Apple's Patent Background on Optical Cables & Adapters

Optical cables could 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 could 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 could have certain advantages over electrical cables, but also could have disadvantages. For example, the optical cables could malfunction if they are bent. Also, an optical cable typically only receives a single pulse of light at a time. Thus, the cables could 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 could 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 could handle multiple protocols as well as provide signals to an optical interface. It is also desirable to have low cost cables that could provide a connection from an electrical output to an optical input while maintaining a small form factor.

Apple's Solution

Apple's present invention could provide cable adapters and connectors that receive electrical signals and output optical signals. For example, a cable adapter could 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 could 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 could 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.

Optical Cable Adapter Patent Figures

Apple's patent 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. The cable adapter receives electrical signals from sending device 180, converts the electrical signals into optical signals, and provides the optical signals to receiving device 190. The sending device could 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 could have any suitable form factor and number of contacts.

Optical connector 120 provides optical signals through light guide 122 to optical connector 192 of the receiving device. The light guide could be any suitable device that could 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. 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.

Apple's patent FIG. 2 shows a cable adapter 200 that could receive multiple electrical signals and outputs corresponding electrical and optical signals according to embodiments of the present invention. The cable adapter 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.

As an example, the electrical connector could 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 could be used for USB, 19 contacts could be used for HDMI, and three wires for S/PDIF [Toslink] (2 for differential signal and one for power for transmitter).

Apple's patent FIG. 5 shows a cross-sectional side view of male optical connector that includes an optical transmitter according to embodiments of the present invention; Patent FIGS. 4I to 4L depict an optical connector at different stages of assembly.

Apple's patent application was originally filed in Q2 2010 by inventors Mathias Schmidt and Stan Rabu. Wiki on Fiber Optical Cables

Notice: Patently Apple presents a detailed summary of patent applications with associated graphics for journalistic news purposes as each such patent application is revealed by the U.S. Patent & Trade Office. Readers are cautioned that the full text of any patent application should be read in its entirety for full and accurate details. Revelations found in patent applications shouldn't be interpreted as rumor or fast-tracked according to rumor timetables. Apple's patent applications have provided the Mac community with a clear heads-up on some of Apple's greatest product trends including the iPod, iPhone, iPad, iOS cameras, LED displays, iCloud services for iTunes and more. About Comments: Patently Apple reserves the right to post, dismiss or edit comments.

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