Abstract:
An optical transceiver system includes an optical transceiver module configured to be locked to cage in a host electronic equipment and a key configured to remove the optical transceiver module from the cage, wherein the key comprises two fingers configured to be inserted into the cage and unlock optical transceiver module from the cage.

Description:
TECHNICAL FIELD 
     This disclosure relates to optical transceiver modules. 
     RELATED PATENT APPLICATIONS 
     The present patent application is related to commonly assigned and concurrently filed US design patent application, entitled “REMOVABLE KEY FOR OPTICAL TRANSCEIVER”, the disclosure of which is incorporated herein by reference. 
     BACKGROUND 
     Fiber optic lines have been increasingly used to handle the increased data transmission volume over the data network. Fiber optic lines and the associated fiber optic signals typically require transceivers to convert optical light pulse signals to electronic signals that can be processed by computers. Modern optical transceivers have been modularized with standard physical sizes, and optical and electrical interfaces, which are specified by various agreements. One such standard agreement is 10 Gigabit Small Form Factor Pluggable modules (XFP). An XFP transceiver module refers to an optical transceiver that complies with XFP specifications such as outer envelope size, internal electrical specifications, optical connector ports, and electrical interface. 
     A conventional optical transceiver can include a built-in unlocking mechanism to allow the optical transceiver to be un-locked and unplugged from a cage in the host equipment the optical transceiver is connected to. For example, referring to  FIG. 1 , a conventional optical transceiver module  100 , which may be compatible with XFP standard, can include a base portion  110 , a cover  120 , an optical interface  130 , an electrical interface  140 , with edge connectors, a locking gap  160 , an unlocking lever  180 , and a pair of unlocking fingers  190 . The unlocking lever  180  can be lifted outward from the optical transceiver module  100 , which causes the unlocking fingers  190  to move inward to push the locking tabs of the cage that the optical transceiver module  100  resides in, thus unlocking the optical transceiver module  100  from the cage. A disadvantage of the conventional optical transceiver module  100  is that it does not provide security. The optical transceiver module transceiver can be unplugged from the cage during operations. 
     SUMMARY 
     In a general aspect, the present invention relates to an optical transceiver system including an optical transceiver module that can be locked to cage in a host electronic equipment and a key configured to remove the optical transceiver module from the cage, wherein the key includes two fingers configured to be inserted into the cage and unlock optical transceiver module from the cage. 
     In another general aspect, the present invention relates to a removable key for an optical transceiver module including two fingers configured to be inserted into a cage in which the optical transceiver module is plugged, wherein the two fingers are configured to unlock optical transceiver module from the cage; and a locking mechanism to allow the key to be locked to the optical transceiver module, thereby allowing the optical transceiver module to unplugged from the cage by pulling the key. 
     In another general aspect, the present invention relates to a method for locking and unlocking an optical transceiver module. The method includes inserting two fingers of a removable key into a cage in which the optical transceiver module is plugged; unlocking optical transceiver module from the cage; locking the key to the optical transceiver module; and pulling the key to unplug the optical transceiver module from the cage. 
     Implementations of the system may include one or more of the following. The key can include a locking mechanism to allow the key to be locked to the optical transceiver module. The locking mechanism can include a locking pin that is configured to be locked into a locking recess in the optical transceiver module. The key can include a releasing mechanism to allow the key to be disconnected from the optical transceiver module. The releasing mechanism can include a pivot block that is moved upward from a normal position to move the locking pin out of the locking recess. The key can include a spring configured to return the pivot block to the normal position after the locking pin is moved out of the locking recess. The optical transceiver module can include two tracks to receive the two fingers, wherein the two tracks are on two opposite surfaces of the optical transceiver module. The two figures can be substantially parallel to each other. 
