Optical communication system adapted for receiving an optical signal at a plurality of different positions

An optical communication system (200) for transmitting light between a first housing (102) and a second housing (104) of a device (100) is provided. The first housing and the second housing are adapted to move relative to one another between a plurality of usage positions. The optical communication system includes a first optical communication element (202), a second optical communication element (204), and an optical waveguide (206). The first optical communication element is capable of emitting light and can be coupled to one of the first and second housing. The second optical communication element is capable of receiving the light and can be coupled to the housing to which the first optical communication element is not coupled. The optical waveguide is capable of conveying the light emitted by the first to the second optical communication element. The second optical communication element can substantially encompass a locus of the output light.

FIELD OF THE INVENTION

The present invention relates generally to a communication system between multiple housings of a device, the multiple housings being adapted to move relative to one another, and more specifically, to an optical communication system having an optical communication element adapted to receive an optical signal at a plurality of different positions.

BACKGROUND OF THE INVENTION

In recent times, the use of active elements in a communication device the need to communicate with one another has substantially increased. Examples of the active elements include, but are not limited to, a camera, a display, and a fingerprint sensor. The active elements need to be physically linked and/or communicatively coupled to other elements in the communication device. Examples of the communication device include, but are not limited to, a mobile phone, a radio telephone, a music playback device (i.e. an MP3 player), a pager, a laptop computer, a desktop computer, and a Personal Digital Assistant (PDA). In at least one commonly used configuration, the communication device can include a first housing and a second housing, which can be adapted to move relative to one another. A sufficiently large number of the active elements, which need to communicate with one another are coupled to alternative ones of the first housing and/or the second housing of the communication device. This results in a substantial amount of data, such as video content and audio content, that needs to be transmitted between the first housing and the second housing.

In one of the known methods for transmitting data between the first housing and the second housing, the data is routed via a multi-layer electric flex circuit. The multi-layer electric flex circuit generally includes multiple layers of high-density conductive traces interleaved with an insulating material. The multi-layer electric flex circuit passes through a restricted space between the first and the second housing. However, the multi-layer electric flex circuit can be mechanically unreliable and can cause greater radio-frequency interference when a greater number of signals and/or signals having higher data rates are routed via the flex circuit through the restricted space. In another known method, the data is serialized before transmission. This can highly simplify the multi-layer electric flex circuit and improve the mechanical reliability and cost associated with the multi-layer electric flex circuit. However, this does not always result in the reduction of radio-frequency interference to a level at or below a desired level, as the data rates often need to increase to accommodate the fewer number of communication paths.

In light of the above mentioned discussion, there is a need for a communication system for data transmission between the multiple housings of a communication device which can limit the radio-frequency interference. The communication system should be capable of transmitting an increased amount of data without increasing the radio-frequency interference. Further, the communication system should enable relatively high-speed data transmission between the multiple housings.

SUMMARY OF THE INVENTION

The present invention provides an optical communication system for transmitting light between a first housing and a second housing of a device. In the present invention, a signal in the form of light (i.e. an electromagnetic radiation) is used in the device for data transmission between a first optical communication element and a second optical communication element of the device. In at least one embodiment of the present invention, the optical communication system for transmitting the light between the first housing and the second housing of the device is provided. The first housing and the second housing can be adapted to move relative to one another, a distance corresponding to a travel distance between a plurality of usage positions. The optical communication system includes a first optical communication element, a second optical communication element, and an optical waveguide. The first optical communication element can emit the light and can be coupled to either the first housing or the second housing. The second optical communication element can receive the light and can be coupled to other one of the first housing and the second housing to which the first optical communication element is not coupled. The optical waveguide can convey the light emitted by the first optical communication element to the second optical communication element. The output light from the optical waveguide is adapted to be received by the second optical communication element at each of a plurality of different positions of an end of the optical waveguide as the first and second housings move between the plurality of usage positions.

