Printhead and printing apparatus using printhead

• US 6,371,588 B1
• Filed: 12/17/1999
• Issued: 04/16/2002
• Est. Priority Date: 12/21/1998
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Tsuruoka, Yuji
• Primary Examiner(s): Le, N.
• Assistant Examiner(s): HSIEH, SHIH WEN
• Application Number:
  US09/466,179
• Time in Patent Office: 851 Days
• Field of Search: 347/12, 347/13, 347/180, 347/181, 347/182, 347/19, 347/43, 347/40
• US Class Current: 347/12
• CPC Class Codes: B41J 2/04505 aiming at correcting alignment
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/04543 Block driving
• CPC Class Codes: B41J 2/04573 Timing; Delays
• CPC Class Codes: B41J 2/0458 controlling heads based on heating elements forming bubbles

Abstract

A printhead which high-precisely performs registration adjustment between print dots even in use of plural printheads or a printhead having plural printing element arrays, and a printing apparatus using the printhead. Registration adjustment can be performed with a value equal to or less than a printing resolution in a main-scanning direction by changing the order of nozzle blocks of at least one of two nozzle arrays, in accordance with a stored amount of registration shift, without transmission of a specific control signal from the printing apparatus.

Claims

1. A printhead capable of printing by dividing a plurality of printing elements constituting a printing element array into a plurality of blocks and time-divisionally driving said plurality of printing elements in block units, comprising:

a memory circuit for storing a value based on an amount of registration shift equal to or less than a printing resolution in a direction in which the printing element array is scanned relative to a printing medium; and

a changing circuit that changes an order of blocks to be driven in accordance with the value stored in said memory circuit.

2. The printhead according to claim 1, wherein a number of the printing element array is plural,

said plurality of printing element arrays are arranged at an interval along the direction, and

said changing circuit changes the order of blocks to be driven in at least one of said plurality of printing element arrays.

3. The printhead according to claim 2, wherein

said plurality of printing element array includes a first and second printing element arrays.

4. The printhead according to claim 3, wherein division of said plurality of printing elements into blocks is made by dividing said plurality of printing elements of said first and second printing element arrays into blocks by N printing elements sequentially.

5. The printhead according to claim 3, wherein division of said plurality of printing elements into blocks is made by dividing said plurality of printing elements of said first and second printing element arrays into blocks by K printing elements each selected from every M printing elements.

6. The printhead according to claim 3, wherein the direction of said plurality of printing elements of said first and second printing element arrays is diagonal to the direction.

7. The printhead according to claim 3, further comprising third and fourth printing element arrays in said first direction in parallel to said first and second printing element arrays,

wherein color printing is performed by discharging yellow ink, magenta ink, cyan ink and black ink from said first, second, third and fourth printing element arrays.

8. The printhead according to claim 1, wherein said plurality of printing elements are divided into four, eight, sixteen or thirty two blocks.

9. The printhead according to claim 1, further comprising a delay circuit that delays print data output to printing elements of each block of said printing element array in accordance with change of the order of blocks to be driven by said changing circuit.

10. The printhead according to claim 1, wherein said printhead is an ink-jet printhead that performs printing by discharging ink.

11. The printhead according to claim 10, wherein said ink-jet printhead has electrothermal transducers for generating thermal energy to be supplied to ink, for discharging the ink by utilizing the thermal energy.

12. The printhead according to any one of claims 3 to 10 wherein said first and second printing element arrays are respectively assembled in separate printheads.

13. A printing apparatus which performs printing by using the printhead according to any one of claims 1 to 7, comprising:

scanning means, carrying said printhead, for reciprocate-scanning said printhead along the direction; and

output means for outputting print data to said printhead.

14. A printing apparatus which performs printing by dividing a plurality of printing elements constituting a printing element array into a plurality of blocks and time-divisionally driving said plurality of printing elements in block units, comprising:

a memory circuit for storing a value based on an amount of registration shift equal to or less than a printing resolution in a direction in which said printing element array is scanned relative to a printing medium; and

a changing circuit that changes an order of blocks to be driven in accordance with the value stored in said memory circuit.

15. The printing apparatus according to claim 14, further comprising a delay circuit that delays print data output to printing elements of each block of said printing element array in accordance with change of the order of blocks to be driven by said changing circuit.