Abstract:
An optical switching apparatus comprising a housing with first and second optical ports on the housing for receiving optical connectors, wherein the first and second optical ports are optically connected in a first state. A third and fourth optical port for receiving optical connectors are provided in the housing for which are optically connected in a first state. An optical switch within the housing optically connects the first optical port to the third optical port and optically connects that the second optical port to the fourth optical port in a second state, wherein the optical switch is mechanically actuated due to insertion of an optical connector in at least one of the first and second optical ports. A sliding cam against a ball bearing accurately re-aligns two fiber optic arrays to switch from a first state to a second state.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to patch panels, and more particularly, to optical switching technology. 
         [0003]    2. Description of Related Art 
         [0004]    Conventional designs for normal through patch panels typically require external power to operate the switching functions, proprietary connector interfaces or are designed for a limited number of connector configurations and transmission channels. Additionally, conventional patch panel designs or normal through patch panel designs are large and heavy mechanisms. 
         [0005]    Accordingly, there is a need for a normal through mechanical optical patch panel that is compact, lightweight, passive, uses industry standard connector interfaces and is capable of accommodating multiple optical connector configurations and high density optical channel management. 
       SUMMARY OF THE INVENTION 
       [0006]    In accordance with the present invention, a passive optical switch is provided that is mechanically actuated by the insertion of industry standard optical duplex or multi-fiber connector into its ports. The reduction in use of patch cables greatly reduces the volume and weight of cabling required in an installation important in mobile network applications. 
         [0007]    Optical normal through technology enables a network designer or user, typically in a broadcast or military networking applications to significantly reduce the complexity and number of the optical patch cable requirements and associated patching hardware by allowing “normal” patch routings to be set up without the typical use of patch cables on the front of the panel. All of the standard routings can be pre-configured with minimal space use on the rear of a high density patch-panel. Very similar in functionality to existing equivalent copper RF and RJ-45 type “normal-through” adaptors, the optical normal through also allows, when needed, for conventional patch cables to be plugged into the patch panel, to enable the automatic routing in and out of signals for temporary fiber channel routing or networks changes. 
         [0008]    The present invention further provides connection ports to the device which are for industry standard low insertion loss duplex connectors like LC, and is capable of providing normal though duplex channel functionality for both single mode and multimode fiber channels. The optical patch panel is mechanically operated without the necessity of external power and provides for normal through optical connectivity without the use of excessive patch cables. The space envelop required by the present invention is very small and similar to conventional copper counterparts. The switching functionally provided by the present invention is low loss in both the normal through or switched out modes. 
         [0009]    Accordingly, an optical switching apparatus is provided comprising a housing with first and second optical ports on the housing for receiving optical connectors, wherein the first and second optical ports are optically connected in a first state. A third and fourth optical port for receiving optical connectors are provided in the housing which are optically connected in a first state. An optical switch within the housing optically connects the first optical port to the third optical port, and optically connects that the second optical port to the fourth optical port in a second state, wherein the optical switch is mechanically actuated responsive to insertion of an optical connector in at least one of the first and second optical ports. A sliding cam against a ball bearing accurately re-aligns two fiber optic arrays to switch from a first state to a second state. 