In a further embodiment of the present invention, a device is provided. The device can include a two-part housing and one or more optical communication systems. The two-part housing can include a first housing and a second housing. The first housing and the second housing can be adapted to move relative to one another between a plurality of usage positions. The one or more optical communication systems can transmit light between the first housing and the second housing. Further, each optical communication system of the one or more optical communication systems can include a first optical communication element, a second optical communication element, and an optical waveguide. The first optical communication element can emit the light and can be coupled to either the first housing or the second housing. The second optical communication element can receive the light and can be coupled to other one of the first housing and the second housing to which the first optical communication element is not coupled. The optical waveguide can convey the light emitted by the first optical communication element to the second optical communication element. The output light from the optical waveguide is adapted to be received by the second optical communication element at each of a plurality of different positions of an end of the optical waveguide as the first and second housings move between the plurality of usage positions.

These and other features, as well as the advantages of this invention, are evident from the following description of one or more embodiments of this invention, with reference to the accompanying figures.

DETAILED DESCRIPTION

Before describing in detail the particular system for communication, in accordance with the present invention, it should be observed that the present invention resides primarily as apparatus components related to an optical communication system. Accordingly, the apparatus components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent for an understanding of the present invention, so as not to obscure the disclosure with details that will be readily apparent to those with ordinary skill in the art, having the benefit of the description herein.

In this document, the terms ‘comprises,’ ‘comprising,’ ‘includes,’ or any other variation thereof are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements, but may include other elements that are not expressly listed or inherent in such an article or apparatus. An element proceeded by ‘comprises . . . a’ does not, without more constraints, preclude the existence of additional identical elements in the article or apparatus that comprises the element. The term ‘another,’ as used in this document, is defined as at least a second or more. The terms ‘includes’ and/or ‘having’, as used herein, are defined as comprising.

FIG. 1illustrates a device100having a first housing102and a second housing104, where various embodiments of the present invention can be applicable. The first housing102and the second housing104are adapted to move relative to one another. Examples of the device100can include, but are not limited to, a wireless communication device, a radio telephone, a pager, a laptop computer, a music playback device (i.e. an MP3 Player), and a personal digital assistant (PDA). The first housing102and the second housing104can move relative to one another a distance corresponding to a travel distance of either the first housing102or the second housing104, between a plurality of different usage positions. The travel distance is the relative distance traversed either by the first housing102or the second housing104with respect to the other while moving relative to each other. In at least one embodiment, the plurality of the different usage positions can include, but are not limited to, a closed position and an open position of either the first housing102or the second housing104. An arrow106inFIG. 1illustrates the potential movement of the first housing102and the second housing104relative to one another, which can result in the closed position, the open position, and any number of positions in between. In the particular embodiment illustrated inFIG. 1, the first housing102and the second housing104can travel along a pair of substantially parallel paths relative to one another. This is sometimes referred to as the slider configuration of the device100.

In a further embodiment of the present invention, either the first housing102or the second housing104can include one or more active elements that need to be physically and/or communicatively coupled to one or more corresponding elements present on either the same or the other one of the first housing102and the second housing104. Examples of the active elements can include, but are not limited to, a camera, a display, and a fingerprint sensor. For example, a camera present on the first housing102may need to be communicatively coupled to a microprocessor present on the second housing104.

FIG. 2illustrates an optical communication system200for use in a device having the first housing102and the second housing104, in accordance with at least one embodiment of the present invention. Examples of the device can include the device100illustrated inFIG. 1. Though the optical communication system200is explained in conjunction withFIG. 1, it would be apparent to a person ordinarily skilled in the art that the optical communication system200can be implemented in communication devices having other types of configurations.

The optical communication system200includes a first optical communication element202, a second optical communication element204, and an optical waveguide206. The first optical communication element202can emit light. Examples of the first optical communication element202can include, but are not limited to, a laser source, a light emitting diode, a vertical-cavity surface emitting laser, and an edge-emitting diode. Further, the first optical communication element202can be coupled to either the first housing102or the second housing104. For the purpose of this description, the first optical communication element202is shown to be coupled to the first housing102. In at least one embodiment, the first optical communication element202can produce the light having one or more controlled characteristics. Examples of the one or more controlled characteristics of the light can include, but are not limited to, amplitude, frequency, and phase. The one or more characteristics can be varied in accordance with a characteristic of an incoming signal to encode and/or superimpose a stream of data on the light produced. The stream of data can be received from one or more active elements. For example, the light emitted by the first optical communication element202can be varied in accordance with a current applied to it.

