A highly-efficient ridge waveguide includes a base substrate of a single-crystal and a core substrate made of a nonlinear optical medium, the base substrate and the core substrate being directly bonded, and includes a thin film layer formed on a surface of the core substrate on the upper side of a periodically polarization-reversed structure, and becomes a wavelength conversion element. A direct bonding method through thermal diffusion is applied to bonding. The core substrate has a ridge structure formed in a light propagating direction and a reversed structure formed by processing this. A surface of the core substrate is ground and a thin film layer is formed on the ground surface. A core formed by digging a core layer of the core substrate in an unbonded state is provided on an upper surface of an undercladding layer of the base substrate in a bonded state. Two side surfaces of the core are in contact with an air layer.

Provided are a wavelength converting particle, a method for manufacturing a wavelength converting particle, and a light-emitting diode containing a wavelength converting particle. The wavelength converting particle comprises a hybrid OIP nanocrystal that converts a wavelength of light generated by an excitation light source into a specified wavelength. Accordingly, it is possible to optically stabilize and improve color purity and light-emission performance without changes in a light-emitting wavelength range.

A wavelength conversion device includes a second-order nonlinear optical medium with a polarization inversion structure, wherein the wavelength conversion device performs wavelength conversion between three wavelengths according to a relationship of 1/λ.sub.1=1/λ.sub.2+1/λ.sub.3, a polarization inversion period Λ of the polarization inversion structure is divided into 2a regions, and when the 2a regions divided from the polarization inversion period Λ each has a width ratio of an inverted region and a non-inverted region of r to 1−r (where 0≤r≤1), a ratio value r is set such that, when one period in phase of a sine function from 0 to 2π is divided into 2a regions, a value of the sine function in a center of each divided region is (1−2r)±0.1.

Provided are a wavelength converting particle, a method for manufacturing a wavelength converting particle, and a light-emitting diode containing a wavelength converting particle. The wavelength converting particle comprises a hybrid OIP nanocrystal that converts a wavelength of light generated by an excitation light source into a specified wavelength. Accordingly, it is possible to optically stabilize and improve color purity and light-emission performance without changes in a light-emitting wavelength range.

An exemplary system can be provided which can include, for example, a plurality of source arrangements configured to provide a plurality of electro-magnetic radiations to at least one of at least one sample or at least one reference structure, a first arrangement configured to receive a first radiation(s) from the reference structure(s), a second arrangement configured to receive a second radiation(s) from the sample(s), where a portion(s) of the second radiation(s) can be in an invisible spectrum, a third arrangement configured to combine the first radiation(s) and the second radiation(s) into a third radiation(s), and a fourth arrangement configured to convert the third radiation(s) into a further radiation in a visible spectrum based on the at least one portion.

A wavelength converter stabilizes output light intensity in which the light coupling efficiency to a light waveguide core is not easily varied. A mounting structure is adopted in which a substrate of a wavelength conversion element is a material with a lower refractive index for signal light than that of the core, and a support structure that suppresses elastic deformation by supporting the element through a contact at a tip end surface at a position corresponding to both end portions of the core at the occurrence of elastic deformation due to the thermal stress of the element is provided. The support structure is provided at a portion apart from a temperature control element at the top surface of a metal housing bottom surface member, and its top surface is disposed in the vicinity of a portion corresponding to both end portions of the core of the element in a support member.

Provided are a wavelength converting particle, a method for manufacturing a wavelength converting particle, and a light-emitting diode containing a wavelength converting particle. The wavelength converting particle comprises a hybrid OIP nanocrystal that converts a wavelength of light generated by an excitation light source into a specified wavelength. Accordingly, it is possible to optically stabilize and improve color purity and light-emission performance without changes in a light-emitting wavelength range.

An optical component includes an optical device comprising a bonding face and an optically polished end face, and a metal film formed on the bonding face of the optical device and for bonding the optical device onto a substrate. The metal film includes a main covering portion covering a region except an end part of the bonding face on the side of the end face and an end part-covering portion covering the bonding face in the end part. A non-covered part, which is not covered by the metal film, is provided between the main covering portion and end part-covering portion.

A photonic chip for optical frequency conversion includes a substrate, and a planar optical waveguide disposed along a surface of the substrate. The optical waveguide has an optical core of periodically-poled thin-film ferroelectric material, the thickness of the optical core varying along the optical waveguide. The width of the optical core varies therealong in a manner correlated with variations of the thickness of the optical core along the optical waveguide, e.g. in a manner complementary to measured variations of the thickness.

The disclosed laser system is configured with a laser source outputting light at a fundamental frequency. The output light is incident on a frequency converter operative to convert the fundamental frequency to a higher harmonic including at least one frequency converting stage. The frequency converter is based on a SrB.sub.4O.sub.7 (SBO) or PbB.sub.4O.sub.7 (PBO) nonlinear crystal configured with a plurality of domains. The domains have periodically alternating polarity of the crystal axis enabling a QPM use and formed with each with highly parallel walls which deviate from one another less than 1 micron over a 10 mm distance.