Optical waveguides – With optical coupler – Input/output coupler
Reexamination Certificate
1999-09-17
2001-08-07
Spyrou, Cassandra (Department: 2872)
Optical waveguides
With optical coupler
Input/output coupler
C385S031000, C385S033000, C359S199200, C359S199200
Reexamination Certificate
active
06272266
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to couplers for fiber optic cables and, more particularly, to methods and apparatus for transmitting an inserted optical signal into an optical coupler and transmitting an extracted optical signal from the optical coupler so that the extracted optical signal does not contain any aspect of the inserted optical signal.
BACKGROUND OF THE INVENTION
It is well known to use fiber optic systems to carry optical signals. Optical signals can be characterized as including optical energy, and optical signals may additionally include information, such as data, audio or video information.
Fiber optic systems have a number of features that make them superior, in some applications, to systems that use traditional copper cables, or the like. For example, fiber optic systems can have a much larger information-carrying capacity and are not subject to electrical interference. In addition, signals transmitted over long-distance optic fibers need less amplification tham do signals transmitted over copper cables of equal length.
In a fiber optic system, it is typical for two optic fibers to be fused in an end-to-end arrangement to provided a continuous length of optic fiber. It is also common for optic fibers to be fused in a side-by-side arrangement, in which an elongate section of one optic fiber is fused to an elongate section of another optic fiber so that optical signals are transferred between the fused fibers. Such a side-by-side fused optical interface, which can be characterized as a passive fusion coupler, allows for good transfer of optical signals between the fused optic fibers, but provides no control over the direction of transfer and little or no control over the amount of optical energy transferred. Whereas it may be desired for optical signals to be transferred only from a first of the fused optic fibers to a second of the fused optic fibers in a passive fusion coupler, optical signals may also be transferred in the opposite, undesired direction, i.e., from the second optic fiber to the first optic fiber. Thus, passive fusion couplers are disadvantageous in some applications, such as where it is desired to use a single coupler to transmit optical signals via an optical path and receive optical signals from the same path while keeping any of the transmitted signals separate from the received signals.
It is also common for fiber optic systems to include powered couplers. A powered coupler includes an optical receiver, such as a photo detector, that receives optical signals, converts the optical signals into electronic data, and supplies the electronic data to another powered coupler that transmits optical signals. Whereas powered couplers can detect information on one optic fiber and transmit the information on another optic fiber, some aspects of the original optical signals may be lost in the transfer, such as the energy level, frequency or amplitude of the original optical signal, which can be disadvantageous in some applications.
SUMMARY OF THE INVENTION
The present invention solves the above problems, and other problems, by providing methods and apparatus for facilitating the transmission of inserted optical signals into, and the reception of extracted optical signals from, an optic device through which initial optical signals can be propagating irrespective of the inserted optical signals and the extracted optical signals, and in which the extracted optical signals do not contain any aspect of the inserted optical signals.
In accordance with one aspect to the present invention, the initial optical signals propagate in a downstream direction through the optic device, and both the transmission of the inserted optical signals into the optic device and the reception of the extracted optical signals from the optic device are carried out at what can be characterized as a common, planar optical interface that is perpendicular to the direction of propagation of the initial optical signals. The transmissions are carried out so that the extracted optical signals contain solely the information contained by the initial optical signals, and the extracted optical signals contains less optical energy than the initial optical signals.
More specifically, the initial optical signals Lre transmitted into an upstream end of the optic device so that the initial optical signals propagate toward a downstream end of the optic device, the inserted optical signals are transmitted into the optic device at the optical interface, the extracted optical signals are received from the optic device at the optical interface, and composite optical signals propagate downstream through the optic device from the optical interface and are transmitted from the downstream end of the optic device. The extracted optical signals consist solely of the information of the initial optical signals and an extracted portion of the optical energy of the initial optical signals. In contrast, the composite optical signals transmitted from the downstream end of the optic device include the information of the initial optical signals, the unextracted portion of the optical energy of the initial optical signals, and all of the inserted optical signals.
In accordance with one embodiment of the present invention, methods of the present invention are carried out through the use of a plurality of gradient index (GRIN) lenses, or the like that are assembled to form an optic device having opposed upstream and downstream ends. The above-discussed optic device includes a primary transmitting GRIN lens having opposite first and second ends, and is operative to collimate optical signals propagating therethrough. The collimated signals are emitted via the first end of the primary transmitting GRIN lens, while the second end of the primary transmitting GRIN lens serves as the upstream end of the optic device. The optic device further includes a primary receiving GRIN lens having opposite first and second ends, and operative to focus optical signals propagating therethrough and emitted via the second end thereof. The first end of the primary receiving GRIN lens is optically connected to the first end of the primary transmitting GRIN lens at the optical interface, such that the primary transmitting GRIN lens is operative for transmitting collimated optical signals to the primary receiving GRIN lens. The ;econd end of the primary receiving GRIN lens serves as the downstream end of the optic device.
A secondary transmitting GRIN lens has opposite first and second ends and is operative to collimate optical signals propagating therethrough and emitted via the first end thereof. The first end of the secondary transmitting GRIN lens is optically connected to the first end of the primary receiving GRIN lens at the optical interface, such that the secondary transmitting GRIN lens is operative for transmitting collimated optical signals to the primary receiving GRIN lens. A secondary receiving GRIN lens also has opposite first and second ends and is operative to focus optical signals propagating therethrough and emitted via the second end thereof. The first end of the secondary receiving GRIN lens is optically connected to the first end of the primary transmitting GRIN lens at the optical interface, such that the primary transmitting GRIN lens is operative for transmitting collimated optical signals to the secondary GRIN lens.
The initial optical signals are introduced into the second end of the primary transmitting GRIN lens. The information of the initial optical signals and the unextracted portion of the optical energy of the initial optical signals are transmitted from the first end of the primary transmitting GRIN lens to the first end of the primary receiving GRIN lens. The information of the initial optical signals and the extracted portion of the optical energy of the initial optical signals are transmitted from the first end of the primary transmitting GRIN lens to the first end of the secondary receiving GRIN lens. The inserted optical signals are introduced into the second end of the
Alston & Bird LLP
Boutsikaris Leo
Spyrou Cassandra
The Boeing Company
LandOfFree
Multipath optical coupler and associated method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multipath optical coupler and associated method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multipath optical coupler and associated method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2453817