NASA puts lenses through a different drill to stare at the Sun

NASA Goddard boffins and engineers have taken inspiration from the Fresnel lens to craft a “photon sieve” they hope will help them observe the processes that heat the sun's corona. The diffraction that gives a Fresnel lamp its soft edges is also handy for gathering light. NASA's post here explains that after passing through …

[Tom 7]

Old hat

My tin foil hat has used this technology for years allowing me to focus my thoughts on approaching alien vessels and repulse them. It works quite well!

[Anonymous Coward]

Re: Old hat

or are we....I mean, or are they here? Perhaps you need more and smaller holes in your tinfoil.

[Anonymous Coward]

Re: Old hat

@Tom

Same here!

Mrs C also finds the design useful - for draining spaghetti etc. Once I've finished repulsing aliens of course.

[Captain Scarlet]

Re: Old hat

Hmm I wondered why the Mysterons were returning all Starchy and plotting to destroy the Dolmio Puppets.

[Simon Harris]

16 million holes?

That's even more holes than in Blackburn, Lancashire!

[Paul Smith]

Re: 16 million holes?

I would like to propose the Albert Hall as the new El Reg unit of measure for counting holes. "Now we know how many holes it takes to fill the Albert Hall."

[TitterYeNot]

Re: 16 million holes?

"I would like to propose the Albert Hall as the new El Reg unit of measure for counting holes."

Allegedly, senior staff working at the Albert Hall in the late 60's strongly objected to the lyrics of 'A Day In The Life', and wrote to Brian Epstein to complain. Supposedly they thought that the general public would take the song literally and think that:-

a. There were 4 thousand holes in the Albert Hall.

b. That the Albert Hall was in Blackburn, Lancashire.

c. That the singer would love to 'turn on' the Albert Hall.

And after John Lennon's refusal to change the lyrics, the song was banned from ever being performed at the Albert Hall. I'm pretty sure it's a windup - but if not, it's proof that there was at least one hole in the Albert Hall, of a type beginning with arse...

http://www.royalalberthall.com/about-the-hall/news/2015/april/royal-albert-hall-was-furious-over-beatles-lyric-newly-discovered-documents-reveal/

[ArrZarr]

Re: 16 million holes?

Have you noticed the date that letter was revealed?

[Doctor Syntax]

AIUI Fresnel lenses and plates are different items. The lens is a refraction device and the plate a diffraction device. A Fresnel lamp is is one that uses a Fresnel lens with stippling on the the flat back of the lens to break up the ring pattern which would be apparent in the projected spot. The original Fresnel lenses used in lighthouses aren't usually stippled - nobody's looking at what the projected light looks like.

[DropBear]

Quite. I was looking at the image going "what has this got to do with a Fresnel lens?!?"

[Little Mouse]

I was going to post a comment sooner

...but was unable to look away from those two hypnotic eyes...

[Anonymous Coward]

Fresnel zpne plate not a fresnel lens

What is described is a fresnel zone plate, This uses diffraction. A fresnel lens is, as the name suggets a lens, but one constructed with cocentric toroidal sections.

Sorry to be pedantic.

[Will Godfrey]

Re: Fresnel zpne plate not a fresnel lens

Indeed so.

I can remember when you could get a fresnel lens to make your 9 inch (B&W) TV screen look more like a 14 inch one.

Coat, cos you've got to be an oldie to remember them.

[Doctor Syntax]

Re: Fresnel zpne plate not a fresnel lens

"I can remember when you could get a fresnel lens to make your 9 inch (B&W) TV screen look more like a 14 inch one."

I can remember a cousin having a non-Fresnel lens for that purpose. To save material it was a hollow plastic moulding which the owner had to fill up with water. And the set was more black & green then B&W.