in between the two transmitting end regions, the transmitting inductor coil configured to generate
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`time-varying magnetic flux through the transmitting ferromagnetic structure. The receiving
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`element can include a ferromagnetic structure having a groove region defining two end regions
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`on opposing sides of the groove region, each end region comprising respective interface surfaces,
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`wherein the groove region has a smaller length than the two end regions. The receiving element
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`can further include an inductor coil wound about the groove region of the ferromagnetic structure
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`and in between the two end regions, a shield comprising a plurality of sidewalls and a back wall
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`that form a cavity within which the ferromagnetic structure and inductor coil are positioned, and
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`a spacer positioned between the ferromagnetic structure and the shield to attach the
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`10
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`ferromagnetic structure to the shield.
`
`[0008]
`
`In certain embodiments, a stylus for inputting data into a host device includes a housing
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`comprising a curved portion and a flat portion, power receiving circuitry disposed within the
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`housing, a receiving element disposed within the housing and coupled to the power receiving
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`circuitry, and an operating system coupled to the power receiving circuitry and the receiving
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`element, and configured to operate the power receiving circuitry and the receiving element to
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`receive power from the host device. The receiving element includes a ferromagnetic structure
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`having a groove region defining two end regions on opposing sides of the groove region, where
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`each end region includes respective interface surfaces, and the groove region has a smaller length
`
`than the two end regions. The receiving element can further include an inductor coil wound
`
`about the groove region of the ferromagnetic structure and in between the two end regions,
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`where the length of the groove region is a dimension that extends along a direction perpendicular
`
`to the aXis of the inductor coil. The receiving element can also include a shield comprising a
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`plurality of sidewalls and a back wall that form a cavity within which the ferromagnetic structure
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`and inductor coil are positioned, and a spacer positioned between the ferromagnetic structure and
`
`the shield to attach the ferromagnetic structure to the shield.
`
`[0009]
`
`In some embodiments, an alignment device includes a center magnet having poles
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`arranged in a vertical orientation, first and second strengthening magnets disposed on opposite
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`ends of the center magnet, where the first and second strengthening magnets having poles
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`arranged in a horizontal orientation, and first and second ferromagnetic structures disposed on
`
`outer ends of corresponding first and second strengthening magnets such that the first
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`15
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`20
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`25
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`30
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`