Amazon.com launched two new Kindles in quick succession this year. So what will its next electronic reader look like? How about one that works with an electronic pen? Amazon recently received a patent for an "electronic input device such as an electronic pen" that can be used to annotate paper documents and locate the corresponding digital version.

The utility patent, No. 7,546,524, was granted June 9 and lists its inventors as Colin Bryar, Hilliard Siegel, and Steven Kessel. The original patent application was filed on March 30, 2005.

The patent describes an "Electronic input device, system, and method using human-comprehensible content to automatically correlate an annotation of a paper document with a digital version of the document."

Here's more description from the abstract:

An electronic input device such as an electronic pen is provided to annotate a paper document. The input device records an annotation and an image of human-comprehensible content in the document sufficient to identify the document and possibly a location in the document. The human-comprehensible content is used to locate a digital version of the document and determine a corresponding location of the annotation in the digital version of the document. A computer system such as a server system may receive and store the annotation in association with the digital version of the document. The server system may further augment the digital version of the document with the annotation and send the augmented version to an output device for display and/or printing.

Amazon spokeswoman Patty Smith declined to comment. Current Kindles, including the new DX, aren't touch screen, but if they ever go that route, an electronic pen or stylus would be an interesting addition. The idea of scanning printed books and newspapers -- and finding electronic versions on the Kindle or other devices -- could be a powerful feature too, driving more sales of digital content.

Here's another image from the Amazon patent filing:

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