An arrangement for improving adhesive attachment of micro-components in an assembly utilizes a plurality of parallel-disposed slots formed in the top surface of the substrate used to support the micro-components. The slots are used to control the flow and "shape" of an adhesive "dot" so as to quickly and accurately attach a micro- component to the surface of a substrate. The slots are formed (preferably, etched) in the surface of the substrate in a manner that lends itself to reproducible accuracy from one substrate to another. Other slots ("channels") may be formed in conjunction with the bonding slots so that extraneous adhesive material will flow into these channels and not spread into unwanted areas.
A silicon-based optical modulator is configured as a multi-segment device that utilizes a modified electrical data input signal format to address phase modulation nonlinearity and attenuation problems associated with free-carrier dispersion-based modulation. The modulator is formed to include M separate segments and a digital signal encoder is utilized to convert an N bit input data signal into a plurality of M drive signals for the M modulator segments, where M ≥ 2N/2. The lengths of the modulator segments may also be adjusted to address the nonlinearity and attenuation problems. Additional phase adjustments may be utilized at the output of the modulator (beyond the combining waveguide).
G02F 1/01 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour
3.
HDMI TMDS OPTICAL SIGNAL TRANSMISSION USING PAM TECHNIQUE
An HDMl interconnect arrangement is presented that performs a pulse-amplitude modulation (PAM) conversion of the TMDS audio/video signals in order to simultaneously transmit all three channels over a single optical fiber. The set of three audio/video TMDS channels is applied as an input to a PAM-8 optical modulator, which functions to encode the set of three channels onto an optically-modulated output signal. The modulated optical signal is thereafter coupled into an optical fiber within an active HDMI cable and transmitted to an HDMI receiver (sink). The TMDS CLK signal is not included in this conversion into the optical domain, but remains as a separate electrical signal to be transmitted along a copper signal path within the active HDMI cable.
A silicon-based optical modulator exhibiting improved modulation efficiency and control of ''chirp" (i.e., time-varying optical phase) is provided by separately biasing a selected, first region of the modulating device (e.g., the polysilicon region, defined as the common node). In particular, the common node is biased to shift the voltage swing of the silicon-based optical modulator into its accumulation region, which exhibits a larger change in phase as a function of applied voltage (larger OMA) and improved extinction ratio. The response in the accumulation region is also relatively linear, allowing for the chirp to be more easily controlled. The electrical modulation input signal (and its inverse) are applied as separate inputs to the second region (e.g., the SOI region) of each arm of the modulator.
G02F 1/01 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour
5.
OPTICAL INTERCONNECTION ARRANGEMENT FOR HIGH SPEED, HIGH DENSITY COMMUNICATION SYSTEMS
An optical interconnection arrangement for use in high data applications is presented that eliminates the need for extensive serialization/de-serialization (SERDES) functionality by utilizing pulse amplitude modulation (PAM) techniques to represent the data in the optical domain while utilizing a separate channel for transmitting an optical clock signal, eliminating the need for clock recovery circuitry on the receive end of the arrangement.
H04B 10/00 - Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
A multiple piecepart alignment and attachment configuration for mating a fiber array (or even a single fiber) with a silicon photonic subassembly utilizes ever-tightening alignment tolerances to align the fiber array with a similar array of waveguides (or other devices) formed within the photonic subassembly. A box-shaped fiber holder is formed to include a plurality of grooves within its bottom interior surface to initially support the fiber array. A separate piecepart in the form of a lid is mated to, and aligned with, the silicon photonic subassembly. The lid is formed to include registration features on its underside that fit into alignment detents formed in the top surface of the silicon photonic subassembly upon attachment. The lid also includes a number of grooves formed on its underside that will capture the top surface of the fibers as the fiber holder is slide into place over the lid. The grooves within the lid function to tighten the pitch of the fiber array and ultimately control the lateral and vertical alignment between the fiber array and the subassembly. The subassembly is also formed to include etched channels along the endface (the channels aligned with optical waveguides/devices in the substrate) to mate with the fiber holder, where the optical fibers are ultimately positioned within the channels so as to be in alignment with the optical waveguides/devices.
G02B 6/38 - Mechanical coupling means having fibre to fibre mating means
G02B 6/04 - Light guidesStructural details of arrangements comprising light guides and other optical elements, e.g. couplings formed by bundles of fibres
7.
