Image recording apparatus and method

An image recording apparatus, comprising:

• a full-line recording head in which a plurality of image-recording elements are arrayed across a length corresponding to an entire width of a printing medium;
• a conveyance device which conveys at least one of the recoding head and the printing medium in a direction substantially orthogonal to a width direction of the printing medium so as to move the recording head and the printing medium relatively to each other in a relative conveyance direction;
• and
• a recording control device which performs recording control so that when recording is carried out with respect to a solid area of a recorded image with a substantially uniform density, diameter of dots in the solid area recorded on the printing medium with the image-recording elements is made greater than an array pitch of the image-recording elements projected so as to be aligned in a main scanning direction substantially orthogonal to the relative conveyance direction, wherein the diameter of the dots, arrangement of the dots, and the array pitch of the image-recording elements are set so as to satisfy the following formula:
• {Ei+×(Ei+−Si+)}1/2<α×(Np/2)×Ds,
• where:
• Np is the array pitch of the image-recording elements in the main scanning direction,
• Ds is a predetermined distance in a sub-scanning direction that is orthogonal to the main scanning direction on the printing medium,
• Ei+ is a total surface area of a portion contained in a rectangular area of (Np/2)×Ds on a side of an (i+1)-th image-recording element, of a surface area covered with dots formed by an i-th image-recording element under ideal conditions,
• Si+ is a total surface area of a portion contained in the rectangular area of (Np/2)×Ds on the side of the (i+1)-th image-recording element, of a surface area covered with dots formed by an image-recording element other than the i-th element under ideal conditions, and
• α is a predetermined constant.