Ceramoptec Industries, Inc.

Sergej G Krivoshlykov

Wolfgang Neuberger

Vladimir Alexandrovich Sychugov

Nikolai Mikhailovich Lyndin

Pavel F Oleksenko

Alexander M Kamuz

The invention describes a method of single-transverse-mode generation for waveguide lasers of various kinds having a large cross section of their active core and thus providing a possibility of efficient pump of the active core region. This results in a laser beam with enhanced power and high spatial quality for high efficiency coupling to standard single-mode optical fiber networks. It is found that a multimode waveguide having a central dip of special shape in the refractive index profile of its core is able to guide a higher order mode with sharp central peak of its field carrying the considerable part on the mode energy and whose width is well compatible with the width of the fundamental mode of standard single-mode fibers. The useful properties of this higher order mode can be employed to provide the single-transverse-mode regime of generation in optical fiber lasers, integrated optical micro-lasers and various semiconductor laser sources.

Optical fiber and integrated optic lasers with enhanced output power

An optical spectrum analyzer based on optical processing of the far field interference pattern from two beams irradiated by light transmitting waveguides is described. The spectrum analyzer can operate in UV, VIS, NIR and MIR ranges of spectrum and it can be based on either optical fibers (multimode or single-mode) or integrated optical waveguides. It has many important applications, for example, as a simple, compact and inexpensive spectrum analyzer used with fiber optic chemical and biological sensors.

Compact, all-optical spectrum analyzer for chemical and biological fiber

The invention describes two types of multimode optical waveguides having special dip in the refractive index profile of their core providing conditions for propagation of a higher order mode with sharp central peak which field carries considerable part of the mode energy, while the fields of all other modes in the waveguide are mostly concentrated outside of this central peak region. The waveguide of the first type guides the mode only with one central peak while the mode in the waveguide of the second type has also an additional peak at the interface between the waveguide core and cladding providing a possibility to detect any influence on the mode field in its outer region by measuring the signal in the central peak of the mode. The useful properties of these two kinds of modes can be employed for designing new wavelength selective waveguide components for optical communications and sensors applications: an optical waveguide modulator, amplitude and interferometric sensors for different applications, bistable nonlinear components for logic switching and optical memory, wavelength selective chemical sensors of both amplitude and interferometric type, etc. Employing a material exhibiting electro-optical properties provides a possibility of tuning of the components proposed as well as fabrication of the sensors of electric fields.

Multimode optical waveguides, waveguide components and sensors

Linearly distributed illumination systems based on flexible optical waveguides or optical fibers are described for both high brightness and low brightness applications. Light illumination at preselected locations is accomplished by transferring light from the light carrying core region to the outer layers of the waveguide/fiber structure. A curled waveguide, typically having a rectangular band-like core cross section and cut at an angle facing the light source, serves to optically couple light with simplicity and high efficiency into the waveguide for high brightness applications. Grooves into sides of the band waveguide, in either the small or large dimension, provide a means for removing light from the core to illuminate preselected regions along the length of the band waveguide. Complex systems comprising a bundle of band waveguides and an optical feedback means for automatic control of illumination brightness are also described. For low brightness applications an illuminating system comprising a flexible band covered with a fluorescent material in sites along the length of the waveguide where illumination is required for a specific application.

Flexible system for linearly distributed illumination

A compound laser system for generating beams of high brightness and high power density by constructive phase coherent combination of the beams generated by a number of individual sources of coherent radiation three subsystems: a diode laser subsystem which is the source of power for the system; a combiner subsystem which combines the output of the diode lasers; and, an optional delivery subsystem which may be needed to deliver the combined output to its desired destination for industrial or medical applications. The combiner subsystem may be implemented in its entirety as an Integrated Optical Combiner, a single component performing all the combiner subsystem's functions. A preferred embodiments of the combine subsystem employs optical fibers having shaped cores to provide efficient matching to the geometry of typical laser diodes. Each diode laser's output of a diode laser array is captured by a single optical fiber with a core whose cross-sectional shape is contoured so that major and minor axes of a laser diode's output shape are not larger than major and minor axes of a optical waveguide and whose numerical apertures are closely matched to the numerical apertures in the directions of corresponding axes. The waveguides are combined in a combiner subsystem into a single output source whose cross-sectional shape depends on the number and cross-sectional shape if the input ports. A delivery subsystem takes output from the combiner subsystem using a standard round or contoured optical fiber core, depending on the cross-section shape of the combiner subsystem's output.

Compound laser system for high power densities

A new family of lasers and optical parametric oscillators is based on efficient frequency conversion or doubling in multimode compound optical waveguides. These waveguides exploit specific useful properties of their higher order modes while providing good compatibility with single-mode optical fibers. A mode engineering approach is applied to construct a compound waveguide structure that supports a higher order mode having a sharp peak in its field. This sharp peak simplifies selection of this mode by efficient coupling of its radiation into a single-mode fiber. The lasers and optical parametric oscillators employ wavelength selective properties of this mode field configuration and its unique ability to support efficient frequency conversion and doubling.

Compound waveguide lasers and optical parametric oscillators

A flexible fiber optic delivery system for medical and industrial applications is described that can transmit high laser power densities and optical images. A parabolic-index profile of a graded-index fiber is perturbed so as to prevent strong localization of a laser beam in the fiber's recurring focal regions. This permits transmission of high laser powers without danger of fiber damage. An additional gain in carrying capacity for the system is achieved by using a wavefront perturbation system between the laser source and the graded-index fiber. Optical image transmission is achieved by using a measured perturbation to a parabolic-index profile of the graded-index fiber with a prescribed length and a wavefront reconstruction system in combination with the wavefront perturbation system. The system has an increased laser induced damage threshold and can transmit highly focused optical images.

Power laser delivery fiber system with enhanced damage threshold

A multichannel connector for transmission of optical signals between a number of input and output channels through a rotating interface is described. The connector comprises an input and an output platforms rotating around their common axis and an optical system connecting input optical signal channels to output optical channels independent on relative rotation of the platforms. The connector conserves both the amplitude and phase of the optical signals transmitted between the input and output channels. The optical system comprises either a combination of lenses and prism rings or single computer generated hologram. It can be used, for example, for connection between input and output bundles of optical fibers through a rotation interface without cross talk of the optical signals. The connector can find important industrial, military and medical applications where the optical signals from a number of channels are to be transmitted through rotating junctions.

Connector for multichannel transmission of optical signals through

The present invention is directed at an all-fiber in line isolator. The basic isolator includes a monomode optical fiber, a multimode waveguide, a coil or other traditional means to generate a magnetic field, and a fiber block or other traditional means to couple the fiber to the waveguide. In one embodiment, the fiber has a core and a cladding, and maintains a circular state of light polarization. The fiber has a coupling region where the cladding is partially removed. The waveguide evanescently couples to the fiber along the coupling region. The waveguide has magneto-optical properties such that applying a magnetic field along it causes backward propagating light to transfer to the waveguide with minimal disturbance to forward propagating light. Other embodiments using birefringent optical fibers are disclosed as well.

Growing community of inventors

Moscow, Russia

Sergej G Krivoshlykov