Abstract: A method of eliminating the non-linearities associated with the remote feedback sensor, such as a quad position detector, used in a micro-electro-mechanical (MEM) mirror assembly. The incoming beam transmitted from a remote optical wireless link is first polarized, and then a single detector is employed to detect the polarization for the receiver. The single detector eliminates the non-linearity associated with a quad position detector, since the space between the quad detectors is eliminated.

Abstract: A MEMS-based optical, wireless communication system (10) that is comprised of a receiving and transmitting optical unit (12) that is further comprised of a transmitting subsystem (14) and a receiving subsystem (60), both of which are controlled by a microcontroller (16) and firmware (96). The system (10) is designed to allow a first unit (12) to transmit through free space a modulated laser beam (39) that is received by a second unit (12) located within line-of-sight of the first unit (12). Conversely, the second unit (12) can likewise transmit a modulated laser beam (39) that is received by the first unit (12) or other line-of-sight units (12). The system (10) features a MEMS mirror assembly (34) that operates in combination with a quad sensor (100). The combination allows fast, precise tracking and compensates for atmospheric disturbances associated with optical communication namely, building sway, wind and scintillations caused by changes in the refraction index of the atmosphere.

Abstract: An Improved Infrared Signal Communication System and Method Including Transmission Means Having Automatic Gain Control is disclosed. Also disclosed is system and method that adjusts signal transmission power in response to incident signal power amplitude. The preferred system includes a control signal loop within the signal receiving system, and the system further includes a signal transmitting system that is responsive to the control signal loop. The preferred system includes manual, semi-automatic and automatic modes of operation. Still further, the preferred method includes at least two Ir-enabled appliances “stepping” each other “down” in transmit power in response to directives issued by the other Ir-enabled appliance.

Abstract: This invention provides a dynamic interconnection system which allows to couple a pair of optical beams carrying modulation information. In accordance with this invention, two optical beams emanate from transceivers at two different locations. Each beam may not see the other beam point of origin (non-line-of-sight link), but both beams can see a third platform that contains the system of the present invention. Each beam incident on the interconnection system is directed into the reverse direction of the other, so that each transceiver will detect the beam which emanated from the other transceiver. The system dynamically compensates for propagation distortions preferably using closed-loop optical devices, while preserving the information encoded on each beam.

Abstract: A hybrid wireless optical and radio frequency (RF) communication link utilizes parallel free-space optical and RF paths for transmitting data and control and status information. The optical link provides the primary path for the data, and the RF link provides a concurrent or backup path for the network data, as well as a reliable and primary path for the control and status information. When atmospheric conditions degrade the optical link to the point at which optical data transmission fails, the hybrid communication link switches to the RF link to maintain availability of data communications. The switch may occur automatically, based on an assessment of the quality of the optical signal communicated through the optical path.

Abstract: A satellite constellation has a plurality of satellites. Each of the satellites has an RF ground link for communicating with a ground station and an optical link for communication with at least one of the plurality of satellites. Each of the satellites has a reconfigurable optical transmitter for sending and receiving data streams. Each reconfigurable optical transmitter has a first optical carrier associated therewith and a reconfigurable optical receiver. The plurality of satellites is arranged to have a first subset of satellites. The first subset of satellites is configured to communicate. The plurality of satellites is reconfigured to have a second subset of satellites having at least one different satellites than that of said first subset. The second subset supercedes the first subset. The second subset of satellites is configured to communicate. Various subset around the globe may form local area networks. The local area networks are preferably optically coupled to form a wide area network.

Abstract: A filtering technique for a free space communication that features encoding and decoding of signals employing a filtering apparatus that includes a bulk holographic transform function. Employing the encoding and decoding technique facilitates providing a great number of channels of communication in a unit volume while preventing unwanted cross-talk between the communication channels. In addition, secure communication links between transmitters and receivers may be provided.

Abstract: A point-to-multipoint bi-directional wide area telecommunications network employing atmospheric optical communication. The network comprises a primary transceiver unit, a plurality of subscriber transceiver units and an optical router. The primary transceiver unit may send data destined for the subscriber transceiver units through the optical router, and the subscriber transceiver units may send data destined for the primary transceiver unit through the optical router. The primary transceiver unit and optical router communicate by means of light beams which are transmitted through the atmosphere. Similarly, the optical router and the subscriber transceiver units communicate by means of light beams which are transmitted through the atmosphere.