         [0010]    The foregoing has outlined, rather broadly, the preferred features of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention and that such other structures do not depart from the spirit and scope of the invention in its broadest form. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1   a  is a top view of an optical normal through configured in accordance with the present invention; 
           [0012]      FIG. 1   b  a side view of the optical normal shown in  FIG. 1   a;    
           [0013]      FIG. 1   c  is a bottom view of the optical normal through shown in  FIGS. 1   a  and  1   b;    
           [0014]      FIG. 1   d  is an end view of the optical normal through shown  FIGS. 1   a ,  1   b  and  1   c;    
           [0015]      FIG. 2  is a top view of the optical normal through shown in  FIG. 1   a  with the top cover removed showing the internal components; 
           [0016]      FIG. 2   a  is an enlarged view of an optical switcher located within the optical normal through shown in  FIGS. 1   a - 1   d  and  FIG. 2 ; 
           [0017]      FIG. 3   a  is a bottom view of an optical normal through configured in accordance with the present invention; 
           [0018]      FIG. 3   b  is an end view of multiple optical normal through as shown in  FIG. 3   a  mounted immediately adjacent to each other to form an optical patch panel; 
           [0019]      FIG. 3   c  is a side view of the stack of multiple optical normal throughs shown in  FIG. 3   b;    
           [0020]      FIG. 4   a  is a schematic diagram of an optical normal through configured in accordance with the present invention in the unswitched or first state position; 
           [0021]      FIG. 4   b  is a schematic diagram of the optical normal through shown in  FIG. 2   b  in the switched or second state position; 
           [0022]      FIG. 5   a  is a schematic diagram of a double phase translation optical normal through configured in accordance with the present invention in a non-switched or first state position; 
           [0023]      FIG. 5   b  is a schematic diagram of the optical normal through shown in  FIG. 5   a  in a switched or second state position; 
           [0024]      FIG. 5   c  is a schematic diagram of a single phase translation optical normal through configured in accordance with the present invention in a non-switched or first state position; 
           [0025]      FIG. 5   d  is a schematic diagram of the optical normal through shown in  FIG. 5   c  is a switched or second state position; 
           [0026]      FIG. 5   e  is a schematic diagram of an alternative single phase translation optical normal through configured in accordance with the present invention in a non-switched or first state position; 
           [0027]      FIG. 5   f  is a schematic diagram of the optical normal through shown in  FIG. 5   e  is a switched or second state position; 
           [0028]      FIG. 6  illustrates two fiber optic arrays of an optical switch configured in accordance with the present invention in the second state or switched position and illustrates the use of an industry standard array ferrule like an MT array ferrule for the switching mechanism, and the phased translation of the fiber arrays relative to one another; and 
           [0029]      FIG. 7  illustrates a process of the present invention for manufacturing one embodiment of the two fiber optic arrays of the optical switch using V-array fiber mounting plates of silica or Pyrex® or other precisely machined material combinations for the fiber array switching interfaces shown in  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0030]    Referring now to the drawings,  FIG. 1  illustrates a top view of an optical normal through  10  configured in accordance with the present invention. The housing  12  can be constructed of plastic or metal. A top plate  11  is preferably secured to the housing by screws  13 . 
         [0031]    Ports  22 , 23  on the housing  12  are configured to receive optical connectors  14 , 15  having an industry standard LC configuration. Ports  21 , 22  on the housing  12  are configured to receive optical connectors  16 ,  17 ,  18 ,  19  having an industry standard LC configuration. Of course, other optical connector configurations can be used on the optical normal through  10  including connectors with more fibers than a duplex configuration. 
         [0032]      FIG. 1   b  is side view of the optical normal though  10  shown in  FIG. 1   a .  FIG. 1   b  shows the housing  12 , optical ports  21 , 23 , and optical connectors  15 , 19 . 
         [0033]      FIG. 1   c  is a bottom view of the housing  12  shown in  FIGS. 1   a  and  1   b .  FIG. 2   c  shows the housing  12 , ports  20 ,  21 ,  22 ,  23  and optical connectors  14 ,  15 ,  16 ,  17 ,  18 ,  19 . 
         [0034]      FIG. 1   d  is an end view of the optical normal through  10  shown in  FIGS. 1   a ,  1   b ,  1   c .  FIG. 1   d  shows the LC optical connectors  14 , 15 . 
         [0035]      FIG. 2  is illustrates the optical normal through shown in  FIGS. 1   a - 1   d  with the top cover  11  removed so an optical switch  44  and related components contained therein can be illustrated. The optical switch  44  is shown providing an optical connection between the optical ports  20 ,  21 ,  22 ,  23 . Optical fibers  45  from optical ports  20 , 21  are shown as extensions of fiber ribbon cable  36  which enters the optical switch  44 . Similarly, fiber ribbon cable  34  optically connects optical ports  23 , 23  to the optical switch  44 . A plate  31 , secured by screws  49 , covers optical fibers that assist in rerouting of optical connections provided by the optical switch  44 . These optical fiber connections are shown schematically in  FIGS. 5   a - 5   f.    
