Author: claimsbot

1. An optical device, comprising:
a substrate;
a first cladding disposed on the substrate;
a first optical waveguide extended in a first direction on the first cladding, and having a first refractive index;
a side grating formed in at least one side of the first optical waveguide;
a second optical waveguide filling a space of the side grating, extended in a second direction across the first direction on the first cladding, and having a second refractive index; and
a second cladding disposed on the second optical waveguide, and having a third refractive index,
wherein the first refractive index is greater than the second refractive index, and the second refractive index is greater than the third refractive index.
2. The optical device of claim 1, wherein the second optical waveguide is extended onto the first optical waveguide, and the second cladding is disposed on the extended second optical waveguide.
3. The optical device of claim 1, wherein the second cladding is disposed to contact the first optical waveguide.
4. The optical device of claim 1, wherein the second optical waveguide is a silicon nitride layer or a silicon oxide nitride layer.
5. The optical device of claim 1, wherein the first cladding andor the second cladding are a silicon oxide layer.
6. The optical device of claim 1, wherein the second optical waveguide comprises:
a first taper region;
a straight line region; and
a second taper region,
wherein a size of the first taper region is greater than a size of the straight line region, and the size of the straight line region is greater than a size of the second taper region.
7. The optical device of claim 1, further comprising a third optical waveguide spaced apart from the first optical waveguide,
wherein the third optical waveguide contacts the second optical waveguide, and the second cladding is disposed on a portion of the third optical waveguide or over the third optical waveguide.
8. The optical device of claim 1, wherein the side grating is symmetrically disposed in both side surfaces of the first optical waveguide.
9. The optical device of claim 1, wherein the side grating comprises:
a first side grating disposed in a one side of the first optical waveguide; and
a second side grating disposed in other side of the first optical waveguide,
wherein the first and second side gratings are offset by each other within a range of period.
10. The optical device of claim 1, wherein the side grating is disposed in only a one side of the first optical waveguide.
11. The optical device of claim 1, wherein the side grating is slopingly disposed in a one side of the first optical waveguide.
12. The optical device of claim 1, further comprising a fourth optical waveguide disposed on a vertical grating formed in the second optical waveguide,
wherein the fourth optical waveguide is an optical fiber.
13. The optical device of claim 1, wherein the first and second optical waveguides are disposed on the same plane.
14. An optical device, comprising:
a substrate;
a first cladding disposed on the substrate;
a first optical waveguide extended in a first direction on the first cladding, and having a first refractive index;
a first side grating formed in at least one side of the first optical waveguide;
a second side grating formed in at least one side of the first optical waveguide to be spaced apart from the first side grating;
a second optical waveguide filling a space of the first side grating, extended in a second direction across the first direction on the first cladding, and having a second refractive index;
a third optical waveguide filling a space of the second side grating, extended in the second direction across the first direction on the first cladding, and having a third refractive index; and
a second cladding disposed on the second and third optical waveguides, and having a fourth refractive index,
wherein the first refractive index is greater than the second and third refractive indexes, and the second and third refractive indexes are greater than the fourth refractive index.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

1. A method for determining a combined motion estimate between digital images captured at different capture times, comprising:
using an electronic image capture device to capture at least two digital images of a scene at different capture times;
designating one of the digital images as a reference digital image, and the rest of the digital images to be non-reference digital images;
designating a plurality of image regions within the digital images, wherein each image region includes at least a subset of image pixels in the digital images;
determining a motion estimate for each image region by:
shifting the image regions within the non-reference digital images according to each of a plurality of spatial offsets relative to the image region within the reference digital image to determine a plurality of shifted image regions, wherein the spatial offsets include horizontal and vertical offset values, each of which correspond to an integer number of image pixels;
using a data processor to compute merit function values for each of the spatial offsets, wherein the merit function values are an indication of an amount of difference between the image region in the reference digital image and the shifted image regions in the non-reference digital images;
using a data processor to fit a fitting function having a predefined functional form to at least a subset of the computed merit function values, wherein the fitting function provides an estimated merit function value as a function of spatial offset; and
determining the motion estimate responsive to the fitting function;

determining the combined motion estimate by combining the motion estimates for the plurality of image regions, wherein the combined motion estimate is determined by forming a weighted combination of the motion estimates for the plurality of image regions, each motion estimate being weighted with a weighting coefficient, and wherein the weighting coefficient for each image region is determined responsive to the shape of the corresponding fitting function; and
storing an indication of the combined motion estimate in a processor-accessible memory.
