Technique for printing a color image

Abstract

A technique for optimizing or enhancing color images. Embodiments are disclosed for creating an enhanced color image, including the enhancement of perceived color uniformity. In a “dot-on-dot” registration scheme for producing color images, the dots need to be precisely superimposed on each other to provide optimum or enhanced images. The dot-on-dot registration produced by a single head thermal printer is generally acceptable, but a single head machine is very slow because multiple passes (reciprocation) are required to lay down multiple colors of dots. In a much faster multi-head or tandem thermal imaging system a serious problem of dot misalignment may cause more patterns or other visual artifacts in the color images produced by dot patterns. A solution to this problem is disclosed herein which intentionally misregisters superimposed dots in a novel and particular manner to achieve image optimization.

1 . A system for creating a color image on a physical medium having a planar surface using a plurality of dot patterns, the planar surface having first and second orthogonal spatial dimensions, each one of the dot patterns being monochromatic and different in color from the color of each other of the dot patterns, the physical medium being movable in a first direction parallel to the surface, the system comprising:
 first means for creating a first colored dot pattern on the surface of the physical medium, the first colored dot pattern having a first color, the dots forming the first colored dot pattern being spaced at first predetermined distances from each other;   second means for creating a second colored dot pattern on the surface of the physical medium, the second colored dot pattern having a second color, the dots forming the second colored dot pattern being spaced at second predetermined distances from each other, wherein at least one of the dots forming the second colored dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern; and   means for controlling the first predetermined distances and the second predetermined distances to result in a particular intentional misregistration pattern between the dots of the second colored dot pattern and the dots of the first colored dot pattern;   wherein the first and second dot patterns each comprise a plurality of dots being randomly spaced on the surface of the physical medium in the first dimension and being regularly spaced on the surface of the physical medium in the second dimension.   
     
     
         2 . The system of  claim 1 , wherein the misregistration pattern is configured to enhance at least color uniformity of the color image. 
     
     
         3 . The system of  claim 2 , further comprising:
 third means for creating a third colored dot pattern on the surface of the physical medium, the third colored dot patter having a third color, the dots forming the third colored dot pattern being spaced at third predetermined distances from each other, wherein at least one of the dots forming the third colored dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern;   wherein the means for controlling is configured to control the third predetermined distances to result in a particular intentional misregistration pattern between the dots of the third colored dot pattern and the dots of both the first colored dot pattern and the second colored dot pattern.   
     
     
         4 . The system of  claim 2 ,wherein the system is a thermal imaging system and wherein the surface is a receiver substrate. 
     
     
         5 . The system of  claim 3 , wherein the system is a thermal imaging system and wherein the surface is a receiver substrate. 
     
     
         6 . The system of  claim 3 , wherein the means for controlling comprises means for controlling the third predetermined distances to be equal to the first predetermined distances and for aligning the third colored dot pattern with the first colored dot pattern. 
     
     
         7 . The system of  claim 5 , wherein the receiver substrate is formed as a web or ribbon, and wherein the system further comprises:
 means for reeling the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein the first means comprises:
 a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image, 
 a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 means for moving the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein the second means comprising:
 a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction, 
 a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 means for moving the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein the third means comprising:
 a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 means for moving the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         8 . The system of  claim 7 , wherein the first color is cyan, the second color is magenta, and the third color is yellow. 
     
     
         9 . The system of  claim 1 , wherein the system is subjected to mechanical misalignment perturbation, wherein the misregistration pattern is configured to render imperceptible optical artifacts of mechanical misalignment perturbation which otherwise would have been perceptible. 
     
