com">http://www.escotal.com/printer.html</ref> The printing process is as follows:

The laser printing method uses a laser to "paint" the desired image onto a photosensitive imaging drum. Toner is then picked up by the drum, and transferred to the paper.  Heat an pressure are then applied to the paper to fuse the plastic-based toner to the sheet. Black printer one go through this process once, but color printer must do so four times.  There are four photoreceptive drums, one is used for each color—yellow, magenta, cyan, and black.  Each drum prints its color onto a belt, then a transfer roller moves the toner to the paper.<ref name="escotal.com">http://www.escotal.com/printer.html</ref> The printing process is as follows:

#Processing: Construct the page in memory

#Processing: Construct the page in memory

#Charging: Put an negative electrostatic charge on the imaging drum

#Charging: Put an negative electrostatic charge on the imaging drum