Complex amplitude and polarization distribution of an optical beam plays a dominant role in shaping the focused structure of the beam. It is therefore possible to engineer the focal spot using the pupil function manipulation. Helical phase structure arising due to phase singularity in the wave front plays an important role in shaping the focal spot. Tight focusing of an optical beam produces in...

Palcewska et al. first demonstrated near infrared (NIR) visual response in human volunteers upon two-photon absorption (TPA), a seminal work of 2014, and assessed the process terms wavelength- power-dependence on murine ex-vivo retinas. In present study, electroretinography (ERG) is further developed to perform complete characterization effect NIR pulse duration, energy, focal spot size respons...

A new radial focusing device is described that condenses an incident laser beam to an extremely intense and uniformly illuminated focal spot. The focal region is useful for many applications. When used with a 10.6-microm CO(2) TEA laser source, a disk-shaped air-breakdown spark results, and the properties of this spark have been investigated.

Photonic integrated circuits (PICs) provide a promising platform for miniaturized on-chip optical systems communication, computation, and sensing applications. The dense integration of photonic components is one the keys to exploit advantages PIC. Although light focusing fundamental indispensable function in PICs, at micro/nanometer-scale challenging. Here, bigradient metalens (BOML) proposed a...

SUMMARY Numerical experiments of seismic wave propagation in a laterally homogeneous layered medium explore subsurface imaging at subwavelength distances for dense arrays. We choose time-reversal approach to simulate fundamental mode Rayleigh surface wavefields that are equivalent the cross-correlation results three-component ambient field records. demonstrate synthesized 2-D spatial autocorrel...