Sogabe: I managed product design for the PRS-505. This is actually the second-generation Reader, after the PRS-500, and it has essentially the same internal structure as before. Despite this, I took on the task of making it even slimmer and easier to use.
Streamlining products without changing the internal structure is not usually an easy feat, but this time, development went very smoothly. In part that's because our engineers suggested making the case of extruded aluminum.
Normally, the circuit board is sandwiched between the front and back aluminum panels (each created by stamping), but inevitably, you end up with a thicker product to ensure durability and efficient assembly. In contrast, the PRS-505 case is seamless from the front panel to the back. This is single-body construction, with an aluminum panel shaped like a flat cylinder. Extruded metal makes the case very sturdy, and thanks to this, we made the body nearly 6 mm thinner.
Above all, extrusion was the only way to create these graceful, flowing contours. When the engineers first presented a sample of the extruded metal case, I had a feeling most of the design work was already finished. It was the perfect ingredient, so to speak; ready for some seasoning. Now it was time for a little ingenuity.
Sogabe: The Reader is a book, at heart. Too many buttons or other elements would make it look complicated and ruin its appearance. We sought the simplest layout possible. First, to show how the number buttons are directly linked to content rendered on the e-paper, we arranged them next to the screen. Pressing the round page button prominently positioned in the lower-left corner may remind users of paging through a book. We were careful to choose aluminum for the buttons as well, and the diamond-cut edge has a luxurious gleam.
There's another page button in the lower-right corner. We realized that some readers in North America fold the cover back (even when reading thick books) and hold books in their right hand, single-handedly. The button layout shows how we kept users with this habit in mind. But merely putting round buttons on a flat case seemed utterly uninspired. We tried button after button in various shapes, but each seemed to interrupt the surface; nothing was satisfying. It was frustrating, because the Reader would look neat and clean-cut without any buttons here at all, but adding buttons seemed to detract from its character and make it boring.
We finally eliminated this awkwardness by creating a distinctive curving surface along the right edge. This touch adds depth and expression to the appearance. Simple, but interesting from the combination of light and dark surfaces. Maybe I'm over-explaining it. It also recreates the feeling you get from resting your thumb on the edge of a book when reading, so it's a logical shape.