Multiwavelength data communication fiber link

An optical multichannel data communication link for transmitting data from a transmitter to a remote receiver;

• said link comprising a source connected to said transmitter;
• means for converting each channel of data to a modulated light wave from said source;
• wavelength division multiplexer means, at the transmitter, having paraxial optics for multiplexing the light waves to produce a multiplexed signal;
• multimode fiber optic means, connected to the multiplexer means, for passing the multiplexed signal to the remote receiver;
• wavelength division demultiplexer means having paraxial optics for demultiplexing the multiplexed signal at the receiver to produce demultiplexed light waves at the receiver;
• and means for reconverting each of the demultiplexed light waves for use by the receiver;
• said wavelength division multiplexer means and demultiplexer means having a littrow reflection grating and lens means which are paraxially aligned with said multimode fiber optic means to provide channel separation of less than 50 nm;
• wherein the means for converting comprises an LED or an edge emitting LED having wavelength separation, .DELTA..lambda., and linewidth, .delta..lambda., such that .delta..lambda./.DELTA..lambda..ltoreq.2(1-d/b), where d is the fiber core diameter and b is the cladding diameter.

An optical multichannel data communication link for transmitting data from a transmitter to a remote receiver, said link comprising a laser diode source coupled to said transmitter;

• means for modulating said source with each channel of data to generate a modulated light wave;
• wavelength division multiplexer means, at the transmitter, having paraxial optics for multiplexing the light waves to produce a multiplexed signal;
• fiber optic means, connected to the multiplexer means, for passing the multiplexed signal to the remote receiver;
• wavelength division demultiplexer means having paraxial optics for demultiplexing the multiplexed signal at the receiver to produce demultiplexed light waves at the receiver;
• and means for reconverting each of the demultiplexed light waves for use by the receiver;
• said fiber optic means comprising a single-mode fiber;
• said wavelength division multiplexer means and demultiplexer means having fibers, a littrow reflection grating, and lens means which are paraxially aligned with said single-mode fiber optic means, said link being optimized to minimize cross talk by one of
• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

An optical multichannel data communication link for transmitting data from a transmitter to a remote receiver, said link comprising a multimode laser diode source coupled to said transmitter;

• means for converting each channel of data to a light wave from said source;
• wavelength division multiplexer means, at the transmitter, having paraxial optics for multiplexing the light waves to produce a multiplexed signal;
• multimode fiber optic means, connected to the multiplexer means, for passing the multiplexed signal to the remote receiver;
• wavelength division demultiplexer means having paraxial optics for demultiplexing the multiplexed signal at the receiver to produce demultiplexed light waves at the receiver;
• and means for reconverting each of the demultiplexed light waves for use by the receiver;
• said wavelength division multiplexer means and demultiplexer means having fibers, a littrow reflection grating, and a lens which are paraxially aligned with said fiber optic means, said link being optimized to minimize cross talk by one of
• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

An optical multichannel data communication link for transmitting a multichannel signal from a source to a remote receiver, said link comprising transmitter means, optical path means, and receiver means;

• said transmitter means comprising a laser diode source, means for converting each channel of the signal to a light wave from the source, and wavelength dispersive means for multiplexing the light waves;
• said optical path means transmitting at least as many wavelengths as the number of channels and connecting the transmitter means to the receiver means;
• said receiver means comprising wavelength dispersive means for demultiplexing the light wave and detector means for detecting each of the demultiplexed light waves and reconverting the light waves for use by the remote receiver;
• said wavelength dispersing means having fibers, a littrow reflection grating, and lens means which are paraxially aligned with the optical path means, said link being optimized to minimize cross talk by one of
• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

An optical multichannel data communication link for transmitting a multichannel signal from a source to a remote receiver, said link having a known wavelength shift, d.lambda., and comprising transmitter means, optical path means, and receiver means;

