We present a perfect graphene absorber with a compound waveguide grating at the near-infrared. The analytical approach is mainly based on the coupled leaky mode theory, which turns the design of the absorber to finding out the req

We present a high-sensitivity fiber Bragg grating (FBG)-based microphone with a flat response and static pressure equalization. A very high dynamic sensitivity of the microphone is achieved by a pressure sensing structure based on

In an erbium-doped fiber amplifier (EDFA), erbium ions act as a three-level system. Therefore, much higher pump energy is required to achieve the population inversion in an erbium-doped fiber (EDF). This higher pump energy require

For Brillouin optical time-domain analysis (BOTDA) based on distributed Brillouin amplification (DBA), constant Brillouin response achieved by the exponentially variable bandwidth/intensity pump modulation suffers from the much lo

We propose a switchable multi-wavelength erbium-doped fiber laser based on a four-mode fiber Bragg grating (FBG). The four-mode FBG is fabricated in a hydrogen pre-loaded fiber by the phase mask method, which can support four line

We propose and investigate the use of a Kramers–Kronig (KK) receiver in a single sideband orthogonal frequency division multiplexing radio over fiber (SSB-OFDM-RoF) link based on an optical remote heterodyne solution. This scheme

This Letter proposes a snapshot imaging spectrometer, which obtains the spectral information and spatial information in one “shot”. The device proposed can achieve the data cube size of 21×29×40 in the waveband of 400–800 nm. The

Single layer lattice graphene deposited on the metal substrate can hardly be imaged by the optical microscope. In this Letter, a large field-of-view imaging ellipsometer is introduced to image single layer graphene which is deposi

A double-pass grating imaging spectrometer is proposed and demonstrated. The traditional entrance slit is replaced by a middle reflective slit, which is used as a spectral filter rather than a spatial filter. The light from the sc

We report a method for simultaneously and directly measuring all six-degrees-of-freedom (six-DOF) motion errors of a rotary axis. Such a method combines the principles of laser interferometry and laser collimation measurement. One

The first Asia-Pacific Comparison of Absolute Gravimeters (APMP.M.G-K1) was organized by the National Institute of Metrology (NIM) of China from December 21, 2015 to March 25, 2016 in Changping, Beijing. Our compact cold atom grav

A modified spectral beam combining (SBC) approach based on double asymmetrical filters was proposed. By using this scheme, the high-order lateral modes at the edge of the far-field pattern can be suppressed in the external cavity,

This study investigates the applicability of a few-layer structure ReSe2 as a saturable absorber (SA) for demonstrating a passively Q-switched pulse laser. The ReSe2 SA had a modulation depth of 6.86%. The Q-switched experiment wa

We propose a fast and accurate automated algorithm to segment retinal pigment epithelium and internal limiting membrane layers from spectral domain optical coherence tomography (SDOCT) B-scan images. A hybrid algorithm, which comb

In this Letter, we present an electrically tunable holographic waveguide display (HWD) based on two slanted holographic polymer dispersed liquid crystal (HPDLC) gratings. Experimental results show that a see-through effect is obta

A method for calculating the atmospheric parameters measurement accuracy requirement based on polarized reflectance retrieval is proposed. The at-sensor polarization states with different atmospheric parameters content are simulat

Over the last years, there has been tremendous progress with compact pulsed lasers based on various solid-state gain media, such as crystals and glasses doped with laser-active ions. With the integration of increasingly diverse sa

Electromagnetically induced transparency (EIT), a typical quantum interference effect, has been extensively investigated in coherent atomic gases. In recent years, it has been recognized that the plasmonic analog of atomic EIT, ca