TWO-DIMENSIONAL LENSING ARRANGEMENT FOR OPTICAL BEAM COLLIMATION AND BEAM ORIENTATION
An arrangement for collimating and turning an optica! beam utilizing a pair of two-dimensional lenses to separate the collimation into separate one-dimensional operations, while using one of the two-dimensional lenses to also perform the turning operation. A first two-dimensional Sensing surface is disposed at the endface of a launching waveguide. This first two-dimensional lensing surface provides collimation along one axis of the system (for example, the X axis). A second two-dimensional lensing surface is provided by introducing a defined curvature to a turning mirror in the system. The curvature of the turning mirror is designed to create colϋmation (or focusing, if desired) in the orthogonal beamfront (in this case, the Y axis beamfront), while also re-directing the propagating signal into the desired orientation.
An optical coupler is formed of a low index material and exhibits a mode field diameter suitable to provide efficient coupling between a free space optical signal (of large mode field diameter) and a single mode high index waveguide formed on an optical substrate. One embodiment comprises an antiresonant reflecting optical waveguide (ARROW) structure in conjunction with an embedded (high index) nanotaper coupling waveguide. Another embodiment utilizes a low index waveguide structure disposed in an overlapped arrangement with a high index nanotaper coupling waveguide. The low index waveguide itself includes a tapered region that overlies the nanotaper coupling waveguide to facilitate the transfer of the optical energy from the low index waveguide into an associated single mode high index waveguide.
G02B 6/12 - Light guidesStructural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
A plasma-based etching process is used to specifically shape the endface of an optical substrate supporting an optical waveguide into a contoured facet which will improve coupling efficiency between the waveguide and a free space optical signal. The ability to use standard photolithographic techniques to pattern and etch the optical endface facet allows for virtually any desired facet geometry to be formed - and replicated across the surface of a wafer for the entire group of assemblies being fabricated. A lens may be etched into the endface using a properly-defined photolithographic mask, with the focal point of the lens selected with respect to the parameters of the optical waveguide and the propagating free space signal. Alternatively, an angled facet may be formed along the endface, with the angle sufficient to re-direct reflected/scattered signals away from the optical axis.
A silicon-insulator-silicon capacitive (SISCAP) optical modulator is configured to provide analog operation for applications which previously required the use of relatively large, power-consuming and expensive lithium niobate devices. An MZI- based SISCAP modulator (preferably a balanced arrangement with a SISCAP device on each arm) is responsive to an incoming RF electrical signal and is biased in a region where the capacitance of the device is essentially constant and the transform function of the MZI is linear.
G02B 6/10 - Light guidesStructural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
11.
SOI STRUCTURE INCLUDING NANOTAPER WITH IMPROVED ALIGNMENT CAPABILITIES TO EXTERNAL LIGHT GUIDE
An arrangement for providing alignment between an optical nanotaper coupler and a free space optical signal includes the formation of a 'ridge' structure around the location of the nanotaper coupler to reduce stray light-related errors in the alignment process. The ridge is preferably formed by etching vertical sidewalls through the inter-level dielectric (ILD) and buried oxide (BOX) layers of the SOI structure. When an optical source (such as an illuminated fiber, laser, etc.) is scanned across this etched arrangement, the signal received by an associated photodetector registers an increase at the boundary between the etched region and the vertical sidewall of the ridge, thus defining the bounds within which the nanotaper coupler is located. Since the dimensions of the ridge are known and controlled by the etching process, the location of the nanotaper coupler tip along the endface of the ridge can be determined from this scan.
One or more nanotaper coupling waveguides formed within an optical substrate allows for straightforward, reproducible offset launch conditions to be achieved between an incoming signal and the core region of a multimode fiber (which may be disposed along an alignment fixture formed in the optical substrate), fiber array or other multimode waveguiding structure. Offset launching of a single mode signal into a multimode fiber couples the signal into favorable spatial modes which reduce the presence of differential mode dispersion along the fiber. This approach to providing single mode signal coupling into legacy multimode fiber is considered to be an improvement over the prior art which required the use of an interface element between a single mode fiber and multimode fiber, limiting the number of propagating signals and applications for the legacy multimode fiber. An optical switch may be used to select the specific nanotaper(s) for coupling into the multimode fiber.
A unitary optical receiver assembly is formed to include a V-groove passively aligned with a first aspheric lens (the lens formed along a surface perpendicular to the V-groove). An optical fiber is disposed along the V-groove and is used to bring the received optical signal into the unitary assembly. Upon passing through the first aspheric lens, the received optical signal will intercept a 45° turning mirror wall that directs the signal downward, through a second aspheric lens (also molded in the unitary assembly), and then into a photosensitive device. Advantageously, the photosensitive device is disposed in passive alignment with the second aspheric lens, allowing for a received signal to be coupled from an incoming optical fiber to a photosensitive device without needing any type of active alignment therebetween.
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