Hybrid X-ray and optical detectors

Abstract

The present invention relates to an imaging detector. In order to provide a hybrid X-ray and optical detector with enhanced optical imaging capabilities and a simple design, an imaging detector is provided for capturing optical imaging data and X-ray imaging data. The imaging detector includes an array of a substrate, a photosensitive sensor, an X-ray scintillator and an optical component device. The photosensitive sensor includes sensor pixels distributed on the imaging detector. The X-ray scintillator is configured to convert the energy of incident X-ray radiation into photons. Each optical component device includes at least one optical component configured to guide the incident optical radiation toward the photosensitive sensor. The sensor pixels include optical pixels, each coupled to a corresponding optical component device to receive the incident optical radiation, thereby generating the optical imaging data. The sensor pixels include X-ray pixels, which are coupled to the X-ray scintillator to receive the converted photons, thereby generating the X-ray imaging data.

Description

Technical Field

[0001] The present invention relates to an imaging detector, and in particular to an imaging detector for capturing optical imaging data and X-ray imaging data, an imaging system and a method for manufacturing the imaging detector. Background Art

[0002] Integrating optical imaging in an X-ray imaging system can provide valuable functional information in a variety of medical and non-medical applications. In medical applications, for example, such dual imaging systems are mainly built into a gantry, where separate optical and X-ray image acquisition channels are mechanically combined and the acquired images are co-registered and fused together. Since the X-ray and optical images are not acquired at the same time and place, this imaging concept often leads to imaging inaccuracies and imaging artifacts caused by differences in acquisition time and patient movement. This problem can be solved by hybrid X-ray and optical detectors.

[0003] Current hybrid X-ray and optical detectors may have limited optical functionality and complex interconnections between the many optical sensor segments.

[0004] For example, WO 2016 / 131647 A1 describes a hybrid X-ray and optical detector built from an X-ray detector by interleaving a number of optical sensor segments in a common imaging area.

[0005] US 2007 / 238957 A1 describes a combined X-ray and optical (light-based) tomographic imaging system that provides functional information at a greater resolution than can be achieved by optical tomography alone.

[0006] EP 1715361 A1 describes a dual-modality imaging system, wherein a positron emission tomography (PET) scanner for acquiring PET imaging data and at least one optical imaging detector for acquiring optical imaging data are arranged to simultaneously acquire PET imaging data and optical imaging data of an imaged object. Summary of the invention

[0007] It may be desirable to provide a hybrid X-ray and optical detector having enhanced optical imaging capabilities and a simple design.

[0008] The objects of the invention are solved by the subject-matter of the independent claims, wherein further embodiments are included in the dependent claims.It should be noted that the following described aspects of the invention also apply to an imaging detector, an imaging system and a method for manufacturing an imaging detector.

[0009] A first aspect of the present invention relates to an imaging detector for capturing optical imaging data and X-ray imaging data. The imaging detector comprises a substrate, a photosensitive sensor, an X-ray scintillator and an array of optical component devices. The photosensitive sensor comprises sensor pixels distributed on the imaging detector. The X-ray scintillator is configured to convert the energy of incident X-ray radiation into photons. Each optical component device comprises at least one optical component configured to direct incident optical radiation toward the photosensitive sensor. The sensor pixels comprise optical pixels, each coupled to a corresponding optical component device to receive the incident optical radiation, thereby generating optical imaging data. The sensor pixels comprise X-ray pixels, which are coupled to the X-ray scintillator to receive the converted photons, thereby generating the X-ray imaging data.

[0010] In other words, a common photosensitive sensor can be used, on which either pixelated or continuous X-ray scintillators and optical components are arranged. The distribution and properties of "X-ray pixels" and "optical pixels" across the detector area can be flexibly selected and optimized for specific hybrid imaging applications, as will be explained in more detail below. Manufacturing concepts derived from the rapidly emerging "microLED" display technology can be used to manufacture imaging detectors.

[0011] The term "array" may be understood as a one-dimensional array or a two-dimensional array.

[0012] The X-ray scintillator may be a pixelated scintillator or a continuous scintillator (or a non-pixelated scintillator).

[0013] The optical component arrangement may include one or more optical components configured to direct incident optical radiation 26 toward the light-sensitive sensor. The optical components may include, for example, microlenses, spectral filters, one-way or semi-transparent mirrors, light guides, polarizers, diffraction gratings, gradient index lenses, holographic components, optical collimators such as elongated tubes or cuboids, and microprisms. In addition to switchable elements such as liquid crystal lenses, water- and oil-based liquid crystal lenses or semi-transmissive and semi-reflective liquid crystal mirrors may also be used as optical components.

[0014] The photosensitive sensor can be configured for the expected hybrid imaging application. Typical examples of sensors are: CMOS image sensors on wafer-level silicon substrates, amorphous Si TFT and backplane arrays of photodiode pixels on glass substrates or on polyimide foil substrates, and backplane arrays of organic TFT and photodiode pixels on polyimide foil substrates. Large FOV sensors can be realized by tiling multiple smaller sensors (e.g., CMOS) together. The design of the X-ray pixel and the optical pixel (and its photodiode) should match the properties of the X-ray scintillator and the optical components, respectively.

