X-ray apparatus with folded field of view

Abstract

The X-ray apparatus includes an X-ray source, a scintillator, a single mirror, and a camera. The camera has a field of view centered on the camera's optical axis. The single mirror completely encompasses the field of view, as the field of view is folded back toward the scintillator by the single mirror. The single mirror is positioned at an angle to a plane perpendicular to the optical axis at the point where the optical axis intersects the single mirror. The angle is reduced from 45 degrees to reduce the volume of the camera's folded field of view. The angle is greater than or equal to the threshold angle that prevents triple specular reflection of light between the single mirror and the scintillator.

Description

[Technical Field]

[0001] This invention relates to an X-ray apparatus. [Background technology]

[0002] X-ray equipment, such as computed tomography (CT) scanners, is sometimes used to detect defects and / or damage in an object without disassembling it. However, current X-ray detection equipment is in need of improvement because it is prohibitively expensive for certain analyses, too large or bulky for use in certain situations, and incapable of forming images of the interior of an object with adequate resolution, and also due to other problems known in the art. Solutions to these problems, and other problems known in the art, are specified herein. [Overview of the project]

[0003] X-ray equipment that creates a three-dimensional (3D) reconstructed image of a scanning target can be large and bulky due to requirements regarding the optical path length of the light used to image the scanning target. However, the size of X-ray equipment with separate detectors, for example, equipment with a non-shortest path length between the scanning target and the detector, can be reduced by using folding mirrors, for example, by using mirrors angled relative to other components of the X-ray equipment, to reduce the dimensions of the X-ray equipment to be smaller than the optical path length. Folding mirrors "fold" the camera's field of view within the X-ray equipment so that the camera can receive "off-axis" light, for example, light that is not parallel to the camera's optical axis but does not coincide with it. Generally, the smaller the "folded" field of view, the smaller the X-ray equipment can be.

[0004] However, problems arise when optimizing the internal geometry of an X-ray apparatus for the smallest possible folded field of view. For example, determining the relative orientation of the scintillator, mirror, and camera to minimize the folded field of view can result in the orientation and / or position of the scintillator, mirror, and camera when light from the scintillator is reflected by the mirror, then back to the scintillator, and then to the camera. The camera may mistakenly identify the light reflected from the scintillator (e.g., triple reflection between the mirror and the scintillator) as light that traveled directly from the scintillator to the mirror, and then directly from the mirror to the camera, which can lead to errors in 3D reconstruction.

[0005] This disclosure further describes structural constraints on X-ray equipment to minimize the size of the detection subsystem in the X-ray equipment while avoiding triple reflection. Accordingly, this disclosure aims to balance the advantages and disadvantages of reducing the size of the detection subsystem, including the scintillator, mirror, and camera, in the X-ray equipment.

[0006] In general, innovative embodiments of the subject matter described herein can be embodied in an X-ray apparatus including an X-ray source configured to emit X-rays, a scintillator configured to absorb X-rays after interaction with an object placed in the X-ray apparatus at a first surface of the scintillator and to emit light from a second surface of the scintillator in response to the absorption of X-rays, a single mirror positioned to reflect the light from the second surface of the scintillator toward the camera, and a camera positioned to receive the light reflected from the single mirror. The camera may have a field of view centered on the optical axis of the camera. The single mirror can be large enough to completely encompass the field of view, as the field of view is folded toward the scintillator by the single mirror. The single mirror can be positioned at an angle to a plane that is perpendicular to the optical axis at the point where the optical axis intersects the single mirror. The angle can be reduced from 45 degrees to reduce the volume of the folded field of view of the camera. The angle can be greater than or equal to the threshold angle that prevents triple specular reflection of light between the single mirror and the scintillator, and the threshold angle is set according to (i) a first distance along the optical axis between the camera and the scintillator, (ii) a second distance along the optical axis between the single mirror and the scintillator, and (iii) the size of the scintillator.

[0007] These and other implementations may each optionally include one or more of the following features:

[0008] In some implementations, the angle of a single mirror relative to the plane is smaller than a further threshold angle that prevents a combination of double specular reflection of light at the single mirror and single diffuse reflection of light at the scintillator.

[0009] In some implementations, the angle of a single mirror relative to the plane is greater than the further threshold angle that prevents a combination of double specular reflection of light at the single mirror and single diffuse reflection of light at the scintillator.

[0010] In some implementations, the bounding box volume of the folded field of view of the camera is 78% of the bounding box volume of the unfolded field of view of the camera.

