Canon BJC-5000 Service Manual

Also see for Color Bubble Jet BJC-5000 Series: Parts catalog User manual

4-11BJC-5000Part 4: Technical Reference2.2 Printing SystemControl functions are provided by conventional printers. In this printer, however, thesecontrol functions are mostly processed by the printer driver of the host computer.With conventional printers, image data in the raster direction (horizontal direction data)is created on the printer driver and the printer side receives this data. Consequently,the image data in raster direction received by the printer is converted into column data(vertical direction data) by the printer and the printing is executed.The printer driver on the host computer handle all processes until the creation ofcolumn data matching the printhead installed in the printer. Then, the printer receivesthis column data and prints it. (The printer reads the printhead ID and automaticallynotifies the host computer of the printhead configuration.) Thus, this printer achieveshigh speed printing because it does not need to convert raster data into column dataand can print the data as it is.2.3 Printing Modes2.3.1 Printing modeThis printer varies the printing method, such as carriage movement and bubble jethead driving frequency, in accordance with the cartridge installed, the selectedmedium, the selected printing mode, the resolution, and the print data in order toachieve high-quality printing without any bleeding or shifting in the printout.When color printing is performed using a single pass, the different colors printed atthe same time overlap, often causing the colors to run. By printing with two or moredelayed passes, there is less color bleeding because the color printed immediatelybefore is relatively stable by the time the next color is printed over it.When print data is processed internally by the printer, the data is recognized and thenumber of ink nozzles to be used by the black ink is automatically changed.Characters are printed by taking preventive measures for bleeding and white mistwhich are generated at the borders because the characteristics of the color and blackinks differ. This process is carried out as follows: During internal processing by theprinter, the borders where the color and black inks meet are identified. Cyan andblack ink are mixed in the printed black portion to suit the distance and density ofthe black and color dots.2.3.2 Photo print modeThe photo print mode can be used to obtain a print quality with rich gradation thatreduces granularity by printing several times on the same dot using the Photo BJcartridge which contains a light density ink.The printer driver divides the pixel data into 4 values (not printed, print 1 dot, print 2dots, and print 3 dots) enabling each pixel to be printed using up to 4 gradations.When the color cartridge and photo auto cartridge are installed, high-quality print isachieved by using 7 types of inks (cyan, magenta, yellow, black, photo cyan, photomagenta and photo black). In addition, an improved gray color reproduction has beenprovided by the use of 2 types of black inks.2.3.3 Multi-drop print modeThe color cartridge uses drop modulation technology to print large and small dotsefficiently so that the granularity of low density portions can be reduced. The photocartridge of this machine prints small dots only.