[0015] The optical pixel may comprise one or more photodiodes (not shown), each coupled to one or more (stacked) optical components, such as microlenses, light guides, optical filters. At least two optical pixels may be assigned to one sensor pixel, each optical pixel thus forming a sub-pixel of the sensor pixel. Alternatively, at least two sensor pixels are assigned to one optical pixel, each sensor pixel thus forming a sub-pixel of the optical pixel. This may be advantageous for dynamic discrimination or resolution requirements for optical imaging.

[0016] The X-ray pixel may comprise one or more photodiodes, each photodiode being coupled to one or more (stacked) X-ray scintillator elements. At least two X-ray pixels may be assigned to one sensor pixel, each X-ray pixel thus forming a sub-pixel of the sensor pixel. Alternatively, at least two sensor pixels are assigned to one X-ray pixel, each sensor pixel thus forming a sub-pixel of the X-ray pixel. This may be advantageous for dynamic discrimination or resolution requirements for X-ray imaging.

[0017] X-ray pixels and optical pixels can be designed of any desired size and shape. Moreover, pixels can be grouped to form "X-ray sensor segments" or "optical sensor segments" in the detector field of view. In this way, any optimal distribution of X-ray pixels and optical pixels across a common sensor array can be arranged for a particular imaging application. Examples are: staggered individual pixels, staggered sensor segments, alternating lines of pixels, alternating sensor segment stripes, concentric circles (or rectangles) of sensor segments, checkerboards of sensor segments, and surrounding sensor segments.

[0018] According to an embodiment of the invention, at least one optical component arrangement comprises a light converging component for focusing or narrowing incident optical radiation onto said light sensitive sensor. Said light converging component is at least one selected from a microlens and an optical collimator.

[0019] The term "optical collimator" as used herein may be described as an optical component that focuses or narrows a light beam to align or reduce its cross-section in different directions. For example, the optical collimator may be a slightly elongated tube or cuboid above an optical pixel that limits the acceptance angle of the optical pixel.

[0020] The use of light focusing components (such as microlenses or optical collimators), optionally in combination with light guides, optical filters and / or light sources, advantageously enables the realization of desired optical imaging capabilities. Examples are: large field of view viewing, autostereoscopic imaging, three-dimensional light field imaging, time-of-flight imaging, three-dimensional light detection and ranging (LIDAR) imaging, hyperspectral imaging, and optical tomography.

[0021] According to an embodiment of the invention, the X-ray scintillator is a pixelated scintillator comprising an array of scintillator elements. The array of the optical component device and the array of the scintillator elements are positioned relative to each other for directing the incident optical radiation to the sensor pixels within the gaps between the scintillator elements, thereby forming separate optical and X-ray pixels. Alternatively, the array of the optical component device and the array of the scintillator elements are positioned relative to each other for directing the incident optical radiation to the sensor pixels coupled to the X-ray scintillator, thereby forming common optical and X-ray pixels.

[0022] Thus, the present invention may provide the option of designing separate sensor pixels for optical and X-ray images and thus deliver both images simultaneously without special requirements for illumination or shutter movement or image correction to eliminate crosstalk between the optical and X-ray images.

[0023] The present invention may provide an alternative option of designing common or shared sensor pixels for optical and X-ray images. This option may be suitable for optimizing the properties of a hybrid detector for time-interleaved X-ray and optical imaging. An optical switch, such as a liquid crystal module, may be suitable for switching its optical properties synchronously with time-interleaved X-ray and optical imaging.

[0024] According to an embodiment of the invention, at least one component arrangement comprises a light guide arranged inside the gaps between the scintillator elements. The light guide is coupled with respective light converging components to direct the incident optical radiation towards the sensor pixels within the gaps between the scintillator elements.

[0025] According to an embodiment of the present invention, the light converging component is a microlens. The microlens has at least one of the following shapes and positions:

[0026] i) symmetrically shaped microlenses in symmetrical positions with respect to the corresponding light guides,

[0027] ii) symmetrically shaped microlenses in asymmetrical positions relative to the corresponding light guides, and

[0028] iii) Asymmetric shape microlenses. This will Figures 2A to 2C The embodiments are explained in more detail in the text.

[0029] According to an embodiment of the present invention, the microlens is a composite microlens. The position of the composite microlens is at least one of the following:

[0030] i) inside the gaps between scintillator elements,

[0031] ii) inside the gaps between trapezoidal scintillator elements, and

[0032] iii) Above the gaps between the trapezoidal scintillator elements. This will Figures 3A to 3C The embodiments are explained in more detail in the text.

[0033] According to an embodiment of the present invention, the array of optical component devices and the array of scintillator elements are arranged on opposite sides of the photosensitive sensor. The photosensitive sensor is photosensitive on both sides. Each optical component device is configured to guide the incident optical radiation toward one or more X-ray pixels coupled to the corresponding scintillator element. Alternatively, the array of optical component devices and the array of scintillator elements are arranged on the same side of the photosensitive sensor. Each optical component device is configured to guide the incident optical radiation passing through the corresponding scintillator element toward one or more X-ray pixels. Alternatively, at least one scintillator element has a surface shape configured in such a way that at least one scintillator element itself acts as a microlens for optical imaging.

