A key device in all-optical networks is the optical filter. Ring resonator filters on the basis of GaInAsP / InP with improved filter response and increased functionality using integrated semiconductor optical amplifiers are presented. 2003 Optical Society of America OCIS codes: (130.3120) Integrated optics devices, (230.5750) Resonators

Optical blue filter is usually regarded as a critical optical component for high speed phosphor-based white light emitting diode (LED) visible-light-communication (VLC). However, the optical blue filter plays different roles in VLC when using modulations of on-off keying (OOK) or discrete multi-tone (DMT). We show that in the DMT VLC system, the blue optical filter may be unnecessary, and even ...

We first propose a multichannel optical filter with an ultra-narrow 3-dB bandwidth based on sampled Brillouin dynamic gratings (SBDGs). The multichannel optical filter is generated when an optical pulse interfaces with an optical pulse train based on an ordinary stimulated Brillouin scattering (SBS) process in a birefringent optical fiber. Multichannel optical filter based on SBDG is generated ...

A novel bandwidth tunable bandpass filter based on a silicon microring-MZI structure is proposed and demonstrated. By thermally tuning the resonance offset between the two microring resonators, and adding the two drop transmissions together, the bandwidth of the microring-MZI filter can be easily linearly tuned with low in-band ripples. Key words—bandwidth tunable; thermal tunable; optical filt...

introduction one of the most important pre-processing steps in optical coherence tomography (oct) is reducing speckle noise, resulting from multiple scattering of tissues, which degrades the quality of oct images. materials and methods the present study focused on speckle noise reduction and edge detection techniques. statistical filters with different masks and noise variances were applied on ...

The purpose of this study is to establish the technique for estimating optical flow with high accuracy and robustness using gradient-based method with local optimization. To obtain high accuracy, we should understand error sources and how to reduce the errors. We proposed error reduction techniques for gradient measurement error which are a spatiotemporal median filter to reduce sensor noise an...

In this contribution we develop a theoretical statistical approach to predict the acceptable bandwidth tolerances for optical filter cascades in wavelength division multiplexing (WDM) networks. We also establish tolerances for the center frequency misalignments considering a statistical approach presented in a previous work. The optical filters analyzed have a trapezoidal shape, and different b...