X-ray detector and method of detecting x-ray radiation

Abstract

An X-ray detector and a method of detecting X-ray radiation are disclosed, relating to the field of X-ray detection technology. The X-ray detector includes a semiconductor detector layer coupled with a light emitting diode (LED) layer on an optical side. The detector is characterized by an X-ray side electrode layer deposited on one side of the semiconductor detector layer and an optical side electrode layer, such as transparent indium tin oxide (ITO), on the opposite side. The semiconductor detector layer includes a high atomic number (Z) material with a high density and resistivity (about 10 6 Ω·cm or greater than 10 6 Ω·cm) to effectively absorb X-ray radiation while minimizing dark current. A fiber optic plate is used to direct light generated in the LED layer to an optical detector.

Description

Technical Field

[0001] This application relates to the field of X-ray detection technology, and in particular to an X-ray detector and a method for detecting X-ray radiation. Background Technology

[0002] X-ray microscopy provides high spatial resolution two-dimensional and three-dimensional imaging of samples. This technique implicitly requires high X-ray detection efficiency.

[0003] Some current X-ray microscopes utilize thin scintillator X-ray detectors optically coupled to a charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) camera via an optical microscope. This setup achieves high-resolution imaging by first converting X-rays into light and then detecting that light with a conventional camera.

[0004] However, the optical coupling in a scintillator-optical microscope-camera detection system is not perfect. Light collection efficiency is limited by the finite numerical aperture (NA) of the objective lens and light loss in the optical microscope. This leads to a reduction in the quantum detection efficiency (DQE) of X-ray detection (the so-called quantum sink), and a direct consequence is a reduction in imaging throughput.

[0005] In a typical collection process, scintillator detection systems lose most of the photons generated. For example, a 40X objective with NA=0.65 collects about 3% of the light generated by the scintillator, and objectives with lower NA collect even less. A rough estimate suggests that a system with a 0.65-NA objective and a high-efficiency optics and camera system can collect about 40 photoelectrons from 30 keV X-ray photons, typically collecting these photoelectrons in several adjacent pixels. While increasing the numerical aperture can improve collection efficiency, this comes at the cost of depth of field, which translates to a smaller scintillator thickness and thus reduced X-ray absorption efficiency.

[0006] An alternative approach uses an optical fiber board to directly connect the scintillator to the optical detector. The optical fiber board consists of numerous fine glass fibers, each acting as an individual optical waveguide. These fibers facilitate direct transfer of light from the scintillator's emission plane to the detection plane of the CMOS (e.g., an optical detector chip), thereby efficiently delivering the generated image with high spatial fidelity.

[0007] The purpose of fiber coupling is to enhance light collection efficiency by reducing optical losses typically associated with lens-based systems. Each fiber in the plate maintains spatial resolution by guiding light from a specific point in the scintillator to a corresponding point on the CMOS detector. This direct coupling minimizes light diffusion and preserves image integrity, which is crucial for high-resolution X-ray microscopy.

[0008] Another option for detecting X-rays or high-energy particle beams utilizes semiconductor direct conversion detection materials. Materials such as silicon (Si), gallium arsenide (GaAs), cadmium telluride (CdTe), perovskite-structured semiconductors, or other active materials are used instead of scintillators. Absorption of X-ray photons generates electron-hole pair clouds, and free charge carriers are then guided to a pixelated electron detector via an applied bias voltage. Multiple electron-hole pair clouds can be integrated and read out, or individual charge cloud pulses can be detected and counted. Silicon-based direct detection detectors are only useful for low X-ray energies (e.g., <20 keV) due to silicon's low stopping power. For harder X-ray radiation, photon counting detectors with high atomic number semiconductors (such as CdTe and GaAs) are used, but these are relatively expensive.

[0009] For example, in U.S. Patent Application Publications US2021 / 0311211 A1 and US2023 / 0165541 A1 by Xiaochao Xu and Christoph Graf Vom Hagen (which are incorporated herein by reference), free charge carriers are directed to a spatial light modulator, such as a liquid crystal (LC) light valve. The charge of the carrier modulates the light valve, which is then illuminated by an external light source of an optical microscope. This configuration can reduce light loss in the optical system of current scintillator-optical microscope-camera inspection systems.

