Hewlett-packard Development Company, L.p.

Other

David Douglas Hall

Donald W Schulte

Terry E McMahon

Rio Rivas

Ed Friesen

Terry Mcmahon

Chien-Hua Chen

Gerrit Jan Van Der Kolk

Gerald F Hein

Ying-Chih Liao

Michael J J Eerden

Antonius P Hurkmans

William T McCarthy

Garret Hull

Rivas Rio

A fluid ejection device may include a substrate having front and back opposing surfaces and a slot extending through the substrate between the back and front surfaces and along an axis of the substrate. A recessed end region may be formed in the back surface at each end of the slot.

Printhead with recessed slot ends

In an embodiment, a method of forming a printhead includes forming on a front-side surface of a substrate, a thin film layer and a plurality of fluidic channels and ejection chambers. The method also includes forming a slot through the substrate from the back-side surface to the front-side surface, where the back-side and front-side surfaces generally oppose one another. The slot has a length extending along a long axis of the substrate and a width extending along a short axis of the substrate. The method includes forming recessed regions into the back-side surface of the substrate at both ends of the slot that extend beyond the length of the slot.

A method of determining a healthy fluid ejection nozzle includes measuring changes in impedance across the nozzle as fluid passes through it. A printhead includes a metal probe that intersects an ink nozzle and an integrated circuit to sense a change in impedance across the nozzle through the metal probe.

Determining a healthy fluid ejection nozzle

A method of storing data in an array of circuit elements, said method comprising injecting a current into selected circuit elements, said current causing a persistent change in a resistance of said selected circuit elements from a first resistance to a second higher resistance indicative of a binary data bit, wherein said current does not break an electrical circuit in which said circuit element is disposed.

Data storage in circuit elements with changed resistance

In one embodiment, a method provides a bipolar junction transistor that is coupled to a first power supply. A second power supply is utilized to turn on the bipolar junction transistor. And, the bipolar junction transistor is overdriven.

Transistor antifuse device

Method of applying a coating by physical vapor deposition

A bowstring mounted peep sight is disclosed having a peep housing that is frictionally located between displaced bowstring filaments. The peep housing defines a peep hole and a transverse oriented receiving slot. Insertable aperture reducing discs are slidably inserted into the receiving slot to incrementally decrease the relative aperture of the peep hole. To prevent the inserts from being inadvertently dislodged from the receiving slot during use of the invention, one of the displaced bowstring elements is positioned so as to prevent the disc from sliding outwardly therefrom. Because of the design of the peep housing, lightweight materials can be utilized. Frusto conical recesses on both planar surfaces of the peep housing reduce incidental glare thereby increasing the clarity of the observed target.

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Corvallis, OR, United States of America

David Douglas Hall