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US4724446A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermal transfer printing apparatus

Assignee: Toshiba Corp
•
Filing: 1986-01-24
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Granted: 1988-02-09
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Expires: 2006-01-24
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Abstract

Abstract A thermal transfer printing apparatus has a thermal head comprised of a plurality of heating members aligned in line, each of the heating members transferring an ink to printing paper upon heating so as to form one dot, the thermal head moving relative to the printing paper and defining a pixel using m×n printing dots (m, n: positive integers). This apparatus further has multilevel dot pattern generating means for storing several binary dot patterns having predetermined dots of the m×n dot matrix, and for selecting, upon reception of an image signal indicating the density of each pixel, a binary dot pattern in accordance with the density of each pixel, determining multilevel data for each dot constituting the selected pattern in accordance with the density of each pixel, and generating the multilevel dot pattern in which the data for each dot is determined, and driving means, connected between the multilevel dot pattern generating means and the thermal head, for heating, in correspondence with a multilevel dot pattern, the heating member corresponding to the dot therein so as to transfer an ink onto the printing paper to form a dot pattern formed by dots having a size corresponding to the density of each pixel.

Inventors

  • 👤 Shuzo Hirahara
  • 👤 Hitoshi Nagato
  • 👤 Kazuhiko Higuchi
  • 👤 Kiyoshi Yamada
  • 👤 Tadayoshi Ohno
  • 👤 Tsutomu Kanai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 12:33
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/40087