     Embodiments may include one or more of the following advantages. The security of the optical communication is improved. The disclosed optical transceiver is locked into a cage during operation and can be unlocked only by a key specially designed for the optical transceiver. The key can be accessible to only authorized personnel. The key also include features that allow it to be easily carried by the authorized personnel. Another advantage of the disclosed system is that the optical transceiver can be simplified by removing the unlocking mechanism that is included in some conventional optical transceiver modules. Manufacturing complexity and cost for the optical transceiver are thus reduces. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a conventional XFP optical transceiver module with a built-in unlocking mechanism. 
         FIG. 2  is a perspective view of an optical transceiver and a key for unlocking the optical transceiver. 
         FIG. 3  is a perspective view of the optical transceiver of  FIG. 2  and the key in a position that is locked to the optical transceiver. 
         FIG. 4  is top view and an enlarged view of the optical transceiver and the key when the key is in a position locked to the optical transceiver. 
         FIG. 5  is a side view and an enlarged view of the optical transceiver and the key when the key is in a position locked to the optical transceiver. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 2 , an optical transceiver  200  is comprised of a base portion  210 , a cover  220 , an optical interface  230 , an electrical interface  240 , one or more tracks  250 , two locking gaps  260  (one of the two gaps is on the other side of the optical transceiver  200  and is thus not visible in  FIG. 2 ), and a lock pin  270 . In contrary to a conventional optical transceiver module, the optical transceiver  200  does not include a built-in unlocking mechanism. A key  300  is provided to unlock the optical transceiver  200  from the cage. The key  300  includes unlocking fingers  320 , a pivot block  330 , a pivot arm  340 , a spring  350 , a press-button  360 , a locking recess  370 , a bulge  380 , and a pothook  390 . The optical transceiver  200  can be inserted into the cage and locked into the cage, when the pins in the cage are locked to the locking gaps  260 . The optical transceiver  200  can be compatible with the XFP specifications. 
     To unlock the optical transceiver  200 , the key  300  can be inserted into the case. The unlocking fingers  320  can be pushed along tracks  250  to push the pins in the cage outward, therefore releasing the locking of the optical transceiver  200  by the cage. At the same time, the lock pin  270  of the optical transceiver  200  can be locked to the locking recess  370  of the key  300  to connect the key  300  to the optical transceiver  200 . Now that the optical transceiver  200  in unlocked from the cage and connected to the key  300 , the optical transceiver  200  can be unplugged from the cage by pulling key  300 . 
     Once the optical transceiver  200  is outside the cage, it can be disconnected from the key  300  by pressing the press-button  360 . The pivot block  330  is moved upward, thus releasing the locking pin  270  of the optical transceiver  200  from the locking recess  370  of the key  300 . The pivot block  330  returns to its normal state by the spring  350  once the press button  360  is released, making the key  300  ready for the next unlocking operation. 
     Details about the optical transceiver are disclosed in commonly assigned U.S. patent application Ser. No. 10/741,805, titled “Bi-directional optical transceiver module having automatic-restoring unlocking mechanism”, filed on Dec. 19, 2003, U.S. patent application Ser. No. 10/815,326, titled “Small form factor pluggable optical transceiver module having automatic-restoring unlocking mechanism and mechanism for locating optical transceiver components”, filed on Apr. 1, 2003, and U.S. patent application Ser. No. 10/850,216, titled “Optical Transceiver module having improved printed circuit board”, filed on May 20, 2004. The disclosures of these related applications are incorporated herein by reference. 
     One advantage of the disclosed system is improvement of security when an optical transceiver is used in operation. The disclosed key can be accessible to only authorized personnel. The optical transceiver can thus not be easily removed. The security of the optical transceiver during operation is thus improved. Another advantage of the disclosed system is that a lock pin is provided to lock the key with the optical transceiver. Yet another advantage of the disclosed system is that the optical transceiver can be simplified by removing the unlocking mechanism in some conventional optical transceiver modules. 
     It is understood that disclosed key and the transceiver module may be suitable for different optical transceiver standards such as the XFP format. The disclosed system can be compatible with different configurations for the key and the optical transceiver as well as different methods of locking and unlocking the optical transceiver in and out of the cage.