摘要:
A method for providing spectral and temporal stealthy information transmitted over an optical communication channel, according to which, at the transmitting side, the power spectral density of a pulse sequence bearing the information is reduced by encrypting the temporal phase of the pulse sequence. The power of the pulse sequence is spread in the frequency domain, to be below the noise level, by sampling the pulse sequence. Spectral phase encoding is used to temporally spread the pulse sequence and to prevent coherent addition of its spectral replicas in frequency domain. The resulting signal, encrypted both in time and frequency domains, is then transmitted. Spectral phase decoding is performed at the receiving side by performing coherent detection and folding all the spectral replicas of the transmitted signal to the baseband by means of sampling. The temporal phase of the signal is decrypted and the information which is delivered by the pulse sequence is decoded.
摘要:
A phase-adjusting element configured to provide substantially liquid-invariant extended depth of field for an associated optical lens. One example of a lens incorporating the phase-adjusting element includes the lens having surface with a modulated relief defining a plurality of regions including a first region and a second region, the first region having a depth relative to the second region, and a plurality of nanostructures formed in the first region. The depth of the first region and a spacing between adjacent nanostructures of the plurality of nanostructures is selected to provide a selected average index of refraction of the first region, and the spacing between adjacent nanostructures of the plurality of nanostructures is sufficiently small that the first region does not substantially diffract visible light.
摘要:
A system, apparatus and method of performing 3-D object profile inter-planar estimation and/or range inter-planar estimation of objects within a scene, including: providing a predefined finite set of distinct types of features, resulting in feature types, each feature type being distinguishable according to a unique bi-dimensional formation; providing a coded light pattern having multiple appearances of the feature types; projecting the coded light pattern, having axially varying intensity, on objects within a scene, the scene having at least two planes, resulting in a first plane and a second plane; capturing a 2-D image of the objects having the projected coded light pattern projected thereupon, resulting in a captured 2-D image, the captured 2-D image including reflected feature types; determining intensity values of the 2-D captured image; and performing 3-D object profile inter-planar estimation and/or range inter-planar estimation of objects within the scene based on determined intensity values.
摘要:
The present invention provides a system for imaging an object comprising: an optical imaging unit for imaging an object on a detection array, the optical imaging unit defining an optical axis and comprising a multicore fiber configured to collect light from the object at an input edge of the multicore fiber and transfer collected light to an output edge of the multicore fiber; a displacing unit configured to shift the input edge of the multicore fiber relatively to the object in a plane substantially perpendicular to the optical axis to obtain a set of shifted images of the object; and an operating unit configured to operate the displacing unit by setting a shifting amplitude to either a first amplitude inferior or equal to the diameter of a core of the multicore fiber or a second amplitude superior or equal to the diameter of the multicore fiber.
摘要:
A sensory substitution device (SSD) for providing a person with neural signals responsive to features of an environment, the SSD comprising: at least one camera that acquires an image of the environment; and at least one corneal neural stimulator that stimulates nerve endings in the cornea of an eye of the person to generate neural signals responsive to the image that propagate to the person's brain.
摘要:
Apparatus (20) for 3D mapping of an object (28) includes an illumination assembly (30), including a coherent light source (32) and a diffuser (33), which are arranged to project a primary speckle pattern on the object. A single image capture assembly (38) is arranged to capture images of the primary speckle pattern on the object from a single, fixed location and angle relative to the illumination assembly. A processor (24) is coupled to process the images of the primary speckle pattern captured at the single, fixed angle so as to derive a 3D map of the object.
摘要:
A method of optical element manufacturing, the method may include selecting a range of a misfocus parameter ψ; and designing the optical element to comprise multiple regions, wherein the optical transfer function (OTF) of the optical element allows, for the range of the misfocus parameter ψ, transmission of images with a contrast of at least 10% for all normalized spatial frequencies up to 50% of a theoretical maximum that is attainable with a full aperture in an in-focus condition.
摘要:
An imaging arrangement and method for extended the depth of focus are provided. The imaging arrangement comprises an imaging lens having a certain affective aperture, and an optical element associated with said imaging lens. The optical element is configured as a phase-affecting, non-diffractive optical element defining a spatially low frequency phase transition. The optical element and the imaging lens define a predetermined pattern formed by spaced-apart substantially optically transparent features of different optical properties. Position of at least one phase transition region of the optical element within the imaging lens plane is determined by at least a dimension of said affective aperture.
摘要:
An imaging system is presented for use in multi-range imaging of an object scene by incoherent light. The imaging system comprises aligned a phase mask section, a single focus lens section, and a pixel detector array (PDA). The phase mask section has a generally non-diffractive, narrowly bounded, phase variation corresponding to a profile of a through-object Modulated Transfer Function (MTF) of the imaging system, where the profile has, at an at least one non-zero spatial frequency, at least two regions of growth leading to the MTF higher than 10%.
摘要:
An image projecting device and method are presented. The device comprises a light source system operable to produce a light beam to impinge onto an active surface of a spatial light modulator (SLM) unit formed by an SLM pixel arrangement; and a magnification optics accommodated at the output side of the SLM unit. The light beam impinging onto the SLM pixel arrangement has a predetermined cross section corresponding to the size of said active surface. The SLM unit comprises first and second lens' arrays at opposite sides of the pixel arrangement, such that each lens in the first array and a respective opposite lens in the second array are associated with a corresponding one of the SLM pixels