     
         10 . The system of  claim 6 , wherein the receiver substrate is formed as a web or ribbon, and wherein the system further comprises:
 means for reeling the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein the first means comprises:
 a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image, 
 a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 means for moving the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein the second means comprising:
 a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction, 
 a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 means for moving the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein the third means comprising:
 a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 means for moving the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         11 . The system of  claim 10 , wherein the controlling means further comprises:
 clock means for generating a plurality of timing clock pulse trains;   pulse generator means, operatively coupled to the clock means, for providing a plurality of outputs of excitation pulse bursts in timed sequence with at least one of the clock pulse trains; and   means for operatively coupling:
 each one of the first predetermined number of thermally-controlled print head elements to a like number of a first group of the outputs respectively from the pulse generator means, the first group of the outputs being in timed sequence with a first one of the clock pulse trains, 
 each one of the second predetermined number of thermally-controlled print head elements to a like number of a second group of the outputs respectively from the pulse generator means, the second group of the outputs being in timed sequence with a second one of the clock pulse trains, and 
 each one of the third predetermined number of the thermally-controlled print head elements to a like number of a third group of the outputs respectively from the pulse generator means, the third group of the outputs being in timed sequence with the first one of the clock pulse trains; 
   wherein the time intervals between successive bursts from the first group of outputs are equal to each other and equal to the time intervals between successive the bursts from the third group of outputs.   
     
     
         12 . The system of  claim 11 , wherein the first predetermined number of thermally-controlled print head elements is 300 per inch, the second predetermined number of thermally-controlled print head elements is 400 per inch, and the third predetermined number of thermally-controlled print head elements is 300 per inch. 
     
     
         13 . The system of  claim 12 , the system further comprising:
 means for coordinating the timing of the plurality of excitation pulse burst outputs and the first speed;   means for controlling, responsive to operation of the coordinating means, each one of the thermally-controlled print head elements of the first print head and each one of the thermally-controlled print head elements of the third print head to deposit 400 dots per inch per head on the surface with each respective one of the 400 dots per inch from the third print head being deposited upon its corresponding one of the 400 dots per inch from the first print head, thereby depositing a 300 by 400 dots per inch pattern within the field of view of the image; and   means for controlling, responsive to operation of the coordinating means, each one of the thermally-controlled print head elements of the second print head to deposit 266 dots per inch on the surface throughout the field of view, thereby intermingling a 400 by 266 dots per inch pattern with the 300 by 400 dots per inch pattern;   wherein the superimposition of dots in this manner is configured to enhance color uniformity of the color image, each one of the dots being individually indistinguishable to a naked eye of a viewer.   
     
     
         14 . An apparatus for creating a color image on a physical medium having a planar surface using a plurality of dot patterns, the planar surface having first and second orthogonal spatial dimensions, the physical medium being movable in a first direction parallel to the surface, the apparatus comprising:
 first apparatus configured to create a first colored dot pattern on the surface of the physical medium, the first colored dot pattern having a first color, the dots forming the first colored dot pattern being spaced at first predetermined distances from each other;   second apparatus configured to create a second colored dot pattern on the surface of the physical medium, the first colored dot pattern having a second color, the dots forming the second colored dot pattern being spaced at second predetermined distances from each other, wherein at least one of the dots forming the second colored dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern; and   control apparatus configured to control the first predetermined distances and the second predetermined distances to result in a particular intentional misregistration pattern between the dots of the second colored dot pattern and the dots of the first colored dot pattern;   wherein the first and second dot patterns each comprise a plurality of dots being randomly spaced on the surface of the physical medium in the first dimension and being regularly spaced on the surface of the physical medium in the second dimension.   
     
     
         15 . The apparatus of  claim 14 , wherein the misregistration pattern is configured to enhance at least color uniformity of the color image. 
     
     
         16 . The apparatus of  claim 15 , further comprising:
 third apparatus configured to create a third colored dot pattern on the surface of the physical medium, the third colored dot pattern having a third color, the dots forming the third colored dot pattern being spaced at third predetermined distances from each other, wherein at least one of the dots forming the third dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern;   wherein the control apparatus comprises a device for controlling the third predetermined distances to result in another particular intentional misregistration pattern between the dots of the third colored dot pattern and the dots of both the first colored dot pattern and the second colored dot pattern.   
     
     
         17 . The apparatus of  claim 15 , wherein the apparatus is thermal imaging apparatus and wherein the surface is a receiver substrate. 
     
     
         18 . The apparatus of  claim 16 , wherein the apparatus is thermal imaging apparatus and wherein the surface is a receiver substrate. 
     
