Abstract: An apparatus for detecting faulty nozzles in an ink jet printer includes an ink jet print head having a plurality of ink jet nozzles disposed adjacent a print medium. The print head prints a reference image on the print medium formed by ink droplets ejected from many of the nozzles. The print head also prints individual test images corresponding to each nozzle by ejecting ink droplets from each of the nozzles separately and sequentially. A print head scan mechanism scans the print head in a first direction relative to the print medium as the test images are printed. A print medium advance mechanism moves the print medium in a second direction between the printing of the reference image and the printing of the test images, where the second direction is orthogonal to the first direction. In this manner, the apparatus leaves nonprinted areas on the print medium between the reference image and the individual test images.

Abstract: An apparatus provides identification information related to at least one ink jet print head in an ink jet printer. The apparatus includes a printer controller for providing a first identification data string comprising n number of bits, at least one of which has a first state, and no more than n−1 number of which have a second state different from the first state. Coupled to the printer controller is a first ink jet print head having a first serial input shift register. The first serial input shift register has at least n number of bit positions for receiving the n number of bits of the first identification data string. The first ink jet print head also includes at least n number of first latches, each of which is coupled to a corresponding one of the n number of bit positions of the first shift register. The n number of first latches are for latching the n number of bits of the first identification data string from the n number of bit positions of the first shift register.

Abstract: An ink jet print head is controllable based at least in part on q number of first control signals and p number of second control signals. The print head includes a print head integrated circuit chip having ink-heating resistors for generating heat when activated. The print head chip also has a switching circuit for receiving the first and second control signals, and for selectively activating the resistors by allowing electrical current to flow through selected resistors based at least in part on the first and second control signals. The switching circuit is operable in either a first operating mode or a second operating mode, where q is equivalent to q1 in the first operating mode, and is equivalent to q2 in the second operating mode, and where q1 is twice q2. In the first operating mode, p is equivalent to p1, and in the second operating mode, p is equivalent to p2, where p2 is twice p1. The product of q1 multiplied by p1 is equivalent to the product of q2 multiplied by p2.

Abstract: A flexible circuit on an ink jet print head cartridge provides electrical connection between a control circuit in an ink jet printer and electrical contacts on a print head integrated circuit. During operation of printer, the contacts and the flexible circuit are exposed to a corrosive ink contained in the cartridge. The flexible circuit includes a first conductor for electrically connecting to a contact on the print head integrated circuit. The first conductor carries a first voltage when the flexible circuit is connected to the control circuit. A second conductor is disposed adjacent the first conductor for electrically connecting to another contact on the print head integrated circuit. When the flexible circuit is connected to the control circuit the second conductor carries a second voltage which is different from the first voltage. Thus, a voltage difference exists between the first conductor and the second conductor.

Abstract: An ink jet print head includes a nozzle plate having a substantially linear array of ink jet nozzles through which ink droplets are ejected toward a print medium. An integrated circuit chip, which is disposed adjacent the nozzle plate on the print head, includes a semiconductor substrate, a source voltage conductor connected to a source voltage, and a ground return conductor. A substantially linear array of ink heating resistors are disposed on the substrate substantially parallel to the length of the chip, each associated with a corresponding one of the ink jet nozzles. The chip also includes a plurality of substrate heater resistors disposed on the substrate in a substantially linear arrangement and aligned substantially parallel with the nozzles. The substrate heater resistors are electrically connected in parallel, with one node of each being connected to the source voltage conductor and another node of each being connected to the ground return conductor.

Abstract: An ink jet printer receives image data defining a pattern of dots in a non-square rectangular grid and prints the pattern of dots on a print medium based on the image data. The pattern of dots consists of at least four interlaced checkerboard arrays of dots printed in four passes of the print head across the print medium, where each one of the four checkerboard arrays is printed during a different one of the four passes. Each of the checkerboard arrays is offset from the other checkerboard arrays by a predetermined spacing in at least one of the first and second directions. The printer prints the second checkerboard array horizontally offset from the first checkerboard array by a distance substantially equivalent to {fraction (5d/4)}, where d is the diameter of the printed dots.