
Why Don't We Build a Telescope Without Mirrors or Lenses? - sohkamyung
https://www.forbes.com/sites/startswithabang/2017/09/30/ask-ethan-why-dont-we-build-a-telescope-without-mirrors-or-lenses/#8b8ad985f30b
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gene-h
This is a very bad article. NASA has investigated how a lensless mirrorless
telescope could actually be made using photonic integrated circuits[0]. There
are even mass benefits too.

[0][https://www.nasa.gov/content/low-mass-planar-photonic-
imagin...](https://www.nasa.gov/content/low-mass-planar-photonic-imaging-
sensor-1)

~~~
danielvf
Still has lenslets, but really fricking cool! Thanks for the link.

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danielvf
If this sounded like a bad idea to you, and you wondered what new tech made
this possible - there is no new tech mentioned and you can safely skip the
article.

It’s basically just a list of reasons why this does not work at all.

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ararar
I thought they were going to talk about diffractive optic telescopes which
require neither lenses or mirrors. See more here
[https://str.llnl.gov/str/March03/pdfs/03_03.2.pdf](https://str.llnl.gov/str/March03/pdfs/03_03.2.pdf).
Someone did not do their research! The aragoscope is mentioned in the
Spacetime episode mentioned elsewhere here.

~~~
planteen
There is also a sensor stack for different wavelengths that is actually
realized, not a pipe dream like the article makes it seem:
[https://en.wikipedia.org/wiki/Foveon_X3_sensor](https://en.wikipedia.org/wiki/Foveon_X3_sensor)

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amelius
Like this one?

[http://www.lofar.org/about-lofar/general-
information/introdu...](http://www.lofar.org/about-lofar/general-
information/introduction)

~~~
vanderZwan
Aaaah, LOFAR, also known among the students of Groningen from 2005 as _" the
reason why I can download at 15MiB per second for 10 Euros per month"_.

(They implemented the data infrastructure before the sensors were active, so
there was a _lot_ of bandwidth to spare. No idea how things are now)

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dsr_
Because it's really hard to arrange for gravitational lenses in the directions
and distances you want to observe?

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danbruc
This PBS Space Time episode [1] covers quite a few possible designs for space
telescopes without heavy lenses or mirrors.

[1]
[https://m.youtube.com/watch?v=BIASPc89Sgk](https://m.youtube.com/watch?v=BIASPc89Sgk)

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wronex
How about phased arrays? [http://m.caltech.edu/news/ultra-thin-camera-creates-
images-w...](http://m.caltech.edu/news/ultra-thin-camera-creates-images-
without-lenses-78731)

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kwhitefoot
It's not:

    
    
        	Why Don't We Build a Telescope Without Mirrors or Lenses?
    

It's:

    
    
        	Why We Don't Build a Telescope Without Mirrors or Lenses.