     
         19 . The apparatus of  claim 16 , wherein the control apparatus includes another device configured to control the third predetermined distances to be equal to the first predetermined distances and configured to align the third colored dot pattern with the first colored dot pattern. 
     
     
         20 . The apparatus of  claim 18 , wherein the receiver substrate is formed as a web or ribbon, and wherein the apparatus further comprises:
 a reeling apparatus configured to reel the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein the first apparatus comprises:
 a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image; 
 a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 a first drive apparatus configured to move the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein the second apparatus comprises:
 a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 a second drive apparatus configured to move the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein the third apparatus comprises:
 a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 a third drive apparatus configured to move the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         21 . The apparatus of  claim 20 , wherein the first color is cyan, the second color is magenta, and the third color is yellow. 
     
     
         22 . The apparatus of  claim 14 , wherein the apparatus is subjected to mechanical misalignment perturbation, wherein the misregistration pattern is configured to render imperceptible optical artifacts of mechanical misalignment perturbation which otherwise would have been perceptible. 
     
     
         23 . The apparatus of  claim 19 , wherein the receiver substrate is formed as a web or ribbon, and wherein the apparatus further comprises:
 a reeling apparatus configured to reel the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein the first apparatus comprises:
 a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image; 
 a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 a first drive apparatus configured to move the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein the second apparatus comprises:
 a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 a second drive apparatus configured to move the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein the third apparatus comprises:
 a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 a third drive apparatus configured to move the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         24 . The apparatus of  claim 23 , wherein the control apparatus further comprises:
 a clock configured to generate a plurality of timing clock pulse trains;   a pulse generator, operatively coupled to the clock, configured to provide a plurality of outputs of excitation pulse bursts in timed sequence with at least one of the clock pulse trains; and   an apparatus configured to operatively couple:
 each one of the first predetermined number of the thermally-controlled print head elements to a like number of a first group of the outputs respectively from the pulse generator, the first group of the outputs being in timed sequence with a first one of the clock pulse trains, 
 each one of the second predetermined number of the thermally-controlled print head elements to a like number of a second group of the outputs respectively from the pulse generator, the second group of the outputs being in timed sequence with a second one of the clock pulse trains, and 
 each one of the third predetermined number of the thermally-controlled print head elements to a like number of a third group of the outputs respectively from the pulse generator, the third group of the outputs being in timed sequence with the first one of the clock pulse trains; 
   wherein the time intervals between successive bursts from the first group of outputs are equal to each other and equal to the time intervals between successive the bursts from the third group of outputs.   
     
     
         25 . The apparatus of  claim 24 , wherein the first predetermined number of thermally-controlled print head elements is 300 per inch, the second predetermined number of thermally-controlled print head elements is 400 per inch, and the third predetermined number of thermally-controlled print head elements is 300 per inch. 
     
     
         26 . The apparatus of  claim 25  further comprising:
 a coordinating apparatus configured to coordinate the timing of the plurality of excitation pulse burst outputs and the first speed; 
 a first thermal control apparatus configured to control, responsive to operation of the coordinating apparatus, each one of the thermally-controlled print head elements of the first print head and each one of the thermally-controlled print head elements of the third print head to deposit 400 dots per inch per head on the surface with each respective one of the 400 dots per inch from the third print head being deposited upon its corresponding one of the 400 dots per inch from the first print head, thereby depositing a 300 by 400 dots per inch pattern within the field of view of the image; and 
 a second thermal control apparatus configured to control, responsive to operation of the coordinating apparatus, each one of the thermally-controlled print head elements of the second print head to deposit 266 dots per inch on the surface throughout the field of view, thereby intermingling a 400 by 266 dots per inch pattern with the 300 by 400 dots per inch pattern; 
 wherein the superimposition of dots in this manner is configured to enhance color uniformity of the color image, each one of the dots being individually indistinguishable to a naked eye of a viewer. 
 
