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Fast Algorithms for Phase DiversityBased Blind Deconvolution
, 1998
"... Phase diversity is a technique for obtaining estimates of both the object and the phase, by exploiting the simultaneous collection of two (or more) shortexposure optical images, one of which has been formed by further blurring the conventional image in some known fashion. This paper concerns a fast ..."
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Cited by 17 (4 self)
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Phase diversity is a technique for obtaining estimates of both the object and the phase, by exploiting the simultaneous collection of two (or more) shortexposure optical images, one of which has been formed by further blurring the conventional image in some known fashion. This paper concerns a fast computational algorithm based upon a regularized variant of the GaussNewton optimization method for phase diversitybased estimation when a Gaussian likelihood fittodata criterion is applied. Simulation studies are provided to demonstrate that the method is remarkably robust and numerically efficient. Keywords: phase diversity, blind deconvolution, phase retrieval, quasiNewton methods 1. INTRODUCTION Phase diversitybased blind deconvolution is a technique for obtaining estimates of both the object and the phase in optical image deblurring. It involves the simultaneous collection of two (or more) shortexposure images. One of these is the object that has been blurred by unknown aberra...
An Optical Model of Computation
 Theoretical Computer Science
, 2004
"... We prove computability and complexity results for an original model of computation called the continuous space machine. Our model is inspired by the theory of Fourier optics. We prove our model can simulate analog recurrent neural networks, thus establishing a lower bound on its computational power. ..."
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Cited by 14 (10 self)
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We prove computability and complexity results for an original model of computation called the continuous space machine. Our model is inspired by the theory of Fourier optics. We prove our model can simulate analog recurrent neural networks, thus establishing a lower bound on its computational power. We also define a \Theta (log_2 n) unordered search algorithm with our model.
Stanford Tech Report CTSR 200502 Light Field Photography with a Handheld Plenoptic Camera
"... This paper presents a camera that samples the 4D light field on its sensor in a single photographic exposure. This is achieved by inserting a microlens array between the sensor and main lens, creating a plenoptic camera. Each microlens measures not just the total amount of light deposited at that lo ..."
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Cited by 3 (0 self)
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This paper presents a camera that samples the 4D light field on its sensor in a single photographic exposure. This is achieved by inserting a microlens array between the sensor and main lens, creating a plenoptic camera. Each microlens measures not just the total amount of light deposited at that location, but how much light arrives along each ray. By resorting the measured rays of light to where they would have terminated in slightly different, synthetic cameras, we can compute sharp photographs focused at different depths. We show that a linear increase in the resolution of images under each microlens results in a linear increase in the sharpness of the refocused photographs. This property allows us to extend the depth of field of the camera without reducing the aperture, enabling shorter exposures and lower image noise. Especially in the macrophotography regime, we demonstrate that we can also compute synthetic photographs from a range of different viewpoints. These capabilities argue for a different strategy in designing photographic imaging systems. To the photographer, the plenoptic camera operates exactly like an ordinary handheld camera. We have used our prototype to take hundreds of light field photographs, and we present examples of portraits, highspeed action and macro closeups.
Electronic design issues in highbandwidth parallel optical interfaces to VLSI circuits
, 1999
"... ...................................................................................................................................... viii List of publications .......................................................................................................................ix Chapter 1: Introd ..."
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Cited by 2 (1 self)
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...................................................................................................................................... viii List of publications .......................................................................................................................ix Chapter 1: Introduction..................................................................................................................1 1.1 Scope and overall research contribution..............................................................................1 1.2 Motivation............................................................................................................................2 1.2.1 The interconnect problem .............................................................................................2 1.2.2 Capabilities and limitations of electrical interconnects................................................4 1.2.3 Advantages of optical interconnects ......................................
Optical processor for solving the traveling salesman problem (TSP
 Proc. of SPIE, Optical Information Systems IV, volume 63110G
, 2006
"... This paper introduces an optical solution to (boundedlength input instances of) an NPcomplete problem called the traveling salesman problem using a pure optical system. The solution is based on the multiplication of a binarymatrix, representing all feasible routes, by a weightvector, representin ..."
