Paper holder for smartphone document scan

The problem with scanning documents with a smartphone is that documents are never really straight.
Using a finger or a book to help often results in an ugly edge.
To solve this problem, I designed these two clamp holders for straightening and holding documents for scanning with a smartphone.

There is no fixed grid, so it can be used with complete flexibility. Very unruly documents can be inserted deeper, while others only need the edge.
There is also enough space for thicker stacks of documents, which may be bound together.

Ideally, you print it in white so that there is neither a thick shadow nor an ugly border on the final document.