Related Experiment Video
Updated: Jul 2, 2026
08:48
Writing Bragg Gratings in Multicore Fibers
Published on: April 20, 2016
Double groove broadband gratings.
Juha Pietarinen1, Tuomas Vallius
1Department of Physics and Mathematics, University of Joensuu, Joensuu, Finland. juha.pietarinen@nanocomp.fi
Optics Express
|September 6, 2008
Summary
This study uses wavelength-scale periodic structures for diffractive optics to broaden spectral bands. It leverages effective refractive index variations to counteract the efficiency drop of diffraction gratings with changing wavelengths.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Diffractive optics exhibit strong wavelength dependence, limiting their functional spectral band.
- Periodic structures at the wavelength scale offer potential for enhancing optical device performance.
Purpose of the Study:
- To increase the functional spectral band of diffractive optics.
- To compensate for the inherent wavelength dependence of diffraction grating efficiency.
Main Methods:
- Implementing waveguiding in wavelength-scale periodic structures.
- Utilizing the deviation of effective refractive index between waveguides as a function of wavelength.
Main Results:
- Successfully broadened the functional spectral band of diffractive optics.
- Demonstrated compensation for the strong wavelength dependence of diffraction grating efficiency.
Conclusions:
- Waveguiding in wavelength-scale periodic structures is an effective method to enhance the spectral performance of diffractive optics.
- Effective refractive index engineering in these structures provides a pathway to overcome limitations in diffraction grating efficiency across a wider spectrum.
More Related Videos
Related Concept Videos
01:26Phase Contrast and Differential Interference Contrast Microscopy
Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
01:17Bandpass Sampling
In signal processing, bandpass sampling is an effective technique for sampling signals that have most of their energy concentrated within a narrow frequency band. This type of signal is known as a bandpass signal. The key principle of bandpass sampling involves sampling the signal at a rate that is greater than twice the signal's bandwidth to prevent aliasing.
A bandpass signal has a spectrum with a lower frequency limit, denoted as ω1, and an upper frequency limit, denoted as ω2. The spectrum...
A bandpass signal has a spectrum with a lower frequency limit, denoted as ω1, and an upper frequency limit, denoted as ω2. The spectrum...
01:16Shear on the Horizontal Face of a Beam Element
To understand shear on the flat side of a prismatic beam element, consider the vertical and horizontal shearing forces, and the normal forces, acting on the element. The element's upper (U) and lower (L) sections, which are divided by the beam's neutral axis, are examined. The equilibrium of these forces is determined by applying the equilibrium equation, which helps identify the horizontal shearing force. This force is directly related to the bending moments and the cross-section's first...
01:27Passive Filters
Passive filters are utilized to shape the frequency spectrum of signals across a diverse array of applications. These filters, using only passive elements like resistors (R), inductors (L), and capacitors (C), are capable of selectively allowing or blocking certain frequency ranges without the need for external power sources.
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff frequency...
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff frequency...