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 212 words
A thermal transfer printing apparatus comprising: a thermal head comprised of a plurality of heating members aligned in line, each of said heating members transferring an ink to printing paper upon being heated so as to form one dot, said thermal head moving relative to the printing paper and defining a pixel using m×n printing dots (m, n: positive integers); multilevel dot pattern generating means for storing several binary dot patterns having predetermined dots of the m×n dot matrix, and for selecting, upon reception of an image signal indicating the density of each pixel, a binary dot pattern in accordance with the density of each pixel upon reception of an image signal indicating the density of each pixel, determining multilevel data for each dot constituting the selected pattern in accordance with the density of each pixel, and generating the multilevel dot pattern in which the data for each dot is determined; and driving means, connected between said multilevel dot pattern generating means and said thermal head, for heating, in correspondence with a multilevel dot pattern, the heating member corresponding to he dot therein so as to transfer an ink onto the printing paper to form a dot pattern of one block having an area that accords with the density of each pixel.
Claim 2
Dependent Claim 212 words
A thermal transfer printing apparatus comprising: a thermal head comprised of a plurality of heating members aligned in line, each of said heating members transferring an ink to printing paper upon being heated so as to form one dot, said thermal head moving relative to the printing paper and defining a pixel using m×n printing dots (m, n: positive integers); multilevel dot pattern generating means for storing several binary dot patterns having predetermined dots of the m×n dot matrix, and for selecting, upon reception of an image signal indicating the density of each pixel, a binary dot pattern in accordance with the density of each pixel upon reception of an image signal indicating the density of each pixel, determining multilevel data for each dot constituting the selected pattern in accordance with the density of each pixel, and generating the multilevel dot pattern in which the data for each dot is determined; and driving means, connected between said multilevel dot pattern generating means and said thermal head, for heating, in correspondence with a multilevel dot pattern, the heating member corresponding to he dot therein so as to transfer an ink onto the printing paper to form a dot pattern of one block having an area that accords with the density of each pixel.
Claim 3
Dependent Claim 43 words
A thermal transfer printing apparatus according to claim 1, in which said multilevel dot pattern generating means divides a density range within which each pixel can be printed into a plurality of density ranges, and stores a dot pattern in each density range.
Claim 4
Dependent Claim 75 words
A thermal transfer printing apparatus according to claim 2, in which the density ranges of the dot patterns stored in said multilevel dot pattern generating means partially overlap each other, and a density level at which the dot patterns are switched is altered in accordance with a case wherein a density is changed from a high to a low level and a case wherein a density is changed from a low to a high level.
Claim 5
Dependent Claim 63 words
A thermal transfer printing apparatus according to claim 3, in which, in the overlapping density regions of the dot patterns, a dot pattern for high density printing is selected when the density is changed from a high to a low level, and a dot pattern for low density printing is selected when the density is changed from a low to a high level.
Claim 6
Dependent Claim 67 words
A thermal transfer printing apparatus according to claim 2, wherein said multilevel dot pattern generating means stores, as a dot pattern in a low density range, a discrete dot pattern consisting of a single dot; as a dot pattern in a middle density range, a stripe dot pattern consisting of a dot array; and, as a dot pattern in a high density range, an L-shaped dot pattern.
Claim 7
Dependent Claim 39 words
A thermal transfer printing apparatus according to claim 2, in which said multilevel dot pattern generating means stores, as a multilevel dot pattern, an L-shaped dot pattern or a dot pattern consisting of a combination of L-shaped dot patterns.
Claim 8
Dependent Claim 46 words
A thermal transfer printing apparatus according to claim 2, in which said multilevel dot pattern generating means stores, as a multilevel dot pattern, dot patterns of the respective density ranges which do not form adjacent dots if the dot patterns are formed adjacent to each other.
Claim 9
Dependent Claim 35 words
A thermal transfer printing apparatus according to claim 2, in which said multilevel dot pattern generating means stores a dot pattern in which dot arrays constituting the multilevel dot pattern are aligned at corresponding positions.
Claim 10
Dependent Claim 28 words
A thermal transfer printing apparatus according to claim 2, in which said multilevel dot pattern generating means stores a rotation symmetrical dot pattern as a multilevel dot pattern.
Claim 11
Dependent Claim 38 words
A thermal transfer printing apparatus according to claim 2, in which said multilevel dot pattern generating means stores, as a multilevel dot pattern, a dot pattern in which the heating center corresponds to the center of the pattern.
Claim 12
Dependent Claim 272 words
A thermal transfer printing apparatus comprising: a thermal head comprised of a plurality of heating members aligned in line, each of said heating members transferring an ink to printing paper upon being heated so as to form one dot, said thermal head moving relative to the printing paper and defining a pixel using m×n dot matrix (m, n: positive integers); means for storing a multilevel dot pattern, the dot pattern for each density level of the pixel representing a position of a dot to be printed in the m×n dot matrix and heating energy of a heating member corresponding to the printed dot, the dot pattern in a low density range of the pixel being comprised of a single dot, the dot pattern in a middle density range including said single dot and being comprised of a dot array arranged in the direction of the relative movement of said thermal head and printing paper, and the dot pattern in a high density range being comprised of said dot array and a dot array perpendicular thereto; multilevel dot pattern generating means for selecting, upon reception of an image signal indicating the density of each pixel, a multilevel dot pattern in accordance with the density of each pixel upon reception of an image signal indicating the density of each pixel; and driving means, connected between said multilevel dot pattern generating means and said thermal head, for heating a heating member with a heating energy, the heating member and the heating energy being in accordance with the selected multilevel dot pattern so as to transfer an ink onto the printing paper to print each pixel.
Claim 13
Dependent Claim 272 words
A thermal transfer printing apparatus comprising: a thermal head comprised of a plurality of heating members aligned in line, each of said heating members transferring an ink to printing paper upon being heated so as to form one dot, said thermal head moving relative to the printing paper and defining a pixel using m×n dot matrix (m, n: positive integers); means for storing a multilevel dot pattern, the dot pattern for each density level of the pixel representing a position of a dot to be printed in the m×n dot matrix and heating energy of a heating member corresponding to the printed dot, the dot pattern in a low density range of the pixel being comprised of a single dot, the dot pattern in a middle density range including said single dot and being comprised of a dot array arranged in the direction of the relative movement of said thermal head and printing paper, and the dot pattern in a high density range being comprised of said dot array and a dot array perpendicular thereto; multilevel dot pattern generating means for selecting, upon reception of an image signal indicating the density of each pixel, a multilevel dot pattern in accordance with the density of each pixel upon reception of an image signal indicating the density of each pixel; and driving means, connected between said multilevel dot pattern generating means and said thermal head, for heating a heating member with a heating energy, the heating member and the heating energy being in accordance with the selected multilevel dot pattern so as to transfer an ink onto the printing paper to print each pixel.
Claim 14
Dependent Claim 75 words
The apparatus according to claim 11, in which, when the density of the pixel changes from a low level to a high level, the position of the dot included in the dot pattern is changed at a first threshold density level and when the density changed from a high level to a low level, the position of the dot is changed at a second threshold density level which is lower than the first threshold level.
Claim 15
Dependent Claim 29 words
The apparatus according to claim 11, in which said single dot forming the dot pattern in the low density range is a dot in the corner of the matrix.
Claim 16
Dependent Claim 28 words
The apparatus according to claim 13, in which said dots forming the dot pattern in the high density range are dots in the peripheral of the dot matrix.

References Cited (Backward Citations)

US3922484A Cited
US4394693A Cited
US4368491A Cited
US4412225A Cited
US4532523A Cited
US4536771A Cited
US4578713A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-02-08 1991-08-10 1992-02-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-02-08 1995-08-10 1996-02-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-02-08 1999-08-10 2000-02-09 $7700.00 Window Closed / Lapsed

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