Oki C 9400 - Manual (Page 339)

Halftoning
Shades of gray can be generated by using a similar method of black dot placement. This
technique is known as halftoning and gives rise to what we perceive as a continuous tone
image.
The entire printing area is split into sections known as cells (much like a grid). The patterns
within the cell are then altered to obtain the required amount of grayscale. An area of an image
containing 50% gray will contain cells that have half of the dots within the cell printed with black
and the other half left empty.
The Electromagnetic Spectrum
Visible Light
Visible light comprises a minute portion of the electromagnetic (EM) spectrum. Although we are
"blind" to the rest of the EM spectrum, the part we do see has a significant impact on our
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