2. The method according to claim 1 wherein the motion estimate for each image regions is a non-integer spatial offset corresponding substantially to a local minimum or local maximum of the corresponding fitting function.
3. The method according to claim 1 wherein the weighting coefficients for image regions where the corresponding fitting functions have steeper local minima are larger than the weighting coefficients for image regions where the corresponding fitting functions have shallower local minima.
4. The method according to claim 1 wherein the weighting coefficients for image regions where the corresponding fitting functions have larger second derivatives are larger than the weighting coefficients for image regions where the corresponding fitting functions have smaller second derivatives.
5. The method according to claim 1 wherein the fitting function has a parabolic functional form.
6. The method according to claim 1 wherein the digital images correspond to preview images captured using a digital still camera.
7. The method according to claim 1 wherein the digital images correspond to image frames of a digital video sequence.
8. The method according to claim 1 wherein the image region corresponds to a focus region identified by an auto-focus algorithm.
9. The method according to claim 1 wherein the image region corresponds to a detected face region within the captured digital images.
10. The method according to claim 1 wherein the image region corresponds to an image region having a high scene brightness level.
11. The method according to claim 1 wherein the image region corresponds to an image region having a high level of scene detail.
12. The method according to claim 1 wherein the image region corresponds to an image region where there is a large difference between the captured digital images.
13. The method according to claim 1 wherein the plurality of spatial offsets correspond to an array of horizontal and vertical offset values.
14. The method according to claim 1 wherein the plurality of spatial offsets are defined according to an iterative search strategy.
15. The method according to claim 1 wherein at least three digital images are captured, and wherein the spatial offsets used to shift the image regions within each of the non-reference digital images are scaled proportionally to a capture time difference between the reference digital image and the corresponding non-reference digital image.
16. The method according to claim 1 wherein merit function values are determined responsive to a mean absolute difference between pixel values for the image region in the reference digital image and corresponding pixel values for the shifted image regions in the non-reference digital images.
17. The method according to claim 1 wherein the motion estimate is an indication of the motion of an object within the scene.
18. The method according to claim 1 wherein combined motion estimates are determined for a plurality of different reference digital images captured at different times, and wherein the combined motion estimates for the different reference digital images are combined to determine a time-averaged motion estimate.
19. The method according to claim 18 wherein the time-averaged motion estimate is determined by forming a weighted combination of the combined motion estimates for the different reference digital images, each combined motion estimate being weighted with a weighting coefficient.
20. The method according to claim 19 wherein the weighting coefficients for more recent combined motion estimates are larger than the weighting coefficients for earlier combined motion estimates.
21. The method according to claim 20 wherein the number of combined motion estimates or the weighting coefficients for the combined motion estimates are determined responsive to a light level of the scene.
22. The method according to claim 1 wherein the combined motion estimate is adjusted as a function of a scene brightness value to compensate for the effects of image noise in the captured digital images.
23. The method according to claim 22 wherein the combined motion estimates are reduced for scene brightness values below a predefined threshold.
24. The method according to claim 1 further including:
determining one or more image capture settings responsive to the combined motion estimate; and
using the electronic image capture device to capture an archival image according to the determined image capture settings.
25. A method for determining a combined motion estimate between digital images captured at different capture times, comprising:
using an electronic image capture device to capture at least two digital images of a scene at different capture times;
designating one of the digital images as a reference digital image, and the rest of the digital images to be non-reference digital images;
designating a plurality of image regions within the digital images, wherein each image region includes at least a subset of image pixels in the digital images;
determining a motion estimate for each image region by:
shifting the image regions within the non-reference digital images according to each of a plurality of spatial offsets relative to the image region within the reference digital image to determine a plurality of shifted image regions, wherein the spatial offsets include horizontal and vertical offset values, each of which correspond to an integer number of image pixels;
using a data processor to compute merit function values for each of the spatial offsets, wherein the merit function values are an indication of an amount of difference between the image region in the reference digital image and the shifted image regions in the non-reference digital images;
using a data processor to determine a motion estimate responsive to the computed merit function values; and
using a data processor to determine a weighting coefficient associated with the motion estimate responsive to one or more statistics determined from the computed merit function values;

determining the combined motion estimate by combining the motion estimates for the plurality of image regions, wherein the combined motion estimate is determined by forming a weighted combination of the motion estimates for the plurality of image regions, each motion estimate being weighted using the associated weighting coefficient; and
storing an indication of the combined motion estimate in a processor-accessible memory.
