Abstract: Optical triplexers are disclosed. The optical triplexers include an optical fiber, a first ball lens optically coupling a first optical signal between a first opto-electronic device and a first wavelength selective filter, and a second ball lens optically coupling a second optical signal between a second opto-electronic device and the first wavelength selective filter. The optical triplexers further include a second wavelength selective filter optically coupling the first and second optical signals between the first wavelength selective filter and a third ball lens and a fourth ball lens optically coupling a third optical signal between a third optical signal between a third opto-electronic device and the second frequency selective filter. The second wavelength selective filter optical couples the third optical signal between the fourth ball lens and the third ball lens. Thus, each of the optical signals are selectively coupled between one of the opto-electronic devices and the optical fiber.

Abstract: The invention relates to wavelength-selective optical filters for allowing light of a narrow optical spectral band, centered around a wavelength (?c) to pass through them, while reflecting the wavelengths lying outside this band. According to the invention, the transfer function (T1,2(?)) of the component is defined by multiplying two transfer functions of spectrally offset Fabry-Perot filters.

Abstract: An optical conversion device for a shared FTTH distribution network including first and second optical fibers and an optical processing circuit. The optical processing circuit has an input for receiving a first optical analog signal carried by the first optical fiber and an output for providing a first optical digital signal for transmission via the second optical fiber. The optical processing circuit is configured to digitize the first optical analog signal and incorporate into the first optical digital signal. The optical analog signal may be an optical signal which is modulated by an RF signal, which is the same or similar to that of existing HFC networks. High loss electrical signals are converted to low-loss optical signals propagated within the optical plant. The combined optical analog and digital protocol supports analogous communications of existing HFC networks and the optical plant minimizes cost of fiber optic upgrade.

Abstract: A transmission characteristics evaluation system can measure the dispersion tolerance and the insertion loss gradient tolerance at a high precision with reduced number of working steps for the measurement in evaluating the transmission characteristics of an optical module. The transmission characteristics evaluation system comprises an optical transmitting apparatus, an optical receiving apparatus for, and a pseudo transmission path apparatus interposed between the optical transmitting apparatus and the optical receiving apparatus. The pseudo transmission path apparatus has, in a pseudo manner, transmission characteristics of a transmission path to which the optical transmitting apparatus and the optical receiving apparatus are to be connected. The pseudo transmission path apparatus comprises a transmission characteristics setting section for setting transmission characteristics equivalent to the transmission characteristics that the transmission path can have, by controlling a mirror or an optical element.

Abstract: An optical communication device having multiple light sources under a single lens. The optical communication device has two light sources. The optical communication device has a lens optically coupled to the two light sources. The lens is shaped to direct light from the two light sources towards an axis of the lens. The optical communication device further has a third light source located below the approximate center of the lens.

Abstract: A system for a re-configurable optical de-multiplexer, multiplexer or add/drop multiplexer is provided. A re-configurable de-multiplexer system comprises a wavelength selective switch having an input port, an output port and an internal port; a wavelength division de-multiplexer (WDM) optically coupled to the internal port and a plurality of dropped-channel ports optically coupled to the WDM. The wavelength selective switch receives a plurality of input wavelength-division multiplexed channels from the input port and routes a first subset of the channels to the output port and a second subset of channels to the internal port and then to the WDM. The WDM separates each of the dropped channels to a different respective one of the channel ports.

Abstract: An OADM includes optical input and output; first and second bandpass filters with a first pass band, optically coupled to the optical input and output, respectively; third and fourth bandpass filters with a second pass band, optically coupled to reflection ports of the first and second bandpass filters, respectively; first and second cascaded series of channel filter assemblies optically coupled to the transmission ports of the first and second bandpass filters, respectively, and third and fourth cascaded series of channel filter assemblies optically coupled to the transmission ports of the third and fourth bandpass filters, respectively. The OADM may be extended or upgraded so as to accommodate the throughput of additional channels or wavelengths by extending the number of filters within each cascaded series of bandpass filters, where the transmission ports of the additional bandpass filters are optically coupled to respective additional cascaded series of channel filter assemblies.

Abstract: This invention provides a system that combines a wavelength multiplexer with an FM discriminator for chirp reduction and wavelength locker in a filter to produce a wavelength division multiplexed signal with reduced chirp. A partially frequency modulation laser signal is converted into a substantially amplitude modulation laser signal. This conversion increases the extinction ratio of the input signal and further reduces the chirp. A wavelength division multiplexing (WDM) method is used for transmitting high capacity information through fiber optics systems where digital information is carried on separate wavelengths through the same fiber. Separate transmitters normally generate their respective signals that are transmitted at different wavelengths. These signals are then combined using a wavelength multiplexer to transmit the high capacity information through the fiber optic system.