[0011] In some implementations, the camera's field of view is 20 x 31 square degrees.

[0012] In some implementations, the X-ray apparatus further includes a shroud positioned to prevent stray light from affecting the camera.

[0013] In some implementations, the shroud is positioned between the X-ray source and the camera.

[0014] In some implementations, the X-ray apparatus further includes a motion system for moving the camera, the subject, or both during scanning.

[0015] In some implementations, the system includes an X-ray device and a computer programmed to execute algorithms for performing a three-dimensional reconstruction of the subject using data generated by light received by a camera.

[0016] Certain embodiments of the subject matter described herein can be implemented to achieve one or more of the following advantages: In some implementations, false bright or dark spots that do not represent the scanning target can be avoided, thereby improving the 3D reconstruction of the scanning target. Generally, artifacts (e.g., bright spots) that would normally appear in one or more radiographs acquired by the camera can be reduced (or completely avoided), thereby preventing errors from being added to the reconstructed volume of the scanning target, and on the other hand, the size of the detector assembly can be reduced, and optionally the size of the X-ray apparatus including the detector assembly can be reduced. In some implementations, all dimensions of the detection subsystem can be shorter than the optical path length of light traveling inside the detection subsystem.

Brief Description of the Drawings

[0017] [Figure 1] It is a diagram depicting an example of an X-ray device. [Figure 2A] It is a diagram depicting an example of a detection subsystem including a scintillator, a mirror, and a camera of an X-ray device that generates specular triple reflection. [Figure 2B] It is a diagram depicting an unfolded view of the detection subsystem of FIG. 2A that is adjustable to create a configuration for preventing specular triple reflection. [Figure 2C] It is a diagram depicting an unfolded view of a detection subsystem that prevents specular triple reflection. [Figure 3A] It is a diagram depicting an example of a detection subsystem including a scintillator, a mirror, and a camera of an X-ray device that is adjustable to create a configuration for allowing diffuse triple reflection. [Figure 3B] It is a diagram depicting an unfolded view of a detection subsystem that prevents both specular triple reflection and diffuse triple reflection.

Modes for Carrying Out the Invention

[0018] FIG. 1 depicts an example of an X-ray device 100. The X-ray device 100 includes an X-ray source 101 configured to radiate X-rays 102 toward a scintillator 103. When the X-rays 102 pass through a scanning target 107 and collide with the scintillator 103, the scintillator 103 may radiate light 108. A single mirror 104 reflects the light 108 toward a camera 105. By using a mirror to guide the light radiated by the scintillator 103 to the camera 105, the positioning of the camera 105 can be achieved outside the primary beam of the X-ray radiation 102, thereby reducing the chance that the X-ray radiation will damage the camera 105, and thus improving the lifespan and performance of the camera 105.

[0019] The X-ray source 101 is a device that emits X-ray radiation. The scintillator 103 may include a material that emits visible light, ultraviolet light, and / or infrared light when excited by X-ray radiation. The camera 105 may be a device or apparatus configured to detect visible light, ultraviolet light, or infrared light. In some implementations, the X-ray apparatus 100 includes a motion system 106 configured to move, reposition, maneuver, or otherwise operate the camera 105 and / or scanning target 107 relative to the X-ray source 101 (for example, in some implementations, the X-ray source 101 can be moved).

[0020] Mount 113 supports the scintillator 103, mirror 104, and camera 105. The enclosure 111 surrounds not only the X-ray source 101, scintillator 103, mirror 104, camera 105, motion system 106, scanning target 107, and mount 113, but also other components of the X-ray apparatus 100.

[0021] In some implementations, camera 105 includes an optical camera, a charge-coupled device (CCD) camera, a photodiode, or any combination thereof. For example, the optical camera may include a complementary metal-oxide-semiconductor (CMOS) digital camera sensor. Alternatively or additionally, the optical camera may include a red-green-green-blue (RGGB) Bayer filter and / or a monochromatic optical camera. In some examples, the optical camera may include a back-illuminated sensor and / or a front-illuminated sensor. In the examples, camera 105 may be configured to detect infrared light, ultraviolet light, and / or visible light 108.

