Super-resolution three-dimensional (3D) optical microscopy has incomparable advantages over other high-resolution microscopic technologies, such as electron and atomic force microscopy, in the study of biological molecules, pathways events live cells tissues. We present a novel approach structured illumination (SIM) by using digital micromirror device (DMD) for fringe projection low-coherence LED light illumination. The lateral resolution 90 nm sectioning depth 120 μm were achieved. maximum...

The imaginary Poynting momentum (IPM) of light has been captivated as an unusual origin optical forces. However, the IPM force is predicted only for dipolar magnetoelectric particles that are hardly used in manipulation experiments. Here, we report a whole family high-order forces not but also generic Mie particles, assisted with their excited higher multipoles within. Such optomechanical manifestations derive from nonlocal contribution to force, which can be remarkable even when incident...

Optical forces and torques offer the route towards full degree-of-freedom manipulation of matter. Exploiting structured light has led to discovery gradient curl forces, nontrivial optomechanical manifestations, such as negative lateral optical forces. Here, we uncover existence two fundamental torque components, which originate from reactive helicity momentum light, represent rotational analogues respectively. Based on introduce demonstrate concept torques, act transversely spin...

A radially polarized beam focused by a high-numerical-aperture (NA) objective has strong longitudinal and nonpropagating electric field in the focal region, which implies that it is suitable for axial optical trapping. In this paper, we use vectorial diffraction integral to represent distribution of high-NA then employ $T$-matrix method compute radiation forces on spherical particles. Effects different parameters, such as size sphere, inner radius beam, NA objective, are presented.

Light beams may carry optical spin or orbital angular momentum, both. The and parts manifest themselves by the ellipticity of state polarization vortex structure phase light beams, separately. Optical orbit interaction, arising from interaction between spatial has attracted enormous interest recently. spin-to-orbital momentum conversion under strong focusing is well known, while converse process, orbital-to-spin conversion, not been reported so far. In this paper, we predict in theory that...

By analyzing the vectorial Helmholtz equation within thin-layer approach, we find that light acquires a novel geometrical phase, in addition to usual one (the optical Berry phase), during propagation along curved path. Unlike phase is induced by transverse spin binormal direction and associated with curvature of curve. Furthermore, show Hall effect torsion curve direction, which different from light. Finally, demonstrate phenomena are described geometry-induced U(1) gauge fields adiabatic...

A Bessel beam has the properties of propagation invariance and a self-healing effect, leading to variety interesting phenomena applications. Recently, as planar diffractive element with miniaturized size, metasurfaces are widely employed manipulate light in subwavelength region, including generating beam. However, such metasurface-generated allows output no tunable functions. Here, interplay geometric phase dynamic phase, we propose method generate allow conversion from any orthogonal...

Photonics is currently undergoing an era of miniaturization thanks in part to two-dimensional (2D) optical metasurfaces. Their ability sculpt and redirect momentum can give rise force, which acts orthogonally the direction light propagation. Powered by a single unfocused beam, these lateral forces (LOFs) be used drive advanced metavehicles are controlled via incident beam's polarization. However, full control metavehicle on 2D plane (i.e. forward, backward, left, right) with sign-switchable...

The concept of lateral optical force (LOF) is general interest in manipulation as it releases the constraint intensity gradient tightly focused light, yet such a normally limited to exotic materials and/or complex light fields. Here, we report and controllable LOF nonchiral elongated nanoparticle illuminated by an obliquely incident plane wave. Through computational analysis, reveal that sign magnitude can be tuned multiple parameters particle (aspect ratio, material) (incident angle,...

Abstract The Belinfante spin momentum (BSM) is a fundamental yet enigmatic quantity of electromagnetic fields. It vanishes from the global field, but can be detected locally, manifesting itself as an optical force on small particles. Hitherto, however, BSM concept well established only within dipole approximation, and there no explicit experimental evidence for its action multipoles. Here, theoretical model multipolar forces, exerted generic Mie particles supporting multipoles arbitrary...

Azimuthally polarized beams, focused by a high-numerical-aperture (NA) objective lens, form hollow intensity distribution near the focus, which is appropriate for trapping low-refractive-index particles, in contrast to common linearly or radially beams. In this paper, field of azimuthally beam high-NA described vectorial diffraction integral, and then radiation forces on spherical particles with different parameters such as radius refractive index are calculated T-matrix method. Numerical...

An auto-focusing method for digital holographic microscopy has been proposed by employing two off-axis illumination beams. When specimens are illuminated plane waves in different directions, it is found that the farther reconstruction from image plane, wider reconstructed images separated each other. Thus, can be determinated finding minimum of variation between object on both amplitude and phase distributions. The feasibility demonstrated corresponding simulation experiment.

