In this letter, we discuss the increase in the average cluster size by lowering the stagnation temperature of the methane (CH4) gas. The Coulomb explosion experiments are conducted to estimate the cluster size and the size distrib

Detection of underwater bubbles is one of the key issues of the research of ocean-atmosphere flux exchange. Digital holographic experiment is carried out based on Mach-Zehnder digital holographic system, to detect the distribution

In order to test convex aspheric surfaces without the aid of other null optics, a novel method combined sub-aperture stitching and interferometry called SSI (sub-aperture stitching interferometry) is introduced. In this letter, th

The hysteresis nonlinearity of piezoelectric actuator is one of the main defects in the control of deformable mirror which is widely used as a key component in adaptive optics system. This letter put forward a modified Prandtl-Ish

In a certain amplification system, signal laser can be amplified from 1 nJ to 5 J. To realize a high quality imaging transfer, meet beam diameter expansion requirement, and get good filtering effects, three spatial filters are des

Three-dimensional (3D) simulations and theoretical analyses on super-short pulse generated using freeelectron lasers (FELs) at perfect synchronism are carried out with the help of our 3D OSIFEL code. The evolution of longitudinal

In this letter, the influence on the beam quality due to cumulative effect of the inner channel thermal deformation in the high energy laser system with unstable resonator is researched. Firstly, three typical laser powers of 50,

A mode locked Er-doped fiber laser based on a single-wall carbon nanotube saturable absorber is demonstrated. A high quality single-wall carbon nanotubes (SWCNTs) absorber film is fabricated by a polymer composite. The pulse durat

A method to shape the incident laser beam into a concentric multi-ring pattern with different intensity distribution is presented based on geometrical transform method and energy conservation. The output two and three rings are de

We present a novel technique to generate an orthogonally polarized optical single sideband (OSSB) generated by a tunable bandpass filter (TBF).When the OSSB passes through the other polarization modulation (PolM) which is polariza

A novel fiber Bragg grating (FBG) sensing system based on code division multiple access (CDMA) technology is proposed. CDMA is used to separate each reflected sensor. Simulation of experimental results indicates the CDMA technolog

In this letter, the theoretical model and rate equations of Ytterbium-doped double-clad fiber amplifiers are introduced. The output performance of fiber amplifiers is analyzed through numerical simulations considering three main f

A novel kind of octagonal dual-concentric-core photonic crystal fiber (PCF) is calculated with the finite element method (FEM) and proposed for broadband compensation. In order to realize highly negative dispersion, the hole diame

Self-pulsation effects of cladding-pumped Erbium-Ytterbium co-doped fiber laser (EYDFL) at around the lasing threshold are investigated. It is demonstrated that laser output of the Erbium-Ytterbium co-doped fiber under the bi-dire

Packaging of Distributed feedback (DFB) laser array based on reconstruction-equivalent-chirp (REC) technology is a bridge from chip to system, and influences the practical process of REC chip. In this letter, DFB laser arrays of 4

Light chirp is a major issue in optical fiber links. This letter deals with precise characterizations of the frequency chirp parameters of reflective semiconductor optical amplifiers (RSOAs). The RSOA chirp properties are represen

Infrared thermography determines the surface temperature of an object or human body. It is a promising imaging technology for medical and biological observations due to its contactless and completely noninvasive properties. Howeve

In this letter, a new single three-dimensional (3D) laser projector is proposed. As liquid crystal (LC) can produce two image patterns with orthogonal polarization states at 120 Hz, only one projector is required in this approach

A novel laser-electro magnetic acoustic transducer (EMAT) system for nondestructive testing NDT surface crack of continuous casting billet (CCB) is provided. Rayleigh wave generated by line laser source is used to detect the surfa

A tunable pulsed laser induced photoacoustic (PA) measurement set-up is established in the forward mode to monitor in vitro glucose concentration. A series of experiments are investigated to verify the feasibility of this set-up a

In order to couple into or out of a silicon photonic waveguide on silicon on insulator (SOI) substrate from optical fibers, we present a simple but practical method to design a grating coupler. The grating is periodic with fully e

Using the first-principles plane-wave pseudopotential method, based on the density function theory, the electron structure and optical properties of GaAs (100) \beta 2(2 \times 4) and GaAs (100) (4 \times 2) reconstructions are ca

A ring-cavity synchronously-pumped optical parametric oscillator (OPO) is investigated based on periodically poled KTi:OPO4 (PPKTP). The wavelength of the signal wave covers from 1 000 to 1 500 nm, the output power is 32.3 mW, and

Dynamics of two-component vector dark solitons are investigated by the variational approach in the defocusing nonlinear media, and effects of the weak nonlocality on the soliton propagation and interaction are analyzed. The nonloc

The thin mirrors are widely used in active optical system. In this letter, magnetic medium assistant polishing (MMAP) technology and device are discussed for thin mirrors optical finishing. The principle of MMAP is introduced, the

Toroidal surface and biconic surface are employed increasingly, however their profile cannot be null tested easily for they are non-rotationally symmetrical. Null testing method with cylinder compensator is proposed to solve this

A structure which consists of photoresist film sandwiched by Ag nano-particle and metal film is proposed to modify localized hotspot both in transversal and longitudinal direction. It shows that there is strong plasmonic coupling

We present high power terahertz quantum laser at about 3 THz based on bound-to-continuum active region design. At 10 K, corrected by the collection efficiency, the maximum peak power of 137 mW is obtained in pulsed mode. What’s mo

Nonlinear correlation between attenuation and absorption due to the presence of scattering is the main reason for inaccurate spectroscopic quantitative investigations. The polarization subtraction methods are applied to reduce the

We develop a phenomenological model to investigate dynamics of ionization-induced injection. In the "bubble" regime of laser wakefield acceleration (LWFA), it is found that there is an upper limit for laser intensity of ionization

A closed-form bit-error rate (BER) expression is derived for free-space optical (FSO) communication systems with circle polarization shift keying and spatial diversity receivers in the gamma-gamma (GG) distribution fading channel.

In the letter the polarization properties of quasi-homogenous (QH) beam propagating in Kolmogorov and non-Kolmogorov turbulence are studied. The results show that the polarization properties of QH beam undergoes three stages durin