• said transmitter means comprising a source, laser diode means for modulating said source with each channel of the signal to generate a light wave, and wavelength dispersive means for multiplexing the light waves;
• said optical path means transmitting at least as many wavelengths as the number of channels and connecting the transmitter means to the receiver means;
• said receiver means comprising wavelength dispersive means for demultiplexing the light wave and detector means for detecting each of the demultiplexed light waves and converting the light waves for use by the remote receiver;
• said wavelength dispersive means having fibers, a littrow reflection grating, and lens means which are paraxially aligned with the optical path means to provide channel separation of less than 50 nm
• said link optimized so that the b/d ratio for said fibers is set equal to (b/d).sub.c wherein (b/d).sub.c is determined from the equation (b/d).sub.c =2-.zeta..sub.d where b is the core to core distance between fibers and d is the diameter of the fiber cores, and wherein the (b/d).sub.c equation is solved for by substituting maximum loss, .zeta..sub.max, from the equation ##EQU60##

An optical multichannel data communication link for transmitting a multichannel signal from a source to a remote receiver, said link comprising transmitter means, optical path means, and receiver means;

• said transmitter means comprising a source, laser diode means for modulating said source with each channel of the signal to produce a modulated light wave, and wavelength dispersive means for multiplexing the light waves;
• said optical path means transmitting at least as many wavelengths as the number of channels and connecting the transmitter means to the receiver means;
• said receiver means comprising wavelength dispersive means for demultiplexing the light wave and detector means for detecting each of the demultiplexed light waves and reconverting the light waves for use by the remote receiver;
• said wavelength dispersive means having fibers, a littrow reflection grating, lens means which are paraxially aligned with the optical path means to provide channel separation of less than 50 nm;
• said link having a predetermined minimum dispersion loss, .zeta..sub.d, in accordance with the equation ##EQU61## where .zeta..sub.D is a function of b and d, and b is the core to core distance between fibers, d is the diameter of the fiber core, and k is the wavelength tolerance shift.

An optical multichannel data communication link for transmitting a multichannel signal from a source to a remote receiver, said link comprising transmitter means, optical path means, and receiver means;

• said transmitter means comprising a laser diode source, means for converting each channel of the signal to a light wave from said source, and wavelength dispersive means for multiplexing the light waves;
• said optical path means transmitting at least as many wavelengths as the number of channels and connecting the transmitter means to the receiver means;
• said receiver means comprising wavelength dispersive means for demultiplexing the light wave and detector means for detecting each of the demultiplexed light waves and reconverting the light waves for use by the remote receiver;
• said wavelength dispersive means having a littrow reflection grating and lens means which are paraxially aligned with the optical path means to provide channel separation of less than 50 nm;
• wherein the optical path means comprises fibers having a fiber geometry meeting the condition b/d=(b/d).sub.c, wherein b is the distance between adjacent fiber cores, d is the diameter of the core of the fiber, and (b/d).sub.c =1/(1-k.sub.o) where ##EQU62## where .DELTA..lambda. is the center wavelength separation of each light wave and d.lambda..sub.c is the maximum permissible wavelength variation from the center wavelength of each light wave.

An optical multichannel data communication link for transmitting data from a transmitter to a remote receiver, said link comprising a laser diode source coupled to said transmitter, means for converting each channel of data to a light wave from said source;

• wavelength division multiplexer means, at the transmitter, having paraxial optics, for multiplexing the light waves to produce a multiplexed signal;
• fiber optic means, connected to the multiplexer means, for passing the multiplexed signal to the remote receiver;
• wavelength division demultiplexer means having paraxial optics for demultiplexing the multiplexed signal at the receiver to produce demultiplexed light waves at the receiver;
• and means for reconverting each of the demultiplexed light waves for use by the receiver;
• said wavelength division multiplexer means and said wavelength division demultiplexer means comprising a wavelength division multiplexer/demultiplexer having paraxially aligned fibers, a lens, and a littrow reflection grating to provide channel separation of less than 50 nm, said fibers of said multiplexer having a b/d ratio different than the b/d ratio of said fibers of said demultiplexer, where b is the core to core distance between fibers and d is the diameter of the fiber core, said link being optimized to minimize cross talk by one of
• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

An optical multichannel data communication link for transmitting data from a transmitter to a remote receiver, said link comprising a source connected to said transmitter, means for modulating said source with each channel of data to generate a modulate light wave;