Abstract: The invention pertains to an electro-optical connector module comprising a connection part, at least one optical transmitter circuit and/or optical receiver circuit and at least one electro-optical converter for respectively converting electrical signals into optical signals or vice versa. The module further comprises at least two substantially flat and substantially parallel electrically insulating sheets on which the transmitter circuit and/or receiver circuit and the converter are mounted. It is preferred that the connector module according, comprises at least one optical transmitter circuit, at least one optical receiver circuit and at least two electro-optical converters for respectively converting electrical signals into optical signals and vice versa, wherein the optical transmitter circuit and a first converter are mounted on a first sheet and the optical receiver circuit and a second converter are mounted on a second sheet.

Abstract: In one embodiment of the invention, a first absorbing layer is on a substrate and/or a second absorbing layer is on a heat-activated adhesive. If the IR source that supplies IR radiation is present on the substrate-side, then the absorption percentage of the substrate is less than the absorption percentage of the first absorbing layer if present and less than the absorption percentage of the second absorbing layer if present. If the IR source that supplies IR radiation is present on the “encapsulation cover”-side, then the absorption percentage of the encapsulation cover is less than the absorption percentage of the first absorbing layer if present and less than an absorption percentage of the second absorbing layer if present. The substrate and the encapsulation cover have a low thermal conductivity.

Abstract: Infrared communications scheme for use in an embedded system. According to a preferred embodiment, the invention comprises the use of an infrared communications scheme, according to IrDA protocol, which is utilized to transmit and receive data optically between circuit cards housed within an enclosed, embedded system. Preferably, each respective circuit card is provided with an LED and photodiode to respectively transmit and receive data optically. As such, wire connections are eliminated and allows the systems and methods of the present invention to withstand a greater degree of vibration and shock than that of the prior-art systems and methods. Moreover, the systems and methods of the present invention provide increased reliability and provide greater electrical isolation between modules than prior-art systems and methods.

Abstract: A free-space optical communication apparatus includes a storage unit which stores angle-setting information for the mirror for communicating with each of the plurality of other apparatuses, a mirror driving unit which drives the mirror to an angle corresponding to the stored angle-setting information, an optical detecting unit which, on one occasion for communicating with a specified communication apparatus among the plurality of other apparatuses, detects the incident state of an optical beam sent from the specified apparatus, and a control unit which, based on the detected incident state of the optical beam, determines angle-correcting information for correcting the stored angle-setting information for the specified apparatus, and which, on the next occasion for communicating with the specified apparatus, uses the mirror driving unit to drive the mirror to an angle corresponding to the angle-setting information corrected by the angle-correcting information.

Abstract: The invention relates to a method for communicating multimedia data between electronic devices by means of IR ray, which comprises the steps of converting data to be transmitted into a document by a document processing program installed in an electronic device for transmission, appending a filename extension thereto for classifying the document, transmitting the document through an IR transceiving control signal by an IR transceiver of the said electronic device, receiving the control signal as an indicative of the transmitted document by another electronic device for receiving, and identifying and processing the received document based on the filename extension thereof so as to create an identifiable data.

Abstract: An optoelectronic transceiver including an optoelectronic transmitting unit disposed along an optical axis and having a radiation-emitting layer region and an active radiation-sensitive layer region. The optoelectronic transceiver further including an optoelectronic receiving unit disposed along the optical axis and is disposed in bridge-like fashion above the optoelectronic transmitting unit. The optoelectronic receiving unit having an active radiation-sensitive layer region disposed perpendicular to the optical axis and located in a thin membrane, which is disposed immediately in front of the radiation-emitting layer region of the optoelectronic transmitting unit, and a radiation-emitting layer region.

Abstract: A portable transceiver of one or more signals includes an input, frequency modulation, a splitter and a plurality of lasers in a transmitter module. A receiver module includes a Mangin mirror aligned with an input aperture. A photodiode receives the signal from the mirror for subsequent demodulation. An interference filter is arranged between the mirror and the photodiode. The filter is hemispherical, having a center of curvature at the focal point of the mirror. The transceiver may include a video camera and gyro-stabilizer accessories. A visual siting scope is aligned with the lasers and the receiver. A separate transceiver for ethernet input signals interfaces with a 10/100 ethernet switch and does not employ frequency modulation.

