Gray scale pattern and recording method and recording apparatus employing the gray scale pattern

A gray scale pattern for use in multilevel recording performed by a recording apparatus including a recording head having an array of a plurality of recording elements for performing recording on a recording medium, said pattern being stored in a memory of said recording apparatus, and gray scale control means for performing multilevel recording by controlling a number of dots to be recorded in a pixel formed of a plurality of recording dots formed by said recording elements of said recording head, said gray scale pattern comprising:

• a plurality of blocks asymmetrically dispersed in the gray scale pattern, each of the said plurality of blocks having a plurality of discrete locations for forming dots and an area of said pixel, and in which dots to be recorded by a recording apparatus in said pixel increases starting from substantially a center location of a respective pixel in accordance with an increase in a gray scale pattern.

A recording method for use in gray scale recording by a recording apparatus including a recording head having an array of a plurality of recording elements for performing recording on a recording medium, and gray scale control means for performing multilevel recording by controlling a number of dots to be recorded in a single pixel formed of a plurality of recording dots formed by said recording elements of said recording head, said method comprising the steps of:

• providing a gray scale pattern including a plurality of blocks each having a plurality of discrete locations for forming dots and an area smaller than an area of said single pixel, and in which dots to be recorded in each of said plurality of blocks are recorded starting from almost a center thereof;
• and
• recording such that as the number of dots recorded in said single pixel increases, the number of dots to be recorded in said plurality of blocks increases by a predetermined amount in a predetermined order such that consecutive dots are not recorded in the same block of said plurality of blocks.

A recording method comprising the steps of:

• providing a recording head having a plurality of recording elements for recording a pixel with a plurality of dots according to a gray scale pattern, the pattern including a plurality of blocks subdividing the pixel, each block having a plurality of physically separate locations for forming dots and an area smaller than an area of the pixel;
• and
• driving the recording elements such that a number of times of driving a recording element that is driven most often in a range defined by the gray scale pattern to record the pixel is not more than twice a number of times of driving another recording element that is driven least often in the range defined by said gray scale pattern to record the pixel.

A dither matrix pattern for use in gray scale recording of an image performed by a recording apparatus using a recording head having an array of a plurality of recording elements for performing recording on a recording medium, the recording apparatus controlling the recording elements to perform recording, comprising:

• a first block and a second block, each of the first block and the second block consisting of a plurality of concentration pattern blocks dispersed to correspond to an arraying direction in which the recording elements of the recording head are arrayed, each concentration pattern block having a dot concentration pattern in which a threshold increases starting from the center to the outer edge of the block,
• wherein the arrangement of the concentration pattern blocks differs between the first block and the second block.

A recording apparatus for use with a recording head having an array of a plurality of recording elements for performing recording on a recording medium, comprising:

• gray scale recording control means for performing gray scale recording using the recording head by controlling, according to a dither matrix pattern, the recording elements of the recording head to record dots in an area of the recording medium on the basis of a comparison of a gray scale level indicated by data for use in recording with a threshold in the dither matrix pattern,
• wherein the dither matrix pattern includes a first block and a second block, each of the first block and the second block consisting of a plurality of concentration pattern blocks dispersed to correspond to an arraying direction in which the recording elements of the recording head are arrayed, each concentration pattern block having a dot concentration pattern in which a threshold increases starting from the center to the outer edge of the block, and
• wherein the arrangement of the concentration pattern blocks differs between the first block and the second block of the dither matrix pattern.