Free-space optical interconnect with asymmetric light pipes
AssigneeHewlett-Packard Development Company, L.P.
InventorsMichael Tan, Sagi Mathai, Paul Rosenberg
Life of this patent
Estimating the term…
Abstract
An optical interconnect system includes components such as circuit boards, server blades, or a backplane with respective light pipes for an optical signal. The light pipe in a component transmitting the optical signal receives a collimated beam and directs the collimated beam for transmission. The light pipe in a receiving component is nominally aligned with the light pipe pf the transmitting component and separated from the first light pipe by free space. The light pipe on the receiving side is larger than the light pipe on the transmitting side and can therefore accommodate an expected alignment error.
Claims20
An optical interconnect system comprising:
- a first component including a first block through which a first light pipe extends, the first light pipe being positioned to receive a first optical signal and to direct the first optical signal for transmission from the first component, wherein the first light pipe comprises a hollow tube having reflective walls and a cross-section of a first size;
- and
- a second component including a second light pipe nominally aligned with the first light pipe and separated from the first light pipe by a free-space gap, wherein the second light pipe comprises a hollow tube having reflective walls and a cross-section of a second size that is larger than the first size, and wherein:
- the first block further includes a third light pipe that extends through the first block as a hollow tube having reflective walls and a cross-section of the second size;
- the second component further includes a fourth light pipe that comprises a hollow tube having reflective walls and a cross-section of the first size;
- and
- the third light pipe and the fourth light pipe are nominally aligned for transmission of a second optical signal from the second component, through the fourth light pipe, across the free-space gap, and into the third light pipe.
A method for transmitting information comprising:
- directing a plurality of first optical signals from a first component respectively into a plurality of first light pipes extending through a first block, wherein each of the first light pipes comprises a hollow tube having reflective walls and having a cross-section of a first size;
- aligning a second block containing a plurality of second light pipes with the first block, wherein the aligning has an expected alignment error, and each of the second light pipes comprises a hollow tube having reflective walls and has a cross-section of a second size that is larger than the first size by a margin that accommodates the expected alignment error;
- and
- receiving the first optical signals from across a free-space gap between the first and second blocks and through the second light pipes into a second component.
An optical interconnect system comprising:
- a first block containing a first light pipe and a second light pipe, wherein the first light pipe comprises a hollow tube having reflective walls and a first cross-section, and the second light pipe comprises a hollow tube having reflective walls and a second cross-section that is larger than the first cross-section;
- and
- a second block containing a third light pipe and a fourth light pipe, wherein the third light pipe comprises a hollow tube having reflective walls and the second cross-section, the fourth light pipe comprises a hollow tube having reflective walls and the first cross-section, and wherein:
- the first light pipe and the third light pipe are aligned for optical transmissions through the first light pipe, across a free space gap, and into the third light pipe;
- and
- the second light pipe and the fourth light pipe are aligned for optical transmissions through the fourth light pipe, across the free space gap, and into the second light pipe.
Dependencies are inferred from the claim text.