26. The method according to claim 25 wherein the one or more statistics determined from the computed merit function values include a minimum merit function value, a mean of the merit function values, a range of the merit function values, a standard deviation of the merit function values, a first derivative of the merit function values with respect to spatial offset or a second derivative of the merit function values with respect to spatial offset, or a combination thereof.

1. A computer system configured to validate visual CAPTCHAs, the computer system comprising:
one or more hardware processors programmed, via executable code instructions, to implement:
a CAPTCHA generator module configured to generate a visual CAPTCHA comprising a moire pattern including a plurality of visual patterns in a first overlapping configuration, wherein at least one of the visual patterns is configured to be manipulated by a human user to update the moire pattern by combining the plurality of visual patterns in a second overlapping configuration that is different from the first overlapping configuration, and wherein at least one of the first overlapping configuration or the second overlapping configuration produce a secondary image including a first object that is not visible in separate visual patterns of the plurality of visual patterns, and wherein the moire pattern is configured to be perceived as including the first object by the human user viewing the moire pattern; and
a human validator module configured to:
receive user input data associated with the visual CAPTCHA,
compare the user input data to a description of the first object; and
determine whether the user input data was provided by a human based on said comparison.
2. The computer system of claim 1, wherein the plurality of visual patterns is automatically generated.
3. The computer system of claim 1, wherein the plurality of visual patterns is configured to be manipulated by the human user to a non-overlapping configuration.
4. The computer system of claim 1, wherein the plurality of visual patterns comprises a first set of concentric circle patterns and a second set of concentric circle patterns.
5. The computer system of claim 1, wherein the visual CAPTCHA is configured for display as part of a website.
6. The computer system of claim 1, wherein the visual CAPTCHA is configured to persistently display throughout a session.
7. The computer system of claim 6, wherein the persistent display of the visual CAPTCHA comprises visual alerts when user interaction is required.
8. The computer system of claim 1, wherein the visual CAPTCHA further comprises a first set of visual patterns and a second set of visual patterns, wherein a first answer to the first set of visual patterns is known and a second answer to the second set of visual patterns is unknown; and
wherein the user input data comprises a first input data corresponding to the first set of visual patterns and a second input data corresponding to the second set of visual patterns, and the human validator module is further configured to store the second input data based at least in part on the first input data.
9. A computer system configured to validate visual CAPTCHAs, the computer system comprising:
one or more hardware processors programmed, via executable code instructions, to:
generate a visual CAPTCHA including a plurality of visual patterns in a first configuration, wherein at least one of the visual patterns is configured to be manipulated by a human user to cause various amounts of overlapping of the visual patterns in order to produce different secondary images that are not visible in separate visual patterns of the plurality of visual patterns;
provide to the human user an indication of a target visual pattern to be created in a produced secondary image of the visual CAPTCHA;
receive input from the human user indicating a second overlapping configuration of the visual patterns that produces a moire pattern, wherein the moire pattern is configured to be perceived as including a first object by the human user viewing the moire pattern, and wherein an automated computer system analyzing the moire pattern cannot identify the first object;
compare the second overlapping configuration to a predetermined target overlapping configuration associated with the target visual pattern;
generate an indication of whether the second configuration was provided by a human based on said comparison; and
transmit the generated indication.
10. The computer system of claim 9, wherein the input from the human user is received based at least in part on interaction with a user interface.
11. The computer system of claim 10, wherein the user interface comprises an adjuster, and wherein the adjuster is movable to move one of the visual patterns in order to indicate the second overlapping configuration.
12. The computer system of claim 9, wherein the visual CAPTCHA comprises at least one of a vector image, scalable vector graphic, XML, graphics file, or an image file.
13. The computer system of claim 9, wherein the plurality of visual patterns comprises a first visual pattern, a second visual pattern, and a third visual pattern, wherein the first configuration corresponds to a non-overlapping configuration of the first visual pattern, the second visual pattern, and the third visual pattern, and wherein the second configuration corresponds to an overlapping configuration of the first visual pattern, the second visual pattern, and the third visual pattern.
