Thermal printers
AssigneeNorthern Telecom Limited
InventorsDavid R. Baraff, Lawrence H. Hobbs
Life of this patent
Estimating the term…
Abstract
Any element of a thermal print bar of resistive material is heated by a current pulse passed across the bar between an appropriate conductor pairing. Certain conductors are deposited in two parts with a rectifying layer deposited between the parts to provide diode isolation of heating paths from one another.
Claims12
A thermal printing device comprising an electrically insulating substrate supporting a film of resistive material and first and second conductor patterns electrically contacting said film of resistive material so as to establish resistive heating paths through said resistive material between closely spaced end parts of said first and second conductors, the conductors of the first pattern being matrix-addressed by a third pattern of conductors, the conductors of the third pattern electrically connected to respective sets of said first pattern of conductors at contact regions formed as rectifying junctions remote from the resistive material, the second and third conductor patterns being tailored for application of addressing signals.
A method of fabricating a thermal printing device comprises depositing onto an insulating substrate first and second patterns of addressing conductors and a pattern of linkage conductors, printing a strip of resistive material to establish resistive heating paths between the second addressing conductors and respective ones of the linkage conductors, depositing a rectifying layer over discrete areas of said first addressing conductors to form diodes, and depositing a third pattern of conductors to connect the diodes to respective ones of said linkage conductors.
Dependencies are inferred from the claim text.