Abstract: An optical communication system has a plastic optical fiber (POF) and an optical communication module. The POF has a spherical end surface, and light emitted from the spherical end surface has an NA of 0.35 or lower. The POF is installed in the module such that a light receiving surface of a light receiving element (PD) is at a distance, d, from an apex of the spherical end surface. The distance, d, is within a range of 0<d?r*D/(n?n1) when a PD diameter is not larger than D, and within a range of D?d?r*D/(n?n1) when the PD diameter is larger than D, where D is a diameter of the POF, r*D is a radius of curvature of the spherical end surface, n is a refractive index of a core of the POF, and n1 is a refractive index of a substance between the spherical end surface and the PD.

Abstract: A wavelength division element includes a first filter and a second filter. The first filter has incident angle-to-transmission wavelength characteristics and separates multiplexed lights in a plurality of wavelength bands into first lights that are in a first wavelength band and first reflected lights. The first filter allows the first lights to pass through in a first direction and reflects the first reflected lights in a second direction. The second filter is located in the second direction and separates the first reflected lights into second lights that are in a second wavelength band and second reflected lights. The second filter allows the second lights to pass through in a third direction and reflects the second reflected lights in a fourth direction.

Abstract: Optical systems are provided. A representative optical system includes an optical transceiver with an optical source and an optical receiver. The system also includes an optical waveguide. At least one of the optical source and the optical receiver is optically coupled to an intermediate portion of the optical waveguide. The optical source provides optical signals for propagation by the optical waveguide, and the optical receiver receives optical signals propagated by the optical waveguide. Methods, optical transceivers and other systems also are provided.

Abstract: The present invention relates to a diffractive grating member and to an optical communication module. The optical communication module includes a semiconductor laser; a coupling optical system for coupling a light flux with a wavelength of ?1 emitted by the semiconductor laser to an optical fiber; and two light-receiving elements for receiving at least two light fluxes each having wavelengths ?2 and ?3 emitted from an end surface of the optical fiber. The coupling optical system has a diffractive structure, and the coupling optical system changes paths of light fluxes each having wavelengths ?1, ?2 and ?3 into relatively different directions such that the light flux with the wavelength ?1 emitted by the semiconductor laser enters into the optical fiber and each of the at least two light fluxes each having the wavelengths ?2 and ?3 enters into each of the two light-receiving elements.

Abstract: The present invention describes a structure and method for a multi-ports WDM device for compensating the filter distortion while reducing insertion loss. The multi-ports WDM device comprises a 4-fiber collimator having a grin lens and a 2-fiber collimator having a lens where the focal plane of the second lens is shorter than the focal plane of the first grin lens Ands with aspheric surface. When a light signal travels through the first lens in the 4-fiber collimator to a filter, the film on the filter causes distortion to the light signal resulting in a large insertion loss. To compensate for the insertion loss, the lens on the 2-fiber collimator has a aspheric function and a shorter focal plane than the grin lens on the 4-fiber collimator. The type of grin lens used in the 4-fiber collimator is different than the lens used in the 2-fiber collimator. Effectively, the lens in the 2-fiber collimator operates to de-focus a light signal relative to the grin lens in the 4-fiber collimator.

Abstract: A novel wavelength routing apparatus is disclosed, which uses a diffraction grating to separate a multi-wavelength optical signal from an input port into multiple spectral channels; a channel-interleaving assembly (e.g., an array of prisms) to interleave the spectral channels into two channel groups; and an “augmented relay system” to relay the interleaved channel groups onto two separate arrays of channel micromirrors, respectively. The channel micromirrors are individually controllable and pivotable to reflect the spectral channels into multiple output ports. As such, the inventive wavelength routing apparatus is capable of routing the spectral channels on a channel-by-channel basis and coupling any spectral channel into any one of the output ports.

