Abstract: A substrate for the print head of an ink jet printer includes a plastic base, a metallization layer overlying the plastic base, and a dielectric structure overlying the metallization layer. A thin film resistor is deposited over the substrate, as required. Preferred materials include polyimide plastic for the base, chromium for the metallization layer, and a bilayer construction of silicon dioxide overlying titanium for the dielectric structure.

Abstract: Disclosed is an improved thermal ink jet print head with an amorphous diffusion barrier that inhibits corrosion associated with ink. The head has a silicon substrate, a silicon dioxide insulating layer, a tantalum aluminum alloy (TaAl) resistive layer, and two separated gold conductive regions formed over the resistive layer. Ink is drawn into a channel bounded above by an orifice plate and below by the TaAl exposed between the two separated gold regions. The ink is superheated and expelled as fine droplets through the orifice plate. The invention minimizes corrosion by placing a thin corrosion-resistant layer of amorphous metallic alloy over the conductive layer, thereby improving durability of the print head.

Abstract: A coating is applied to an optical fiber to form a thin hermetic seal. The coating is preferably applied on-line by a process such as chemical vapor deposition. The coating retains its integrity under extreme conditions of temperature and pressure thereby expanding the range of uses of optical fibers.

Abstract: An optical switch having low insertion loss and low crosstalk is provided by two slabs of birefringent material having a polarization rotator as a control element interposed therebetween. By controlling the polarization rotator electrically, a selectable ratio of transmitted-to-displaced output optical power is realized. The optical switch therefore can function as an attenuator to a light beam traversing through it. In the preferred embodiment calcite crystals are used for the slabs, and a liquid crystal cell for the polarization rotator.