Epson LQ-2550 User Manual - Page 119

Because the dots overlap each other both horizontally and vertically in the Letter Quality mode, it is difficult to see individual dots. Instead, the letters and symbols seem to be made of unbroken lines. In order for the dots to overlap vertically, the pins are in more than one column, but the intelligence of the printer handles the timing of pin firings so that the effect is of 24 pins arranged in a single vertical column. Dot patterns Your printer's print head is able to print graphics as well as text because graphic images are formed on the printer about the same way that pictures in newspapers and magazines are printed. If you look closely at a newspaper photograph, you can see that it is made up of many small dots. Your printer also forms its images with patterns of dots, as many as 360 dot positions per inch horizontally and 360 dots vertically. The images printed by the printer can, therefore, be as finely detailed as the ones at the beginning of this section. Color graphics With the color ribbon and appropriate software, you can print in a wide variety of colors. Even if your software doesn't support color, printer command ESC r lets you select from seven basic colors, including black. In addition, you can combine some of the basic colors for a greater variety. 4-14 Using Software and Graphics