Abstract: A multicolor direct thermal imaging method wherein a multicolor image is formed in a thermal imaging member comprising at least first and second different image-forming compositions and a thermal printer for use in practicing the method. Heat is applied to at least the second image-forming composition while the first image-forming composition is at a first baseline temperature (T1) to form an image in at least the second image-forming composition, and heat is applied to at least the first image-forming composition while it is at a second baseline temperature (T2) to form an image in at least the first image-forming composition, wherein T1 is different from T2.

Abstract: A multicolor direct thermal imaging method and an imaging member for use therein, wherein a multicolor image is formed in a thermal imaging member having at least two different image-forming compositions capable of forming two different colors. Heat is used to form an image in the first color at a first speed of travel of the thermal imaging member with respect to the source of heat, and heat is used to form an image in the second color at a second speed of travel of the thermal imaging member with respect to the source of heat, where the first speed of travel and the second speed of travel are different from each other.

Abstract: A method for controlling the print density of individual heating elements of a thermal print head array determines respective energy values for each heating element in response to image pixel data to be printed, multiplies determined energy values by a respective predetermined correction factor for one or more respective heating elements for improving print density consistency between individual heating elements, and dithers adjusted energy values from the step of multiplying as a function of adjacent image pixels.

Abstract: Techniques are disclosed for performing color correction in a color printer. An RGB test image is printed to produce a printed calibration image. Colors in the printed calibration image are measured and compared to expected color values. A color corrector generates a printer lookup table (LUT) based on this comparison. The LUT may be generated based on models of the printer's print engine and previous LUTs. The color corrections are applied to subsequent print jobs to improve the quality of color output. Color measurement and correction may be performed using a closed-loop system contained within the printer that includes a color measurement device (such as a scanner) and a computer.

Abstract: A multicolor imaging system is described wherein at least two, and preferably three, different image-forming layers of a thermal imaging member are addressed at least partially independently by a thermal printhead or printheads from the same surface of the imaging member by controlling the temperature of the thermal printhead(s) and the time thermal energy is applied to the image-forming layers. Each color of the thermal imaging member can be printed alone or in selectable proportion to the other color(s). Novel thermal imaging members are also described.

Abstract: Techniques are disclosed for performing thermal history control in a thermal printer in which a single thermal print head prints sequentially on multiple color-forming layers in a single pass. Each pixel-printing interval may be divided into subintervals, which may be of unequal duration. Each sub-interval may be used to print a different color. The manner in which the input energy to be provided to each print head element is selected may be varied for each of the subintervals. For example, although a single thermal model may be used to predict the temperature of the print head elements in each of the subintervals, different parameters may be used in the different subintervals. Similarly, different energy computation functions may be used to compute the energy to be provided to the print head in each of the subintervals based on the predicted print head temperature.