Apparatus and method for controlling a thermal printer apparatus

• US 4,621,271 A
• Filed: 09/23/1985
• Issued: 11/04/1986
• Est. Priority Date: 09/23/1985
• Status: Expired due to Term

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Brownstein, Scott A.
• Primary Examiner(s): Evans, A.
• Application Number:
  US06/778,960
• Time in Patent Office: 407 Days
• Field of Search: 346/76 PH, 400/120, 219/216 PH
• US Class Current: 347/211
• CPC Class Codes: B41M 5/38221 Apparatus features
• CPC Class Codes: H04N 1/40031 for a plurality of reproducing elements simultaneously

Abstract

A thermal printer apparatus is disclosed which includes a print head having a plurality of groups of thermal pixels. The thermal pixels in each group are simultaneously addressed in parallel. Each group is addressed a plurality of times. The apparatus selectively energizes the thermal pixels of each group when they are addressed until each thermal pixel is at a temperature where it can supply energy to a carrier member which delivered an amount of dye to a receiver which corresponds to a desired dye density in an image pixel.

Claims

1. In a thermal printer apparatus including a print head having a number of thermal pixels, one for each image pixel, formed into a plurality of groups of thermal pixels, the thermal pixels of each group being simultaneously addressable in parallel and having N different possible temperature levels, the improvement comprising:

a. a storage device having a plurality of stages, one for each thermal pixel;

b. means for sequentially storing N digital signals in the stages of the storage device, in which the state of each stage corresponds to whether or not a corresponding thermal pixel is to be energized;

c. means for sequentially addressing the groups of thermal pixels each time a digital signal is stored in the storage device with each group of thermal pixels being addressed N times; and

d. means for selectively energizing each thermal pixel each time it is addressed depending upon the state of its corresponding stage until each thermal pixel is at one of N possible temperatures.

2. Thermal printing system for forming a continuous tone color image composed of dye image pixels, each image pixel having N different possible dye density levels, comprising:

a. a thermal print head for printing a line of dye image pixels at a time and including a plurality of groups of thermal pixels, the thermal pixels of each group being simultaneously addressable in parallel, each thermal pixel corresponding to an image pixel in a line, and each thermal pixel being adapted when addressed to be selectively energized;

b. a carrier including at least one heat transferable dye and being positionable in relation to the thermal pixels such that the amount of dye sublimed for each image pixel is proportional to the energy provided by an energized thermal pixel;

c. a receiver disposed in relation to the carrier sheet and the print head for receiving sublimed dye to form dye image pixels;

d. a storage device having a plurality of states, one for each thermal pixel;

e. means for sequentially storing N digital signals in the stages of said shift register in which the state of each stage corresponds to whether or not a corresponding thermal pixel is to be energized;

f. means for sequentially addressing the groups of thermal pixels, one for each time a digital signal is stored in said shift register such that each group of thermal pixels is addressed N times; and

g. means for selectively energizing each thermal pixel each time it is addressed depending upon the state of its corresponding storage device stage until each thermal pixel is at one of N possible temperatures and which causes dye to transfer from the carrier and be received by the receiver at a desired dye density level.

3. A method of forming a continuous tone color image composed of dye image pixels, each image pixel having N different possible dye density levels, comprising the steps of:

a. positioning a carrier having transferable dye and a receiver for receiving transferred dye relative to a print head which includes a plurality of groups of thermal pixels, with the thermal pixels of each group being simultaneously addressable in parallel;

b. sequentially addressing the groups of thermal pixels such that each group of thermal pixels is addressed N times; and

c. selectively energizing the thermal pixels each time they are addressed until each thermal pixel is able to deliver energy which corresponds to a particular one of the N dye densities.

4. A method of forming a continuous tone color image composed of dye image pixels, each image pixel having N different possible dye density levels, comprising the steps of:

a. moving a carrier having transferable dye and moving receiver for receiving transferred dye relative to a print head which includes a plurality of groups of thermal pixels, with the thermal pixels of each group being simultaneously addressable in parallel as the carrier and receiver are being moved;

b. sequentially addressing the groups of thermal pixels such that each group of thermal pixels is addressed N times; and

c. selectively energizing the thermal pixels each time they are addressed until each thermal pixel is able to deliver energy which corresponds to a particular one of the N dye densities.

5. A method of forming a continuous tone color image composed of dye image pixels, each pixel having N different dye density levels, comprising the steps of:

a. positioning a carrier sheet having transferable dye and a receiver for receiving transferred dye relative to a print head which includes a plurality of groups of thermal pixels, with the thermal pixels of each group being simultaneously addressable in parallel;

b. sequentially storing N digital signals in the stages of a storage device in which the state of each stage corresponds to whether or not a corresponding thermal pixel is to be energized;

c. sequentially addressing the groups of thermal pixels each time a digital signal is stored in the storage device such that each group of thermal pixels is addressed N times; and

d. selectively energizing each thermal pixel each time it is addressed depending upon the state of its corresponding stage until each thermal pixel is at one of N possible temperatures which corresponds to a desired dye density, such that a color image with the desired dye density image pixels is formed in the receiver.

6. A method of forming a continuous tone dye image composed of a predetermined number of image pixels, each pixel having N different dye density levels, comprising the steps of:

a. positioning a carrier sheet having transferable dye and a receiver for receiving transferred dye relative to a print head having the predetermined number of thermal pixels, one for each image pixel, formed into plurality of groups of thermal pixels, with the thermal pixels of each group being simultaneously addressable in parallel;

b. sequentially storing N digital signals in stages of a shift register in which the state of each stage corresponds to whether or not a corresponding thermal pixel is to be energized;

c. sequentially addressing the groups of thermal pixels each time a digital signal is stored in the storage device such that each group of thermal pixels is addressed N times; and

d. selectively energizing each thermal pixel each time it is addressed depending upon the state of its corresponding shift register stage until each thermal pixel is at one of N possible temperatures which corresponds to a desired dye density, such that a color image with the desired dye density image pixels is formed in the receiver.

7. Thermal printing apparatus for forming a continuous tone dye image composed of dye image pixels, each image pixel having N different possible dye density levels, comprising:

a. a thermal print head for printing a line of image pixels and including a plurality of groups of thermal pixels, the thermal pixels of each group being simultaneously addressable in parallel, each thermal pixel corresponding to an image pixel in a line, and each thermal pixel being adapted when addressed to be selectively energized;

b. a member including at least one heat transferable dye and being positionable in relation to the thermal pixels such that the amount of dye transferred for each image pixel is proportional to the energy provided by an energized thermal pixel; and

c. means for controlling image dye density including (i) means for serially addressing each pixel group N times and (ii) means for selectively energizing each thermal pixel of a group when addressed until each thermal pixel is able to deliver energy to the member to cause dye to transfer such that the desired image pixel dye densities in a line of image pixels are formed.