1. A portable camera device comprising: a first casing; a second casing containing a lens module and having a lower part connected to a first connecting position of said first casing such that said lens module is arranged above said first casing; and an extendable mechanism having a rear end with a document holding structure for holding a document and a front end connected to a second connecting position of said first casing via a first pivotal mechanism, wherein said extendable mechanism is selectively folded or unfolded with respect to said first casing when said extendable mechanism is rotated in various directions by adjusting said first pivotal mechanism, and a relative spatial correlation between said lens module and said document is adjusted such that said lens module is focused on a selected area of said document for capturing an image of said document.