Abstract: A second-harmonic generation nonlinear frequency converter includes a nonlinear optical crystal. The nonlinear optical crystal includes a plurality of sections. The sections connect to each other in sequence, and each section has a phase different from others. Each of the phases includes a positive domain and a negative domain. Each of the sections includes a plurality of quasi-phase-matching structures. The quasi-phase-matching structures connect to each other in sequence and have the same phase in one section.

Abstract: A second-harmonic generation nonlinear frequency converter includes a nonlinear optical crystal. The nonlinear optical crystal includes a plurality of sections. The sections connect to each other in sequence, and each section has a phase different from others. Each of the phases includes a positive domain and a negative domain. Each of the sections includes a plurality of quasi-phase-matching structures. The quasi-phase-matching structures connect to each other in sequence and have the same phase in one section.

Abstract: The present invention is in related to a miniature surface plasmon resonance waveguide device with sinusoidal curvature compensation and at least comprises: a substract, a waveguide structure, a sensing film layer and a cover layer, wherein the waveguide structure is configured with the function of sinusoidal curvature compensation and installed above the substract, further that, the waveguide structure includes a light input port and a light output port; the sensing film layer is on a special region of the waveguide structure, the special region is a sensing region; the cover layer is upper than the substract and has an opening. By means of the optimal curve figure of the sinusoidal curvature compensation, attenuation of light energy can be minimized while in propagation, and allows the input and output of the light on the same side of the device.

Abstract: An improved linear wave guide type surface plasmon resonance (SPR) microsensor, particularly a microsensor employing a dual-opening multi-channel design, adopts a cross differential comparison to enhance the performance of the microsensor and uses a surface plated metal thin film to provide a wavelength absorption according to a SPR characteristic and match with an appropriate sized micro-channel to give a highly sensitive high-flux measurement. The invention applied in a water solution sample comprises: a substrate; a bottom layer contacting a surface of the substrate; at least one wave guide layer contacting the bottom layer and the other surface of the substrate; at least two SPR sensing areas on a surface opposite to the contact surface of the wave guide layer and the bottom layer; at least two SPR sensing film layers on a surface opposite to the contact surface of the two PRS sensing areas and the wave guide layer.

Abstract: The present invention is in related to a miniature surface plasmon resonance waveguide device with sinusoidal curvature compensation and at least comprises: a substract, a waveguide structure, a sensing film layer and a cover layer, wherein the waveguide structure is configured with the function of sinusoidal curvature compensation and installed above the substract, further that, the waveguide structure includes a light input port and a light output port; the sensing film layer is on a special region of the waveguide structure, the special region is a sensing region; the cover layer is upper than the substract and has an opening. By means of the optimal curve figure of the sinusoidal curvature compensation, attenuation of light energy can be minimized while in propagation, and allows the input and output of the light on the same side of the device.

Abstract: The present invention relates to a method to control the nucleation and transverse motion of 180° inverted domains in ferroelectric nonlinear crystals. It includes a process composing of a high temperature oxidation of the first metal layer and a pulsed field poling of the second electrodes. The main object of present invention is to provide domain inversion of ferroelectric nonlinear crystals with field control the nucleation and transverse motion of inverted domains and two-dimension nonlinear photonic crystals for time-domain multiple-wave simultaneous lasers and space filter function. Another object of present invention is to provide space-charge effect for screened edge field beneath the metal electrode, The other object of present invention is to provide the constraint of inverted domain nucleation in the oxidized electrode for arbitrarily geometrical form of 2D ferroelectric lattice structure.

Abstract: The present invention relates to a method to control the nucleation and transverse motion of 180° inverted domains in ferroelectric nonlinear crystals. It includes a process composing of a high temperature oxidation of the first metal layer and a pulsed field poling of the second electrodes. The main object of present invention is to provide domain inversion of ferroelectric nonlinear crystals with field control the nucleation and transverse motion of inverted domains and two-dimension nonlinear photonic crystals for time-domain multiple-wave simultaneous lasers and space filter function. Another object of present invention is to provide space-charge effect for screened edge field beneath the metal electrode, The other object of present invention is to provide the constraint of inverted domain nucleation in the oxidized electrode for arbitrarily geometrical form of 2D ferroelectric lattice structure.

Abstract: A method is used to fabricate a wide-angle Y-branch polarization splitters on lithium niobate crystal substrate. The Y-branch polarization splitter combines a straight waveguide with a substrate prism type wide-angle waveguide branch. The straight waveguide is a random polarization nickel diffusion waveguide. The branching waveguide is a proton exchanged waveguide. The fabrication technology needs only once of nickel diffusion and once of proton exchange. Due to the inherent property of single polarization for the proton exchanged waveguide, only the extraordinary polarization wave is bent and the ordinary wave remains in the straight waveguide. This results in a polarization splitter with high extinction ratio.

Abstract: This is a fabrication process for Y-branch nickel/zinc-indiffused polarization splitters on lithium niobate. The fabrication technology needs only two nickel/zinc indiffusions; one at a high temperature and the other at a lower temperature. Nickel/zinc-indiffused waveguides can support single-ordinary, single-extraordinary, and random polarization waves depending on the fabrication process parameters. High extinction ratios can be achieved due to the inherent single-polarization of the waveguides. The splitting ratios of the TE and TM modes are sufficiently high for practical applications.

Abstract: We disclose a new optical TE-TM mode splitter on lithium niobate. The splitter is fabricated by using an asymmetric Y-junction structure which is composed of a straight waveguide, and two branch waveguides. The straight waveguide is the input one that can guide randomly-polarized light (i.e. both TE and TM modes). The two branch waveguides are the output ones, and one of them can guide only the TE mode, the other can guide only the TM mode. Because the output waveguides can individually guide the TE and TM modes, the input modes are then split by the branch waveguides. The input waveguide is fabricated by diffusing titanium into lithium niobate. The two output waveguides are made by nickel indiffusion and magnesium-oxide induced lithium outdiffusion or proton exchanged techniques.