     
     
         27 . A computer program product for creating a color image on a physical medium having a planar surface using a plurality of dot patterns, the planar surface having two orthogonal spatial dimensions, the physical medium being movable in a first direction parallel to the surface, the computer program product comprising instructions, the instructions comprising:
 instructions to create a first colored dot pattern on the surface of the physical medium, the first colored dot pattern having a first color, the dots forming the first colored dot pattern being spaced at first predetermined distances from each other;   instructions to create a second colored dot pattern on the surface of the physical medium, the second colored dot pattern having a second color, the dots forming the second colored dot pattern being spaced at second predetermined distances from each other, wherein at least one of the dots forming the second colored dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern; and   instructions to control the first predetermined distances and the second predetermined distances to result in a particular intentional misregistration pattern between the dots of the second colored dot pattern and the dots of the first colored dot pattern;   wherein the first and second dot patterns each comprise a plurality of dots being randomly spaced on the surface of the physical medium in the first dimension and being regularly spaced on the surface of the physical medium in the second dimension.   
     
     
         28 . The computer program product of  claim 27 , wherein the misregistration pattern is configured to enhance at least color uniformity of the color image. 
     
     
         29 . The computer program product of  claim 27 , the instructions further comprising:
 instructions to create a third colored dot pattern on the surface of the physical medium, the third colored dot pattern having a third color, the dots forming the third colored dot pattern being spaced at third predetermined distances from each other, wherein at least one of the dots forming the third colored dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern;   wherein the instructions to control comprise instructions to control the third predetermined distances to result in a particular intentional misregistration pattern between the dots of the third colored dot pattern and the dots of both the first colored dot pattern and the second colored dot pattern.   
     
     
         30 . The computer program product of  claim 28 , wherein the computer program product is a thermal imaging computer program product and wherein the surface is a receiver substrate. 
     
     
         31 . The computer program product of  claim 29 , wherein the computer program product is a thermal imaging computer program product and wherein the surface is a receiver substrate. 
     
     
         32 . The computer program product of  claim 29 , wherein the instructions to control further comprise instructions to control the third predetermined distances to be equal to the first predetermined distances and instructions to align the third colored dot pattern with the first colored dot pattern. 
     
     
         33 . The computer program product of  claim 31 , wherein the receiver substrate is formed as a web or ribbon, and wherein the instructions further comprise:
 instructions to reel the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein the instructions to create the first colored dot pattern comprise:
 instructions to control a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image, 
 instructions to control a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 instructions to move the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein the instructions to create the second colored dot pattern comprise:
 instructions to control a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction, 
 instructions to control a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 instructions to move the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein the instructions to create the third colored dot pattern comprise:
 instructions to control a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 instructions to control a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 instructions to move the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         34 . The computer program product of  claim 33 , wherein the first color is cyan, the second color is magenta, and the third color is yellow. 
     
     
         35 . The computer program product of  claim 27 , wherein the misregistration pattern is configured to render imperceptible optical artifacts of mechanical misalignment perturbation which otherwise would have been perceptible. 
     
     
         36 . The computer program product of  claim 32 , wherein the receiver substrate is formed as a web or ribbon, and wherein the instructions further comprise:
 instructions to reel the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein the instructions to create the first colored dot pattern comprise:
 instructions to control a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image, 
 instructions to control a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 instructions to move the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein the instructions to create the second colored dot pattern comprise:
 instructions to control a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction, 
 instructions to control a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 instructions to move the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein the instructions to create the third colored dot pattern comprise:
 instructions to control a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 instructions to control a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 instructions to move the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         37 . The computer program product of  claim 36 , wherein the instructions to control further comprise:
 instructions to generate generating a plurality of timing clock pulse trains; and   instructions to generate a plurality of outputs of excitation pulse bursts in timed sequence with at least one of the clock pulse trains;   wherein each one of the first predetermined number of thermally-controlled print head elements is operatively coupled to a like number of a first group of the outputs respectively from the pulse generator means, the first group of the outputs being in timed sequence with a first one of the clock pulse trains;   wherein each one of the second predetermined number of thermally-controlled print head elements is operatively coupled to a like number of a second group of the outputs respectively from the pulse generator means, the second group of the outputs being in timed sequence with a second one of the clock pulse trains;   wherein each one of the third predetermined number of the thermally-controlled print head elements is operatively coupled to a like number of a third group of the outputs respectively from the pulse generator means, the third group of the outputs being in timed sequence with the first one of the clock pulse trains;   wherein the time intervals between successive bursts from the first group of outputs are equal to each other and equal to the time intervals between successive the bursts from the third group of outputs.   
     
