PATENT DOCUMENT

Publication Number: US-8562226-B2
Application Number: US-76225510-A
Country: US
Kind Code: B2

Title: Connectors and cables with an optical transmitter

Abstract:
Cable adapters and connectors receive electrical signals and output optical signals. A cable adapter can receive various data signals in multiple interface protocols at a first electrical connector and provide an optical signal at a second connector. The conversion of electrical signals to optical signals may be achieved at various locations in the cable adapter. A connector can include an optical transmitter for converting electrical signals into optical signals. Such a connector can be provided on an output end of a cable adapter to provide optical signals corresponding to electrical signals received at an input connector of the cable adapter.

Claims:
What is claimed is: 
     
       1. A male plug connector comprising:
 a housing configured to at least partially fit inside a corresponding optical female connector; 
 an optical transmitter within the housing, the optical transmitter configured to: 
 receive electrical signals; and 
 transmit optical signals corresponding to the received electrical signals, the optical signals to be received by the corresponding optical female connector; 
 a circuit board to which the optical transmitter is electrically connected, wherein the circuit board receives the electrical signals and conveys the electrical signals to the optical transmitter; and 
 a light guide extending from within the housing to outside of the housing, wherein the light guide is configured to receive the optical signals and to carry the optical signals to the corresponding optical female connector. 
 
     
     
       2. The male plug connector of  claim 1 , wherein the housing is a single piece of insulating material. 
     
     
       3. The male plug connector of  claim 1 , wherein the housing has approximately a same width and height along an entire length of the housing. 
     
     
       4. The male plug connector of  claim 1 , further comprising:
 a cover around the light guide; and 
 a locking member disposed through a slot opening in the housing, the locking member holding the cover such that the light guide is in alignment with the optical transmitter. 
 
     
     
       5. The male plug connector of  claim 4 , further comprising:
 one or more pins disposed through the housing in a same orientation as the locking member, the one or more pins located between the optical transmitter and a back end of the housing, 
 wherein the locking member and the one or more pins are bonded to the circuit board. 
 
     
     
       6. The male plug connector of  claim 1 , wherein the housing has an opening above the transmitter, and wherein the male plug connector further comprises:
 a lock piece disposed over the optical transmitter and at least partially filling the opening. 
 
     
     
       7. The male plug connector of  claim 6 , wherein the lock piece has a flat lower section that fits between a back of the optical transmitter and an inner wall of the housing. 
     
     
       8. A connector comprising:
 a housing configured to mate with a corresponding optical connector; 
 an active optical component within the housing, the active optical component between a front portion of the housing and a back portion of the housing, wherein the front portion is separated from the back portion by an opening in at least one wall of the housing; and 
 a locking piece fitted into the opening over the active optical component, wherein the lock piece locks with the front portion of the housing and with the back portion of the housing. 
 
     
     
       9. The connector of  claim 8 , wherein the active optical component is configured to receive electrical signals and transmit optical signals corresponding to the received electrical signals, the connector further comprising:
 a light guide assembly for carrying the optical signals from the active optical component to the corresponding optical connector. 
 
     
     
       10. The connector of  claim 9 , further comprising:
 a locking member that engages the light guide assembly, the locking member disposed in a slot in a same wall that the opening exists, wherein the locking member aligns the light guide with the active optical component. 
 
     
     
       11. The connector of  claim 10 , further comprising:
 a circuit board, wherein the circuit board has traces electrically coupled with terminals of the active optical component, and wherein the circuit board is bonded to posts of the locking member; and 
 one or more pins disposed through the back portion of the housing, wherein the one or more pins are bonded to the circuit board.