[0034] According to an embodiment of the present invention, the array of scintillator elements comprises scintillator elements having the following:

[0035] i) Different thickness,

[0036] ii) different sizes between scintillator elements,

[0037] iii) a size that is different compared to the size of the sensor pixel,

[0038] iv) different distance gaps, v) non-uniform distribution,

[0039] vi) different radiation conversion materials, and / or

[0040] vii) Different compositions of radiation conversion materials. The compositions of the radiation conversion materials differ in at least one of the following:

[0041] The doping levels of the radiation conversion materials, the doping materials and the combinations of doping materials.

[0042] In an example, a central region of the imaging detector may have a thicker scintillator element, while a non-central (eg, peripheral) region of the imaging detector may have a thinner scintillator element.

[0043] In an example, the size of the scintillator elements may increase from the center toward the periphery, resulting in high spatial resolution at the center and low resolution at the periphery while saving material costs for the electronics.

[0044] In an example, at least two scintillator elements are assigned to one sensor pixel. Each scintillator element is coupled to a photodiode and forms an X-ray sub-pixel of one sensor pixel. The composition of the radiation material and / or the thickness of the radiation material can vary between at least two X-ray sub-pixels assigned to one sensor pixel. This can be used in applications such as high contrast images of medical tissue of objects with very large differences in material X-ray absorption properties.

[0045] In an example, at least two sensor pixels are assigned to one scintillator element. In other words, the scintillator element has a size that is larger than the size of the sensor pixels.

[0046] In an example, a central region of the imaging detector may have a high-quality, expensive radiation conversion material, such as CsI, while a non-central (eg, peripheral) region of the imaging detector may have a low-quality, inexpensive radiation conversion material, such as GOS.

[0047] In an example, the non-uniform distribution of the array of scintillator elements is a non-uniform distribution of the composition and / or thickness of the radiation conversion material of the scintillator elements.

[0048] In an example, the non-uniform distribution of the array of scintillator elements can be provided by a non-uniform distribution at the pixel binning level, such as 1x1, 2x2, 3x3 to 4x4 binning from a central area towards the periphery of the detector, or generally nxm binning with increasing n, m.

[0049] In an example, a central region of the imaging detector may have a smaller distance gap, while a non-central (e.g., peripheral) region of the detector may have a larger distance gap, resulting in high spatial resolution in the center and low resolution in the periphery while saving material costs for electronics.

[0050] According to an embodiment of the invention, the X-ray scintillator is a continuous scintillator comprising a radiation conversion material.

[0051] According to an embodiment of the present invention, at least one microlens is configured as an optical filter for selectively transmitting light having different wavelengths.

[0052] In other words, the microlens itself can also act as an optical filter. For example, a composite microlens includes an embedded optical filter. This can be useful in fluorescent image-guided surgery for real-time visualization of tissues colored by fluorescent dyes, such as FDA-approved indocyanine green (ICG). The surgeon can then work in normal room light conditions, while the narrow bandwidth spectral filter in the microlens mainly blocks the room light and mainly transmits the light emitted by the dye. In the same way, the light guide can also act as an optical filter.

[0053] According to an embodiment of the present invention, a semi-transmissive and semi-reflective optical mirror is provided. The semi-transmissive and semi-reflective optical mirror is provided as an array of filters, each filter being configured to block one or more X-ray pixels from receiving the incident optical radiation. Alternatively or additionally, the semi-transmissive and semi-reflective optical mirror is provided as an array of optical switches, each optical switch being configured to enable the incident optical radiation received by one or more X-ray pixels to be selectively switched on and off synchronously with time-interleaved X-ray and optical imaging.

[0054] In an example, the transflective optical mirror is a transflective optical coating.

[0055] The use of a semi-transmissive and semi-reflective optical mirror as an optical switch can advantageously solve problems associated with conventional optical shutters, such as correction of light-only images to retrieve X-ray images, turning off lights (including room lights) when acquiring X-ray images, or closing a (large) optical shutter.

[0056] This can advantageously enable real-time medical (eg, in a surgical operating room (OR) / hybrid or interventional room) and real-time non-medical imaging applications.

[0057] According to an embodiment of the invention, the array of optical component means comprises microlenses having:

[0058] i) Different focal lengths,

[0059] ii) Different distance gaps;

[0060] iii) non-uniform distribution;

[0061] iv) different sizes between microlenses, and / or

[0062] v) A size that is different compared to the size of the sensor pixels.

[0063] The non-uniform distribution of the array of microlenses may be a non-distribution of the focal length or size of the microlenses.

[0064] In an example, the non-uniform distribution of microlenses may be provided by a non-uniform distribution at the pixel binning level, such as from 1x1, 2x2, 3x3 or 4x4 pixel bins from a central area towards the periphery of the detector.

[0065] In an example, at least two microlenses are assigned to one sensor pixel, each forming an optical sub-pixel. The focal length and / or size may vary between the at least two optical sub-pixels assigned to one sensor pixel.

[0066] In another example, at least two sensor pixels are assigned to one microlens.

[0067] In an example, the microlenses have an increasing size from the center toward the edge.

[0068] In an example, the microlenses have an increasing distance gap from the center toward the edge.

[0069] According to an embodiment of the invention, the substrate comprises a flat or substantially flat or curved shape.The substrate comprises silicon, glass or a polymer foil.

[0070] The term "substantially flat" may be understood to include flatness up to a minimum bending radius of 1 cm.