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Cited by 2 (0 self)
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This paper introduces an optical solution to (boundedlength input instances of) an NPcomplete problem called the traveling salesman problem using a pure optical system. The solution is based on the multiplication of a binarymatrix, representing all feasible routes, by a weightvector, representing the weights of the problem. The multiplication of the binarymatrix by the weightvector can be implemented by any optical vectormatrix multiplier. In this paper, we show that this multiplication can be obtained by an optical correlator. In order to synthesize the binarymatrix, a unique iterative algorithm is presented. This algorithm synthesizes an Nnode binarymatrix using rather small number of vector duplications from the (N−1)node binarymatrix. We also show that the algorithm itself can be implemented optically and thus we ensure the entire optical solution to the problem. Simulation and experimental results prove the validity of the optical method.
PRACTICAL COMPRESSIVE SENSING OF LARGE IMAGES
"... Compressive imaging (CI) is a natural branch of compressed sensing (CS). One of the main difficulties in implementing CI is that, unlike many other CS applications, it involves huge amount of data. This data load has extensive implications for the complexity of the optical design, for the complexity ..."
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Cited by 1 (1 self)
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Compressive imaging (CI) is a natural branch of compressed sensing (CS). One of the main difficulties in implementing CI is that, unlike many other CS applications, it involves huge amount of data. This data load has extensive implications for the complexity of the optical design, for the complexity of calibration, for data storage requirements. As a result, practical CI implementations are mostly limited to relative small image sizes. Recently we have shown that it is possible to overcome these problems by using a separable imaging operator. We have demonstrated that separable imaging operator permits CI of megapixel size images and we derived a theoretical bound for oversampling factor requirements. Here we further elaborate the tradeoff of using separable imaging operator, present and discuss additional experimental results.
An AutoFocusing Method in a Microscopic Testbed for Optical Discs
, 2000
"... this paper. Key words: autofocus; disc testbed; optical discs; standard deviation. Accepted: July 20, 2000 Available online: http://www.nist.gov/jres 1. Introduction In an optical vision system, an autofocusing element plays an important role. An objective lens collects light from the object ..."
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this paper. Key words: autofocus; disc testbed; optical discs; standard deviation. Accepted: July 20, 2000 Available online: http://www.nist.gov/jres 1. Introduction In an optical vision system, an autofocusing element plays an important role. An objective lens collects light from the object and makes a clear image at the focal plane if the distance between the object and the objective lens is perfectly controlled to meet the focusing condition. A feedback signal is always needed for the controlling system. There are many kinds of feedback signal that can be used for this purpose in different systems. For example, an astigmatic field lens and a quaddetector (hardware) are used to create a focusing feedback signal in Compact Disc (CD) drives [1]. For digital image signals grabbed via a CCD camera, the feedback signal for autofocusing can be extracted from the image itself by software using Fourier transforms [2]. Ac
SPL063332008.R1 1 Compressed Imaging with a Separable Sensing Operator
"... Abstract — Compressive imaging (CI) is a natural branch of compressed sensing (CS). Although a number of CI implementations have started to appear, the design of efficient CI system still remains a challenging problem. One of the main difficulties in implementing CI is that it involves huge amounts ..."
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Abstract — Compressive imaging (CI) is a natural branch of compressed sensing (CS). Although a number of CI implementations have started to appear, the design of efficient CI system still remains a challenging problem. One of the main difficulties in implementing CI is that it involves huge amounts of data, which has farreaching implications for the complexity of the optical design, calibration, data storage and computational burden. In this paper, we solve these problems by using a twodimensional separable sensing operator. By so doing, we reduce the complexity by factor of 10 6 for megapixel images. We show that applying this method requires only a reasonable amount of additional samples.
BioMedical Engineering OnLine BioMed Central
, 2006
"... Quantitative phase imaging with scanning holographic microscopy: an experimental assesment ..."
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Quantitative phase imaging with scanning holographic microscopy: an experimental assesment