| Patent Number |
Title Of Patent |
Date Issued |
| 7440169 |
Method for amplifying a time-varying optical signal and optical amplification unit |
October 21, 2008 |
| A method for amplifying a time-varying optical signal comprising the steps of: generating an auxiliary optical signal the amplitude of which is chosen to be complementary to at least the envelope of the amplitude of the optical signal, superimposing the auxiliary optical signal to the |
| 6925219 |
Device for a passive optical network |
August 2, 2005 |
| Passive optical networks are generally built from a central office and a plurality of passive optical nodes. Over a main path, optical signals are transmitted to the nodes. When a fault, e.g. a cable break, occurs on the main path, the optical signals are transmitted to the nodes over a |
| 6917734 |
Tunable optical device and optical system using the tunable optical device as coding filter |
July 12, 2005 |
| According to the present invention the tunable optical device comprises a first optical wave guide and a second optical wave guide defining a space between the two wave guides with space comprises the first cell with liquid crystal material and a second cell with liquid crystal material |
| 6831773 |
Bidirectional coding splitter |
December 14, 2004 |
| It is an object of the invention to provide a network topology for OCDM signals. Coding splitters combining both coding and splitting functions are provided. The coding splitters themselves can be made from cascaded Mach Zehnder filters which are located somewhere in the network and whic |
| 6775484 |
Receiver for receiving optical signals |
August 10, 2004 |
| A receiver (EMP1, . . . , EMPn) is disclosed for receiving optical signals from an optical transmission network (NET) serving to transmit coded, multiplexed optical signals. The receiver (EMP1, . . . , EMPn) includes a means (DEK1) for detecting the optical signals to be received, e.g., |
| 6728485 |
Optical network |
April 27, 2004 |
| An optical network for transmitting optical data signals is proposed, wherein a first network operates with a WDM method, a second network used a CDM method and a third network uses a time-division multiplex method. |
| 6671468 |
Light source and method for the transmission of spectrally coded data |
December 30, 2003 |
| A light source with a broadband frequency-periodic output spectrum for digital spectrally coded data, whereby the light source consists of a solid state laser that is frequency-modulated or phase-modulated within one bit period. |
| 6642872 |
Optical code converter for optical code division multiplex system |
November 4, 2003 |
| In OCDM systems, optical signals have hitherto been transmitted to the receiving end in the optical transmission channel assigned at the transmitting end. This type of transmission is rigid and makes possible only simple network topologies, such as, for example, point-to-point. The o |
| 6594056 |
Receiver for use in a transmission system for spectral-coded data as well as a method |
July 15, 2003 |
| A method for the reception of spectral-coded data, and a receiver, whereby an optical signal is decoded, converted into an electrical signal and amplified, and whereby the optical signal is modulated by the modulation of the synchronization of the optical filter in a first frequency, the |
| 6588950 |
Optical transmission system and transmitters and receivers |
July 8, 2003 |
| An optical transmission system with transmitters and receivers is proposed wherein a narrow-band CDMA transmission is combined with a WDM transmission and a point-to-point connection for up to 256 channels is provided. |
| 6404528 |
Receiver for an optical communications system and method for operating such a system |
June 11, 2002 |
| A receiver is disclosed for receiving coded optical a signals in an optical asynchronous communications system using a CDMA method based on periodic spectrum encoding. It has a first optical detector unit (PD1) and a second optical detector unit (PD2) which are preceded by a first period |
| 6215573 |
Receiver for an optical communications system, filter device, and method for operating such a sy |
April 10, 2001 |
| A receiver (R) is disclosed for receiving coded optical signals in an asynchronous optical transmission system using a CDMA method based on periodic spectrum encoding. The receiver (R) has a filter device (Rx) for decoding received signals as well as an optical detector unit (PD). The |
| 6163553 |
Laser for generating an optical comb |
December 19, 2000 |
| A laser for generating an optical comb is disclosed having an active laser medium enclosed in a resonator, a launching coupler for coupling pump light from a pump source into the active medium, an output coupler for coupling out the generated laser comb, and at least one optical filter |
| 6034801 |