     
         38 . The computer program product of  claim 37 , wherein the first predetermined number of thermally-controlled print head elements is 300 per inch, the second predetermined number of thermally-controlled print head elements is 400 per inch, and the third predetermined number of thermally-controlled print head elements is 300 per inch. 
     
     
         39 . The computer program product of  claim 38 , the instructions further comprising:
 instructions to coordinate the timing of the plurality of excitation pulse burst outputs and the first speed;   instructions to control each one of the thermally-controlled print head elements of the first print head and each one of the thermally-controlled print head elements of the third print head to deposit 400 dots per inch per head on the surface with each respective one of the 400 dots per inch from the third print head being deposited upon its corresponding one of the 400 dots per inch from the first print head, thereby depositing a 300 by 400 dots per inch pattern within the field of view of the image; and   instructions to control each one of the thermally-controlled print head elements of the second print head to deposit 266 dots per inch on the surface throughout the field of view, thereby intermingling a 400 by 266 dots per inch pattern with the 300 by 400 dots per inch pattern;   wherein the superimposition of dots in this manner is configured to enhance color uniformity of the color image, each one of the dots being individually indistinguishable to a naked eye of a viewer.   
     
     
         40 . A method for creating a color image on a physical medium having a planar surface using a plurality of dot patterns, the planar surface having first and second orthogonal dimensions, the physical medium being movable in a first direction parallel to the surface, the method comprising:
 creating a first colored dot pattern on the surface of the physical medium, the first colored dot pattern having a first color, the dots forming the first colored dot pattern being spaced at first predetermined distances from each other;   creating a second colored dot pattern on the surface of the physical medium, the second colored dot pattern having a second color, the dots forming the second colored dot pattern being spaced at second predetermined distances from each other, wherein at least one of the dots forming the second colored dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern; and   controlling the first predetermined distances and the second predetermined distances to result in a particular intentional misregistration pattern between the dots of the second colored dot pattern and the dots of the first colored dot pattern;   wherein the first and second dot patterns each comprise a plurality of dots being randomly spaced on the surface of the physical medium in the first dimension and being regularly spaced on the surface of the physical medium in the second dimension.   
     
     
         41 . The method of  claim 40 , wherein the misregistration pattern is configured to enhance at least color uniformity of the color image. 
     
     
         42 . The method of  claim 41 , further comprising:
 creating a third colored dot pattern on the surface of the physical medium, the third colored dot patter having a third color, the dots forming the third colored dot pattern being spaced at third predetermined distances from each other, wherein at least one of the dots forming the third colored dot pattern is at least partially superimposed on at least one of the dots forming the first colored dot pattern; and   controlling the third predetermined distances to result in a particular intentional misregistration pattern between the dots of the third colored dot pattern and the dots of both the first colored dot pattern and the second colored dot pattern.   
     
     
         43 . The method of  claim 41 , wherein the method is a thermal imaging method and wherein the surface is a receiver substrate. 
     
     
         44 . The method of  claim 42 , wherein the method is a thermal imaging method and wherein the surface is a receiver substrate. 
     
     
         45 . The method of  claim 42 , further comprising controlling the third predetermined distances to be equal to the first predetermined distances and for aligning the third colored dot pattern with the first colored dot pattern. 
     
     
         46 . The method of  claim 44 , wherein the receiver substrate is formed as a web or ribbon, and wherein the method further comprises:
 reeling the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein creating the first colored dot pattern comprises:
 controlling a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image, 
 controlling a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 moving the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein creating the second colored dot pattern comprises:
 controlling a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction, 
 controlling a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 moving the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein creating the third colored dot pattern comprises:
 controlling a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 controlling a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 moving the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         47 . The method of  claim 46 , wherein the first color is cyan, the second color is magenta, and the third color is yellow. 
     
     
         48 . The method of  claim 40 , wherein the misregistration pattern is configured to render imperceptible optical artifacts of mechanical misalignment perturbation which otherwise would have been perceptible. 
     
