A second RIM patent documenting a smartphone where the keyboard is hidden on a sliding panel has been published, submitted a month later than the first we saw at the beginning of February.� Titled “Hybrid portrait-landscape handheld device with trackball navigation and hide-away keyboard” the patent�describes a smartphone similar to HTC’s TyTN, with its QWERTY keyboard sliding out from behind the screen, only with the BlackBerry trackball instead of a D-pad.��RIM describe the handset as being used in portrait mode for calls and reading messages, and suggest a touchscreen and/or voice control could be used when the keyboard is not extended.

The design would also allow for a larger screen than is currently available in RIM’s range, without significantly increasing the size of the whole handset.� While BlackBerry models have traditionally been candybar in format, recent attempts to slim down the design - in the shape of the Pearl - have resulted in a relatively cramped keyboard.

[via Electronista]