Description:
BACKGROUND 
     The present invention relates generally to connectors used to carry optical signals and in particular to the conversion of electrical signals to optical signals using connectors and cable adapters. 
     Optical cables can be used to convey data signals, in a similar way that electrical cables carry data signals. For example, a compact disc (CD) or a Digital Versatile Disc (DVD) player can output audio signals in the form of light, which are conveyed via an optical cable. Normal optical audio cables are purely optical. That is, they require an optical connector at both ends and an optical fiber throughout the length of the cable. Such optical audio cables are passive in that they receive light and transmit the light. 
     Optical cables can have certain advantages over electrical cables, but also can have disadvantages. For example, the optical cables can malfunction if they are bent. Also, an optical cable typically only receives a single pulse of light at a time. Thus, the cables can only handle one interface protocol at a time, as there is only one pulse at a time per connector. Also, many devices may not have an optical output, while others may only have an optical input. Separate devices can be used to provide such a conversion, but such devices are relatively expensive and bulky. 
     Therefore, it is desirable to have cable adapters and connectors that can handle multiple protocols as well as provide signals to an optical interface. It is also desirable to have low cost cables that can provide a connection from an electrical output to an optical input while maintaining a small form factor. 
     BRIEF SUMMARY 
     Accordingly, embodiments of the present invention can provide cable adapters and connectors that receive electrical signals and output optical signals. For example, a cable adapter can receive multiple interface protocols at a first electrical connector and provide an optical signal at a second connector. The cable adapters and associated connectors of embodiments can provide any one or more of the advantages of accommodating multiple input protocols, multiple output connectors having various output protocols including optical protocols, and inexpensive manufacturing. In one embodiment, a connector includes an optical transmitter for converting electrical signals to optical signals. Such a connector can be provided on an output end of a cable adapter to provide optical signals corresponding to electrical signals received at an input connector of the cable adapter. 
     According to an embodiment, a male plug connector has an optical transmitter and a housing that fits into a corresponding optical female connector. The optical transmitter lies within the housing and is configured to convert electrical signals into optical signals to be received by the corresponding optical female connector. 
     According to another embodiment, a cable adapter has a first connector that receives electrical signals, a cable that carries the electrical signals, and a second connector that converts the electrical signals to optical signals. The second connector includes a housing configured to mate with a corresponding optical connector, an optical transmitter that converts electrical signals into optical signals, and a light guide that carries the optical signals to the corresponding optical connector. 
     According to another embodiment, a method of manufacturing a connector that receives electrical signals and outputs optical signals is provided. A light guide is inserted into a front opening of a housing of the connector. The housing has one or more outer walls that define the front opening. An active optical component is inserted through a top opening in at least one of the outer walls of the housing. The light guide is aligned with the active optical component. 
     According to another embodiment, a connector has a housing configured to mate with a corresponding optical connector, an active optical component, and a locking piece. The active optical component lies within the housing between a front portion of the housing and a back portion of the housing. The front portion is separated from the back portion by an opening in at least one wall of the housing. The active optical component is configured to receive electrical signals and transmit optical signals corresponding to the received electrical signals. The locking piece fits into the opening over the active optical component, and locks with the front portion of the housing and with the back portion of the housing. 
     A better understanding of the nature and advantages of the present invention may be gained with reference to the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a cable adapter that receives an electrical signal and outputs a corresponding optical signal according to embodiments of the present invention. 
         FIG. 2  shows a cable adapter that can receive multiple electrical signals and outputs corresponding electrical and optical signals according to embodiments of the present invention. 
         FIG. 3  is a flowchart illustrating an assembly process for making a connector having an active optical component according to embodiments of the present invention. 
         FIGS. 4A-4L  depict an optical connector at different stages of assembly process of  FIG. 3  according to embodiments of the present invention. 
