I-Pen?

The Projection Feature

In the embodiment shown in patent FIG. 4 above, the tip of the stylus (#407) could include a transparent lens and tip assembly having a suitable conductive coating. The base module (#401) could also include projection circuitry (#402) operable to project an image through tip.

The lens assembly of the stylus tip could be operable to expand the beam from projection circuitry to project it onto a surface. The projection circuitry could include a projector or other suitable imaging device and suitable processing hardware or firmware to compensate for distortion incurred from projection circuitry to the projection surface.

In some examples, the projection circuitry could include a camera to image the projection surface for position detection by correlation (e.g., a technique similar to that used by optical mice) and/or to image an object (e.g., to provide scanner and/or camera functions).

Apple's patent FIG. 5 noted below presents us with a block diagram of one exemplary expansion module # 509 for providing a laser pointer functionality that could be used as an expansion module of modular stylus.

The expansion module could include a connector #516 for connecting expansion module to a base module which could include a connection interface. For example, the connector could include a threaded screw-type connector, plug-in connector, or the like. In some examples, the connector could include an interface (e.g., USB, SPI, I2C, RS232, and the like) that allows for the transfer of data and/or power between expansion module 509 and an attached base module.

Apple notes that the projection circuitry could include a light-source (e.g., laser, LED, digital light processing (DLP) projector, LCD projector, or the like), liquid crystal module (LCM) to modulate the light according to image data.

http://www.patentlyapple.com/patently-apple/2014/02/a-spectacular-ipen-patent-from-apple-surfaces-in-europe.html