Microlenses were invented and put on your DSLR sensors because they couldn't make curved sensors.
AFAIK, the purpose of microlenses is actually to work around the fact that the sensors aren't flat, but rather recessed down into pockets in the silicon. Light rays near the edge of the sensor would otherwise fall way off unless you use a huge image circle. Changing the angle of those pockets might provide an advantage over the microlenses, but doing so doesn't inherently require curving the actual face of the sensor.
Where do you read such garbage? The purpose of the microlens is to increase the light gathering surface of the pixel, so that the space on the sensor top where there is circuitry and other stuff between pixels can be used to gather light to send into the pixel. This problem becomes more acute towards the edge of the sensor because rays of light are striking the sensor at and angle.
That's certainly an added benefit, but what I said is quite correct; unless you're using a back-illuminated sensor
, the actual light-sensitive part of the chip is inherently recessed below the wiring. This results in light fall-off near the edges if you don't have microlenses.
Don't believe me? Read Leica's description of their microlenses array:
"This optimized micro lens design, based on many years of precision optical engineering experience, captures and concentrates even the most oblique rays on the sensor and reliably prevents image brightness fall-off at the edges and corners of the image."
Their words, not mine.
On the other hand, using a curved sensor brings with it a lot of other problems. For starters, the screen you show the image on isn't curved, and neither is the photo paper. So the image would have to be warped to fit the medium. Even ignoring all the aliasing problems that will likely cause (which I'd expect to be considerable), unless I'm mis-thinking this, the resolution on the photo will probably be lower near the edges of the sensor—built-in corner softness, if you will—unless the pixel density changes as you get closer to the edge of the sensor, in which case the SNR will be worse near the center of the photo. Neither approach seems particularly desirable. Or maybe I'm missing something.
Sounds like you're over thinking this in order to find reasons that it isn't a good idea as you're wrong about everything.
Build a pin hole camera with your lens or just some big pieces of cardboard and see what happens out the back.
Yes, you can use a flat focal plane, which produces vignetting, or a curved focal plane, which results in distortion. I'm not seeing your point here.