         FIG. 5  shows a cross-sectional side view of male optical connector that includes an optical transmitter according to embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Certain embodiments can provide cable adapters and connectors that receive electrical signals and output optical signals. For example, a cable adapter can receive multiple interface protocols at a first electrical connector and provide an optical signal at a second connector. Thus, embodiments are not restricted to a single interface protocol, and can output optical signals. In one embodiment, a connector includes an optical transmitter for converting electrical signals to optical signals. Such a connector can be provided on an output end of a cable adapter to provide optical signals corresponding to electrical signals received at an input connector. 
     In some embodiments, using a connector with an optical transmitter allows conductive wires (e.g. made of copper) to be used throughout the length of a cable assembly. The conductive wires allow for more complicated splitter-style cable designs. In one embodiment, the connector is a male plug connector designed per the SPDIF (Sony/Philips Digital Interconnect Format)/Toslink structural specifications. Such a male plug connector can be mated with any standard stereo system with an optical audio input. 
       FIG. 1  shows a cable adapter  100  that receives an electrical signal and outputs a corresponding optical signal according to embodiments of the present invention. Cable adapter  100  receives electrical signals from sending device  180 , converts the electrical signals into optical signals, and provides the optical signals to receiving device  190 . Sending device  180  can provide one or more output electrical signals from electrical line(s)  186  through electrical contacts  184  of electrical connector  182 . The electrical connectors and electrical contacts described herein can have any suitable form factor and number of contacts. 
     Cable adapter  100  receives the one or more electrical signals at electrical contacts  105  of electrical connector  110 . As shown, the electrical connector  182  is a female receptacle connector that corresponds to the electrical connector  110 . The electrical signals are conveyed from electrical connector  110  to optical connector  120  via cable  130 . 
     Optical connector  120  provides optical signals through light guide  122  to optical connector  192  of the receiving device. Light guide  122  can be any suitable device that can carry light, e.g. a solid tube-like structure of glass or plastic or a hollow tube-like structure where the inner wall of the light guide reflect at least some light. As shown, the electrical connector  192  is a female receptacle connector that corresponds to the optical connector  120 . In other embodiments, light guide  122  may fit into an inner tube of a corresponding optical connector, where an outer surface of the corresponding optical connector can fit into an opening in a housing of optical connector  120 . Such embodiments provide for optical connectors that have both male and female aspects. 
     Receiving device  190  can use an optical to electrical converter  194  to convert the optical signals received from optical connector  120  into electrical signals on line  196 . Any type of signal (e.g. audio or video) could be conveyed with cable adapter  100 . Although, connectors  110  and  120  are shown as male connectors, female connectors also could be used. 
     In some embodiments, optical connector  120  includes an optical transmitter that converts electrical signals into optical signals. In these embodiments, cable  130  includes conductive wires (e.g. made of copper) that are electrically coupled with electrical contacts  105  and that carry electrical signals received at electrical contacts  105 . In one embodiment, cable  130  with conductive wires is flexible with a length of about one to three meters, and may have a plastic or rubberized coating. In one aspect, conductive wires of cable  130  can be bent without degrading the signal from electrical connector  110  to optical connector  120 . In another embodiment, optical connector  120  can include, instead of or in addition to the optical transmitter, an optical receiver that converts received optical signals into electrical signals, which are then transmitted to electrical connector  110  via cable  130 . The optical transmitter and optical receiver may be two separate units or one single unit (e.g., called a transceiver). 
     In other embodiments, electrical connector  110  includes an optical transmitter that converts electrical signals into optical signals. In these embodiments, cable  130  includes optical fiber for carrying optical signals from electrical connector  110  to optical connector  120 . In one aspect, electrical connector  110  can include (instead of or in addition to the optical transmitter) an optical receiver that converts received optical signals (i.e. received via cable  130 ) into electrical signals, which are then transmitted to electrical connector  182 . The optical transmitter and optical receiver may be two separate units or one single unit (e.g., called a transceiver). 
       FIG. 2  shows a cable adapter  200  that can receive multiple electrical signals and outputs corresponding electrical and optical signals according to embodiments of the present invention. Cable adapter  200  has the ability to receive electrical signals in multiple data formats, e.g. Universal Serial Bus (USB), High-Definition Multimedia Interface (HDMI), and digital audio signals. In one embodiment, electrical contacts  205  of electrical connector  210  have different contacts designated for each of the formats. 
     In some embodiments, electrical contacts  205  lie in a single row. The contacts designated for a particular format may be grouped together or they may lie in contact locations that are separated from each other by contacts for other purposes (e.g. ground, power, or for signals of other formats). 
