We propose a sub-aperture stitching algorithm based on a frequency domain that can be denoted as a power spectral density (PSD). Our algorithm is verified by the experimental data obtained from measuring a Φ1.23 m mirror at the Ch

We report a 1.8 μm two-section distributed Bragg reflector laser using butt-jointed InGaAsP bulk material as the waveguide core layer. The threshold current is 17 mA and the output power is 8 mW on average. The threshold current,

A surprising phenomenon can be discovered by using femtosecond double-pulse ablation of silicon and germanium in ethanol. The ablation areas present an oscillation increase phenomenon when the pulse delay increases from 200 fs to

A ring of three unidirectionally coupled semiconductor lasers (RTUC-SLs) is used to generate broadband chaos with no pronounced time-delay (TD) signature. Using the autocorrelation function and permutation entropy as the TD measur

A stable three-channel dual-wavelength fiber ring laser is proposed and experimentally demonstrated. The digital micromirror-device (DMD) processor can select and recirculate any dual waveband from the gain spectrum of the erbium-

A simple and repeatable method to fabricate high-aspect-ratio (HAR) and high-quality microgrooves in silica is reported. The method consists of two steps: (1) formation of laser-modified regions by femtosecond Bessel beam irradiat

The generation and measurement of complex ultraviolet laser pulse shapes is demonstrated in the SG-III laser facility. Relatively high contrast ratio of 300∶1 required by the physics experiment is achieved and successfully measure

The combination of deep wet etching and a magneto-rheological finishing (MRF) process is investigated to simultaneously improve laser damage resistance of a fused-silica surface at 355 nm. The subsequently deposited SiO2 coatings

Two kinds of novel blue-emitting materials, anthracene-based derivatives, are synthesized by the Suzuki coupling reaction. It is worth noting that the maximum emission wavelengths of the two materials are 441 and 444 nm in tetrahy

The bit error rate performance of non-line-of-sight ultraviolet communication through atmospheric turbulence is studied. The communication performance degradation under different strengths of turbulence is evaluated. Particularly,

The stochastic parallel gradient descent (SPGD) algorithm is widely used in wavefront sensor-less adaptive optics (WSAO) systems. However, the convergence is relatively slow. Modal-based algorithms usually provide much faster conv

A surface defect evaluation system can combine microscopic scattering dark-field imaging with sub-aperture scanning and stitching. Thousands of sub-apertures are involved; mechanical errors will cause stitching dislocation, leadin

In this Letter, we present a possible methodology to directly “read” the force on an atom via the photons emitted from the atom. In this methodology, the mean radiative force on an atom exerted by external fields can be expressed

Refractive indices for crystals ammonium dihydrogen phosphate (ADP), 30% deuterated ADP (DADP), 50% DADP, and 70% DADP are measured from 253 to 1529 nm with 5×10 6 accuracy. Numerical fits to modified double-pole Sellmeier equatio

We report on the rich dynamics of two-dimensional fundamental solitons coupled and interacting on the top of an elliptical shaped potential in a two-dimensional Ginzburg–Landau model. Under the elliptical shaped potential, the sol

Adaptive optics (AO) systems greatly improve the resolution of retinal imaging instruments by actively correcting ocular aberrations. In this Letter, closed-loop correction as well as ocular aberration compensation of a 62-element

A transfer method is introduced to derive the normalized radiance for CE318 Sun/sky radiometer using viewing solid angles and extraterrestrial calibration constants. The new transfer method has a good consistency at different part

Nonlinear dynamics in an optoelectronic delayed feedback semiconductor laser and its application in sensing are studied. We analyze the theories of stability and period of the laser. A route to quasi-periodic bifurcation or a stoc

Signal distortion due to the non-uniform response of the detector degrades the measurement accuracy of most metrology instruments. In this Letter, we report a newly developed calibration source system for reference-based non-unifo

A static-mode synthetic aperture imaging ladar (SAIL) in which the target and carrying platform are kept still during the collection process is proposed and demonstrated. A target point of 0.5 mm×0.5 mm and a two-dimensional (2D)