Abstract: Internal communication signals in a stored program controlled system comprising a plurality of units configured to process signals are provided by a free space optical beam line which is proximal to all of the plurality of units. The free space beam line is configured to contain optically encoded signals which comprises signals transmitted between and/or among the plurality of units. Each unit includes a probe for injecting optically encoded signals in the free space beam line and/or and for receiving optically encoded signals from the free space beam line. Advantageously, there may be a first terminal at a first end of the beam line to configure to transmit and terminate the optically encoded signals and a second terminal unit at the second end of the free space beam line configured to transmit and terminate the optically encoded signals.

Abstract: An optical transceiver includes an opaque element having a concave reflective surface arranged in a path of each of an outgoing and an incoming light signal, the reflective surface configured to redirect the paths of the respective light signals. An optical detector is arranged facing the reflective surface. The optical detector is configured to detect a redirected incoming light signal from the reflective surface and to generate therefrom a receive signal proportional to the incoming light signal. An emitter is arranged facing the reflective surface. The emitter is configured to generate the outgoing light signal proportional to a transmit signal. A lens assembly is arranged between the reflective surface of the opaque element and both the optical detector and the emitter. The lens assembly is configured to couple the redirected incoming light signal to the optical detector and to couple the outgoing light signal to the reflective surface.

Abstract: A receiving apparatus and transmitting apparatus capable of reliably transmitting and receiving a high speed optical signal and a communication system using the same, wherein provision is made of a transmitting apparatus comprising a conversion circuit for converting serially input data to a plurality of bits of parallel data given predetermined information and an LED array comprised of LED units of at least a number corresponding to the number of bits of the parallel data from the conversion circuit arranged in an array, wherein the LED units are controlled in light emission in parallel based on bit information of corresponding parallel data to emit information light dispersed in a spatially predetermined range, and of a receiving apparatus having a photo-diode array comprised of a plurality of photo-diodes for emitting electric signals of levels in accordance with amounts of light received arranged in an array, wherein the photo-diodes output electric signals in parallel, for selecting information in accord

Abstract: Optical transceivers include a diffractive optical element (DOE) attached to a surface of a prism or other optical support. The DOE is configured to direct an input optical signal to a planar or curved reflective surface, or receive an output optical signal from the planar or curved reflective surface at angles greater than a critical angle in the prism. In some examples, the optical support includes one or more curved reflective surfaces and the DOE is a hologram. Such optical transceivers include a reflective surface that is rotatable with respect to the DOE, or with respect to a selected communication direction and the DOE for selection of a transmission or reception direction. The optical supports of such optical transceivers can be mounted to a window, and include a reflective region configured to total internally reflect optical signals. Selection of a communication direction is based on a rotation of the rotatable reflective surface.

Abstract: Optical transceivers include a diffractive optical element (DOE) attached to a surface of a prism or other optical support. The DOE is configured to direct an input optical signal to a curved reflective surface or receive an output optical signal from the curved reflective surface at angles greater than a critical angle. In some examples, the optical support includes one or more curved reflective surfaces and the DOE is a hologram. Such optical transceivers can be provided with optical mounts configured for attachment to a building window.

Abstract: Integrated glass ceramic spacecraft include a plurality of glass ceramic components including molded, tempered, annealed, and patterned glass ceramic components coupled together for forming a support structure or frame or housing through which is communicated optical signals through an optical communications grid and electrical signals through an electrical communications grid, with the optical communications grid and electrical communication grid forming a composite electrooptical communications grid for spacecraft wide intercommunications. The support structure multifunctions as a frame, a housing, a support, a thermal control system, and as part of an electrooptical communications grid while encapsulating a plurality of optical, electronic, electrical, and MEMS devices between which is communicated the electrical and optical signals over the electrooptical communication grid.

Abstract: An Infrared Data Association (IrDA) communication range (109) (e.g., 1 meter) of an IrDA compliant portable device (201) is increased to an extended range infrared communication (ERIC) range (209) (e.g., 2 to 40 meters) by extending a transmission range over an uplink channel (207) from the portable device (201) up to a base station (202) and by extending a transmission range over the downlink channel (208) from the base station (202) down to the portable device (201).

Abstract: The present invention is directed to a reconfigurable data communications system. The system includes a removable optical backplane connector with a first end and a second end, a first data communications card, and a switch fabric card. The first data communications card includes an optical port configured to receive the first end of the removable optical backplane connector. The switch fabric card has a plurality of optical ports adapted to receive the second end of the removable optical backplane connector.

