How Inkjet Colour Printers Work
Nearly everyone that has a computer in the home these days has an Inkjet printer attached to it but not many of use knows how the text on the screen or the colour photo that you have taken with your digital camera gets printed out on the paper that feeds through your inkjet printer.
Producing a colour image on inkjet on inkjet paper is far different than producing the image on the monitor. A computer monitor uses the primary additive colours mainly red green and blue. This is because is because when light represented by each of these colours is added, the eye perceives almost any other colour if the RGB components are mixed in the right components are mixed in the right proportions. When looking at a picture on inkjet paper or any other paper, a very different mechanism is used. Light does not emit from the paper here we see the image by a reflection of ordinary light e.g. sunlight from the page. The material on the page absorb parts of the white light and the eye preserves what ever colours are reflected after the others have been absorbed. Making use of these facts, inkjet printers have developed a model called CYM based on the three subtractive primary colours called cyan, magenta and yellow.
Using cyan, magenta and yellow inks it is possible to create other colours. For example cyan and yellow makes green and mix all three together creates black or none at all makes white assuming that you are printing on white inkjet printer paper. In addition to those base colours, by using clever combinations of masses of dots printer close together, an optical illusion is created and the eye is fooled into thinking it is observing a continuous colour of different hue. A less saturated red could be made up from red dots with an increasing amount of white space in between them. The effect would make the eye preserve this colour as pink.
Although black in theory is made up by mixing all three colours together in practice it has been found to get better and sharper quality to have black added as an additional colour. Just like you have in a black and white inkjet printer today. So a new model had to be developed this new model was called CMYK cyan, magenta, yellow and key or black has been developed for best results. It is this model that is used in modern day inkjet printers. The CYMK model is also used as the basis for 32-bit colour graphics.
The above is the theory on how an inkjet printer works. The above theory is also used in colour laser and solid ink printers.
Now in the high end inkjet printers the manufacturers are starting to use half colour shades to give even better image quality so that you can get just as good photo prints from your inkjet printer as you would from getting your digital images processed at a photo laboratory. Thus bring down the total cost of owner ship of a digital camera.
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