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.

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.

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 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.

The invention relates to a method for producing waveguides (201) from a material (202) of the KTP family comprising the following method steps: b) treating the material (202) in such a way that a periodic poling of the material (202) is achieved, c), treating the material (202) in a molten salt bath (309c), which contains rubidium ions, characterized in that the molten salt bath (309c) which contains rubidium ions in step c) satisfies the following boundary conditions: the mole fraction of rubidium nitrate (RbNO.sub.3) in the melt lies in the range of 86-90 mol % at the beginning of the treatment, the mole fraction of potassium nitrate (KNO.sub.3) in the melt lies in the range of 10-12 mol % at the beginning of the treatment, the mole fraction of barium nitrate (Ba(NO.sub.3).sub.2) in the melt lies in the range of 0.5-1 mol % at the beginning of the treatment, the temperature of the melt lies in the range of 357363 C. during the treatment.

Thus the problem is solved, when reversing the known method steps, of achieving substantially identical diffusion depths of the ions during the ion exchange in order to produce periodically poled waveguides as free of corrugation as possible.

A wavelength conversion optical device includes: a substrate having a virtual plane and first and second regions and including multiple first crystal regions and multiple second crystal regions. Each of the multiple first crystal regions includes a pair of portions arranged in a direction intersecting a first plane with the first plane interposed therebetween, the first plane being located in the first region, and directions of spontaneous polarizations of each of the pair of portions being directions away from the first plane. Each of the multiple second crystal regions includes a pair of portions arranged in a direction intersecting a second plane with the second plane interposed therebetween, the second plane being located in the second region. Directions of spontaneous polarizations of each of the pair of portions being directions away from the second plane.

An electro-optic device may include a Mach-Zehnder modulator (MZM) and one or more components. The one or more components may apply a DC bias with dither to a first branch and a second branch of the MZM and to arms of the first branch, and may determine a second harmonic of a first return signal. The one or more components may apply a DC bias with phase-shifted dither to the first branch and the second branch or to the arms of the first branch, and determine a second harmonic of a second return signal. The phase-shifted dither may be out of phase from the dither and have a frequency that matches a frequency of the dither. The one or more components may determine whether arms of the second branch of the MZM are operating at null, and may selectively adjust DC biases applied to the arms of the second branch.

A system for frequency conversion, comprises a laser source and a harmonic generation crystal. The laser source is configured to produce optical pulse energy of less than 100 J. The harmonic generation crystal comprises a structure characterized by a nonlinear susceptibility, and a crystal grating period which adiabatically varies along the longitudinal direction in a manner that the crystal grating period is inversely proportional to a crystal grating function of a coordinate z measured along the longitudinal direction.

An optical wavelength conversion module including a substrate, a driving device, and a first phosphor material layer is provided. The first phosphor material layer is disposed on a first optical region of the substrate. A conversion beam generated by the first phosphor material layer is a yellowish green beam when a phosphor temperature of the first phosphor material layer is close to or equal to an ambient temperature. The conversion beam generated by the first phosphor material layer is a yellow beam when the phosphor temperature of the first phosphor material layer is close to or exceeds a preset temperature. The driving device is connected to the substrate. The driving device is adapted to drive the substrate to act when the optical wavelength conversion module is in an operating state, so that the yellow beam is emitted from the first optical region. An illumination module is also provided.

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.