Abstract: A window-mounted positionable collector comprising a base that is secured to a window. An inner rotatable hollow wedge-cut member may be rotated about the base to produce a first degree of freedom, while an outer rotatable hollow wedge-cut member may be rotated about a top end of the inner rotatable hollow wedge-cut member to provide a second degree a freedom. The combination of the first and second degrees of freedom enables the optical axis of an optical collector operatively coupled to the outer rotatable hollow wedge-cut member to be directed along any direction falling within a cone of angulation defined by acute angles corresponding to the angles of the wedge cuts defined in the rotatable hollow wedge cut members. In one embodiment, a cover is connected to a top end of the outer rotatable hollow wedge-cut member to form a sealed volume, whereby the apparatus may be secured to the window by applying a vacuum to the sealed volume.

Abstract: A wireless communications link between a communication line connector and at least one audio-visual device is provided. The communications link preferably includes a communication line side unit, including: (a) a communication line side connector for engagement with the communication line connector for bidirectional audio-visual data communication, providing communication between a communication line and the at least one audio-visual device, (b) a communication line side infrared transmitter adapted to transmit diffuse infrared radiation corresponding to the data communication, and (c) a communication line side infrared receiver adapted to receive diffuse infrared radiation corresponding to the data communication.

Abstract: An optical transmission device configured as a central node, wherein each central node has dedicated pixels for receiving data and transmitting optical data so destination addressing is not required. The network is configured such that transmission on any particular receiver reserved pixels results in data being sent to a predetermined node. In particular, the star topology is configured as a receiver reserved scheme. The device is formed by constructing central node of transmitters and receivers that are attached to a silicon substrate with a processing means, and the optical interface to the transmitters and detectors on the central node establish a one-to-one correspondence with an individual fiber optic cable. The fiber optic cables are reconfigurable to different topologies or interconnections as each fiber optic cable has a known destination on the central node. Various topologies are possible using a star node as the building block.

Abstract: An optical signal transceiver subassembly is mounted on a lead frame for further attachment to an electronic printed circuit board. The optical subassembly is comprised of a solid-state laser, a pair of photo-detectors, an over-mold of transparent material having shapes forming the exposed surface thereof, the surface and a selective silvering of a portion thereof defining a beam-splitter mirror and an interior reflective focusing surface, preferably in the shape of a partial cylindrical surface. The beam-splitter mirror is lightly silvered and the cylindrical surface is silvered to enhance the reflection of the laser beam. The optical subassembly is further enclosed with a housing incorporating a pair of lenses and alignment pins. The lenses focus the data stream of optical light signals onto the end of the outgoing optical fiber and the data stream of optical light signals from the incoming optical fiber onto and through the beam-splitter and onto a first photo-detector.

Abstract: A filtering technique for free space communication that features an improved extinction ratio by providing a filter that employs a bulk holographic transform function and a polarizing film. In this manner, a greater number of channels of communication may be provided in a unit volume while preventing unwanted cross-talk between the communication channels. To that end, the system includes a source of energy to direct energy along a path, a detector disposed in the path, and a filter. The filter has a surface upon which a polarizing film is disposed and a holographic transform function recorded throughout a volume thereon.

Abstract: A reflective optical apparatus for a free-space optical communication system includes a housing, an optical transceiver, a reflective member and the protective window. The housing has a front opening. The reflective member is mounted in the housing and has a reflective surface with a focal point, which faces the front opening. The optical transceiver is mounted at the focal point of the reflective surface. The protective window is mounted in the housing between the transceiver and the front opening of the housing. Consequently, the reflective member can be made of machinable materials, such as composite materials and can be machined precisely to form the reflective surface with an exact curvature and smooth surface. The materials and sizes of the reflective member are not restricted, and the objectives of being low cost and easy to machine in fabrication for the reflective optic apparatus are accomplished.

Abstract: A free space optical data communications system, including transceiver nodes employing common optics in both the transmit and receive subsystem, is disclosed. Likewise, a beacon is disclosed utilizing some of the common optics as well. In one embodiment, a double-faced mirror cooperates with a beacon, a primary mirror, and the transmit and receive subsystems. In one other embodiment, the beacon is located in front of the primary mirror. In still another embodiment, the common optics includes TEM11 mode signal separation using phase plates. A tracking system in each embodiment maintains alignment of the optics with a second node by generating a correction vector responsive to the incoming signal from its companion node.