Low-refractive-index microparticles, such as hollow microspheres, have shown great significance in some applications, biomedical sensing and targeted drug delivery. However, optical trapping manipulation of low-refractive-index microparticles are challenging, owing to the repelling force exerted by typical traps. In this paper, we demonstrated rotating large-sized using quasi-perfect vortex (quasi-POV) beams, which were generated Fourier transform high-order quasi-Bessel beams. Numerical...

Transverse spin angular momentum, which appears locally in the structured optical fields, has attracted much attention, owing to its extraordinary properties and potential applications. We show theoretically that, by highly focusing a vector vortex beam with azimuthally varied polarization, it is possible trap multiple particles simultaneously manipulate particles' along azimuthal direction. Both direction magnitude of so torque on particle, can be changing state input beams. Moreover,...

Focusing fields of optical vortex (OV) beams with circular or radial polarizations carry both spin angular momentum (SAM) and orbital (OAM), can realize non-axial spinning orbiting motion absorptive particles. Using the T-matrix method, we evaluate forces torques exerted on micro-sized particles induced by OV beams. Numerical results demonstrate that particle is trapped circle intensity maxima, experiences a transverse torque along azimuthal direction, longitudinal torque, an respectively....

The perfect optical vortex (POV), the ring size being independent of its topological charge, has found potential applications in tweezers and communications. In this Letter, we report a new kind POV, termed as double-ring POV (DR-POV), whose diameters two rings are charge. We theoretically demonstrate that such is Fourier transform an azimuthally polarized Bessel beam. Experimental results agree well with theoretical prediction. further investigate nature DR-POV through interferometric...

Super-resolution structured illumination microscopy (SIM) routinely performs image reconstruction in the frequency domain using an approach termed frequency-domain (FDR). Due to multiple Fourier transforms between spatial and domains, SIM suffers from low speed, constraining its applications real-time, dynamic imaging. To overcome this limitation, we developed a new method for reconstruction, (SDR). SDR is intrinsically simpler than FDR, does not require theory predicts it be rapid method....

Abstract Enantiomers (opposite chiral molecules) usually exhibit different effects when interacting with agents, thus the identification and separation of enantiomers are importance in pharmaceuticals agrochemicals. Here an optical approach is proposed to enantioselective trapping multiple pairs by a focused hybrid polarized beam. Numerical results indicate that such beam shows local chirality opposite signs focal plane, can trap corresponding near extreme value density according handedness...

We propose dual-wavelength digital holographic microscopy with a slightly off-axis configuration. The axial measurement range without phase ambiguity is extended to the micrometer by synthesizing beat wavelength between two wavelengths separation of 157 nm. Real-time specimen made possible virtue high selectivity Bayer mosaic filtered color CCD camera. principle method exposed, and practicability proposed configuration demonstrated experimental results on vortex plate rectangular step.

An autofocusing method for two-wavelength digital holographic microscopy (TWDHM) based on the wavelength dependence of diffraction process is proposed. Red and green lights are employed illumination TWDHM, generated holograms recorded simultaneously by a color CCD camera. Due to dependency process, farther reconstruction plane from image plane, larger difference between red light distributions. Thus, can be determined finding minimum variation their amplitude The feasibility proposed...

Abstract In merits of super-resolved resolution and fast speed three-dimensional (3D) optical sectioning capability, structured illumination microscopy (SIM) has found variety applications in biomedical imaging. So far, most SIM systems use monochrome CCD or CMOS cameras to acquire images discard the natural color information specimens. Although multicolor integration scheme are employed, multiple excitation sources detectors required spectral is limited a few wavelengths. Here, we report...

Holographic optical tweezers are a powerful trapping and manipulation tool in numerous applications such as life science colloidal physics. However, imperfections the spatial light modulator components of system will introduce detrimental aberrations to system, thereby degrading performance significantly. To address this issue, we develop an aberration correction technique by using high-order vortex metric. The optimal Zernike polynomial coefficients for quantifying determined comparing...

A wide-field fluorescence microscope with a double-helix point spread function (PSF) is constructed to obtain the specimen's three-dimensional distribution single snapshot. Spiral-phase-based computer-generated holograms (CGHs) are adopted make depth-of-field of adjustable. The impact system aberrations on PSF at high numerical aperture analyzed reveal necessity aberration correction. modified cepstrum-based reconstruction scheme promoted in accordance properties new PSF. extended images and...

Benefitting from the development of commercial spatial light modulator (SLM), holographic optical tweezers (HOT) have emerged as a powerful tool for life science, material science and particle physics. The calculation computer-generated holograms (CGH) generating multi-focus arrays plays key role in HOT trapping bunch particles parallel. To realize dynamic 3D manipulation, we propose new tilted-plane GS algorithm fast generation multiple foci. multi-focal spots with uniformity 99% can be...