Abstract: A reconfigurable multifunctional optical device has an optical arrangement for receiving an optical signal, each having optical bands or channels, and a spatial light modulator for reflecting the at least one optical signal provided thereon. The optical arrangement features a free optics configuration with a light dispersion element for spreading each optical signal into one or more respective optical bands or channels for performing separate optical functions on each optical signal. The spatial light modulator includes a micro-mirror device with an array of micro-mirrors, and the respective optical bands or channels reflect off respective micro-mirrors. The free optics configuration includes a common set of optical components for performing each separate optical function on each optical signal. The separate optical functions reflect off separate non-overlapping areas on the spatial light modulator. The separate optical functions include optical switching, conditioning or monitoring functions.

Abstract: An optical signal production and modulation system that enables a multiplexed optical signal to be created for transmission without the use of more traditional laser-based optical transceivers. The system includes a light source library and a plurality of modulating optical transceivers. The light source library receives a composite wavelength un-modulated light signal, amplifies it, and separates it into discrete signal channels. Each of these channels is sent to a modulating optical transceiver, which employs a combination of lenses, reflective components, and a pin diode to modulate the channel with the desired data to be carried. The modulated channel can then be forwarded for multiplexing and transmission via a communications network.

Abstract: A fiber optic device comprises an optical lens element having a focal length greater than 2 mm, and an optical signal source or receiver mounted at the focal plane of the optical lens element and operative to communicate optical signals with a selectively transparent interference filter through the optical lens element. Methods for the production and use of the fiber optic devices are also disclosed.

Abstract: An Optical Tapped Delay Line (OTDL) is combined with other known optical apparatuses to provide an add-drop multiplexer for a wavelength division multiplexing fiber optic network. Each output beam of the OTDL is spatially distinguishable in free space. This wavelength accessibility enables selection of one or more of the optical beams for adding or dropping. The system can be a fixed or tunable single channel add/drop system, a fixed or tunable multi-channel add/drop system, or a fully programmable add/drop system.

Abstract: Disclosed is an interleaver for an optical communication system. A dual collimator is combined with a first optical fiber acting as a light input port and one end of a second optical fiber spaced from the first optical fiber, and switches light advancing along the first and second optical fibers into parallel light. A beam splitter is arranged so that one surface is opposite to the dual collimator, and transmits one half of an input light and reflects the other half of the input light. A single collimator is arranged opposite to the other surface of the beam splitter, and combined with the other end of the second optical fiber so as to switch light advancing toward the other end of the second optical fiber into parallel light. An output optical fiber is arranged opposite to the other surface of the beam splitter and acts as a light output port.

Abstract: An optical add-drop multiplexer successively comprises a first ferrule, a first graded index (GRIN) lens with a bandpass filter attached thereon, an optical crystal, a second GRIN lens, and a second ferrule. An input and an output optical fiber are stationed in the first ferrule, and a dropping and an adding optical fiber are stationed in the second ferrule. An optical multiplexed signal from the input optical fiber is transmitted through the first GRIN lens to the bandpass filter. From the bandpass filter, an optical signal having a wavelength identical to a central wavelength of the bandpass filter is output to the dropping optical fiber, and other optical signals having other wavelengths are coupled with an optical signal from the adding optical fiber having a wavelength identical to the central wavelength of the bandpass filter and are transmitted to the output optical fiber.

Abstract: VCSEL array configurations for use with parallel WDM transmitters are disclosed. Transmitters that use several wavelengths of VCSELs are built up out of multiple die to avoid the difficulty of manufacturing monolithic arrays of VCSELs with different optical wavelengths. VCSEL configurations are laid out to insure that VCSELs of different wavelengths that destined for the same waveguide are close together.

Abstract: A demultiplexer for use in a wavelength-division multiplexed optical system including a first positive lens group, a negative lens group, and a second positive lens group in order from a dispersive element and a reflective element. In some embodiments the reflective element is a light modulator, such as an actuatable diffraction grating. In some embodiments the demultiplexer is a part of a dynamic channel equalizer. In embodiments having a light modulator, the modulation may occur during both a first pass and a second pass.

Abstract: This invention relates to a multiplexer with a DWDM function, mainly comprising two modules, and an optic fiber is linked between said two modules, in which several filters and reflection mirrors, inclined slabs, laser diodes, receiver, and optical detectors detecting reflection light are provided in each module; thereby, many groups of optic signals may be mutually transmitted in a line of optic fiber at the same time so that the volume of mutually transmitted signals may multiplies under the condition of no extra paved optic fibers required, and in order to effectively detect the variations of laser for promotion of the stability of the module, the laser diode and the optic detector are further located in a predetermined site and the inclined slab is used to draw the reflection light of the laser to the nearby optic detector detecting the reflection light.

