metal lens Focusing

Metal Lens – Discover How a Metalens Works – Dec, 2020

metal lens FocusingMetal Lenses are designed to deal with shortcomings of glass lenses such as Chromatic aberration. According to researchers at Harvard, metal lenses will help to get rid of issues we experience with glass lenses.

They include heavy lenses, chromatic aberration (blurry images with rainbow-colored edges), high production costs, and the need to use glass prisms.

In this metal lens article:

  • Harvard researchers invent thinner than glass metal lens.
  • The metal lens is made of microscopic metal pillars that focus light.
  • Unlike glass lenses, metal lens can focus light without creating blurry images.
  • The Titanium dioxide Metal Lenses can make lightweight and compact optic devices.

Metal Lens Applications

Metal Lens Light FocusingWhile the team has not finalized plans commercialize it yet, they have already tested the ultra-thin and lightweight metal lenses in the lab. They performed much better than glass lenses when focusing light, but have a lower light transmission efficiency, at 20%. Some of the applications of metal lenses could include:

  • Phone Cameras
  • Cameras
  • Binoculars
  • Eye Glasses
  • Telescopes
  • Scope

How Metal Lenses are Made?

The Harvard researchers used titanium dioxide to make metal nanopillar arrays, (which simply means they made a field of microscopic metal pillars). These pillars are made using a technique called single step lithography, which is similar to nano-imprinting.

That means once the researchers perfect the metalens, it can also be mass-produced using nano-imprinting. Currently, the Harvard Office of Technology is working to commercialize the product through a Tech-Startup.

How Do Metal Lenses Work?

Metal Lens Titanium Dioxide DesignMetal lenses use the nano metal pillars to “bend” light, thereby helping to focus or disperse it. The current metal lenses can work light frequencies ranging from blue to green, in the light spectrum.

The metal lens can focus light of wavelengths 490nm to 550nm, (blue to green light spectrum).

The researchers are working to make the material work with a larger light spectrum, from red to violet. If they succeed, the metal lenses are going to change how we make cameras, radically.

The metal lens material can be cheaper to make, and the images it projects will be of much better quality.

So far, they have succeeded to make it work in a continuous light spectrum of blue to green, which is sufficient to handle light for LED light sources. They also hope to scale the metalens’s size to 1cm.

The research team made the titanium dioxide metal lens while under the guidance of Professor Carpasso, in his Harvard laboratory.

Problems Solved by Metal Lenses

Metal Lens Nano PillarsThe main problem the metal lenses are going to solve is chromatic aberration, and lens weight. Glass lenses force light wavelengths passing through them at different speeds to spread out.

We also call this phenomenon color fringing. That causes images to appear blurry or their edges to appear colored.

The titanium dioxide metal lens has successfully focused a single wavelength of light without causing aberration.

That has solved the issue of aberration, which is a major shortcoming of glass lenses.

Can You See Through a Meta Lens?

Yes, you can see through a metalens, because they space the nano pillars widely. That gives the metallens a wide mesh-like structure.

There are currently many surfaces that have thin metal film coats. These include anti-UV and Infrared glass surfaces. Overall, this technology will change the size, look, and performance of optical devices.

These allow light of other wavelengths to pass through, but block UV and infrared lights. And still they therefore appear clear, and you can see through them.

Metal Lens

Conclusion – Metal Lens Article

What are your expectations and concerns about metal lenses? Please share your comments in the comment section below.

 

 

 

Sources:

https://www.nature.com/articles/s41565-017-0034-6

https://www.seas.harvard.edu/news/2018/01/single-metalens-focuses-all-colors-rainbow-one-point

https://meckshome.com/outdoor-led-flood-light-bulbs-150-watt-equivalent/

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