     As an example, electrical connector  210  can have 30 contacts. Thus, cable  230  may have 30 conductive wires, one electrically coupled with each of the contacts. In various embodiments, four of the contacts can be used for USB, 19 contacts can be used for HDMI, and three wires for S/PDIF (2 for differential signal and one for power for transmitter). Electrical contacts  105  can be electrical contacts that can carry digital or electrical signals, e.g. as described in U.S. patent publication 2004/224638. 
     As electrical connector  210  can carry multiple data formats (interface protocols), it is desirable for cable adapter  200  to have a different second connector for each data format. Thus, cable adapter  200  has multiple connectors at opposite ends from electrical connector  210 . In one embodiment, cable adapter  200  includes an HDMI connector  260 , a USB connector  250 , and an optical connector  220  (e.g. a SPDIF or Toslink connector). 
     In one embodiment, a splitter  240  is used to separate the conductive wires of cable  230 . Splitter may simply be a housing for separating the wires into separate cables (each having its own covering), and does not contain electrical components. In another embodiment, cable  230  could have separate coating over different section of wires, and thus a splitter  240  is not used, as the separate sections could just be separated. Each opposite connector may be coupled with different conductive wires of cable  230 . For example, cable  236  may include conductive wires that are extensions of the conductive wires in cable  230  that carry the HDMI signals. Or, the wires in cable  236  may be electrically coupled to the conductive wires in cable  230  that carry the HDMI signals through another medium (e.g. a circuit board). 
     In one embodiment, splitter  240  can include an optical transmitter for converting electrical signals into optical signals. In this embodiment, cable  232  includes optical fiber for carrying optical signals from splitter  240  to optical connector  220 . Also, splitter  240  may have an output optical connector to which a connector of cable  232  could connect. Thus, cable  232  could be a separate optical cable that passively carries the optical signals from splitter  240  to a receiving device. 
     However, an optical cable can be hard to manufacture, particularly if there are also electrical wires. Such construction could be more costly as typically the wires (with signals destined to be converted to optical signals) would be cut and terminated at splitter  240 , and electrical devices added to splitter  240 . 
     In another embodiment, optical connector includes an optical transmitter for converting electrical signals (e.g., digital audio or video signals) into optical signals. In this embodiment, cable  232  can be extensions of the conductive wires in cable  230  that carry the digital audio or video signals. Thus, cable  230  with cables  232 ,  234 , and  236  can be made as an all electric cable, which can have continuous wires and be made in a single low cost process. For example, individual conductors for the wires can be on a spool, with the conductors going through a wrap to combine the conductors into one cable. 
       FIG. 3  is a flowchart illustrating an assembly process  300  for making a connector having an active optical component according to embodiments of the present invention. In various embodiments, the active optical component can be an optical transmitter, an optical receiver, or an optical transceiver that includes both an optical transmitter and an optical receiver in a single component.  FIGS. 4A-4L  show a connector at different stages of assembly process  300 . Certain parts of assembly process  300  may be occur in a different order than presented, while other parts do occur prior to other parts, as will be easily recognizable by one skilled in the art. 
     At block  305 , a light guide is inserted into a housing of the connector.  FIG. 4A  shows light guide  405  (e.g. a solid or hollow structure made of plastic or glass) being inserted into a front opening  412  of housing  410 . In one embodiment, front opening  412  has a height and a width of about 6 mm to a side. The height and width dimension of front opening  412  can persist through the length of housing  410 . The front opening may be square (as shown), circular, or other suitable shape. Housing  410  can also include additional openings on outer walls. In another embodiment, housing  410  is a single piece of insulating material (e.g. plastic). 
     In some embodiments, light guide  405  is coated, e.g., with metal. Such a construction can allow a separate subcomponent assembly. In one embodiment, the light guide (e.g. plastic) is inserted into a metal sleeve  407  (e.g. made of brass with nickel plating), or other cover. The light guide can then be cut at the ends of the sleeve and/or melted at the end. The ends of the light guide can then be polished. 
     At block  310 , a locking tab  420  (or other type of suitable locking member) is inserted into housing  410  through a slot opening  422  in an outer wall of housing  410 , as shown in  FIG. 4B . As shown, slot opening  422  is on a top outer wall of housing  410 , and locking tab includes posts  422 . In other embodiments, slot opening  422  may be on side outer walls or a bottom outer wall of housing  410 . Locking tab  420  can hold light guide  405  in place. In one embodiment, locking tab  420  can engage notches in a cover (e.g., metal sleeve  407 ) over light guide  405 . 