Abstract: A transceiver that includes a receiver configured to receive a data signal, a controller, a first memory that includes a first table associated with a first set of gain values and a second table associated with a second set of gain values, and a second memory accessible by an external host is provided. The controller is configured to access a first value associated with a strength of the data signal from the receiver, access a second value associated with the first value from the first table, generate a third value using the second value, and store the third value in the second memory.

Abstract: A method simultaneously aligns the two sets of optical wireless link transceiver mirrors such that light traverses a path from the transmitting laser off an outbound mirror, through free space, off the inbound mirror of the remote station, and finally onto the receiving element in the remote station.

Abstract: This invention describes an optical communications system for optically networking computers and other devices together in a multi-user environment in a cost effective manner. This is accomplished through the use of low power (eye safe intensity) lasers, light emitting diodes, or photo diodes, to connect users in a time shared fashion through an optical multiplexing system (the optical access point) which can direct and manage the networking connection to each user device (user optical transceiver) independently. Both the optical access point and the user optical transceiver are capable of dynamically adjusting a beam to locate and align with each other.

Abstract: A free-space optical communication system utilizes an optical repeater system, which is installed between transmitting terminals and receiving terminals. Each optical receiver of the repeater system connects via a separate optical beam with one or more of the transmitting terminals. Two or more optical transmitters of the repeater system preferably communicate with each of the receiving terminals. Modules of the repeater system are spatially separated far enough from each other to prevent cross-talk between information on the beams, either at the receivers of the repeating system or at the receiving terminals. Receiving elements in the repeater system and/or in the destination receiving system preferably convert angular beam separation into spatial resolution between beam detectors.

Abstract: A system for tracking a projectile utilizing a laser beam modulated by an acousto-optic cell. Transponders distributed on hemispheres around the rear of the projectile detect the scanned beam and actively transmit a narrow optical beam back to a ground-based receiver in response to a detection of the scanned beam. IFF information can be modulated onto beam actively transmitted from the transponder. The system provides active two-way communications with comparatively simple components.

Abstract: A system is provided for automatically dialing a number stored in an electronic organizer on a telephone. The system comprises an electronic organizer including memory for storing a plurality of telephone numbers therein, an input device for selecting one of the telephone numbers, and a communicator for transmitting digits of the selected telephone number. The system further includes telephone circuitry adapted to dial digits of the selected telephone number upon the receipt thereof. Further provided is an interface including a communicator in communication with the communicator of the electronic organizer for receiving the digits therefrom and transmitting the same to the telephone circuitry.

Abstract: This disclosure relates to a laser communication system which allows changing the direction of reception and transmission without external manipulation of the system container. The basic unit of the system is a narrow-band transmitting-receiving telescope apparatus which includes a rotating diffraction grating and an independently rotating stage with mounted combination of photodetector for reception and laser for transmission and a focusing system concentrating the beam reflected from the grating onto the photodetector of the combination or sending a beam from laser of the combination onto the grating. The selection of definite angles for signal transmission-reception is realized by corresponding rotation of grating and rotating stage to the proper angles. The apparatus is intended for spectrally selective transmitting or receiving of optical radiation.

Abstract: A method of full-duplex electromagnetic communication wherein a pair of data modulation formats are selected for the forward and return data links respectively such that the forward data electro-magnetic beam serves as a carrier for the return data. A method of encoding optical information is used wherein right-hand and left-hand circular polarizations are assigned to optical information to represent binary states. An application for an earth to low earth orbit optical communications system is presented which implements the full-duplex communication and circular polarization keying modulation format.

Abstract: A transceiver including a controller, a first memory that includes first information, and a second memory accessible by a host is provided. The controller is configured to copy the first information from the first memory to the second memory.

Abstract: The present invention provides an apparatus and method for free space optical communication. The apparatus includes a first optical source configured to generate a first optical beam, a first optical beam carrier optically aligned with the first optical source and configured to propagate at least a portion of the first optical beam, and an extended source optically aligned with the first optical beam carrier and configured to output an extended source optical beam. The extended source can include an extended source telescope configured to direct at least a portion of the first optical beam to output the extended source optical beam into free-space. Alternative the extended source can include a large core fiber optic cable configured to propagate at least a portion of the first optical beam exercising additional modes of the large core fiber cable to generate the extended source optical beam.

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: A battery module transceiver for extending the operational range of an infrared remote controller is disclosed. The battery module comprises: a battery power supply received within the battery module transceiver which provides power for the infrared remote controller and a transceiver received within the battery module transceiver. The transceiver has a detector for detecting a radio frequency pulse accompanying a first infrared signal generated from the infrared remote controller and a transmitter for generating a radio frequency signal in response to the radio frequency pulse.