• wavelength division multiplexer means, at the transmitter, having paraxial optics for multiplexing the light waves to produce a multiplexed signal;
• fiber optic means, connected to the multiplexer means, for passing the multiplexed signal to the remote receiver;
• wavelength division demultiplexer means having paraxial optics for demultiplexing the multiplexed signal at the receiver to produce demultiplexed light waves at the receiver;
• and means for converting each of the demultiplexed light waves for use by the receiver;
• said wavelength division multiplexer means and said wavelength division demultiplexer means comprising a wavelength division multiplexer/demultiplexer having paraxially aligned fibers, a lens, and a littrow reflection grating to provide channel separation of less than 50 nm, said fibers of said multiplexer having a b/d ratio different than the b/d ratio of said fibers of said demultiplexer, where b is the core to core distance between fibers and d is the diameter of the fiber core, wherein the respective b/d ratio of the multiplexer and demultiplexer is due to a difference in the thickness of the cladding between the fibers in the multiplexer and demultiplexer respectively.

A multichannel data communication link for transmitting data from a transmitter to a remote receiver, said link comprising means for conditioning the signal from the transmitter, said means for conditioning being connected electrically to the transmitter, laser diode means for converting the signals output from the signal conditioning means, said laser diode means being connected to the signal conditioning means via one optical fiber per channel, wavelength division multiplexing means, at the transmitter, for multiplexing the outputs of the laser diode means and connected to the laser diode means via one optical fiber per channel, wavelength division demultiplexing means connected to the output of the multiplexing means via an optical fiber, detector means connected to the demultiplexing means via one optical fiber per channel, signal conditioning means connected electrically to the outputs of the detector means, and receiver means electrically connected to the outputs of the signal conditioning means, said multiplexing and demultiplexing means having paraxially arranged transmission optics, fibers, and a littrow broad band uniform reflection grating, said link being optimized to minimize cross talk by one of

• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

A multichannel data communication link for transmitting data from a transmitter to a remote receiver, said link comprising means for conditioning the signal from the transmitter, said means for conditioning being connected electrically to the transmitter, laser diode means for converting the signals output from the signal conditioning means, said laser diode means being connected to the signal conditioning means via one optical fiber per channel, wavelength division multiplexing means, at the transmitter, for multiplexing the outputs of the laser diode means and connected to the laser diode means via one optical fiber per channel, wavelength division demultiplexing means connected to the output of the multiplexing means via an optical fiber, detector means connected to the demultiplexing means via one optical fiber per channel, signal conditioning means connected electrically to the outputs of the detector means, and receiver means electrically connected to the outputs of the signal conditioning means, said multiplexing and demultiplexing means having paraxially arranged transmission optics and a littrow broad band uniform reflection grating wherein the optical fibers connecting the laser diode means and the multiplexing means are of smaller diameter than the optical fiber connecting the multiplexing and demultiplexing means, and the optical fibers connecting the demultiplexing means and the detectors are of larger diameter than the said fibers and fiber, said link being optimized to minimize cross talk by one of

• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

A multichannel video link for linking the central processing unit of a real time market data computer to a plurality of data feed monitors and keyboards, said link comprising a transmitting module which fits into the electronics rack of the computer, a receiving module which fits into the electronics rack of a remote receiver to which is connected the plurality of data feed monitors, and optical path means connecting the transmitting module to the receiving module, said transmitting module comprising a laser diode source for each channel in the system operating in the single window range of 750-850 nm, a wavelength division multiplexer connected to each of the laser diode outputs and having fibers, a uniform broadband reflection littrow grating, and paraxial transmission optics;

• said optical path means comprising a standard multimode fiber;
• the receiving module comprising a wavelength division demultiplexer (WDDM) connected to the optical path means and having fibers, a uniform broadband reflection littrow grating, paraxial transmission optics, and an output for each channel, and photodetector means connected to each output of the WDDM, the outputs of the photodetector means connected to the data feed monitors, said link being optimized to minimize cross talk by one of
• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

A multichannel video link for linking the central processing unit of a real time market data computer to a plurality of data feed monitors and keyboards, said link comprising a transmitting module which fits into the electronics rack of the computer, a receiving module which fits into the electronics rack of a remote receiver to which is connected the plurality of data feed monitors, and optical path means connecting the transmitting module to the receiving module, said transmitting module comprising a laser diode source for each channel in the system operating in the single window range of 750-850 nm, a wavelength division multiplexer connected to each of the laser diode outputs and having a uniform broadband reflection littrow grating and paraxial transmission optics to provide channel separation of less than 50 nm;

• said optical path means comprising a standard multimode fiber;
• the receiving module comprising a wavelength division demultiplexer (WDDM) connected to the optical path means and having a uniform broadband reflection littrow grating and paraxial transmission optics to provide channel separation of less than 50 nm, and an output for each channel, and photodetector means connected to each output of the WDDM, the outputs of the photodetector means connected to the data feed monitors, wherein the wavelength division demultiplexer is optimized in accordance with the following equation ##EQU63## where b is the core to core distance between fibers, d is the core diameter, and k is ##EQU64## wherein d.lambda.0 is wavelength shift.

