Abstract: In an embodiment, a fluid ejection device includes a substrate with a fluid slot, and a chamber layer over the substrate that defines a firing chamber and a fluidic channel extending through the firing chamber and in fluid communication with the slot at first and second ends. The device includes a tophat layer formed as a two-layer stack over the chamber layer, and a nozzle bore over the firing chamber that comprises a greater cavity formed in a first layer of the stack and a lesser cavity formed in a second layer of the stack, the greater cavity encompasses a larger volume than the lesser cavity.

Abstract: In an embodiment, a fluid ejection device includes a die substrate having first and second fluid slots along opposite substrate sides and separated by a substrate central region. First and second internal columns of closed chambers are associated with the first and second slots, respectively, and the internal columns are separated by the central region. Fluidic channels extending across the central region fluidically couple closed chambers from the first internal column with closed chambers from the second internal column. Pump actuators in each closed chamber pump fluid through the channels from slot to slot.

Abstract: An implantable medical device includes an actuator and/or sensor portion to be fixed to bodily tissue by means of a fixation mechanism, to act on the tissue and/or to detect a signal from the tissue, wherein at least one detector element, preferably a plurality of detector elements, adapted for detecting the close proximity of bodily tissue, is arranged on the actuator and/or sensor portion of the device, and an output of the or each detector element being connected or connectable to a detection signal evaluation unit for deriving a fixation state verification from detection signals provided by the or each detector element.

Abstract: A drop detection method comprises ejecting an ink drop that includes a fluorescent agent, illuminating the ink drop in flight with excitation light to excite the fluorescent agent, detecting fluorescence emitted by the drop in flight, having a longer wavelength than a wavelength of the excitation light, and, prior to such detecting, filtering out light having a shorter wavelength than the fluorescence wavelength; and a printer with drop detection assembly for performing the method.

Abstract: A method of monitoring nozzle condition in an array of inkjet nozzles comprises ejecting at least one black ink drop from an inkjet nozzle, wherein the black ink comprises a black colorant and a colloidal metal or metal-containing dopant. Light from a collimated light source is directed onto an ink drop-in-flight, and light-scatter from the drop is detected. The dopant increases light-scatter by the ink drop of an incident collimated light beam relative to the same ink without the dopant. From the detected light-scatter, an operational condition of the inkjet nozzle is determined. The dopant is visually undetectable in a printed mark made by the black ink, and the ink has a printed black optical density which is substantially the same as that of the same ink without the dopant.