     At block  315 , an optical transmitter  430  or other active optical component is inserted into a top opening  432  in an outer wall of the housing  410 , as shown in  FIG. 4C . Top opening  432  can separate housing  410  into a front portion  417  and a back portion  419 . Optical transmitter  430  is shown having three terminals  434 . In one embodiment, the three terminals are inputs, where one is for power and two are for a differential electrical signal that is converted into the optical signal. In another embodiment, optical transmitter  430  is as wide as housing  410 . In one aspect, locking tab  420  fixes light guide  405  in place so that an air gap between optical transmitter  430  and light guide  405  is not too large (e.g. less than 2 mm). 
     At block  320 , a lock piece  440  is placed onto top opening  432 , as shown in  FIG. 4D . Lock piece may be made of plastic or other suitable material. In one aspect, lock piece  40  fixes optical transmitter  430  in place. A flat lower section  442  of lock piece  440  can fit into top opening  432  in back of optical transmitter  430  to keep it from moving back and forth so that the air gap between light guide  405  and optical transmitter  430  stays within a tolerance. In one embodiment, the lower section  442  can be wedged between an inner wall of housing  410  and the back of optical transmitter  430 . 
     In one embodiment, lock piece  440  includes locking elements  444  that fit into pockets on a top surface of housing  410 . In one aspect, locking elements  444  snap into place. Optical transmitter  430  can be free until the plastic lock is snapped in. Once locked into housing  410 , lock piece  440  keep optical transmitter  430  in place. Lock piece  440  can also help keep locking tab  420  in place. Lock piece  440  can also gives structural integrity to housing  410 , which otherwise might only have a thin connection between front portion  417  and back portion  419 . Thus, lock piece  440  can act as a second load path for longitudinal stress on housing  410 . 
     At block  325 , one or more pins  450  are inserted through housing  410 , as shown in  FIG. 4E . In one embodiment, pins are stress fit into housing  410  through top holes  452 . 
     At block  330 , a circuit board  460  is added to a bottom of housing  410 , as shown in  FIG. 4F . In one embodiment, circuit board  460  is a printed circuit board (PCB). As shown, circuit board  460  includes holes for posts  422  of locking piece  420 , terminals  434  of optical transmitter  430 , and pins  450 . In another embodiment, circuit board  460  can have a bypass cap and termination resistors to reduce ringing from the electrical signals. When the electrical signals are a square wave (e.g. 0 volts to 1 or 2 volts), the electrical signals can have overshoot, which can be reduced by circuitry on the circuit board before the signals reach optical transmitter  430 . 
     At block  335 , terminals  434  of optical transmitter  430  are electrically connected (e.g. soldered) to circuit board  460 , as shown in  FIG. 4G . In one embodiment, terminals  434  are soldered to edges of holes of circuit board  460 , where the edges include a conductive materials. Posts  422  of locking piece  420  and solder pins  450  can be bonded (e.g. also soldered or attached with an adhesive material) to circuit board  460 . In one embodiment, the soldering is performed by hand. 
     Having circuit board  460  connected in front (to posts  422 ) of terminals  434  and in back (to pins  450 ) of terminals  434  can add strength (e.g. by forming a rigid box) to circuit board  460 . Also, such connections can keep the electrically active connection to terminals  434  from breaking as forces will likely be absorbed by the connections to posts  422  and pins  450 . Thus, in case circuit board  460  is stressed, stressed solder joints that are not critical, i.e. not being used for an electrical connection, can bear the brunt of the stress. 
     At this point, the connector is a self-contained unit, which adds a benefit over putting the transmitter in a splitter, which is part of the cable assembly. Thus, this connector can be added to any device in this form. 
     At block  340 , cable wires  474  of cable  470  are electrically connected to circuit board  460 , as shown in  FIG. 4H . In the embodiment shown, three cable wires (1 for power and 2 data) are soldered to respective solder pads  472  of circuit board  460 . In one embodiment, the soldering is performed by hand. In an embodiment, a cable manufacturer may receive the connector completed at block  335 , and the cable manufacturer may perform block  340  and on. 
     At block  345 , a cable band  480  that runs through cable  470  is attached to housing  410 , as shown in  FIG. 4I . Cable band  480  may be made of Kevlar or other suitably strong material. In one embodiment, cable band  480  is tied around a bar  482  at the back end of housing  410 . Thus, when cable  470  is pulled, the connections of the wires  474  on solder pads  472  are not broken by wires  474  being pulled. Additionally, when cable  470  is pulled, the load is carried through housing  410  and lock piece  440 . Also, if a force pulls on the front of the connector, the load and can be carried in a similar manner. 
     At block  350 , an inner mold  485  is applied around a back end of circuit board  460 , as shown in  FIG. 4J . In one embodiment, inner mold  485  is polyethylene or other suitable material. In another embodiment, inner mold  485  is applied in a vertical inner mold machine using relatively low pressure compared to plastics molding for the housing. Inner mold  485  can provide rigidity to wires  474  at the end of cable  470 . 
     At block  355 , a strain relief over mold  490  is applied over part of inner mold  485  and cable  470 , as shown in  FIG. 4K . Over mold  490  can prevent damage to cable  470  inside or near inner mold  485 . For example, stresses from conical or side-to-side motion can be reduced to prevent damage. 