In at least one embodiment, the light emitted by the first optical communication element202can be received by the second optical communication element204. The second optical communication element204can be coupled to the other one of the first housing102and the second housing104to which the first optical communication element202is not coupled. For the purpose of this description, the second optical communication element204is shown to be coupled to the second housing104. The second optical communication element204can include either or both of one or more point optical communication elements and one or more strip optical communication elements. An example of the point optical communication element can include a photo-diode. Further, an example of the strip optical communication element can include a photo-detector strip. In at least one embodiment, the optical communication system200can include an electrical summation circuit. The electrical summation circuit can sum up the detected photo-current by either or both of the one or more point optical communication elements and the one or more strip optical communication elements.

In at least one embodiment, the light is conveyed to the second optical communication element204by the optical waveguide206. The optical waveguide206can convey the light emitted by the first optical communication element202to the second optical communication element204. Examples of the optical waveguide206can include, but are not limited to, a rigid waveguide, a flexible waveguide, a light pipe, an optical fiber, and an acrylic fiber. In at least one embodiment of the present invention, a first end208of the optical waveguide206can be coupled to either the first housing102or the second housing104to which the first optical communication element202is coupled. For example, the first end208can be coupled to the first housing102by a rotary joint. Examples of the rotary joint can include, but are not limited to, a pivot joint, a single channel rotary joint, and a multi channel rotary joint. The rotary joint can allow the optical waveguide206to rotate about an axis210that can pass through the first end208. The axis210can be perpendicular to a plane along which the first housing102can move with respect to the second housing104. The first end208can receive the light emitted by the first optical communication element202. The optical waveguide206can output the light through a second end212of the optical waveguide206to the second optical communication element204.

In at least one embodiment, the second end212can be coupled to either the first housing102or the second housing104to which the second optical communication element204is coupled, using a grooved-pin joint214. For the purpose of this description, the second end212is shown to be coupled to the second housing104. The grooved-pin joint214can enable transformation of a rotatory motion of the optical waveguide206about the axis210to a translation motion of the second end212with respect to the second housing104.

When the first housing102moves relative to the second housing104from an open position to a closed position or vice-versa, coupling of the optical waveguide206at both the ends causes the second end212to move in a restricted path with respect to the second housing104. This restricted path can be referred to as a locus of the output light, and corresponds to each of a plurality of different positions of the end of the optical waveguide corresponding to the second optical communication element as the first and second housing move between the plurality of use positions. The locus of the output light is explained in detail in the description ofFIG. 3. The second optical communication element204can substantially encompass the locus of the output light emitted by the optical waveguide206between the plurality of usage positions. Further, in at least some instances, the second optical communication element204can receive the light at some or all of the intermediate positions in between.

In at least one embodiment, a pin of the grooved-pin joint214can act as the second end212which can output the light conveyed by the optical waveguide206. In this embodiment, the locus of the output light can coincide with a groove of the grooved-pin joint214.

In the embodiment, where the optical waveguide206is a flexible waveguide, the second end212can be coupled to the second housing104using a rotary joint. The rotary joint can allow the optical waveguide206to rotate about an axis that can pass through the second end212. The axis is perpendicular to the plane along which the first housing102moves with respect to the second housing104. Further, the optical communication system200can include an optical light collector216. The optical light collector216can direct the output light from the second end212of the optical waveguide206to the second optical communication element204. Examples of the optical light collector216can include, but are not limited to, a lens, a compound parabolic collector, a cone, and a V-shaped guide. The optical light collector216can substantially encompass the locus of the output light.

It is apparent that a person ordinarily skilled in the art will appreciate that the optical communication system200can include additional components that are not shown here since they are not germane to the operation of the optical communication system200, in accordance with the inventive arrangements.