     
         49 . The method of  claim 45 , wherein the receiver substrate is formed as a web or ribbon, and wherein the method further comprises:
 reeling the receiver substrate in the first direction at a first speed to obtain a moving receiver substrate;   wherein creating the first colored dot pattern comprises:
 controlling a first thermal print head fixedly mounted relative to the moving receiver substrate, the first thermal print head including a first predetermined number of thermally-controlled print head elements linearly and regularly displaced over a fixed distance in a direction parallel to the surface and perpendicular to the first direction, the fixed distance defining one dimension of a field of view of the image, 
 controlling a first donor ribbon having an ink side of the first color, the first donor ribbon positioned between the first thermal print head and the receiver substrate, the ink side of the first color touching the receiver substrate, and 
 moving the first donor ribbon in the first direction at the first speed while in contact with the receiver substrate; 
   wherein creating the second colored dot pattern comprises:
 controlling a second thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the first thermal print head in the first direction, the second thermal print head including a second predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction, 
 controlling a second donor ribbon having an ink side of the second color, the second donor ribbon positioned between the second thermal print head and the receiver substrate, the ink side of the second color touching the receiver substrate, and 
 moving the second donor ribbon in the first direction at the first speed while in contact with the receiver substrate; and 
   wherein creating the third colored dot pattern comprises:
 controlling a third thermal print head fixedly mounted relative to the moving receiver substrate and displaced from the second thermal print head in the first direction, the third thermal print head including a third predetermined number of thermally-controlled print head elements linearly and regularly displaced over the fixed distance within the field of view in a direction parallel to the surface and perpendicular to the first direction; 
 controlling a third donor ribbon having an ink side of the third color, the third donor ribbon positioned between the third thermal print head and the receiver substrate, the ink side of the third color touching the receiver substrate, and 
 moving the third donor ribbon in the first direction at the first speed while in contact with the receiver substrate. 
   
     
     
         50 . The method of  claim 49 , wherein the controlling further comprises:
 generating a plurality of timing clock pulse trains from a pulse generator;   generating a plurality of outputs of excitation pulse bursts in timed sequence with at least one of the clock pulse trains;   operatively coupling each one of the first predetermined number of thermally-controlled print head elements to a like number of a first group of the outputs respectively from the pulse generator means, the first group of the outputs being in timed sequence with a first one of the clock pulse trains;   operatively coupling each one of the second predetermined number of thermally-controlled print head elements to a like number of a second group of the outputs respectively from the pulse generator means, the second group of the outputs being in timed sequence with a second one of the clock pulse trains; and   operatively coupling each one of the third predetermined number of the thermally-controlled print head elements to a like number of a third group of the outputs respectively from the pulse generator means, the third group of the outputs being in timed sequence with the first one of the clock pulse trains;   wherein the time intervals between successive bursts from the first group of outputs are equal to each other and equal to the time intervals between successive the bursts from the third group of outputs.   
     
     
         51 . The method of  claim 40 , wherein the first predetermined number of thermally-controlled print head elements is 300 per inch, the second predetermined number of thermally-controlled print head elements is 400 per inch, and the third predetermined number of thermally-controlled print head elements is 300 per inch. 
     
     
         52 . The method of  claim 51 , further comprising:
 coordinating the timing of the plurality of excitation pulse burst outputs and the first speed;   means for controlling each one of the thermally-controlled print head elements of the first print head and each one of the thermally-controlled print head elements of the third print head to deposit 400 dots per inch per head on the surface with each respective one of the 400 dots per inch from the third print head being deposited upon its corresponding one of the 400 dots per inch from the first print head, thereby depositing a 300 by 400 dots per inch pattern within the field of view of the image; and   means for controlling each one of the thermally-controlled print head elements of the second print head to deposit 266 dots per inch on the surface throughout the field of view, thereby intermingling a 400 by 266 dots per inch pattern with the 300 by 400 dots per inch pattern;   wherein the superimposition of dots in this manner is configured to enhance color uniformity of the color image, each one of the dots being individually indistinguishable to a naked eye of a viewer.