Re: Invention Time
In principle, if you had a sufficiently dense detector capable of recording not just the magnitude, but also the phase of the light wave, you can then compute the optical image your telescope would have got if it were perfectly focussed. You would still need to correct for atmospheric distortions, of course. An additional plus is that you won't actually need a mirror as such: you can process your data to form an image corresponding to the wavefront coming from any direction - and potentially observe all of them at once.
The downside is that even if can build a large enough sensor (say, soccer-field-sized) to beat a modern optical telescope, the amount of computing power you would need to synthesize your images at optical wavelengths is so enormous that this whole thing is currently firmly in the science fiction domain. At longer wavelengths used in radioastronomy both the sensor design and the amount of processing needed becomes practical. See: https://www.skatelescope.org/