     At block  360 , an enclosure  495  is placed over part of housing  410 , as shown in  FIG. 4L . In one embodiment, an enclosure  495  is already over cable  470 , and it is just slid around over mold  490  and part of housing  410 . As housing  410  may have a same width and height throughout its length, enclosure  495  can be easily slid over housing  410 . In another embodiment, enclosure  495  can be glued to housing  410 . 
       FIG. 5  shows a cross-sectional side view of male optical connector  500  that includes an optical transmitter  530  according to embodiments of the present invention. Male optical connector  500  is shown mated with a female receptacle connector  599 , e.g. optical connector  192  of receiving device  190 , as shown in  FIG. 1 . In one embodiment, as part of mating, a housing  510  of male optical connector  500  can fit partially or completely inside of female receptacle connector  599 . 
     As drawn, the electrical signals enter from the right through cable  570  and generally travel to the left. For an active optical element that includes an optical receiver, the electrical signals would generally travel to the right, as drawn. The electrical signals can travel on wires  574 , which are soldered to circuit board  560 . Circuit board  560  has conductive traces that carry the electrical signals from wires  574  to optical transmitter  530 . The electrical signals may include power for powering optical transmitter  530  and data signals (e.g. a differential signal). Optical transmitter  530  converts the electrical signals into optical signals. The optical signals can be transmitted to a light guide  505 , which carries the optical signals to receptacle connector  599 . In various embodiments, light guide  505  can extend past a front edge of housing  510 , just to the front edge, or stop before the front edge (e.g. if the female connector has a light guide that fits into housing  510 ). 
     Locking tab  520  can be attached to a metal sleeve  507  that surrounds light guide  505  to keep light guide  505  aligned with and within a specified distance of optical transmitter  530 . Posts  522  of locking tab  520  can be bonded (e.g., soldered) to circuit board  560 . One or more pins  550  can be disposed vertically through housing  510  and can also be bonded to circuit board  560 . These additional connections from components that are structurally connected with housing  510  to circuit board  560  can help reduce movement of circuit board  560  that might damage the active solder connection of optical transmitter  530  to circuit board  560 . 
     A cable band  580  (e.g. made of Kevlar) runs through cable  570  and is attached (e.g. tied) to housing  510 , in order to provide stress relief to the solder connections of wires  574 . A lock piece  540  can carry at least part of the load from a force on cable band  580 , which may result from cable  570  being pulled. For example, lock piece  540  has locking elements  544  that fit into pockets on housing  510 . Thus, when a force occurs along the length of housing  510  lock piece  540  can convey the force along with a bottom part of housing  510 . 
     The opening in housing  510 , in which lock piece  540  is put, may be used for insertion of optical transmitter  530 . An over mold  590  can also provide stress relief to wires  574 . An enclosure  595  can surround part of over mold  590  and part of housing  510 . 
     Embodiments described herein provide connectors and cable adapters for accommodating electrical and optical signals. In some embodiments, a connector includes an optical transmitter for converting electrical signals to optical signals. For example, a first connector of a cable adapter can receive electrical signals, which may correspond to multiple data formats. The cable adapter can then transmit the electrical signals to multiple second connectors, of which at least one second connector can convert the electrical signals to optical signals. Such a cable adapter can provide a low cost and compact solution for providing communication from a sending device to multiple receiving devices, where one of the receiving devices receives optical signals. 
     The specific details of particular embodiments may be combined in any suitable manner or varied from those shown and described herein without departing from the spirit and scope of embodiments of the invention. 
     The above description of exemplary embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.

Metadata:
Filing Date: 20100416
Publication Date: 20131022
Grant Date: 20131022
Priority Date: 20100416
Inventors: SCHMIDT MATHIAS
RABU STAN
Assignee: APPLE INC
CPC Classifications: [{"code": "G02B6/4284", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B10/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/4439", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y10T29/49204", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B10/50", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/421", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B10/801", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/38", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B6/421", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B6/4201", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B6/4284", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/49204", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B6/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/4292", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01D5/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/4201", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/4292", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 44279058