[0010] Recently, Philipp Brenner and Xiaochao Xu's paper, "Semiconductor X-ray Detector with Light Emitting Layer and Method Therefor," WO 2023 / 133491 A1 (incorporated hereby by reference), describes a detector that incorporates a light-emitting diode (LED) emitting layer into a direct-conversion detector for X-ray microscopy. Coating the semiconductor material allows electron-hole pairs to generate visible light in the LED layer, which is then observed using the classical optical path of X-ray microscopy. A major advantage is the ability to use thick active material while still achieving high resolution, as light generation occurs only within the LED layer. Therefore, resolution and sensitivity are no longer coupled. However, in X-ray microscopy, the LED is typically observed through a microscope objective, so only a small detection area is common. Summary of the Invention

[0011] This invention relates to the use of X-ray LED detectors, such as in large-area X-ray detectors. The X-ray LED detector is coupled to an optical fiber plate, which is then further connected to a conventional detector for visible light, such as a CMOS or CCD optical sensor.

[0012] Generally, according to one aspect, the present invention is characterized by an X-ray detector comprising: a semiconductor detector layer configured to absorb X-ray radiation and generate charge carriers in response thereto, the semiconductor detector layer having an X-ray side and an optical side; an X-ray side electrode layer disposed on the X-ray side of the semiconductor detector layer; a light-emitting diode (LED) layer disposed on the optical side of the semiconductor detector layer, the LED layer being configured to receive charge carriers from the semiconductor detector layer and emit light; an optical side electrode layer disposed opposite to the semiconductor detector layer on the LED layer, the optical side electrode layer including a transparent conductive material; an optical fiber panel (FOP) optically coupled to the optical side electrode layer, the FOP being configured to guide the emitted light while maintaining spatial resolution; and a spatial resolution sensor positioned to receive the light guided by the FOP and generate an image corresponding to the X-ray radiation distribution.

[0013] In the example, the semiconductor detector layer comprises a high atomic number (Z) semiconductor material selected from silicon, amorphous selenium (a-Se), gallium arsenide (GaAs), zinc cadmium telluride (CdZnTe), cadmium telluride (CdTe), and perovskite semiconductor crystals. The semiconductor detector layer typically has a thickness ranging from about 2 micrometers to about 10 millimeters.

[0014] Spatial resolution sensors typically include two-dimensional pixelated CMOS or CCD chips.

[0015] In addition, an impregnated oil layer can be positioned between the FOP and the optical side electrode layer to enhance optical coupling through adhesive and refractive index matching.

[0016] In some embodiments, the FOP has an optical fiber diameter that is significantly smaller than the pixel size of a spatially resolved sensor in order to maintain high imaging resolution.

[0017] The tapered FOP can also be configured to adjust the effective pixel size by zooming in or out of the image.

[0018] Typically, FOPs are made of lead glass, thick enough to protect spatially resolved sensors from X-ray radiation.

[0019] In addition, multiple modules of the detector can be pieced together to form a larger active area, with each module having its own bias voltage source and LED layer.

[0020] In general, according to another aspect, the present invention is characterized by a method for detecting X-ray radiation, the method comprising absorbing X-ray photons in a semiconductor detector layer to generate charge carriers, applying an electric field across the semiconductor detector layer using an X-ray side electrode layer and an optical side electrode layer, transferring at least one type of charge carrier to a light-emitting diode (LED) layer disposed on the optical side of the semiconductor detector layer, injecting the charge carrier into the LED layer to induce radiative recombination and emit light, guiding the emitted light through an optical fiber panel (FOP) to a spatial resolution sensor, and detecting the guided light with the spatial resolution sensor to generate an image corresponding to the X-ray radiation distribution.