14. The computer system of claim 9, wherein the visual CAPTCHA is configured for display as part of a website.
15. The computer system of claim 14, wherein the visual CAPTCHA is further configured to be fixed size, wherein rescaling a display including the visual CAPTCHA does not change a relative size of the visual CAPTCHA in the display.
16. The computer system of claim 9, wherein the visual CAPTCHA is configured to update after an elapsed time, and wherein a prompt is provided to the human user to manipulate the at least one of the visual patterns after the elapsed time.
17. Non-transitory computer storage comprising instructions for causing one or more computing devices to validate visual CAPTCHAs by:
generating a visual CAPTCHA including a plurality of visual patterns in a first configuration, wherein at least one of the visual patterns is configured to be manipulated by a human user to cause various amounts of overlapping of the visual patterns in order to produce different secondary images that are not visible in separate visual patterns of the plurality of visual patterns;
providing to the human user an indication of a target visual pattern to be created in a produced secondary image of the visual CAPTCHA;
receiving input from the human user indicating a second overlapping configuration of the visual patterns that produces a moire pattern, wherein the moire pattern is configured to be perceived as including a first object by the human user viewing the moire pattern, and wherein an automated computer system analyzing the moire pattern cannot identify the first object;
comparing the second overlapping configuration to a predetermined target overlapping configuration associated with the target visual pattern;
generating an indication of whether the second configuration was provided by a human based on said comparison; and
transmitting the generated indication.
18. The non-transitory computer storage of claim 17, wherein the input from the human user is received based at least in part on interaction with a user interface.
19. The non-transitory computer storage of claim 17, wherein the visual CAPTCHA is configured to update after an elapsed time, and wherein a prompt is provided to the human user to manipulate the at least one of the visual patterns after the elapsed time.
20. The non-transitory computer storage of claim 17, wherein the visual CAPTCHA is configured for display as part of a website.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

1. An electromagnetic radiation receiving method, comprising:
modeling at least one signal within an electromagnetic radiation band;
generating at least one digital reference signal corresponding to the modeled at least one signal;
converting the at least one digital reference signal to at least one corresponding analog reference signal, wherein at least a delay and a magnitude of the at least one corresponding analog reference signal are controllable;
combining a received waveform within the electromagnetic radiation band containing the at least one signal and an information carrier with the at least one corresponding analog reference signal in a first analog combiner to generate a first residue signal, at least the delay and magnitude of the at least one corresponding analog reference signal being controlled such that a magnitude of the at least one signal within the first residue signal is reduced with respect to the received waveform and the information carrier is substantially undistorted;
generating at least one cancellation signal, corresponding to a residue of the at least one signal in the residue signal, controllable with respect to at least waveform, magnitude and delay based on a feedback input;
combining the first residue signal with the at least one cancellation signal in a second combiner to generate a second residue signal; and
generating the feedback input based on at least the second residue signal to control said generating the at least one cancellation signal with respect to at least waveform, magnitude, and delay and, such that a magnitude of the at least one signal within the second residue signal is reduced with respect to the first residue signal and the information carrier is substantially undistorted.
2. The method according to claim 1, wherein the at least one cancellation signal is an analog signal generated based on a second digital reference signal.
3. The method of claim 2, further comprising:
(a) digitally correlating the second residue signal with the second digital reference signal; and
(b) using the time-averaged digital correlation output to provide the feedback input as an adaptive feedback control of at least one of the magnitude and delay of the at least one cancellation signal.
4. The method of claim 3, further comprising applying an iterative algorithm to adjust at least one of the magnitude and delay of the at least one cancellation signal, in order to reduce the time-averaged digital correlation output toward zero.
5. The method of claim 1, wherein the digital reference signal is provided by the source signal of an interference signal transmitter.
6. The method of claim 5, wherein the at least one corresponding analog reference signal comprises a linear combination of plurality of representations of a signal having respectively different magnitudes and delays.
7. The method according to claim 1, wherein the at least one signal comprises a multipath interference signal, and wherein the at least one corresponding analog reference signal comprises a plurality of representations of the digital reference signal differing in respective magnitude and delay.
8. The method of claim 1, further comprising digitizing the second residue signal using a superconducting analog to digital converter.
9. The method of claim 1, wherein the at least one cancellation signal is generated based on a digital lookup table which is adaptively updated.
10. The method of claim 1, further comprising a limiter which limits a power of the first residue signal before it reaches the second combiner.
11. The method of claim 1, wherein a dynamic range of the second residue signal with respect to a lowest information carrying amplitude of the information carrier is reduced with respect to the received waveform.
12. The method of claim 1, wherein the second combiner comprises a superconducting transformer having at least three coils.
13. The method according to claim 1, wherein second residue signal is reduced by at least 60 dB with respect to the at least one signal.
14. An electromagnetic radiation receiver, comprising:
at least one digital processor configured to model at least one signal within an electromagnetic radiation band and generating at least one digital reference signal corresponding to the modeled at least one signal, wherein at least a delay and a magnitude of the at least one corresponding analog reference signal are controllable;
an analog component configured to convert an output of the digital processor of the generated at least one digital reference signal to at least one corresponding analog reference signal;
a first analog combiner configured to combine a received waveform within the electromagnetic radiation band containing the at least one signal and an information carrier, with the at least one corresponding analog reference signal, to generate a first residue signal, at least the delay and magnitude of the at least one corresponding analog reference signal being controllable such that a magnitude of the at least one signal within the first residue signal is reduced with respect to the received waveform and the information carrier is substantially undistorted;
a second combiner configured to combine the first residue signal with at least one cancellation signal to generate a second residue signal; and
the at least one digital processor being further configured to generate the at least one cancellation signal, corresponding to a residue of the at least one signal in the residue signal, controlled with respect to at least waveform, magnitude and delay based on a feedback input from the second residue signal, such that a magnitude of the at least one signal within the second residue signal is reduced with respect to the first residue signal and the information carrier is substantially undistorted.
15. The system of claim 14, further comprising:
(a) a digital correlator configured to correlate the digitized second residue signal with the second digital reference signal; and
(b) the at least one digital processor further comprising an adaptive feedback control, configured to receive an output of the digital correlator, and to adjust at least one of the magnitude and delay of the at least one cancellation signal in dependence thereon.
16. The receiver of claim 15, wherein the at least one digital processor is further configured to perform an iterative algorithm to adjust at least one of the magnitude and delay of the at least one cancellation signal, in order to reduce toward zero a time-averaged digital output of the digital correlator.
17. The receiver according to claim 14, wherein the at least one signal comprises a multipath interference signal, and wherein the at least one digital processor generates at least one digital reference signal as a plurality of representations of a common digital reference signal differing in respective magnitude and delay.
18. The receiver of claim 14, further comprising a limiter configured to restrict at least a portion of a power of the coarse residue signal from the fine combiner when the power of the coarse residue signal exceeds a threshold, wherein the fine combiner comprises a superconducting transformer with at least three coils, and wherein the at least one digital processor comprises an adaptively updated a digital lookup table for generation of the at least one cancellation signal, wherein the digitizer comprises a superconducting analog to digital converter having a dynamic range, the dynamic range being insufficient to extract information from the information carrier, wherein the magnitude and delay of the digital reference signal and the at least one cancellation signal are adjusted such that the dynamic range of the digitizer is sufficient to detect the information from the information carrier in the second residue signal.
19. A receiver, comprising:
(a) an input configured to receive an analog signal comprising an information carrier and at least one signal within an electromagnetic radiation band;
(b) a first combiner configured to combine the analog signal with a first signal to produce a first combined signal with a reduced power of the at least one signal with respect to the input, substantially without distortion of the information carrier;
(c) a second combiner configured to combine the first combined signal, received by the second combiner substantially without introduction of intermodulation product of the analog signal and the first signal, with a second signal to produce a second combined signal with a reduced power of the at least one signal with respect to the first combined signal, substantially without distortion of the information carrier;
(d) a digitizer, configured to digitize the second combined signal while substantially retaining information corresponding to the information carrier; and
(e) a feedback controlled signal generator, configured to receive a representation of the digitized second combined signal, and control a generation of at least one of the first signal and the second signal.
20. The receiver of claim 19, further comprising at least one superconducting device selected from the group consisting of a digital processor, a digital correlator, an analog to digital converter, and a transformer.
21. The receiver of claim 19, wherein the feedback controlled signal generator comprises a digital correlator which is configured to determine a characteristic delay of the at least one signal, and to control a delay of a component of the second signal with respect to the characteristic delay to the at least one signal.