[0071] A second aspect of the present invention relates to an imaging system. The imaging system comprises an imaging detector, an X-ray source and a light source according to any of the embodiments described above and below. The X-ray source is configured to provide X-ray radiation. The light source is configured to provide optical radiation. The imaging detector is configured to detect X-ray radiation to generate X-ray imaging data, and detect optical radiation to generate optical imaging data.

[0072] A third aspect of the present invention relates to a method for manufacturing an imaging detector. The method comprises the following steps: a) forming a substrate, b) forming a photosensitive sensor on the substrate, and c) arranging an array of X-ray scintillators and / or optical component devices on the photosensitive sensor and / or on the substrate layer by a pick-and-place assembly transfer process, and wherein the photosensitive sensor comprises sensor pixels distributed on the imaging detector. The X-ray scintillator is configured to convert the energy of incident X-ray radiation into photons. Each optical component device comprises at least one optical component configured to direct incident optical radiation toward the photosensitive sensor. The sensor pixels comprise optical pixels, each coupled to a corresponding optical component device to receive the incident optical radiation, thereby generating the optical imaging data. The sensor pixels comprise X-ray pixels, which are coupled to the X-ray scintillator to receive the converted photons, thereby generating the X-ray imaging data.

[0073] The detector assembly process can start with the separate fabrication of pixelated "donor arrays", i.e., processing of bulk scintillator substrates into arrays of scintillator tiles, and fabrication and cutting of optical microstructures on the substrates into arrays of optical imaging components (e.g., microlenses on wafers, optical filters on foils). These donor arrays are then balanced for picking up and delivering individual tiles to "acceptor arrays". This is the common photosensitive sensor where heterogeneous integration of all X-ray and optical imaging components into a hybrid detector occurs.

[0074] According to aspects of the present invention, an imaging detector for capturing X-ray imaging data and optical imaging data is provided. The imaging detector is characterized by a common photosensitive sensor including a plurality of photosensitive pixels and electronic circuitry for the purpose of capturing and processing images resulting from exposure to X-ray radiation and / or optical radiation. The optical radiation may be ultraviolet (UV), visible light (VIS), infrared light (IR), or near infrared light (NIR). This may eliminate interconnection issues for optical sensor components. It may also provide enhanced optical imaging capabilities, and it may reduce the cost price of the detector. The implementation of this simpler, more flexible and cheaper hybrid detector design may be enabled by the rapidly emerging manufacturing component concepts for MicroLED displays.

[0075] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] A more complete understanding of the invention and its attendant advantages will be more clearly appreciated from the following schematic diagrams, which are not drawn to scale, wherein:

[0077] Figure 1 A schematic diagram of an imaging detector according to an embodiment of the present invention is shown.

[0078] Figures 2A to 2D A schematic diagram of an imaging detector according to an embodiment of the present invention is shown.

[0079] Figures 3A to 3C A schematic diagram of an imaging detector according to other embodiments of the present invention is shown.

[0080] Figure 4 A schematic diagram of an imaging detector according to another embodiment of the present invention is shown.

[0081] Figures 5A to 5C A schematic diagram of an imaging detector according to other embodiments of the present invention is shown.

[0082] Fig. 6A and 6B A schematic diagram of an imaging detector according to another embodiment of the present invention is shown.

[0083] Fig. 7A and 7B A schematic diagram of an imaging detector according to other embodiments of the present invention is shown.

[0084] Figure 8 A schematic diagram of an imaging system according to an embodiment of the present invention is shown.

[0085] Fig. 9 A schematic diagram of a method for manufacturing an imaging detector according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0086] The illustrations in the drawings are schematic and not to scale.In different drawings, similar or identical elements are provided with the same reference signs.

[0087] Generally, the same components, units, entities or steps are provided with the same reference numerals in the drawings.

[0088] In the figures, each embodiment schematically shows six X-ray pixels and three to six optical pixels, but these pixels need not be adjacent. They can be distributed in any desired configuration across the imaging detector.

[0089] Figure 1 A schematic diagram of an imaging detector 10 according to an embodiment of the present invention is shown. The imaging detector 10 includes a substrate 12, a photosensitive sensor 14, an X-ray scintillator 16, and an array of optical component arrangements 18. The photosensitive sensor 14 includes sensor pixels 20 distributed on the imaging detector 10. The X-ray scintillator 16 is configured to convert energy of incident X-ray radiation 22 into photons. Each optical component arrangement 18 includes at least one optical component 24 configured to direct incident optical radiation 26 toward the photosensitive sensor 14. The sensor pixel 20 includes an optical pixel 28, each coupled to a corresponding optical component arrangement 18 to receive the incident optical radiation 26, thereby generating optical imaging data. The sensor pixel 20 includes an X-ray pixel 30, which is coupled to the X-ray scintillator 16 to receive the converted photons, thereby generating X-ray imaging data.

[0090] In an example, substrate 12 comprises a flat or substantially flat shape. In another example, substrate 12 comprises a curved shape. Curved detectors can be useful in various situations, for example, compact X-ray, computed tomography (CT) or cone beam computed tomography (CBCT) imaging systems or designs for imaging curved body parts. Examples are chest imaging or flexible detector blankets that (partially) cover and / or contact a patient. Curved detectors can also be useful for inspection (NDT) of industrial pipelines (gas, oil, water). Substrate 12 can include silicon, glass or polymer foil. Substrates with polymer foil can be enabled, for example, by sensor-on-foil technology.