Abstract: A holographic element (HOE) with multiple apertures formed in a single substrate for use an optical communication system. The multi-aperture HOE can be use instead of an optics unit having one or more separate optical elements for each aperture needed by an optical transmitter, receiver or transceiver. The single substrate reduces complexity and cost relative to conventional system that the use separate optical elements to implement the optics unit.

Abstract: An optical bidirectional transceiver module includes a module body having an opening, an inner hollow space and a fiber pin pushed through the opening into the inner hollow space. The fiber pin has a centric bored hole in which a light-conducting fiber is guided. A wavelength-selective filter or a beam splitter is located at a beveled end surface of the fiber pin. Radiation from an externally coupled light waveguide is emitted through the light-conducting fiber and reflected at the filter to a first optoelectronic component (transmitter). Received light radiation passes through the filter and impinges on a second optoelectronic component (receiver).

Abstract: A bidirectional optical link for communication between a first data unit and a second data unit using a single optical source. In a broad aspect it includes a modulator/optical receiver system that includes a splitter element; a receiver element and a return modulator. The splitter element receives an incoming modulated optical signal from an optical source associated with a first data unit. It splits the incoming optical signal into a received optical portion and an outgoing optical portion. The receiver element detects the received optical portion and converts the received optical portion to an electrical signal to be communicated to a second data unit. The return modulator element modulates the outgoing optical portion and transmits the modulated outgoing optical portion to the first data unit. The modulation of the outgoing optical portion allows the use of a single, shared optical source.

Abstract: A free-space optical (FSO) transceiver head and mounting assembly to enable the FSO transceiver head to be mounted to a window. The FSO transceiver head has a binocular configuration including respective sets of transmit and receive optics configured to facilitate transmission and reception of optical signals. The mounting assembly provides a pair of adjustable axes to enable the FSO transceiver head to be rotated and tilted relative to an axis that is normal to the window. The mounting assembly also provides adjustable feet for fine-pointing. Upon assembly, the entire apparatus has a depth of approximately 3½ inches, enabling it to be deployed in a standard-sized window frame behind a window blind. The apparatus may also be deployed in vehicle windows and out-building windows. A breakaway feature is also provided such that the apparatus will break free from a window rather than having the window break when a sufficient force is applied to the mounting assembly and/or transceiver head.

Abstract: A point-to-multipoint bi-directional wide area telecommunications network employing atmospheric optical communication. The network comprises a primary transceiver unit, a plurality of subscriber transceiver units and an optical router. The primary transceiver unit may send data destined for the subscriber transceiver units through the optical router, and the subscriber transceiver units may send data destined for the primary transceiver unit through the optical router. The primary transceiver unit and optical router communicate by means of light beams which are transmitted through the atmosphere. Similarly, the optical router and the subscriber transceiver units communicate by means of light beams which are transmitted through the atmosphere.

Abstract: An optical communications system includes spaced apart first and second optical elements. Each optical element has a focal plane. A plurality of optical transmitters, each of which includes a light emitting element, are disposed spaced apart from each other in the focal plane of the first optical element. A plurality of optical receivers, each of which includes a light receiving element, are disposed spaced apart from each other in the focal plane of the second optical element. Optical signals emitted by the light emitting elements are received at first optical element and combined into a single beam. The single beam is received at the second optical element. The second optical element separates the single beam into separate optical signals. The separate optical signals are focused onto the receiving elements.

Abstract: A tracking system and method in an optical communications system utilizing an optical communications beam. In one embodiment, the disclosed tracking system includes a tracking detector having a plurality of regions coupled to a corresponding plurality of tracking channel circuits. Each of the tracking channel circuits includes an optical detector coupled to receive the optical communications beam. The peak-to-peak amplitude modulation in the optical communications beam is measured by substantially reducing or removing a direct current (DC) offset present in the optical communications beam. In one embodiment, after the DC offset is substantially reduced or removed, the signal is then amplified and converted into an all positive signal, which is then filtered. The filtered signal is one of a plurality of tracking signal outputs, which are input to an alignment circuit.

Abstract: An optical transceiver for detecting an incoming light beam and for transmitting an outgoing light beam along a common optical axis is provided. Such an optical transceiver provides a compact optical transceiver that is suitable for a wide variety of applications.