[0022] In some implementations, the camera 105 is positioned on the opposite side of the scintillator 103 and shroud 110 from the X-ray source 101, so that the shroud 110 blocks and protects the camera 105 from stray visible light and / or X-rays 102 emitted from the X-ray source 101. The shroud 110 can be a cover that prevents visible light, ultraviolet light, and / or infrared light from reaching the camera 105. Stray light is visible light, infrared light, and / or ultraviolet light that adversely affects the camera by introducing noise that exceeds the camera's readout noise.

[0023] The camera 105 is oriented at an angle to the y-axis, which can help reduce the size of the detection subsystem, which includes a scintillator 103, a mirror 104, and the camera 105. The size of the detection subsystem (or the field of view of the camera included in the detector assembly) can refer to dimensions along the horizontal or vertical direction, e.g., dimensions along the X or Y direction, or both horizontal and vertical and depth dimensions, e.g., X and Y areas, or any one of the three spatial directions, e.g., X, Y, and Z volumes. The camera 105, angled relative to the scintillator 103, can result in a type of optical path where light emitted by the scintillator is reflected twice by the mirror 104 before entering the camera 105. This type of optical path is called "triple reflection" because the light is reflected three times (twice by the mirror 104 and once by the scintillator 103) before the camera 105 receives the triple-reflected light.

[0024] In some implementations, triple-reflected light in an X-ray apparatus can cause problems during the three-dimensional (3D) reconstruction of the scanning target 107. For example, the X-ray apparatus 100 may include a computer 109 configured to receive data from a camera 105. The computer 109 may be one or more computers integrated with the camera 105, included in the detector assembly of the X-ray apparatus 101, and / or located far away from the X-ray apparatus 101 (e.g., in a server farm) and coupled to communicate with the X-ray apparatus 101, for example, via the internet.

[0025] Camera 105 can be configured to generate data (e.g., radiographs) using the detected light. In some implementations, the data includes the intensity and wavelength of light for each pixel. Computer 109 can be configured to run an algorithm for 3D construction using the data (and optionally known information about the geometry of the components of scintillator 103, mirror 104, and camera 105) to reconstruct a 3D model of the scanning target 107 based on the light produced by scintillator 103. By mapping the locations where specific rays are produced on scintillator 103 to pixel locations or voxel locations relative to the 3D image, computer 109 can associate orientation, e.g., the direction of the rays, with respect to the light entering camera 105. In some implementations, the algorithm can estimate that the light reaching camera 105 has undergone only one reflection at mirror 104 along the optical path from scintillator 103 to camera 105, and optionally this information can be used to facilitate 3D reconstruction. Therefore, by carefully selecting the size, position, and orientation of the scintillator 103, mirror 104, and camera 105 in the detector assembly, triple reflections can be avoided, so that the algorithm can perform an improved 3D reconstruction of the scanning target 107 from the acquired data (e.g., radiographs). It should be noted that the triple reflections to be avoided may include specular or diffuse reflections at the scintillator 103.

[0026] Figure 2A depicts an example of a detection subsystem 200a including a scintillator 103, a mirror 104, and a camera 105 that generate a specular triple reflection. For example, the entire optical path including the triple reflection may include optical paths 201, 202, 203, and 204. The light generated by the scintillator 103 can propagate at any angle between 0 and 180° when measured from the +Y direction in a counterclockwise direction. This particular example follows the optical path 201 of the light generated by the scintillator 103. When the light traveling along optical path 201 encounters the mirror 104, the light undergoes specular reflection. In this disclosure, specular reflection refers to reflection when the angle of incidence is equal to the angle of reflection. Thus, the angle of reflection at the mirror 104 is determined by the direction of the optical path 201 and the orientation of the mirror 104.

[0027] After the first reflection 205, the light continues along the optical path 202 toward the scintillator 103. The light undergoes a second reflection 206, which can be specular or diffuse, for example, on the scintillator 103, where the angle of incidence is not equal to the angle of reflection. In this example, the second reflection 206 is specular, thereby causing the light to travel along the optical path 203 toward the mirror 104. The light undergoes a third reflection 207 on the mirror 104 and then travels toward the camera 105. Such triple reflections can create artifacts that interfere with 3D reconstruction. In some implementations, artifacts occur when pixels or voxels are mapped to two different locations in space because some light arrives via a single reflection and some light arrives via triple reflection.