[0091] The X-ray scintillator 16 can be a pixelated scintillator or a continuous scintillator. Figure 1 5 and 7A, the X-ray scintillator 16 is a pixelated scintillator. In an example, as shown in FIGS. 6 and 7B, the X-ray scintillator 16 is a continuous scintillator.

[0092] In the example, at least one optical component arrangement includes a light converging component 31 (shown in FIGS. 2 to 7 ) for focusing or narrowing the incident optical radiation 26 onto the photosensitive sensor 14. The light converging component 31 is at least one selected from a microlens 32 and an optical collimator (not shown). For simplicity, the light converging component 31 in FIGS. 2 to 7 is illustrated and shown as a microlens 32. It will be appreciated that in some embodiments, the light converging element 31 may be an optical collimator, such as a slightly elongated tube or a cuboid. For example, instead of or in addition to the microlens 32 in FIGS. 2 to 7 , an optical collimator may also be applied.

[0093] In the example, Figures 1 to 4 and Fig. 7A As shown, the X-ray scintillator 16 is a pixelated scintillator that includes an array of scintillator elements 34. The array of optics 18 and the array of scintillator elements 34 are positioned relative to each other to direct incident optical radiation 26 to the sensor pixels 20 within gaps 36 between the scintillator elements 34, thereby forming separate optical and X-ray pixels.

[0094] In an example, as an alternative concept, the array of optics arrangement 18 and the array of scintillator elements 34 are positioned relative to each other to direct incident optical radiation 26 to sensor pixels 20 coupled to the X-ray scintillators 16, thereby forming common optical and X-ray pixels. FIG. 5A to FIG. 5C This concept is shown in .

[0095] Figures 2A to 2D FIG. 1 is a schematic diagram of an imaging detector 10 according to an embodiment of the present invention. Figures 2A to 2D, at least one component arrangement 18 comprises a light guide 38 arranged inside the gaps 36 between the scintillator elements 34. The light guide 38 is coupled with a corresponding light converging component 31 for guiding incident optical radiation 26 towards the sensor pixels 20 within the gaps 36 between the scintillator elements 34. For simplicity, the incident optical radiation 26 and the incident X-ray radiation 22 are illustrated as one arrow. The light converging component 31 may be a microlens 32.

[0096] In the example, Figure 2A As shown, the microlenses 32 are symmetrically shaped microlenses in symmetrical positions relative to the corresponding light guides 38 .

[0097] In the example, Figure 2B As shown, microlenses 32 are symmetrically shaped microlenses in asymmetrical positions relative to respective light guides 38. In this example, the position of the symmetrical microlenses relative to the light guides and underlying photodiodes can be optimized for each position on the sensor area to ensure the maximum set of incident light for each viewing angle.

[0098] In the example, Figure 2C As shown, the microlens 32 is an asymmetrically shaped microlens. In this example, the shape of the asymmetrical microlens relative to the light guide and underlying photodiode can be optimized for each location on the sensor area to ensure the maximum collection of incident light for each viewing angle.

[0099] Optionally, optical filters and / or light sources may be provided to advantageously enable implementation of desired optical imaging capabilities.

[0100] In the example, Figure 2D As shown, a filter 40 is provided. The application of different filters in adjacent optical pixels can advantageously enable hyperspectral imaging of tissue. The visibility of tumor tissue in oncology surgical procedures can be enhanced by using different contrasts of optical images in specific wavelength bands. The filter 40 can be applied at different locations. The filter 40 can also be applied in a layer, below or above the microlens 32 or light guide 38.

[0101] Optionally, at least one microlens 32 is configured as an optical filter for selectively transmitting light having different wavelengths. In other words, the microlens itself can also act as an optical filter. For example, Figures 3A to 3C The composite microlenses in may include embedded optical filters. Optionally, the light guide 38 is configured as an optical filter for selectively transmitting light having different wavelengths.

[0102] In the example, Figure 2DAs shown, a light source 42 is provided in the periphery of the X-ray scintillator 16 and / or in the gap 36. The application of a small light source at the periphery of the X-ray scintillator and / or inside the gap (such as a microLED or a vertical cavity surface emitting laser (VCSEL)) can advantageously enable the three-dimensional or multi-spectral imaging capability of the hybrid detector. For example, the light source can be configured to emit light pulses at different wavelengths synchronized with the pulsed X-ray exposure of the patient to enable time-interleaved hybrid imaging. This means that continuous light images and X-ray images are collected quickly after each other. The light source can be used to add advanced three-dimensional sensing functions (such as anti-collision systems) to the detector by using time of flight (ToF) or LIDAR technology. From consumer electronics devices (e.g., Kinect motion sensing, IphoneX three-dimensional light camera, ToF proximity sensor, etc.) can also be used in the hybrid detector. The light source can be used to implement dedicated lighting functions independently of imaging or sensing. A useful example for surgeons in an operating room (OR) environment can be the generation of shadow-free lighting and the projection of relevant information on the patient (e.g., the entry point for the insertion of a surgical needle).

[0103] The combination of multiple light sources, optionally combined with optics to focus the light onto a large surface (the detector), enables a surgical light with excellent shadow dilution properties. This enables the use of the detector in surgical settings such as a hybrid OR during surgical procedures.

