Related Experiment Video
Updated: Jun 10, 2026
10:39
Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Analytic design of an achromatic double grating coupler
Applied Optics
|August 14, 2010
Summary
This study introduces a novel double grating design to couple polychromatic light from waveguides with minimal angular spread. The method analytically compensates chromatic dispersion, significantly broadening the usable wavelength range.
Area of Science:
- Optics and Photonics
- Waveguide Technology
- Nanophotonics
Background:
- Grating couplers are essential for integrating optical components.
- Conventional grating couplers suffer from significant angular dispersion, limiting their use with polychromatic light.
- Minimizing angular dispersion is critical for broadband applications.
Purpose of the Study:
- To present a new method for designing double gratings.
- To achieve negligible angular dispersion when coupling polychromatic waves out of a waveguide.
- To enhance the usable wavelength range of grating couplers.
Main Methods:
- Analytical calculation of two distinct grating functions.
- Designing the gratings to achieve dispersion compensation between the two elements.
- Simulating and analyzing the angular dispersion and wavelength range.
Main Results:
- A double grating design with negligible angular dispersion was achieved.
- The chromatic dispersion of the first grating is effectively compensated by the second.
- The usable wavelength range was increased by over two orders of magnitude compared to conventional couplers.
Conclusions:
- The proposed double grating method enables efficient broadband light coupling from waveguides.
- This design overcomes the limitations of conventional grating couplers for polychromatic applications.
- The technique offers a significant advancement in waveguide-to-free-space optical coupling.