Abstract: A connector to an optical fiber comprises a prism, a ferrule and an aspheric lens. The prism includes a triangular wedge element having a first surface, a second surface and a base. The ferrule guides the optical fiber so as to contact the optical fiber with the first surface of the prism. The aspheric lens is integrated on the second surface, the integrated aspheric lens being positioned so that the prism serves to redirect a light beam at an angle relative to an axis of the optical source input through total internal reflection by utilizing the base of the triangle wedge element. The aspheric lens serves to collimate the redirected light beam or focus the light beam before being redirected. This arrangement may, for example, be used within a WDM system to multiplex and de-multiplex several wavelengths of light, using a “zig-zag” optical path configuration and thin film filters to separate the wavelengths.

Abstract: An East-West separable ROADM particularly usable as a programmable N×M optical add/drop multiplexer with an efficient pass through of optical channels in a multi-wavelength communication system. The East-West separable ROADM uses a grating that separates multi-channel optical signals into a plurality of optical channels, and combines a plurality of optical channels into multi-channel optical signals. Programmable mirrors and beam steerers can direct each optical channel to any of a plurality of fibers coupled to the device.

Abstract: Apparatuses, methods, and systems are disclosed for controlling optical signal wavelength spacing by providing for simultaneous upconversion of a plurality of electrical signal on subcarrier frequencies of an optical carrier frequency with or without modulation of an electrical data signal onto the optical carrier frequency. The optical carrier lightwave is split into a plurality of split lightwaves upon which one or more electrical frequencies carrying information can be upconverted onto optical subcarriers of the lightwave carrier frequency. The relative spacings of the optical subcarrier lightwaves will thus be unaffected by variation in the carrier frequency. The optical subcarrier lightwaves can then be recombined to form the optical data signal carrying the plurality of information carried by the electrical frequencies.

Abstract: A network for distributing signals to a plurality of user apparatuses having a distribution unit with a plurality of ports, and a plurality of optical-fiber cables connected to the ports and suitable to make the plurality of ports of the distribution unit communicate with the plurality of user apparatuses. At least one of the plurality of optical-fiber cables is an electrically terminated optical cable having an optical cable with a single-mode optical fiber and an opto-electronic end portion mechanically and permanently connected to an end of the optical cable, and the opto-electronic end portion has an opto-electronic conversion device having an optic port optically aligned with and mechanically connected to, an end of the single-mode optical fiber.

Abstract: An optical module 31 is provided in which a wavelength division element 32 such as an optical multi-layer film or diffraction grating is united between the sides of lens blocks 3 of optical module units 1 and 6 opposed to optical fiber blocks 2. Only light with a wavelength ?i among light (wavelength components: ?1, ?2 . . . ?n) from an optical fiber 41 is transmitted through the wavelength division element 32 and enters an optical fiber 42 of the optical module unit 6. On the other hand, the light (wavelength components: ?1, ?2 . . . ?n??i) reflected at the wavelength division element 32 is taken out of an optical fiber 43 of the optical module unit 1.

Abstract: Methods and apparatus for multiplexing and demultiplexing optical signals. An interleaver having a modified Mach-Zehnder interferometer as a first stage is used as a wavelength division multiplexer. This first stage is combined with one or more cascaded stages, each having a beam splitter and an optical delay element. A light beam including a number of signals at different wavelengths is received. The beam is split such that approximately half of each signal is contained in one of two sub-beams. One of the two sub-beams passes through a delay element, which provides a phase shift. The two sub-beams are recombined and split again. Each wavelength adds constructively or destructively in the new sub-beams such that the signals are separated—some wavelengths are in one of the new sub-beams, some are in the other. One of these sub-beams is delayed, and the two are combined and split again, improving the separation.

Abstract: Optical signals are received from a free-space link by directing received light onto a plurality of microlenses and then directing light received through each of the microlenses into a respective single mode optical fiber (SMF). Light beams from the SMFs are combined into a single light beam in one SMF. The single light beam is amplified with a multi-wavelength fiber amplifier and attenuated with a variable optical attenuator. The power gain of the multi-wavelength fiber amplifier and the attenuation of the variable optical attenuator are controlled. The single light beam is directed into a fiber optic communication system that is optically coupled to the variable optical attenuator.