[0104] Figures 3A to 3C FIG. 1 is a schematic diagram of an imaging detector 10 according to another embodiment of the present invention. Figures 3A to 3C In FIG. 3 , the microlens 32 is a composite microlens including a collection of lenses. In view of the X-ray scintillator thickness ranging from 100 μm to 1000 μm, the composite microlens may be useful in preventing light loss due to reflection / absorption phenomena in the gap between adjacent scintillator elements.

[0105] In the example, Figure 3A As shown, the composite microlenses are positioned within the gaps 36 between the scintillator elements 34 .

[0106] In the example, Figure 3B As shown, the location of the composite microlens is within the gaps 36 between the trapezoidal scintillator elements 34. This can advantageously enable Figure 3A The microlenses need to have a symmetrical shape and be tilted towards the border of the sensor to optimally correct the oblique incidence of the light beam.

[0107] In the example, Figure 3C As shown, the composite microlens is positioned above the gaps 36 between the trapezoidal scintillator elements 34. This can advantageously enable an increase in X-ray sensitivity while still maintaining the same Figure 3A Reasonable viewing angle and optical sensitivity compared to the examples in . This can be achieved by using an enhanced design of microlenses above the scintillator layer (e.g., in a hexagonal pixel structure).

[0108] Figure 4 FIG. 1 is a schematic diagram of an imaging detector 10 according to another embodiment of the present invention. Figure 4 In the example, the array of optical components 18 and the array of scintillator elements 34 are arranged on opposite sides of the photosensitive sensor 14. The photosensitive sensor 14 is photosensitive on both sides. The array of optical components 18 and the array of scintillator elements 34 are positioned relative to each other for directing incident optical radiation 26 to the optical pixels 28 within the gaps 36 between the scintillator elements 34. In this example, the sensor has dedicated sensor pixels for X-ray imaging and optical imaging, i.e., separate X-ray pixels 30 and optical pixels 28. This embodiment can advantageously increase the flexibility in the selection of optical components and facilitate the manufacturing assembly process.

[0109] Figures 5A to 5C FIG. 2 shows a schematic diagram of an imaging detector 10 according to another embodiment of the present invention.

[0110] In the example, Figure 5A As shown, an array of optical component arrangements 18 and an array of scintillator elements 34 are arranged on opposite sides of the photosensitive sensor 14. The photosensitive sensor 14 is photosensitive on both sides. Each optical component arrangement 18 is configured to direct incident optical radiation 26 toward one or more sensor pixels 20 coupled to a corresponding scintillator element 34. This may be suitable for optimizing the properties of a hybrid detector for time-interleaved X-ray and optical imaging.

[0111] In the example, Figure 5B As shown, the array of optical component arrangements 18 and the array of scintillator elements 34 are arranged on the same side of the photosensitive sensor. Each optical component arrangement 18 is configured to direct incident optical radiation 26 that passes through the corresponding scintillator element 34 toward one or more sensor pixels 20. This may be suitable for optimizing the properties of a hybrid detector for time-interleaved X-ray and optical imaging.

[0112] In the example, Figure 5C As shown, at least one scintillator element 34 has a surface shape configured in such a way that at least one scintillator element 34 itself acts as a microlens for optical imaging. The adjusted scintillator surface shape may have a small effect on the X-ray absorption differences of the pixels. These will be taken into account by the standard gain correction of the X-ray image.

[0113] In an example (not shown), Figure 1The array of scintillator elements 34 of the embodiments of 5 to 5 includes scintillator elements 34 having the following: i) different thicknesses, ii) different sizes between scintillator elements, iii) different sizes compared to the size of sensor pixels, iv) different distance gaps, v) non-uniform distribution, vi) different radiation conversion materials, and / or vii) different compositions of radiation conversion materials. The composition of the radiation conversion materials is different in at least one of the following: the doping level of the radiation conversion material, the doping material, and the combination of doping materials. This can advantageously enable dynamic discrimination or resolution for X-ray or CT detectors.

[0114] For example, imaging detectors with a large variation of different dedicated scintillator materials across a continuous scintillator can be used in applications such as tissue differentiation, material detection and separation, and measurement of X-ray tube properties (e.g., X-ray spot size or X-ray spectrum) of X-ray tubes of CT imaging systems.

[0115] For example, imaging detectors having a combination of small and large X-ray scintillator elements within one sensor pixel may be used in applications such as high contrast images of medical tissue or objects having very large differences in material X-ray absorption properties.

[0116] Fig. 6 shows a schematic diagram of an imaging detector 10 with a continuous scintillator according to another embodiment of the present invention. The continuous scintillator includes a radiation conversion material.

[0117] In the example, Fig. 6A and 6B As shown, a semi-transmissive and semi-reflective optical mirror 44 is provided.

[0118] In the example, Fig. 6A As shown, the semi-transmissive and semi-reflective optical mirror 44 is provided as an array of filters 46a. Each filter 46a is configured to block one or more X-ray pixels from receiving incident optical radiation 26. Therefore, these X-ray pixels can only receive X-rays and are dedicated to generating X-ray imaging data.

