A collimator for a detector is disclosed. The collimator comprises: a bottom plate provided with imaging through holes distributed in an array, each of the imaging through holes comprising a first hole segment and a second hole segment, the transverse size of the first hole segment gradually decreasing in a direction from a free end to the second hole segment, and the transverse size of the second hole segment gradually decreasing in a direction from the free end to the first hole segment; a shielding case formed on the bottom plate; and a top plate disposed in the shielding case and closing at least a part of an opening of the shielding case, the top plate being provided with shielding through holes distributed in an array, and the imaging through holes being in one-to-one correspondence with the shielding through holes.

Disclosed herein is an image sensor comprising: a plurality of radiation detectors; a mask with a plurality of radiation transmitting zones and a radiation blocking zone; and an actuator configured to move the plurality of radiation detectors from a first position to a second position and to move the mask from a third position to a fourth position; wherein while the radiation detectors are at the first position and the mask is at the third position and while the radiation detectors are at the second position and the mask is at the fourth position, the radiation blocking zone blocks radiation from a radiation source that would otherwise incident on a dead zone of the image sensor and the radiation transmitting zones allow at least a portion of radiation from the radiation source that would incident on active areas of the image sensor to pass through.

An imager unit and computerized tomography system are disclosed. The imager unit comprises a radiation source unit comprising at least one radiation source emitting selected radiation and configured to provide diffused radiation with general direction of propagation, and an image collection unit comprising aperture unit and detector array located downstream of the aperture unit with respect to said general direction of propagation. The aperture unit comprises a set of two or more aperture arrays each aperture array having a predetermined arrangement of apertures. The aperture unit is configured for utilizing said set of aperture arrays for collecting the radiation during corresponding collection time periods.

A mask for use in compressed sensing of incoming radiation, the mask comprising: a body formed of a material that modulates an intensity of incoming radiation of interest. The body has a plurality of mask aperture regions, each comprising at least one mask aperture that allows a higher transmission of the radiation relative to other portions of the respective mask aperture region, the relative transmission being sufficient to allow reconstruction of the compressed sensing measurements; the mask has one or more axes of rotational symmetry with respect to the mask aperture regions; the mask apertures have a shape that provides symmetry after a rotation about the one or more axes of rotational symmetry; and mutual coherence of a sensing matrix generated by the rotation of the respective mask aperture regions is less than one. An imaging system for compressed sensing of incoming radiation comprising such a mask is also provided.

A method includes forming a first image of a scene through a static coded aperture onto a sensor with the static coded aperture in a first position relative to the sensor, shifting the coded aperture to a second position relative to the sensor, and forming a second image of the scene through the static coded aperture onto the sensor with the static coded aperture in the second position. Two or more images can be formed in this way. The method includes forming a combined image by deconvolving the two or more images and combining data from the two or more images into the combined image. The combined image can be a more accurate representation of the scene than either of the first and second images.

A radiation imaging system images a distributed source of radiation from an unknown direction by rotating a scatter mask around a central axis. The scatter mask has a pixelated outer surface of tangentially oriented, flat geometric surfaces that are spherically varying in radial dimension that corresponds to a discrete amount of attenuation. Rotation position of the scatter mask is tracked as a function of time. Radiation counts from gamma and/or neutron radiation are received from at least one radiation detector that is positioned at or near the central axis. A rotation-angle dependent detector response curve (DRC) is generated based on the received radiation counts. A reconstruction algorithm for distributed radiation source(s) and/or localized source(s) are applied based on the tracked rotation position and prior characterization of the detector response for a given scatter mask. A two-dimensional image with relative orientation and source distribution is generated from the measured DRC.

To provide a technique with which it is possible to make collimator plates resistant to deformation, and reduce position offsets in the collimator plates, a collimator module (1) comprises a plurality of collimator plate sets (2) lined up side by side in a channel direction (CH), wherein each collimator plate set (2) comprises a first collimator plate (3), a second collimator plate (4), and a joint layer (5) disposed between the first collimator plate (3) and second collimator plate (4) for adhesively bonding the first collimator plate (3) and second collimator plate (4) together, and the plurality of collimator plate sets (2) are lined up side by side in the channel direction (CH) with an air layer (20) intervening between adjacent two of the plurality of collimator plate sets (2).

An imaging system includes a first mask unit having a hollow cavity surrounding a rotational axis. The first mask unit is characterized by a first pattern encoded on its surface. The first pattern defines a height along an axial direction and includes a respective plurality of elements with at least one open element and at least one blocking element in each of the axial direction and the circumferential direction. A detector is configured to receive radiation data from at least one source such that one of the detector and the source is located inside the hollow cavity and another is located outside the hollow cavity. The first mask unit is configured to move relative to the rotational axis in at least one of the axial and circumferential direction until the first pattern is recorded in 360 degrees. A second mask unit may be positioned around the first mask unit.

In an embodiment, an X-ray imaging apparatus includes an X-ray radiation source to emit X-ray radiation, an object to be sampled being within a receiving region; a converter for spatially resolved conversion of X-ray radiation, after passing through the receiving region, into visible light; a detector, to emit a detector signal based upon visible light from the converter registered by the detector; a pattern generator, to realize a large number of light and shadow patterns (LSPs) in a time-staggered manner by acting on visible light generated by the converter, respective detector signals being generated based upon respective LSPs; and at least one processor, to generate the image of the object based upon the detector signals generated and an item of information about the LSPs. The pattern generator device is configured to generate the large number of LSPs by at least one of overriding and partial shadowing of the visible light.

A coded aperture mask is provided. The coded aperture mask may include a 2-D planar substrate having a plurality of holes constructed based on a Cartesian product of a first 1-D aperture set and a second 1-D aperture set. The first 1-D aperture set may have a first balanced decoder. The second 1-D aperture set may have a second balanced decoder. The Cartesian product may involve the first 1-D aperture set and the second 1-D aperture set arranged in a non-zero angle (e.g., 90 degrees) to each other. The first 1-D aperture set may define a first axis of the 2-D planar substrate. The second 1-D aperture set may define a second axis of the 2-D planar substrate. The plurality of holes on the 2-D planar substrate may correspond to holes in both of the first 1-D aperture set and the second 1-D aperture set.