[0028] Triple reflection reaches only camera 105 under certain geometric conditions. The arrangement and dimensions of scintillator 103 can be selected from a wide range of options as required for a particular implementation. The parameters of scintillator 103, e.g., size, orientation, and location, depend on the size of the scanning target 107 and the desired resolution of the 3D model created by 3D reconstruction. Given a specific scintillator size, the position and orientation of scintillator 103, the size, position, and orientation of mirror 104 and camera 105 are determined by the present invention to reduce (or minimize) the size of the folded field of view of camera 105, and therefore the size of the detector assembly 200a, and on the other hand, to further reduce (or eliminate) the imaging of artifacts that would be caused by triple reflection.

[0029] The angle θ can determine the orientation of the mirror 104 relative to the camera 105. The angle θ is the angle between the reflective surface of the mirror 104 and a plane 208 perpendicular to the optical axis 209 of the camera 105. Note that if the optical axis 209 is parallel to the scintillator 103 and the angle θ is 45 degrees, triple reflection cannot occur, but the folded field of view of the camera 105 should still occupy a considerable amount of space in the X-ray apparatus 100. Reducing the angle θ from 45 degrees reduces the volume of the folded field of view of the camera 105 (and therefore the volume of the detection subsystem), but the angle θ should not be reduced to such an extent that triple specular reflection can occur, as depicted in Figure 2A.

[0030] The field of view of camera 105 determines which light emitted by scintillator 103 reaches camera 105. In this example, the camera's field of view corresponds to points A, D, and E. Point A is the focal point of camera 105, e.g., the apex of the camera's field of view cone. In some implementations, points D and E are the edges of scintillator 103, so the distance between points D and E is the length of the scintillator. This means that none of the scintillator 103 exists outside the field of view of camera 105, and no part of the camera's field of view is wasted by containing anything other than the scintillator 103.

[0031] In Figure 2A, the field of view is folded by the mirror 104. In other words, the volume of the space containing the camera's field of view is reduced by the presence of the mirror 104, so the volume of the folded field of view is smaller than the volume of the unfolded field of view. For example, the volume of the field of view can be described as a bounding box, and the dimensions of the bounding box are determined by the size of the field of view between the camera 105, the mirror 104, and the scintillator 103. The bounding box can be the smallest rectangular volume required to encompass the entire field of view. For example, referring to Figures 2A and 2B, the bounding box volume of the folded field of view 218 may be 78% of the bounding box volume of the unfolded field of view 219. In Figures 2A and 2B, the volume of the folded field of view 218 and the volume of the unfolded field of view 219 may be different because, although the depth of each bounding box, for example, the dimension along the Z-axis, is the same, the area in the XY plane is different.

[0032] The field of view can be further described by two angles that define, for example, the horizontal range in the XY plane and the depth range along the Z axis. In some implementations, the field of view is 20 × 31 square degrees. Visualizing the field of view of camera 105, as well as how to adjust the relative position and orientation of the mirror 104 and camera 105 with respect to the scintillator 103, can be simplified by not folding the field of view.

[0033] Figure 2B depicts the unfolded Figure 200b of the detection subsystem 200a, which is adjustable to create a configuration that prevents specular triple reflection. Compared to Figure 2A, the field of view on the other side of mirror 104 in Figure 2B is inverted around an axis that coincides with the orientation of mirror 104. Thus, points F and G are on the straight line AFE and AGD in Figure 2B, and points F and G are the locations of the corners of the folded field of view in Figure 2A. The conversion between Figure 2A and Figure 2B is possible because mirror 104 reflects light around an axis perpendicular to the surface of mirror 104.

[0034] Points A, D, and E are the same as points A, D, and E in Figure 2A. Point B is the location of the intersection of the optical axis 209 and mirror 104. Point C is the location of the intersection of the optical axis 209 and scintillator 103. The angle θ is the same angle as in Figure 2A, for example, the angle between plane 208 and mirror 104. Using these points, the following distances are defined: the distance from camera 105 to scintillator 103 is R=|AC|, the distance from mirror to scintillator is M=|BC|, and the size of scintillator 103 is S=|DE|. In some implementations, the size of mirror 104, for example, the distance from point G to point F, is smaller than the size of scintillator S. In some implementations, to account for errors in the mechanical alignment of the X-ray apparatus 100, either the mirror or the scintillator does not perfectly align with the camera's field of view.