[0119] In another example, if Figure 6B As shown, the semi-transmissive and semi-reflective optical mirror 44 is provided as an array of optical switches (46b). The optical switch 46b can be arranged between the microlens and the X-ray scintillator or integrated into a microlens module. In an example, as Figure 6BAs shown, the optical switch 46b can be arranged under all microlenses 32. This can be beneficial for practical use for collecting only X-ray images and optical images under room light conditions. In another example (not shown), the optical switch 46b can be arranged under part of the microlens. Each optical switch 46b is configured to enable the incident optical radiation received by one or more X-ray pixels to be selectively turned on and off with the time-interleaved X-ray and optical imaging. For example, the semi-transparent and semi-reflective optical reflector 44 can be a liquid crystal module, a semi-transparent and semi-reflective liquid crystal reflector, or a liquid crystal lens. The semi-transparent and semi-reflective optical reflector 44 can also take the form of a semi-transparent and semi-reflective optical coating. This can advantageously enable real-time imaging applications (e.g., medical imaging applications in surgery, OR / hybrid or interventional rooms). When collecting X-ray images, there is no need to turn off lights (including room lights) or close optical shutters.

[0120] The semi-transparent and semi-reflective optical reflector 44 can also be applied to Figures 5A to 5C The embodiments in .

[0121] In an example, an array of optical component devices includes microlenses having: i) different focal lengths, ii) different distance gaps, iii) non-uniform distribution, iv) different sizes between microlenses, and / or v) different sizes compared to the size of a sensor pixel. This can advantageously create dynamic differentiation or resolution for optical imaging.

[0122] Fig. 7A and 7B FIG. 2 shows a schematic diagram of an imaging detector 10 according to another embodiment of the present invention.

[0123] In the example, Fig. 7A As shown, the microlenses have different focal lengths to optimize optical imaging performance. An array of microlenses with different focal lengths can advantageously enable the imaging detector to remain focused on a range of focal lengths. Thus, the imaging detector has a range of focal lengths ranging from a minimum focal distance to an infinite focal distance, for example. This can be advantageously used in applications requiring inspection of an entire room.

[0124] In the example, Figure 7B As shown, the microlenses have a size that is larger than the size of the sensor pixels.

[0125] In an example (not shown), the size of the microlenses increases from the center towards the periphery, resulting in high spatial resolution in the center and low resolution in the periphery.

[0126] Figure 8A schematic diagram of an imaging system 100 according to an embodiment of the present invention is shown. The imaging system 100 includes an imaging detector 10 of one of the embodiments described above, an X-ray source 48, and a light source 50. The X-ray source 48 is configured to provide X-ray radiation. The light source is configured to provide optical radiation. The imaging detector 10 is configured to detect X-ray radiation to generate X-ray imaging data, and detect optical radiation to generate optical imaging data.

[0127] In the example, Figure 8 As shown, the imaging system 100 is a medical imaging system. A patient support 52 may be provided to carry a patient for medical imaging. Additional medical applications of the imaging system 100 may include: motion compensation, patient positioning, fluorescence image-guided surgery, hyperspectral imaging in surgical oncology, instrument tracking, etc. The imaging system 100 may also be used for non-medical applications, such as non-destructive testing (NDT), food inspection, and safety control.

[0128] Fig. 9 A schematic diagram of a method 200 for manufacturing an imaging detector according to an embodiment of the present invention is shown. The method comprises the following steps: In a first step 210, a substrate is formed. In a second step 212, a photosensitive sensor on the substrate. In a third step 213, an array of X-ray scintillators and / or optical component devices are arranged on the photosensitive sensor and / or on the substrate layer by a pick and place assembly transfer process.

[0129] It must be noted that embodiments of the present invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims, while other embodiments are described with reference to device type claims. However, those skilled in the art will understand from the above and following descriptions that, unless otherwise notified, any combination of features belonging to one type of subject matter, in addition to any combination of features, any combination of features related to different subject matters is also considered to be disclosed by the present application. However, all features may be provided to provide a synergistic effect that exceeds the simple sum of the features.

[0130] Although the present invention has been illustrated and described in detail in the drawings and the foregoing description, such illustration and description are to be considered illustrative or exemplary rather than restrictive. The present invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments may be understood and effected by those skilled in the art in practicing the claimed invention by studying the drawings, the specification, and the appended claims.

[0131] In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. An imaging detector (10) for capturing optical imaging data and X-ray imaging data, comprising: -Substrate(12); - a light-sensitive sensor (14); - X-ray scintillator (16); as well as - an array of optical component devices (18); Wherein, the photosensitive sensor comprises sensor pixels (20) distributed on the imaging detector; wherein the X-ray scintillator is configured to convert energy of incident X-ray radiation (22) into photons; wherein each optical component arrangement comprises at least one optical component (24) configured to direct incident optical radiation (26) towards the light-sensitive sensor; wherein the sensor pixels include optical pixels (28), each optical pixel being coupled to a corresponding optical component device to receive the incident optical radiation to generate the optical imaging data; and The sensor pixels include X-ray pixels (30), which are coupled to the X-ray scintillator to receive converted photons, thereby generating the X-ray imaging data.

2. The imaging detector according to claim 1, in, at least one optical component arrangement comprises a light converging component (31) for focusing or narrowing the incident optical radiation onto the light sensitive sensor; and Wherein, the light converging component is at least one selected from a microlens (32) and an optical collimator.

