Here's the real deal on "digital" lenses.
Old-fashioned film lenses have smaller back elements, which means the light falls on the sensor at an oblique angle. Sensor cells, however, "look" straight ahead. The wider back element allows the light to fall on the sensor at a less oblique angle, allowing for more even exposure on the edges.
My old film lenses work quite well, but the newer "digital" lenses from Nikon are just superb on the digital camera. They also work great on film.
There you have it. Demystified digital.
In the end, though, just making a big back element isn't enough. All the art of lens-making has to be incorporated to create a great lens. So far, I've been delighted with lenses from Nikon and Tamron, all of which were redesigned for digital.
But some of the older AF lenses just happened to have similarly large rear optics, making them naturals to be adopted for digital shooting.