[0021] The above and other features of the invention (including various novel details of combinations of structures and components) and other advantages will now be described in more detail with reference to the accompanying drawings, which are set forth in the claims. It will be understood that the specific methods and apparatus embodying the invention are shown by way of illustration and not as limitations thereof. The principles and features of the invention can be used in various and many embodiments without departing from the scope of the invention. Attached Figure Description

[0022] In the accompanying drawings, reference numerals refer to the same parts throughout the different views. The drawings are not necessarily drawn to scale, but rather focus on illustrating the principles of the invention. In the accompanying drawings:

[0023] Figure 1A and Figure 1B This is a side view showing a semiconductor light-emitting diode (LED) X-ray detector with fiber optic plate coupling;

[0024] Figure 2 A schematic side perspective view of a layer illustrating an exemplary GaAs detector / LED / FOP device; and

[0025] Figure 3 This is a schematic diagram of an X-ray microscope to which the present invention can be applied. Detailed Implementation

[0026] The invention will now be described more fully below with reference to the accompanying drawings, in which illustrative embodiments of the invention are shown. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0027] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Furthermore, all conjunctions used should be understood in the most inclusive sense possible. Therefore, the word “or” should be understood as having the definition of logical “or” rather than logical “exclusive or”, unless the context explicitly requires otherwise. Additionally, the singular forms and the articles “a,” “an,” and “the” are intended to also include the plural forms, unless otherwise explicitly required. It should also be understood that, when used in this specification, the terms includes, comprises, including, and / or comprising specify the presence of the stated feature, integral, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof. Further, it will be understood that when an element comprising a component or subsystem is mentioned and / or shown as connected or coupled to another element, it may be directly connected or coupled to the other element or there may be intermediate elements present.

[0028] It should be understood that although terms such as "first" and "second" are used herein to describe different elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. Therefore, without departing from the teachings of the invention, the elements discussed below may be referred to as second elements, and similarly, second elements may be referred to as first elements.

[0029] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will be further understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant field and will not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0030] Figure 1A The basic arrangement of the semiconductor light-emitting diode (LED) X-ray detector 12 is shown.

[0031] The detector 12 includes an LED layer 92 disposed on one side of a semiconductor detector layer 74. An X-ray side electrode layer 72 is deposited on the X-ray side of the semiconductor detector layer 74. On the optical side of the semiconductor detector layer 74 is the LED layer 92, followed by an optical side electrode layer 94 such as a transparent indium tin oxide (ITO) layer.

[0032] Semiconductor detector layer 74 is typically a semiconductor with a relatively high effective atomic number Z and density to effectively stop and absorb X-ray radiation. The resistivity should be high, having a value of approximately or greater than 10. 6 The value of Ω·cm is used to reduce dark current. Furthermore, at least one type of excitation charge carrier (electron or hole) can be transported across the thickness of semiconductor layer 74 before recombination in the absorption layer; that is, the excitation charge carriers for injection into LED layer 92 have a relatively high mobility-lifetime product. μτ This is a characteristic of semiconductor materials, where µ is the material's mobility and τ is the carrier's lifetime. For better detector performance, a larger τ is preferred. μτ Other requirements are similar to those required for other semiconductor X-ray detectors, such as low polarization and stability over time and under other conditions.

[0033] The semiconductor layer 74 will typically have a thickness ranging from about a few micrometers (such as between 2 and 5 micrometers) to 10 mm. In one embodiment, the semiconductor layer 74 is between about 0.5 mm and 2 mm. That is, for higher energy, a thicker layer is better. In different embodiments, the layer is silicon, amorphous selenium (a-Se), GaAs, CdZnTe, CdTe, or crystalline and amorphous perovskite semiconductor crystal materials (ABX3).

[0034] The fiber optic panel (FOP) 150 guides the light generated by the LED layer 92 to produce a large-area X-ray detector. Using X-ray LEDs, the FOP-coupled X-ray detector can potentially improve one or both of quantum efficiency and imaging resolution (with the fiber diameter remaining constant).

[0035] Spatial resolution sensor 152 detects light from fiber optic panel 150. