The telescopes of the future

Caltech has demonstrated a camera without lenses.

https://petapixel.com/2017/06/22/cal...camera-future/

quote
The camera has an arsenal of light receivers, each of which can
individually add a tightly controlled time delay to the light it
receives, allowing you to 'look' in different directions and focus on
different things in the scene in-front of the chip.

"We've created a single thin layer of integrated silicon photonics that
emulates the lens and sensor of a digital camera, reducing the thickness
and cost of digital cameras," says Ali Hajimiri, the leader of the team
looking into the camera. "It can mimic a regular lens, but can switch
from a fish-eye to a telephoto lens instantaneously -- with just a simple
adjustment in the way the array receives light."

The researchers at Caltech also think that the camera might have
implications for space photography. They envisage huge, flat telescopes
in Space or on the ground capable of imaging our universe.
end quote

Ground based huge telescopes are possible at an extreme low cost, since
the lenses are actually the most expensive part of the whole telescope.

Pointing is instantaneous, no wait to move heavy lenses. And since there
are no lenses, telescope can be made of huge dimensions, with much more
collecting power than what we can ever obtain with lenses.

The telescopes of the future may be just a sensitive wall of electronics.

[Mod. note: non-ASCII characters removed, please don't post non-ASCII
characters. It has been a long time since any professional telescope
had a large lens, nor do I think it's the case any more that the
optics are the most expensive part of the instrument -- mjh]