[0035] The angle at which triple specular reflection occurs is a function of the distance R from the camera to the scintillator, the distance M from the mirror to the scintillator, and the size S of the scintillator. Using the above definition, the threshold angle θ for determining whether the triple specularly reflected light from scintillator 103 reaches camera 105 is S teeth:

[0036]

number

[0037]

number

[0038]

number

[0039] threshold angle θ S θ is the transition point; if it is higher than θ, specular triple reflection is avoided, and if it is lower than θ, specular triple reflection occurs. Therefore, θ S By configuring the detection subsystem 200a to have the above angle θ, unwanted specular triple reflections can be reduced or eliminated. For example, "specular triple reflection" refers to three reflections that are specular reflections (two at mirror 104 and one at scintillator 103). Therefore, several implementation forms have a threshold angle θ. S The size, position, and orientation of the mirror 104 and camera 105 (relative to the predetermined size, position, and orientation of the scintillator 103) are selected to maintain an angle θ that is greater than (or equal to) θ, and therefore ensure that triple specular reflection does not interfere with 3D reconstruction.

[0040] Figure 2C depicts an unfolded view of the detection subsystem 200c that prevents specular triple reflection. Figure 2C is the same as Figure 2B except that θ’ is greater than θ and θ, which means that specular triple reflection is avoided. In other words, there is no optical path from the scintillator 103 to the camera 105 that involves three specular reflections. S However, triple reflection does not always involve only specular reflection. Figure 3A depicts an example of a detection subsystem 300a that includes a scintillator 103, a mirror 104, and a camera 105 of an X-ray device 100 that is adjustable to create a configuration that allows diffuse triple reflection. Examples of complete optical paths include optical paths 311, 312, 313, and 314. The light emitted from the scintillator 103 follows the optical path 311 towards the mirror 104 and then reflects off the mirror 104 at the specular reflection 315. Then, the light travels along the optical path 312 and undergoes a diffuse reflection 316. As can be seen in Figure 3A, the angle of incidence θ

[0041] is not equal to the angle of reflection θ i at the diffuse reflection 316. Then, the light follows the optical path 313 and then undergoes a specular reflection 317 off the mirror 104. Finally, the light follows the optical path 314, which leads to the camera 105. r Similar to the detection subsystem 200a, the camera 105 can define an optical axis 309, and the mirror can intersect a plane 308 perpendicular to the optical axis 309 at an angle θ. The second angle threshold θ

[0042] for determining whether diffuse triple reflection occurs is: D is:

[0043]

Equation

[0044] The threshold angle θ Dθ is a transition point; if it is higher, diffuse triple reflection is avoided, and if it is lower, diffuse triple reflection occurs, meaning three reflections including two specular reflections at mirror 104 and one diffuse reflection at scintillator 103. For all configurations, θ S ≤θ D Therefore, in order to avoid both specular triple reflection and diffuse triple reflection, the detection subsystem 300a uses θ D It should be configured such that ≤θ. Therefore, some implementations have a threshold angle θ. D The size, position, and orientation of the mirror 104 and camera 105 (relative to the predetermined size, position, and orientation of the scintillator 103) are selected to maintain an angle θ that is greater than (or equal to) θ, and therefore ensure that triple diffuse reflection does not interfere with 3D reconstruction.

[0045] In some implementations, the threshold angle θ DIt is not necessary to maintain an angle θ greater than (or equal to) θ. Diffuse triple reflection is generally less bright than specular triple reflection to camera 105; for example, less light enters camera 105 from diffuse triple reflection than from specular triple reflection. Diffuse triple reflection may be less bright than specular triple reflection for various reasons. For example, the surface of scintillator 103 may be relatively smooth, so it mostly allows specular reflection, but has small roughness areas that allow diffuse reflection. By definition, mirrors allow specular reflection, and therefore mirror 104 generally does not allow diffuse reflection. However, a mirror with defects such as scratches may allow diffuse reflection at the location of the defects. As another example, the geometry of the configuration of scintillator 103, mirror 104, and camera 105 can be such that light following an optical path containing only specular reflection is more likely to enter camera 105 than light due to diffuse reflection with a random angle determining one of the segments of the optical path. Therefore, mitigating the effect of diffuse triple reflection may be less important than mitigating the effect of specular triple reflection. Thus, the size of the folded field of view of the camera (and similarly, the size of the detection subsystem) can be further reduced by enabling triple diffuse reflection while preventing triple specular reflection. Thus, in some implementations, structural constraints on the geometry of the detection subsystem 200a, as depicted in Figure 3A, enable diffuse triple reflection but prevent specular triple reflection:θ S ≤θ<θ D .

