A device for shifting a nonlinear crystal arranged to frequency convert a laser beam includes an anchor, a mount for holding the nonlinear crystal, and two parallel flexures each interconnecting the mount and the anchor to cantilever the mount from the anchor. Each flexure extends in a first horizontal direction from the mount to the anchor. The two flexures being offset from each other in a vertical direction. The device also includes a transducer connecting between the anchor and the mount. Bending of the transducer shifts the position of the mount in the vertical direction, and the two parallel flexures cooperate to prevent rotation of the mount during shifting of the mount position induced by the transducer. This device provides an inexpensive and compact crystal-shifter solution with crystal-orientation stability equaling that of far more costly and bulky conventional translation stages.

The invention relates to a frequency conversion arrangement (100) for optimising properties of a harmonic of a laser, in particular a beam profile and/or a long-term stability, the arrangement comprising:—a first non-linear crystal (X1), which is designed to convert a first wavelength (λ1) partially into a second wavelength (λ2); and—an optical unit, which in particular comprises at least one prism (P), which is designed in such a way as to influence the main axes (x1, y1, x2, y2) of the beam profiles of the first wavelength (λ1) and/or the second wavelength (λ2) differently; and—a second non-linear crystal (X2), which is designed in such a way as to generate a third wavelength (λ3) from the unconverted part of the first wavelength (λ1) and/or the second wavelength (λ2), the second non-linear crystal (X2) having an entry face (A1) and an exit face (A2), and the exit face (A2) running obliquely to the entry face (A1).

A display device including a display panel, in which a display region including a plurality of organic light emitting devices and a non-display region adjacent to the display region are defined, a protection film disposed below the display panel, a first adhesive layer contacting a bottom surface of the protection film, a supporting layer comprising a metallic material, at least overlapping the entire display region, and contacting the first adhesive layer, an input-sensing unit disposed on the display panel, an anti-reflection unit disposed on the input-sensing unit, and a window panel disposed on the input-sensing unit.

Bright entangled photon sources including an alignment-free, fiber-based, mechanically-rugged and generic interferometric module are disclosed. The inherent phase-stability of a Sagnac interferometer is deployed. High down-conversion efficiency of periodically poled nonlinear-waveguides is combined with the optical gain of semiconductor optical amplifiers and immunity of fiber optics. A single compact interferometric engine combines these attributes, allowing highly stable, integrable and bright polarization entangled-photon sources operating at room temperature. Using a minimum number of in-line optical parts, the compact module is based on a novel method that enhances the long-term stability and efficiency without compromising the entanglement quality. Besides energy entanglement, polarization entanglement is presented and set through the operational conditions. An optional periodically poled nonlinear waveguide can be hosted to achieve the desired spectral bandwidth and photons generation rate. The result is a zero-maintenance, lightweight, low-power consumption engine of compact and fully-integrable bright polarization-entangled photon sources.

A wavelength conversion device includes a nonlinear optical medium and a controller. The nonlinear optical medium configured to generate light from signal light and excitation light, the excitation light having a wavelength different from a wavelength of the signal light and having a second electric field strength than a first electric field strength of the signal light, the light having a wavelength different from a wavelengths of the signal light and the excitation light. The controller configured to control a first temperature of the nonlinear optical medium based on an intensity of the light.

Diffractive optical structures, lenses, waveplates, devices, systems and methods, which have the same effect on light regardless of temperature within an operating temperature range. Temperature-compensated switchable diffractive waveplate systems, in which the diffraction efficiency can be maximized for the operating wavelength and temperature by means of adjustment of the electric potential across the liquid crystal or other anisotropic material in the diffracting state of the diffractive state, based on prior measurements of diffraction efficiency as a function of wavelength and temperature. The switchable diffractive waveplates can be a switchable diffractive waveplate diffuser, a switchable cycloidal diffractive waveplate, and a switchable diffractive waveplate lens. An electronic controller can apply an electric potential to the switchable diffractive waveplate. Amplitudes of the electric potential can be determined from lookup tables such that diffraction efficiency at an operating wavelength and measured temperature is maximized. A communications channel can transfer the measured temperature from temperature measurement means to the electronic controller.

A wavelength converter including: A. a crystal holder configured to hold a nonlinear crystal configured to convert a wavelength of a laser beam incident thereon and output the wavelength-converted laser beam; B. a first container configured to accommodate the crystal holder and include a light incident window so provided as to intersect an optical path of the laser beam incident on the nonlinear crystal and a light exiting window so provided as to intersect the optical path of the laser beam having exited out of the nonlinear crystal; C. a second container configured to accommodate the first container; D. a position adjusting mechanism configured to adjust at least a position of the first container; and E. an isolation mechanism configured to spatially isolate the light incident window and the light exiting window from the position adjusting mechanism.

A heatable element is configured to apply sufficient energy density to contaminants in an internal ambient atmosphere with in a sealable housing to drive a reaction that inactivates the contaminants.

A nonlinear crystal comprising a first end face and an opposing second end face is described. The first and second end faces are separated along an optical axis of the nonlinear crystal by a length in the range of 0.25 mm and 2 mm. Although the length of the nonlinear crystal results in a reduction in the nonlinear effects induced on an optical field propagating through the crystal it also provides for reduced deviation experienced by the generated optical field when the nonlinear crystal is rotated. Therefore, when the nonlinear crystals are incorporated within an enhancement cavity their reduced length allows for the deviation of the output field to be minimised by servo control electronics arranged to adjust a single cavity mirror. This significantly reduces the complexity, and thus expensive of the servo control electronics when compared to those employed with the prior art enhancement cavities.

Disclosed are methods and apparatus for hermetically sealing a nonlinear optical (NLO) crystal for use in a laser system. A mounted NLO crystal, an enclosure base, a lid, and a plurality of window components are moved into an oven. A vacuum bake process is then performed on the mounted NLO crystal, enclosure base, lid, and plurality of window components until a humidity level that is less than a predefined amount is reached. The mounted NLO crystal, enclosure base, lid, and plurality of window components are moved from the oven onto a stage of a glove box that includes a sealing tool. In the glove box, the mounted NLO crystal is hermetically sealed into the enclosure base by sealing the lid and plurality of window components into openings of the enclosure base.