FIG. 3illustrates a locus of output light with respect to a housing of an optical communication system, in accordance with at least one embodiment of the present invention. For the purpose of this description, the locus of the output light with respect to the second housing104has been illustrated. The locus of the output light with respect to the second housing104is illustrated by output positions302,304,306,308and310. It is apparent that a person ordinarily skilled in the art will appreciate that the locus of the output light can include one or more intermediate output positions between the illustrated output positions output positions302,304,306,308and310. As noted previously, the output positions302,304,306,308and310, each represent the respective positions of the second end212of the optical waveguide206with respect to the second housing when the first housing102moves with respect to the second housing104. The output position302can represent a position of the output light for an open position of the first housing102with respect to the second housing104. The output position304can represent the position of the output light for a closed position. The output position306can represent the position of the output light for a position partially halfway between the open and the closed positions. The output positions308and310can represent the position of the output light for further intermediate positions.

In at least one embodiment, the second optical communication element204can substantially encompass the locus of the output light as described above. This can enable the second optical communication element204to receive the output light at all of the usage positions.

FIG. 4illustrates a view of the optical communication system200for use in a device having a two-part housing, in accordance with at least one embodiment of the present invention. Examples of the device can include the device100, illustrated inFIG. 1. The device can include a two-part housing and one or more optical communication systems. The two-part housing can include the first housing102and the second housing104. The first housing102and the second housing104can be adapted to move relative to one another between a plurality of usage positions. For the purpose of this description, the device is shown to include one optical communication system200.

Similar to the optical communication system described in connection withFIG. 2, the optical communication system200can transmit light between the first housing102and the second housing104. The optical communication system200can include the first optical communication element202, the second optical communication element204, and the optical waveguide206. The first optical communication element202can emit the light. Further, the first optical communication element202can be coupled to either the first housing102or the second housing104. For the purpose of this description, the first optical communication element202is shown to be coupled to the first housing102.

The second optical communication element204can receive the light. Further, the second optical communication element204can be coupled to other one of the first housing102and the second housing104to which the first optical communication element202is not coupled. The light received by the second optical communication element204is conveyed to it by the optical waveguide206. The optical waveguide206can convey the light emitted by the first optical communication element202to the second optical communication element204. The second optical communication element204can substantially encompass a locus of the output light emitted by the optical waveguide206between the plurality of usage positions. The first end208of the optical waveguide206is illustrated to be coupled to the first housing102to which the first optical communication element202is coupled using a rotary joint. Further, the second end212is illustrated to be coupled to the second housing104to which the second optical communication element204is coupled. The second end212can be coupled using a grooved-pin joint214.

The optical light collector216of the optical communication system200can direct the output light from the second end212to the second optical communication element204. The optical light collector216can substantially encompass the locus of the output light.

In at least one embodiment, the device can include a first optical communication system and a second optical communication system to enable two-way transmission of light between the first housing102and the second housing104. The first optical communication element of the first optical communication system can be coupled to the first housing102and the second optical communication element of the first optical communication system can be coupled to the second housing104. The first optical communication element of the second optical communication system can be coupled to the second housing104and the second optical communication element of the second optical communication system can be coupled to the first housing102. Further, the optical waveguide of the first optical communication system can convey the light emitted by the first optical communication element to the second optical communication element of the first optical communication system. Similarly, the optical waveguide of the second optical communication system can convey the light emitted by the first optical communication element to the second optical communication element of the second optical communication system.

In at least one embodiment of the present invention, the first optical communication system and the second optical communication system can include a single optical waveguide. The optical waveguide can be capable of conveying the light emitted by the first optical communication element to the second optical communication element of each of the first optical communication system and the second optical communication system.

Those ordinarily skilled in the art will appreciate that the device can include all or even a fewer number of components than the components shown inFIG. 4. Further, those ordinarily skilled in the art will understand that the device can include additional components that are not shown here since they are not germane to the operation of the device, in accordance with the inventive arrangements.

Various embodiments of the present invention, as described above, provide an optical communication system for transmitting light between a first housing and a second housing of a device. The optical communication system in the present invention does not involve the use of a multi-layer electric flex circuit, thereby increasing reliability of the device, avoiding a source of radio-frequency interference, and simplifying assembly of the device. Further, the invention provides a compact system that enables optical data transmission between the first housing and the second housing of the device.