What is subwavelength grating?
SWGs are grating structures with a period Λ that is sufficiently small compared to the wavelength of light. They are formed by a periodic arrangement (with period Λ) of high refractive index material with a thickness a implanted into a low refractive index material (the duty cycle of the SWG is defined as D = a/Λ).
What is sub wavelength?
Definition. Sub-wavelength optics is the study of light on a spatial scale smaller than its wavelength. Conventionally, the minimum length scale on which a beam of light can operate is equal to half its wavelength.
What is sub wavelength imaging?
Subwavelength imaging can be defined as optical microscopy with the ability to see details of an object or organism below the wavelength of visible light (see discussion in the above sections). In other words, to have the capability to observe, in real time, below 200 nanometers.
What is the inverse of wavelength?
spatial frequency
The inverse of the wavelength is called the spatial frequency. Wavelength is commonly designated by the Greek letter lambda (λ). The term wavelength is also sometimes applied to modulated waves, and to the sinusoidal envelopes of modulated waves or waves formed by interference of several sinusoids.
How does a Metalens work?
A metalens is made by depositing an array of subwavelength “pillars” of a high-index material on a flat substrate on the order of a millimeter thick, with both materials transparent at the transmitted wavelength.
How does a Superlens work?
Superlensing results from the enhancement of evanescent waves by surface plasmons. The key to the superlens is its ability to significantly enhance and recover the evanescent waves that carry information at very small scales. This enables imaging well below the diffraction limit.
Which color has the longest wavelength?
red light
On one end of the spectrum is red light, with the longest wavelength. Blue or violet light has the shortest wavelength. White light is a combination of all colors in the color spectrum. It has all the colors of the rainbow.
What is relationship between frequency and wavelength?
Frequency and wavelength are inversely proportional to each other. The wave with the greatest frequency has the shortest wavelength. Twice the frequency means one-half the wavelength.
What is a Metalens?
Metalenses are flat surfaces that use nanostructures to focus light. These simple, flat surface lenses could replace bulky, curved lenses currently used in optical devices.
How do you make Metalens?
How are metamaterials used?
Potential applications of metamaterials are diverse and include optical filters, medical devices, remote aerospace applications, sensor detection and infrastructure monitoring, smart solar power management, crowd control, radomes, high-frequency battlefield communication and lenses for high-gain antennas, improving …
What is a hyper lens?
hyperlens (plural hyperlenses) (optics) A nanostructured metamaterial that produces magnified images of objects smaller than the wavelength of the light used.