Abstract: An ink cartridge for a thermal ink jet printer containing a separate collapsible ink reservoir which is kept under negative pressure by a pressure regulator to prevent ink leakage. The collapsible reservoir has one or more flexible sidewalls connected at their periphery to form an ink reservoir, wherein said sidewalls include a plurality of layers. The pressure regulator comprises a pair of spaced parallel side plates urged apart by a spring toward the adjacent reservoir sidewalls whereby the reservoir is collapsible against the spring pressure to an essentially flat shape to permit substantially complete dispensation of ink from the reservoir.

Abstract: In one of the preferred embodiments, an inkjet printhead includes a nozzle member formed of a polymer material that has been laser-ablated to form inkjet orifices. The nozzle member also has formed on it conductive traces for supplying electrical signals to heating elements on a substrate mounted to a surface of the nozzle member. In a preferred method, the orifices are formed by Excimer laser ablation.

Abstract: An ink jet pen supply cartridge having a spring biased ink reservoir with a visual indication of remaining ink quantity. The reservoir tends to collapse laterally as the ink supply decreases due to differential pressure exerted thereto. The spring-reservoir is contained in a rigid cartridge and a pair of flexible tape members are cemented or welded, one to each side of the spring-reservoir, and extend generally parallel toward a narrow end surface of the cartridge at which they overlap and can be viewed through a window. The overlapping relationship of the tape members provide ink quantity indicia which change as the spring-reservoir collapse draws them past each other.

Abstract: A method for operating a thermal ink jet printer including a printhead having ink firing heater resistors responsive to pulses provided to the printhead. Warming voltage pulses are applied to the printhead to warm the printhead to a temperature that is at least as high as a temperature that would be produced pursuant to ink firing pulses of a predetermined voltage, a predetermined pulse width, and a predetermined pulse frequency. A continuous series of ink firing pulses are then applied to the printhead, starting with a pulse energy substantially equal to the predetermined reference pulse energy and a pulse frequency equal to the predetermined pulse frequency, and then incrementally decreasing the pulse energy of the ink firing pulses. The temperature of the printhead is repeatedly sampled while the ink firing pulses are applied to the ink firing resistors to produce a set of temperature samples respectively associated with the decreasing pulse energies.

Abstract: A method for operating a thermal ink jet printer including a printhead having ink firing heater resistors responsive to pulses provided to the printhead. A sequence of pulse bursts of respective increasing or decreasing pulse energies that span a predetermined pulse energy range is applied to the printhead, each pulse burst comprised of a plurality of pulses having a pulse energy that is associated with such pulse burst and is constant for all pulses in such burst, and each burst having a sufficient number of pulses to allow the printhead to achieve a steady state operating temperature at the pulse energy of the pulse burst. A steady state operating temperature sample is determined for each of the sequence of pulses bursts of different pulse energies to produce a set of temperature samples respectively associated with the increasing pulse energies, and a turn on pulse energy is determined from the temperature samples.