Abstract: A method of fabricating a WDM unit consists of attaching a first and a second GRIN lenses to opposite faces of a WDM filter. A dual fiber pigtail and a single fiber pigtail are mounted in corresponding glass tubes. The glass tube with the dual fiber pigtail and the glass tube with the single fiber pigtail are mounted on the second GRIN lens and the first GRIN lens respectively. The position of the dual fiber pigtail and the single fiber pigtail are adjusted with respect to the second GRIN lens and the first GRIN lens respectively to obtain the best optical property. The invention prevents the WDM filter from tilting during temperature variation by sandwiching the WDM filter in between the two GRIN lenses, and further prevents the WDM unit from increasing the reflection loss and insertion loss.

Abstract: An optical add-drop multiplexer 400 includes an optical demultiplexer 410 having an input port coupled to receive an wavelength multiplexed optical signal. The optical demultiplexer 410 has a plurality of outputs, each for carrying an optical signal at one of the plurality of wavelengths. Switch optics 440 includes a channel coupled to each output. Each channel of the switch optics includes an analog mirror 424 coupled to receive the optical signal for that channel. The analog mirror 424 is rotatable along at least one axis is able to reflect a received optical signal in more than two directions. Each channel also includes an in/out lens device 422 aligned to receive the optical signal from the analog mirror 424 in a pass mode and an add/drop lens device 426 aligned to receive the optical signal from the analog mirror device 424 in an add/drop mode.

Abstract: Method and system for selectively adding and dropping selected wavelength components &lgr;=&lgr;k1 and &lgr;=&lgr;k2 (1≦k1≦k2≦K) in a light signal having a sequence of wavelengths &lgr;k (k=1, 2, . . . , K), using a dual fiber collimator at each end of an OADM device that contains an optical filter that transmits a selected wavelength &lgr;k1 and reflects the other wavelengths &lgr;k. Connecting two optical communication terminals in a network allows addition and dropping of a selected wavelength. Estimated total optical insertion losses, between the common port and the express port, for 2×2 and 3×3 add/drop combinations are 0.4 dB and 0.8 dB, respectively.

Abstract: The inventive beam forming technique enables use of multimode optical fibers to couple a modulated optical beam from a radiation source to an optical emitting antenna, for free-space communications. The disclosure teaches a methodology for determining the angular and frequency spectrum parameters of the optical energy applied to the fiber as well as the parameters of the fiber so as to smooth speckle-pattern caused by multimode interference and to provide a speckle-pattern contrast at or below a maximum value at which free-space communication is most efficient.

Abstract: The present invention provides an improved wavelength division multiplexer (WDM) which utilizes a grating-based channel separator. The WDM includes an interleaved channel separator; and at least one channel separator optically coupled to the interleaved channel separator. The channel separator includes a grating. In a preferred embodiment, the channel separator also includes an alignment surface of the grating, a sleeve comprising a mount, the mount capable of contacting the grating, and an alignment plate coupled to an outer surface of the sleeve, wherein the alignment plate is capable of contacting the alignment surface of the grating. This grating-based channel separator affords a quick, easy, precise and reproducible positioning and alignment of grating block. Thus, the WDM is minimized in size while also reproducibly assembled with perfect alignment in a minimal amount of time.

Abstract: An optical arrangement and method are provided for receiving a light beam having a plurality of spectral bands and directing subsets of the spectral bands along optical paths to respective optical elements. The light beam is received at an input port. The optical elements which route the spectral bands are configured as a substantially planar array. A dispersive element is configured to angularly spread the light beam, after it has been collimated, into a plurality of angularly separated beams that correspond to the plurality of spectral bands. A first focusing element is disposed with respect to the dispersive element and with respect to the array of optical elements such that variation of focal length with wavelength of the separated beams is compensated by the field curvature of the optical system, and the final image surface is flattened.

Abstract: An East-West separable ROADM particularly usable as a programmable N×M optical add/drop multiplexer with an efficient pass through of optical channels in a multi-wavelength communication system. The East-West separable ROADM uses a grating that separates multi-channel optical signals into a plurality of optical channels, and combines a plurality of optical channels into multi-channel optical signals. Programmable mirrors and beam steerers can direct each optical channel to any of a plurality of fibers coupled to the device.

Abstract: A spatial light communication equipment being capable of providing compatibility between two communication equipments placed opposite to each other and of providing, with simplified configurations, highly accurate seizure and tracking capability and excellent beam directivity for ultra-long-distance communication. Angular error in a receiving beam is detected by an angle detector disposed on an optical axis of light reflected by a first reflecting plane of a beam deflector and, based on detected results, an angle deflected by the beam deflector is corrected.

