New Type of Lens

[Mr Spock]

Intriguing. A new kind of flat lens made of transparent quartz which could replace conventional glass lenses.

Flat Lens

[swamp thing]

Very interesting article, thanks Michael  

[symesie04]

Yes have been reading that. Sounds great for both conventional photography and of course for astronomy both visual and photography. Interesting it can be adapted to provide infa red and ultra violet wave lengths. Also it is cheap to scale once tools are in place. So in the near future we could be be doing astrophotography with unparalleled sharpness across every spectrum of light using 3m fracs! get in 

[michael.h.f.wilkinson]

Interesting development, but I mainly see applications for very small lenses (microscopy, perhaps EPs). Very thin lenses of very large size bend (this limits the size of refractors in quite a fundamental way).

[Alien 13]

I have been wondering about these kind of possibilities for years along with using DLP technology for mirrors,  its not often that we get a potential game changing breakthrough but it does happen.

Alan

[Knighty2112]

Interesting to see where this technology goes in regards to astronomy. Pretty sure that stability issues could be worked out for larger lenses, but time will tell I guess.  

[Chris]

25 minutes ago, michael.h.f.wilkinson said:

Interesting development, but I mainly see applications for very small lenses (microscopy, perhaps EPs). Very thin lenses of very large size bend (this limits the size of refractors in quite a fundamental way).

I thought this, but in the blurb the author says " want to make a 12" lens, no problem". The future of optics could be very interesting, although the purist in me would probably miss the art and engineering of conventional lenses. 

[Alien 13]

I would think the big mobile phone company's might jump on this possibly with an integrated sensor, who knows in perhaps 10 years a mobile might be able to take a snap of the night sky that is outstanding or true broadcast quality video.

Alan

[CraigT82]

I wonder what the light throughput would be....Potentially very close to 100%? Would make great DSO hunting fracs. 

Wonder when the Televue 'Nano' EP will be released! 

[symesie04]

46 minutes ago, michael.h.f.wilkinson said:

Interesting development, but I mainly see applications for very small lenses (microscopy, perhaps EPs). Very thin lenses of very large size bend (this limits the size of refractors in quite a fundamental way).

As others have mentioned im sure they could engineer a way to provide a rigid frame for enlarged lenses. Perhaps a layer of Graphene or perhaps genetically engineered spider silk. Besides flex is only bad when applied to things that are designed to be rigid right?

[Mr Spock]

I think we need to throw out the window any knowledge we might have on how glass and lenses behave. This is new technology and has it's own new areas of knowledge we as yet know little of.

[John]

6 minutes ago, Mr Spock said:

I think we need to throw out the window any knowledge we might have on how glass and lenses behave. This is new technology and has it's own new areas of knowledge we as yet know little of.

I think this is right. All the stuff about glass types, abbe numbers, etc, etc won't relate to the these new technologies I guess.

Perhaps we might end up with programmable / adaptive optics where we can select the optical charactersics on the fly to suit the intended use, target, conditions etc ?.

 

[Alien 13]

The technology could be well suited to bionic eye implants but as said it could open up completely new areas.

Alan

[michael.h.f.wilkinson]

It is very interesting, but I want to know more about how the imaging works, and what the throughput is. The authors state different sized bumps yield different effective focal lengths. My physics instincts tell me the size of the bumps matters in relation to the wavelength of light, so I wonder whether CA will be an issue. I will try to dig up the physics behind this, and check whether this instinct is correct.

[Mr Spock]

The article says the design doesn't suffer from the usual aberrations. Also that the thickness of the 'lens' is less than the wavelength of light (I'll assume they mean at the short end).

[Stub Mandrel]

Probably the biggest cost will be putting one of these between two sheets of optically flat glass to support it and protect from sticky fingers.

[DaveS]

Hmmm 12" f/5 absolutely apo 'frac, polystrehl near 1.0 and no need of a field flattener or central obstruction.

Yes please, where do I sign?

[barkis]

The demise of the diffraction spot?  I can't get my head around that.                       This isn't fantasy is it?. 

[barkis]

I think space borne giant optical windows will revolutionize the search for ET.  Well,  someone else was bound to raise the subject . 

[Peter Drew]

I didn't notice a mention of 12" diameter, just 12", non astro boffins might well mean 12" focus. The application for microscope or camera lenses does seem an exciting prospect but don't put your Dob on eBay just yet! 

[acey]

12 hours ago, michael.h.f.wilkinson said:

It is very interesting, but I want to know more about how the imaging works, and what the throughput is.

Here's their paper:

https://arxiv.org/ftp/arxiv/papers/1605/1605.02248.pdf

The lenses are designed to work at specific wavelengths, they're for imaging rather than visual use, and the prototype is 2mm across. Quotes from paper:

Chromatic aberrations in our meta-lens are more pronounced than the lenses based on refractive optics, resulting in a wavelength-dependent focal length (Fig. S5A). This is generally not an issue for laser-related imaging, microscopy, and spectroscopy because monochromatic sources with narrow linewidths are used.

 

Imaging demonstration.

In order to demonstrate the use of our meta-lens for practical imaging, we fabricated a meta-lens with diameter D = 2 mm and focal length f = 0.725mm giving NA = 0.8. First, we characterized the imaging resolution using the 1951 United States Air Force (USAF) resolution test chart (Thorlabs Inc.) as the target object. The measurement configuration is shown in Fig. S6. Figure 4A shows the image formed by the meta-lens. The light source was a tunable laser (SuperK Varia) set at 530 nm with a bandwidth of 5 nm.

 

Not much use for astronomy, then.

 

[Steven Bruner]

19 hours ago, Mr Spock said:

Intriguing. A new kind of flat lens made of transparent quartz which could replace conventional glass lenses.

Flat Lens

Amazing, simply amazing !  Thanks for sharing this with us.