Method and apparatus for maintaining colour sequence when printing

An elongate print head with a longitudinal axis, comprising at least a first array of marking elements and a second array of marking elements for printing different colours, each array of marking elements comprising a set of equally spaced marking elements, a first active marking element of the first array of marking elements being spaced apart in the direction of the longitudinal axis from a first active marking element of the second array of marking elements over a distance of at least n/I of a length of an array of marking elements, n being an integer larger than 1, I being a number of interlacing steps used in printing an image.

A method of controlling a print head, the print head comprising at least a first array of marking elements and a second array of marking elements for printing different colours, each array of marking elements comprising a set of equally spaced marking elements, the method comprising the step of:

• inhibiting the operation of second array marking elements not to be used, so that the first active marking element of the second array is spaced apart from the first active marking element of the first array.

A control unit for controlling a print head, the print head comprising at least a first array of marking elements and a second array of marking elements for printing different colours, each array of marking elements comprising a set of equally spaced marking elements, the control unit comprising means for inhibiting the operation of second array marking elements not to be used, so that the first active marking element of the second array is spaced apart from the first active marking element of the first array.