Abstract: Improved designs of optical multiplexing/demultiplexing module are disclosed for use in multiplexing a composite optical signal into respective individual channels or wavelengths or demultiplexing individual channels or wavelengths into a composite optical signal. According to one embodiment, the optical multiplexing/demultiplexing module comprises an array of collimators, an array of optical filters and an array of mirrors. The collimators are boned to a common substrate after being aligned with a respect optical filter. Different from the prior art devices, the aligned positions of the collimators are secured or held up by preformed wedges. A bonding agent is then applied only to respective contacts between the collimators and the wedges. The wedges are further bonded to a common substrate to secure the collimators.

Abstract: An optical crossconnect constructed of micro -electromechanical systems (MEMS) tilt mirror arrays for selectively routing optical signals to optic fibers. The crossconnect includes a lens array for directing optical signals from a fiber array to the MEMS mirror array. Individual mirror elements in the mirror array reflect the optic signals to additional optic elements such as a planar mirror, a transmissive/reflective optical element or a second MEMS mirror array for routing the optical signals to output optic fibers.

Abstract: According to embodiments of the invention described herein, a system and apparatus are described that include a microprocessor that has light-emitting devices formed into it. The light-emitting devices are to emit lightwaves, or optical signals, that may be organized into optical data. An optical fiber, connected directly to the microprocessor, is to accept the light from the light-emitting devices on the microprocessor die and to transmit the optical data to other devices in a system.

Abstract: The present invention provides for a delay unit for optically generating time delays in signals comprising: a delay entrance plane, the delay entrance plane comprising at least one row of signal input positions, wherein each signal input position is adapted to receive an optical beam from a source; a delay exit plane, the delay exit plane comprising a respective number of rows of signal output positions, each signal output position is adapted to output the optical beam; and wherein each signal input position of a given row is connected by an optical fiber to a corresponding signal output position, each optical fiber of a given row being the same length as every other optical fiber of that row. Also provided are apparatus and methods for generating time delays in signals.

Abstract: An optical add/drop multiplexer capable of extracting signals from within a specified waveband in a group of signals containing various wavelengths, and then adding back a new set of signals also within the specified waveband. The multiplexer includes an optical filter plate, a plane reflector and three graded-index lenses. Using a single optical filtering plate and a plane reflector to carry out multiple reflections, intra-band isolation of light signals is improved and cost of production is reduced.

Abstract: The present invention relates to a collimator assembly for use in an optical switch. The collimator assembly includes an integrated LED/photodiode plane disposed in a dual microlens array. The integrated LED/photodiode plane results in a relatively simple way to manufacture high port count collimator arrays with integrated monitoring capabilities. The LED/photodiode plane can be readily produced using standard electronics manufacturing technology.

Abstract: A free space multiport wavelength router for directing channels of a received WDM optic signal to a plurality of output ports. The inventive router includes a lens which receives an incoming WDM signal and focuses the signal on a grating for angular displacement, as a function of wavelength, of the individual channels in the WDM signal. The angularly displaced channels are then collimated by the lens and provided to an array of optical elements. The array is oriented relative to the lens so that each element in the array receives and imparts an orthogonal displacement to a corresponding channel relative to the dispersement direction provided by the grating. The othogonally-dispersed channels are then reflected back to the grating and are output to select output optic fibers.

Abstract: In a device for regenerating a wavelength-division multiplex optical signal, the optical signal to be regenerated comes from an optical fiber and is injected back into the same optical fiber or into another fiber. The device comprises at least one dispersive medium for receiving the wavelength-division multiplex signal and emitting a corresponding dispersed wave into a free space and a saturable absorber which receives the dispersed wave and transmits a corresponding regenerated wave.

Abstract: An x-ray inspection system for automatically detecting nuclear weapons materials generates a high energy x-ray fan beam or a traveling x-ray pencil beam that traverses an object under inspection. An x-ray detector detects x-ray energy that passes through the object and provides a detected signal indicative thereof. The detected signal is processed to detect the presence of an area of very high x-ray attenuation within the object under inspection, which is indicative of nuclear weapons materials. Because of the high atomic number (Z) and high density of nuclear weapons materials Uranium and Plutonium, both of these materials attenuate (i.e., absorb) incident x-rays significantly more than ordinary materials. That is, very high Z materials such as nuclear weapons materials, produce no x-rays outside of their block of material because the x-rays are self absorbed within the very high Z materials.