3. The imaging detector according to claim 1, in, The X-ray scintillator is a pixelated scintillator comprising an array of scintillator elements (34); and wherein the array of optical component devices and the array of scintillator elements are positioned relative to each other for: i) directed to the sensor pixels within the gaps (36) between the scintillator elements, thereby forming separate optical and x-ray pixels; or ii) directed to the sensor pixel coupled to the X-ray scintillator, thereby forming a common optical pixel and X-ray pixel.

4. The imaging detector according to claim 3, in, at least one component arrangement comprises a light guide (38) arranged inside the gaps between the scintillator elements, the light guide optionally being combined with a filter (40) and / or a light source (42); and Wherein the light guide is coupled with a respective light converging component to direct the incident optical radiation towards the sensor pixels within the gaps between the scintillator elements.

5. The imaging detector according to claim 4, in, The light converging member is a microlens; and Wherein, the microlens has at least one of the following shapes and positions: i) symmetrically shaped microlenses in symmetrical positions relative to the corresponding light guides; ii) symmetrically shaped microlenses in asymmetrical positions relative to the corresponding light guides; and iii) Asymmetric shape microlenses.

6. The imaging detector according to claim 2, in, The microlens is a composite microlens; and The position of the composite microlens is at least one of the following: i) inside the gaps between scintillator elements; ii) inside the gaps between trapezoidal scintillator elements; and iii) Over the gaps between the trapezoidal scintillator elements.

7. The imaging detector according to claim 3, in, The array of optical component arrangements and the array of scintillator elements are arranged on opposite sides of the photosensor; wherein the photosensor is photosensitve on both sides; and wherein each optical component arrangement is configured to direct the incident optical radiation towards one or more X-ray pixels coupled to a respective scintillator element; or wherein the array of optical component arrangements and the array of scintillator elements are arranged on the same side of the photosensitive sensor; wherein each optical component arrangement is configured to direct the incident optical radiation passing through the corresponding scintillator element towards one or more X-ray pixels; or Therein, at least one scintillator element has a surface shape configured in such a way that the at least one scintillator element itself acts as a microlens for optical imaging.

8. The imaging detector according to claim 3, in, The array of scintillator elements comprises scintillator elements having: i) Different thickness; ii) different sizes between scintillator elements; iii) a size that is different compared to the size of the sensor pixel; iv) Different distance gaps; v) non-uniform distribution; vi) different radiation conversion materials; and / or vii) different compositions of radiation conversion materials; and wherein the composition of the radiation conversion material is different in at least one of the following: - the doping level of the radiation conversion material; - doping materials; and - Combinations of doping materials.

9. The imaging detector according to claim 1, in, The X-ray scintillator is a continuous scintillator comprising a radiation conversion material.

10. The imaging detector according to claim 4; in, At least one microlens is configured as an optical filter for selectively transmitting light having different wavelengths; and / or Wherein, the light guide is configured as an optical filter for selectively transmitting light having different wavelengths.

11. An imaging detector according to any one of the preceding claims, in, A semi-transmissive and semi-reflective optical mirror (44) is provided; wherein the semi-transmissive and semi-reflective optical mirror is provided as an array of filters (46a), each filter being configured to block one or more X-ray pixels from receiving the incident optical radiation; and / or Wherein, the semi-transparent and semi-reflective optical mirrors are provided as an array of optical switches (46b), each optical switch being configured to enable the incident optical radiation received by one or more X-ray pixels to be selectively switched on and off synchronously with time-interleaved X-ray imaging and optical imaging.

12. The imaging detector according to any one of claims 2 to 10, in, The array of optical component devices includes microlenses having the following items: i) Different focal lengths; ii) Different distance gaps; iii) non-uniform distribution; iv) different sizes between microlenses; and / or v) A size that is different compared to the size of the sensor pixels.

13. The imaging detector according to any one of claims 1 to 10, in, The substrate comprises a flat or substantially flat or curved shape; and Wherein, the substrate comprises silicon, glass or polymer foil.

14. An imaging system (100), comprising: - The imaging detector according to claim 1; - X-ray source (48); as well as - a light source (50); wherein the X-ray source is configured to provide X-ray radiation; wherein the light source is configured to provide optical radiation; and The imaging detector is configured to detect the X-ray radiation to generate X-ray imaging data, and to detect the optical radiation to generate optical imaging data.

15. A method (200) for manufacturing an imaging detector, comprising the steps of: a) forming (210) a substrate; b) forming (212) a photosensitive sensor on the substrate; and c) placing (214) an array of X-ray scintillators and / or optical component devices on the photosensitive sensor and / or on the substrate layer by a pick and place assembly transfer process; Wherein, the photosensitive sensor comprises sensor pixels (20) distributed on the imaging detector; wherein the X-ray scintillator is configured to convert energy of incident X-ray radiation (22) into photons; wherein each optical component arrangement comprises at least one optical component (24) configured to direct incident optical radiation (26) towards the light-sensitive sensor; wherein the sensor pixels include optical pixels (28), each optical pixel being coupled to a corresponding optical component device to receive the incident optical radiation to generate optical imaging data; and The sensor pixels include X-ray pixels (30), which are coupled to the X-ray scintillator to receive converted photons, thereby generating X-ray imaging data.

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