         [0036]    In accordance with the present invention, two fiber arrays in opposing MT ferrules or opposing fiber V arrays  30 , 32  of optical fibers positioned within the same geometric plane and in direct slidable contact, move laterally to switch optical channels between the two fiber arrays  30 , 32 . A slidable cam  27  including a notch  29  ( FIG. 2   a ) slides against a ball bearing  25  or bearing wall to accurately slide a first fiber MT ferrule or V-groove array (FVA)  30  laterally against a second MT ferrule or fiber V-groove array (FVA)  32  at a juncture  33  wherein the first and second MT ferrules or FVAs are in direct slidable contact. In accordance with a further aspect of the present invention, an index matching gel is applied to the MT ferrule arrays or FVAs at the juncture  33  to further improve optical communication at the juncture  33  and lubrication of the slidable surfaces. 
         [0037]    A Y-bar  28  is slidably connected to the optical ports  22 , 23  so as to be actuated and slide toward the juncture  33  when an optical connector is inserted into either port  22  or  23 . A spring  51  provides small resistance on the Y-bar away from the juncture  33 , until the Y-bar is move toward the juncture  33  in response to an optical connector being inserted or connected to optical port  22  or  23 . Pins  41 ,  42 ,  43  are located in elongated apertures within the Y-bar to guide the Y-bar while transitioning between different switching positions. 
         [0038]      FIG. 2   a  illustrates the Y-bar  28  with the cover plate  31  removed. Also shown is the Y-bar bar connected to the slidable cam  27 . The cam has a notch  29  on the side of the cam  27  that rides against the ball bearing  25 . The Illustrated cam  27  is a flat bar with a notch  29 , but could be a round bar with a notch or other configurations. Similarly, the ball bearing  25  could be any bearing surface in other embodiments. Spring bars  24  and  26  provide a force to keep the cam  27  and ball bearing  25  adjacent to each other as the cam  27  slides back and forth between switching positions. As illustrated in  FIG. 2   a , the movement of the cam  27  to the right causes the ball bearing  25  to move the first fiber array  30  away from the cam  27  to move into the second state or switched position in response to an optical connector being inputted into optical port  22  or  23 . Of course, the notch  29  in the cam  27  could be repositioned so the notch  29  is located further left on the cam  27 , and inputting an optical connector causes the ball bearing  25  to move into the notch  29 , and move the first MT ferrule or FVA  30  towards, instead of away from, the cam  27 . 
         [0039]      FIG. 3   a  illustrates a top view of an optical normal through  60  configured in accordance with the present invention. LC optical connectors  61  are shown connected to the front panel of the optical normal through  60 , and LC optical connectors  63  are shown connected to the rear of the optical normal through. 
         [0040]    Of course, ports of the optical normal through can be configured to connect with numerous types of optical connectors. For example, all optical ports could be duplex LC, duplex SC, MT-RJ or any other duplex connector. All the optical ports could be MTs greater than 2 fiber duplex, such as 8-way connectors, but then the optical switch would need to have more than 8 opposing fibers in each MT ferrule or FVA to switch two duplex connectors. 
         [0041]      FIG. 3   b  illustrates a plurality of the optical normal throughs  60  stacked adjacent to each other to form a “patch panel.”  FIG. 3   b  is a front view of the LC connectors  61  on the “front” of the “patch panel” created by stacking multiple optical normal throughs  60  adjacent to each other. 
         [0042]      FIG. 3   c  is a side view of the stacked optical normal throughs  60  shown in  FIG. 3   b.    
         [0043]      FIG. 4   a  is a schematic diagram of an optical normal through  70  configured in accordance with the present invention. Optical ports  72 , 74  on the input side are shown by arrow  79  as being optically connected together. Arrow  80  illustrates optical ports  76 , 78  on the back as being optically connected together. FVA  71  and FVA  75  are shown in direct slidable contact with each other at juncture  73  in the unswitched or normal or first state position. 