[0046] Figure 3B depicts an unfolded diagram of the detection subsystem 300b that prevents both diffuse triple reflection and specular triple reflection. In Figure 3B, θ'' is θ''. S It not only has the requirement that it is greater than θ, but also D It is the same as Figure 2C, except that it also has the requirement of being larger than [a certain value].

[0047] By preventing triple reflection, for example n=3, higher-order reflections, such as n=5 or 7, are further prevented. Generally, in most configurations, the order of reflection is odd because the last reflection occurs only at mirror 104. Typically, higher-order reflections contribute only a small amount to the light received by camera 105.

[0048] In some implementations, the geometry of the detection subsystem is such that the angle θ has some margin to account for structural defects in the X-ray apparatus 100. S or θ D It can be determined such that it is greater than either of the two. For example, the angle θ can be set to θ by 5%. S or θ D It can be made larger than either one of them.

[0049] Those skilled in the art will readily understand that the implementations discussed above may be practiced in different sequences of steps and / or with hardware elements of different configurations than those disclosed. Therefore, while several implementations have been described based on these, it will be apparent to those skilled in the art that certain modifications, variations, and alternative constructs will be obvious, remaining within the spirit and scope of the implementations. [Explanation of Symbols]

[0050] 100 X-ray equipment 101 X-ray source 102 X-rays, X-ray radiation 103 Scintillator 104 Single mirror, mirror 105 Camera 106 Motor Systems 107 Scanning Target 108 Infrared light, ultraviolet light, visible light, light 109 Computers 110 Shroud 111 Enclosure 113 Mount 200a Detection subsystem, detector assembly 200b Unfolded diagram 200c detection subsystem 201 Light path 202 Light path 203 Light path 204 Light path 205 First reflection 206 Second Reflection 207 Third Reflection 208 A plane perpendicular to the optical axis of the camera, a plane 209 Optical axis of the camera, optical axis 218 Folded field of view 219 Unfolded field of view 300a Detection Subsystem 300b Detection subsystem 308 A plane perpendicular to the optical axis 309 Optical axis 311 Light path 312 Light path 313 Light path 314 Light path 315 Specular reflection 316 Diffuse reflection 317 Specular reflection

Claims

1. X-ray device, An X-ray source configured to emit X-rays, A scintillator is configured to absorb X-rays after interaction with an object placed in the X-ray apparatus at a first surface of the scintillator, and to emit light from a second surface of the scintillator in response to the absorption of X-rays, A single mirror is positioned to reflect the light from the second surface of the scintillator toward the camera, The camera is positioned to receive the light reflected from the single mirror. Equipped with, The camera has a field of view centered on the optical axis of the camera, The single mirror is large enough to completely encompass the field of view, so that the field of view is folded back toward the scintillator by the single mirror. The single mirror is positioned at an angle with respect to a plane that is perpendicular to the optical axis at the point where the optical axis intersects the single mirror, The angle is reduced from 45 degrees to reduce the volume of the folded field of view of the camera. X-ray apparatus, wherein the angle is greater than or equal to a threshold angle that prevents triple specular reflection of light between the single mirror and the scintillator, and the threshold angle is set according to (i) a first distance along the optical axis between the camera and the scintillator, (ii) a second distance along the optical axis between the single mirror and the scintillator, and (iii) the size of the scintillator.

2. The X-ray apparatus according to claim 1, wherein the angle of the single mirror with respect to the plane is smaller than a further threshold angle that prevents a combination of double specular reflection of light at the single mirror and single diffuse reflection of light at the scintillator.

3. The X-ray apparatus according to claim 1, wherein the angle of the single mirror with respect to the plane is greater than a further threshold angle that prevents a combination of double specular reflection of light at the single mirror and single diffuse reflection of light at the scintillator.

4. The X-ray apparatus according to claim 1, wherein the bounding box volume of the folded field of view of the camera is 78% of the bounding box volume of the unfolded field of view of the camera.

5. The X-ray apparatus according to claim 1, wherein the field of view of the camera is 20 × 31 square degrees.

6. The X-ray apparatus according to claim 1, further comprising a shroud positioned to prevent stray light from adversely affecting the camera.

7. The X-ray apparatus according to claim 6, wherein the shroud is positioned between the X-ray source and the camera.

8. The X-ray apparatus according to claim 1, further comprising a motion system for moving the camera, the subject, or both during scanning.

9. The X-ray apparatus according to claim 1, A computer programmed to execute an algorithm for performing a three-dimensional reconstruction of the subject using data generated by the light received by the camera. A system that includes these features.

Images