Transmitting device, transmitting apparatus and optical transmission system for optically transm |
March 7, 2000 |
| An optical transmission system (SYS), e.g. a cable television distribution network, contains at least one transmitting device (SEN), an optical transmission network (NET) and a number of receiving devices (EMP). In order to transmit analog electrical signals, e.g. television signals in |
| 6011637 |
Optical network unit and center of an optical communication network |
January 4, 2000 |
| Optical communication networks (NET) transmit bidirectionally information between a center (OLT) and a plurality of optical network units (ONU) which are connected with each other by optical fiber links. The communication network (NET) of the invention operates with composite signals |
| 5959766 |
Optical amplifier device |
September 28, 1999 |
| An optical amplifier device (REG) comprises a variable optical attenuator (DG), a control unit (CTRL), and an optical amplifier (EDFA). The gain of the amplifier (EDFA) and the attenuation of the attenuator (DG) are adjusted by the control unit (CTRL) based on a correlation (KOR) of the |
| 5889803 |
Resonator for electromagnetic waves with a stabilizer and method for stabilizing the length of t |
March 30, 1999 |
| A resonator (1) for electromagnetic waves with a stabilizer can, for example, be part of a mode-coupled fiber laser. The stabilizer (2) is provided to stabilize the effective length of the resonator (1). Stabilization is accomplished in a first embodiment via two temperature controll |
| 5786913 |
Optical TDMA ring network with a central transmitting and receiving device |
July 28, 1998 |
| An optical ring network with a plurality of network elements (#1, . . . , #N) is disclosed which contains only a single laser diode (2). This laser diode (2) is controlled to produce optical pulses of constant repetition frequency. Each network element (#1, . . . , #N) includes an add-dr |
| 5784506 |
Frequency-encoded optical CDMA transmission system and optical receiver therefor |
July 21, 1998 |
| An optical frequency-encoded CDMA transmission system is presented in which received optical signals are decoded in the electric part of an optical receiver (12). To that end, the optical receiver (12) has a single photodetector (6) which converts received light into an electric signal, |
| 5708670 |
Mode-locked fiber laser having an optical path length controller for a fiber resonator |
January 13, 1998 |
| The pulse repetition frequency of an optical pulse generator built with a fiber laser (LAS) is synchronized to a fixed clock frequency (fc). The synchronization is accomplished via means (M) for changing the optical path length of the resonator (RES), which is controlled by a signal from |
| 5546414 |
Mode-locked fiber ring laser |
August 13, 1996 |
| A passively mode-locked fiber ring laser (LAS) is disclosed for generating optical pulses whose repetition frequency is settable. The mode-locked fiber ring laser (LAS) contains an erbium-doped fiber (ER), a ring resonator (RES), a pump-light source (PUMP), an optical modulator (MOD), |
| 5544192 |
Optically pumped bistable laser |
August 6, 1996 |
| An optically pumped bistable laser (LAS) with an active laser condition and an excited inactive condition is presented. The bistable laser (LAS) comprises an erbium-doped fiber (ER), a resonator (RES), a pumping light source (PUMP), and optical isolator (ISO), a wavelength-dependent coup |
| 5499135 |
Optical amplifier |
March 12, 1996 |
| Known optical amplifiers, which are used in a light transmission path to amplify the light signals to be transmitted, have the disadvantage that the semiconductor lasers, used as pump lasers therein, are very sensitive to feedback.According to the invention, the operating current of such |
| 5453872 |
Fiber-optic amplifier as wavelength converter |
September 26, 1995 |
| An optical system includes a fiber-optic amplifier having a section of optical waveguide doped with a rare-earth element and a pump-light source for emitting pump light, the fiber-optic amplifier receiving signal light of a first wavelength and outputting at least signal light of a secon |
| 5195149 |
Fiber optic amplifier |
March 16, 1993 |
| To increase the pump efficiency in a fiber-optic amplifier, the pump coupler (2) is fabricated from a fiber whose mode field diameter for the pump light is adapted to the mode field diameter of the active length of fiber (7).In an alternative solution, the arm of the pump coupler (2) cou |
| 5119230 |
Optical fiber coupler amplifier |
June 2, 1992 |
| Conventional optical amplifiers for the amplification of optical signals propagating in an optical waveguide use a first light source for the production of pump light, by means of which an active laser substance is excited to a first energy level above its upper laser level. According to |