A multichannel video link for linking the central processing unit of a real time market data computer to a plurality of data feed monitors and keyboards, said link comprising a transmitting module which fits into the electronics rack of the computer, a receiving module which fits into the electronics rack of a remote receiver to which is connected the plurality of data feed monitors, and optical path means connecting the transmitting module to the receiving module, said transmitting module comprising an LED for each channel in the system operating in the single window range of 750-850 nm, a wavelength division multiplexer connected to each of the laser diode outputs having a uniform broadband reflection littrow grating and paraxial transmission optics to provide channel separation of less than 50 nm;

• said optical path means comprising a standard multimode fiber;
• the receiving module comprising a wavelength division demultiplexer (WDDM) connected to the optical path means and having a uniform broadband reflection littrow grating and paraxial transmission optics to provide channel separation of less than 50 nm, and an output for each channel, and photodetector means connected to each output of the WDDM, the outputs of the photodetector means connected to the data feed monitors, wherein ##EQU65## where b is the core to core distance between fibers, d is the fiber core diameter, and k'=.delta..lambda.,.DELTA..lambda., .delta..lambda. is ELED linewidth, and .DELTA..lambda. is wavelength separation.

An integrated services digital network (ISDN) comprising a first plurality of connected computer workstations, a second plurality of connected computer workstations, a multiplexing link having electrical inputs from the first plurality, and video and voice signal inputs and an optical output;

• and a demultiplexing link having an optical input connected via a single fiber to the optical output of the multiplexing link, and an electrical output to the second plurality and video and voice signal outputs;
• said multiplexing link comprising a laser diode source;
• wavelength division multiplexer means coupled to said source and having paraxial optics including first fibers, lens means, and a littrow reflection grating paraxially aligned with said first fibers;
• said demultiplexing link comprising wavelength demultiplexing means having paraxial optics including second fibers, lens means, and a littrow reflection grating paraxially aligned with said second fibers, said link being optimized to minimize cross talk by one of
• (A) setting a b/d ratio for said first and second fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying, for said first and second fibers, the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

A local area networking (LAN) system comprising an engine workstation connected to wavelength division demultiplexing means (WDDM);

• said WDDM connected optically via a single transmission fiber to remote wavelength division demultiplexing means (WDDM) connected to a remote workstation;
• said engine workstation transmitting signals to and receiving signals from said remote workstation over said single transmission fiber, said WDDM and remote WDDM having fibers, a littrow reflection grating, and lens means paraxially aligned with said transmission fiber, said link being optimized to minimize cross talk by one of
• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.

A multichannel data communication link comprising a first wavelength division multiplexing bidirectional coupler, a second wavelength division multiplexing bidirectional coupler, first and second transmitters including a laser diode source, and first and second receivers, the first transmitter inputting a first wavelength light wave into the first coupler, the second transmitter inputting a second wavelength light wave into the second coupler, the first coupler inputting the first wavelength light wave into the second coupler and the second coupler inputting the second wavelength light wave into the first coupler, the second coupler outputting the first wavelength light wave into the second receiver and the first coupler outputting the second wavelength light wave into the first receiver, said couplers having fibers, a littrow reflection grating, and a lens paraxially aligned, said link being optimized to minimize cross talk by one of

• (A) setting a b/d ratio for said fibers so as not to be smaller than (1/1-k), where b is the core to core distance between fibers, d is the diameter of the fiber cores, and k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and
• (B) satisfying the equation:
• k<1-d/b, where k=d.lambda./.DELTA..lambda., where d.lambda. is the maximum acceptable wavelength shift of said laser diode source and .DELTA..lambda. is wavelength separation, and where d is the diameter of the fiber cores and b is the core to core distance between fibers.