Abstract: A printing system using a thermal printer capable of readily visually discriminating the background data and sales data, saving waste of paper resources and improving the printing speed is provided. When printing basic data and background data in superimposition on each other in a thermal printer having a matrix array of color generation dots, data representing density gradation values are supplied to each color generation dot for printing background data with density lower than the density of the basic data. The direction of the basic data is set to a direction different by 90 degrees, for instance, from the direction of the array of the basic data. The visual discrimination of the two different kinds of data is improved.

Abstract: A system for printing data on sheets, which can solve the problem of the waste of paper resources and also improve the printing speed. The second data is printed as background on an area of printing the first data in a mode that the first and second data can be visually discriminated from each other. The sheets are either receipts or train tickets or airplane tickets or entrance tickets. The mode permitting the visual discrimination is one based on density gradation printing. The printing is performed by a thermal printer. The mode permitting the visual discrimination is one based on the difference in density.

Abstract: A printing system using a thermal printer capable of readily visually discriminating the background data and sales data, saving waste of paper resources and improving the printing speed is provided. When printing basic data and background data in superimposition on each other in a thermal printer having a matrix array of color generation dots, data representing density gradation values are supplied to each color generation dot for printing background data with density lower than the density of the basic data. The direction of the basic data is set to a direction different by 90 degrees, for instance, from the direction of the array of the basic data. The visual discrimination of the two different kinds of data is improved.

Abstract: A gradation control system includes a device for deriving 2**n decoded data from lower n bits expressing a gradation per dot, a device for grouping the 2**n decoded data with respect to a plurality of dots, to produce 2**n first bit planes, a device for giving to an element a signal of pattern corresponding to each of the first bit planes for a time obtained by adding a time that depends on a decoded value of each of the first bit planes, to an initializing time, a device for grouping, per bit weight, respective bits excluding the lower n bits that express the gradation per dot, to produce a second bit plane, and a device for giving to the element a signal of pattern corresponding to the second bit plane for a time that depends on a weight of the second bit plane.

Abstract: A system for printing data on sheets, which can solve the problem of the waste of paper resources and also improve the printing speed. The second data is printed as background on an area of printing the first data in a mode that the first and second data can be visually discriminated from each other. The sheets are either receipts or train tickets or airplane tickets or entrance tickets. The mode permitting the visual discrimination is one based on density gradation printing. The printing is performed by a thermal printer. The mode permitting the visual discrimination is one based on the difference in density.

Abstract: A gradation control system includes means for deriving 2n decoded data from lower n bits expressing a gradation per dot, means for grouping the 2n decoded data with respect to a plurality of dots, to produce 2n first bit planes, means for giving to an element a signal of pattern corresponding to each of the first bit planes for a time obtained by adding a time that depends on a decoded value of each of the first bit planes, to an initializing time, means for grouping, per bit weight, respective bits excluding the lower n bits that express the gradation per dot, to produce a second bit plane, and means for giving to the element a signal of pattern corresponding to the second bit plane for a time that depends on a weight of the second bit plane.