         [0044]      FIG. 4   b  is a schematic diagram of the optical normal through  70  in the switched or second state or position  2 . Arrow  81  indicates that optical ports  72  and  76  are optically connected in the switched position. Arrow  82  indicates that optical ports  74  and  78  are optically connected in the second state or switched position. Furthermore, the MT ferrule arrays or FVAs  71  and  75  are in the switched or second state position. 
         [0045]      FIGS. 5   a  illustrates a schematic diagram of an optical normal through  90  configured in accordance with the present invention in the normal or first state position for a 500 um optical connection using double phase switching. FVA 1  and FVA 2  are positioned so that all the channels are aligned in the first state. In the first state, optical ports LC IN A and LC IN B are optically connected, and optical ports LC OUT A and LC OUT B are optically connected. 
         [0046]      FIG. 5   b  illustrates the schematic diagram  90  in the second state position wherein the FVA 1  and FVA 2  have moved by two channels or two phases. In the second state optical ports LC IN A and LC OUT A are optically connected, and optical ports LC IN B and LC OUT B are optically connected. 
         [0047]      FIGS. 5   c  illustrates a schematic diagram of an optical normal through  92  configured in accordance with the present invention in the normal or first state position for a 250 um optical connection using single phase switching. FVA 1  and FVA 2  are positioned so that all the channels are aligned in the first state. In the first state, optical ports LC IN A and LC IN B are optically connected, and optical ports LC OUT A and LC OUT B are optically connected. 
         [0048]      FIG. 5   d  illustrates the schematic diagram  92  in the second state position wherein the FVA 1  and FVA 2  have moved by one channel or one phase. In the second state optical ports LC IN A and LC OUT A are optically connected, and optical ports LC IN B and LC OUT B are optically connected. 
         [0049]      FIGS. 5   e  illustrates a schematic diagram of an optical normal through  94  configured in accordance with the present invention in the normal or first state position for a 250 um optical connection using an alternative single phase switch. FVA 1  and FVA 2  are positioned so that all the channels are aligned in the first state. In the first state, optical ports LC IN A and LC IN B are optically connected, and optical ports LC OUT A and LC OUT B are optically connected. 
         [0050]      FIG. 5   f  illustrates the schematic diagram  92  in the second state position wherein the FVA 1  and FVA 2  have moved by one channel or one phase. In the second state optical ports LC IN A and LC OUT A are optically connected, and optical ports LC IN B and LC OUT B are optically connected. 
         [0051]      FIG. 6  illustrates an enlarged view of an MT ferrule array  102  and an MT ferrule array  104  configured in accordance with the present invention. An array of optical fibers  106  within MT ferrule array  102  and an array of optical fibers  108  in MT ferrule array  104  are precisely aligned within the same dimensional plane at a juncture  110 . Apertures  112  passing through both MT ferrule arrays  102 , 104  can be used to initially align the arrays of optical fibers  106 , 108 . Switching states or positions is achieved by sliding the optical fiber arrays  106 , 108  in the MT ferrule arrays  102 , 104  laterally at the juncture  110  while keeping the arrays  106 , 108  within the same dimensional plane. An index matching get can be applied at the juncture  110  to facilitate optical connectivity at the junction  110  and lubrication. 
         [0052]      FIG. 7  illustrates a method for precisely manufacturing two FVA arrays aligned in the same dimensional plane. A single block or package array  120  of optical fibers is provided as shown in step  120 . The package array can be constructed out of silica or Pyrex®, or other known technique for manufacturing FVAs. The single block array is then precisely cut in the mid-section to form a juncture  121  as shown by step  122 . Two FVAs  124  and  126  are then produced having a “match pair” of optic fiber arrays precisely in the same dimensional plane. 
         [0053]    While specific embodiments have been shown and described to point out fundamental and novel features of the invention as applied to the preferred embodiments, it will be understood that various omissions and substitutions and changes of the form and details of the apparatus illustrated and in the operation may be done by those skilled in the art, without departing from the spirit of the invention.