摘要:
An optical emitter and an optical sensor are arranged at locations in a scene. A physical mask is arranged between the emitter and sensor to modulate directional electromagnetic signals from the emitter spatially. The modulated signals are analyzed to determine geometric properties at the location in the scene.
摘要:
A system measures reflectance in a scene. A first optical sensor is configured to measure incident energy at a location in a scene. A second optical sensor is configured to measure reflected energy from the location in the scene. The incident energy and the reflected energy are analyzed to determine a photometric property at the location of the scene.
摘要:
An optical receiver is arranged at a location in a scene. The optical receiver includes a photo sensor configured to detect spatio-temporal modulated optical signals directed at the scene from a set of spatially dispersed optical transmitters, and to convert the optical signals from each of the optical transmitters to a corresponding electronic signal. The electronic signals can be analyzed to determine geometric properties of the location in the scene.
摘要:
An optical receiver is arranged at a location in a scene. The optical receiver includes a photo sensor configured to detect spatio-temporal modulated optical signals directed at the scene from a set of spatially dispersed optical transmitters, and to convert the optical signals from each of the optical transmitters to a corresponding electronic signal. The electronic signals can be analyzed to determine geometric properties of the location in the scene.
摘要:
In illustrative implementations of this invention, an imaging system includes multiple light sources that illuminate a scene, and also includes a lock-in time of flight camera. While the scene is illuminated by these light sources, each of the light sources is amplitude-modulated by a different modulation pattern, and a reference signal is applied to the lock-in time-of-flight camera. The modulation patterns and the reference signal are carefully chosen such that the imaging system is able to disentangle, in real time, the respective contributions of the different light sources, and to compute, in real-time, depth of the scene. In some cases, the modulation signals for the light sources are orthogonal to each other and the reference signal is broadband. In some cases, the modulation codes for the light sources and the reference code are optimal codes that are determined by an optimization algorithm.
摘要:
In exemplary implementations of this invention, a light field camera uses a light field dictionary to reconstruct a 4D light field from a single photograph. The light field includes both angular and spatial information and has a spatial resolution equal to the spatial resolution of the imaging sensor. Light from a scene passes through a coded spatial light modulator (SLM) before reaching an imaging sensor. Computer processors reconstruct a light field. This reconstruction includes computing a sparse or compressible coefficient vector using a light field dictionary matrix. Each column vector of the dictionary matrix is a light field atom. These light field atoms each, respectively, comprise information about a small 4D region of a light field. Reconstruction quality may be improved by using an SLM that is as orthogonal as possible to the dictionary.
摘要:
A time-of-flight camera images an object around a corner or through a diffuser. In the case of imaging around a corner, light from a hidden target object reflects off a diffuse surface and travels to the camera. Points on the diffuse surface function as a virtual sensors. In the case of imaging through a diffuser, light from the target object is transmitted through a diffusive media and travels to the camera. Points on a surface of the diffuse media that is visible to the camera function as virtual sensors. In both cases, a computer represents phase and intensity measurements taken by the camera as a system of linear equations and solves a linear inverse problem to (i) recover an image of the target object; or (ii) to compute a 3D position for each point in a set of points on an exterior surface of the target object.
摘要:
In illustrative implementations of this invention, light sources illuminate a surface with multi-spectral, multi-directional illumination that varies in direction, wavelength, coherence and collimation. One or more cameras capture images of the surface while the surface is illuminated under different lighting conditions. One or more computers take, as input, data indicative of or derived from the images, and determine a classification of the surface. Based on the computed classification, the computers output signals to control an I/O device, such that content displayed by the I/O device depends, at least in part, on the computed classification. In illustrative implementations, this invention accurately classifies a wide range of surfaces, including transparent surfaces, specular surfaces, and surfaces with few features.
摘要:
In illustrative implementations of this invention, an imaging system includes multiple light sources that illuminate a scene, and also includes a lock-in time of flight camera. While the scene is illuminated by these light sources, each of the light sources is amplitude-modulated by a different modulation pattern, and a reference signal is applied to the lock-in time-of-flight camera. The modulation patterns and the reference signal are carefully chosen such that the imaging system is able to disentangle, in real time, the respective contributions of the different light sources, and to compute, in real-time, depth of the scene. In some cases, the modulation signals for the light sources are orthogonal to each other and the reference signal is broadband. In some cases, the modulation codes for the light sources and the reference code are optimal codes that are determined by an optimization algorithm.
摘要:
In exemplary implementations, this invention comprises apparatus for retinal self-imaging. Visual stimuli help the user self-align his eye with a camera. Bi-ocular coupling induces the test eye to rotate into different positions. As the test eye rotates, a video is captured of different areas of the retina. Computational photography methods process this video into a mosaiced image of a large area of the retina. An LED is pressed against the skin near the eye, to provide indirect, diffuse illumination of the retina. The camera has a wide field of view, and can image part of the retina even when the eye is off-axis (when the eye's pupillary axis and camera's optical axis are not aligned). Alternately, the retina is illuminated directly through the pupil, and different parts of a large lens are used to image different parts of the retina. Alternately, a plenoptic camera is used for retinal imaging.