Flat Lens work- Better!
We all know that lens are round and circular, but do you know that scientists have come up with a new innovation- flat lens? And that they are even more effective?
The Harvard School of Engineering and Applied Sciences have created a 60 nanometers thick lens which is so thin, it is considered to be 2-dimensional. But this is not all. This new type of lens diffracts light even better than conventional curved-surface lens. Here's how it's made:
In conventional lenses, light slows down and there are delays to change its direction while it travels through the lenses, but for flat lens, the delay occurs immediately when the light hits the surface! A visiting graduate student from Italy commented that this invention could replace all the bulky components in many optical systems with flat lens.
Actually, from my perspective, not only this, but there is yet another advantage- since lesser materials will be involved in the making of optical instruments, there would be lesser waste on Earth! We are "reduc"-ing the wastes on Earth and lessening the chances of pollution!
I have often been concerned about too many types of lens using plastic. As plastic is non-biodegradable, extensive facilities and resources are required to recycle them. By reducing the plastic used in making optical instruments, plastic recycling would become more efficient and we take a step closer to a greener Earth!
- Scientists placed a very thin wafer of silicon with a nanometer-thin gold sheet
- Then, the gold sheet is partially stripped to leave behind a row of evenly-spaced V-shaped gaps
- A laser was shined onto the lens to test out its effectiveness, and, gold sheet comes into play. The gaps capture the incoming rays briefly before releasing them on the opposite side, with an improved precision compared to conventional lenses.
- Compared to conventional lenses, the flat lens offers an image free of defects like astigmatism, coma aberrations or the "fish eye" effect. The resulting image is incredibly sharp!
- What's better- the spacing of the gold sheet ("metasurface") can be altered to suit different wavelengths of light!
In conventional lenses, light slows down and there are delays to change its direction while it travels through the lenses, but for flat lens, the delay occurs immediately when the light hits the surface! A visiting graduate student from Italy commented that this invention could replace all the bulky components in many optical systems with flat lens.
Actually, from my perspective, not only this, but there is yet another advantage- since lesser materials will be involved in the making of optical instruments, there would be lesser waste on Earth! We are "reduc"-ing the wastes on Earth and lessening the chances of pollution!
I have often been concerned about too many types of lens using plastic. As plastic is non-biodegradable, extensive facilities and resources are required to recycle them. By reducing the plastic used in making optical instruments, plastic recycling would become more efficient and we take a step closer to a greener Earth!
To prove my point, watch this video for a practical proof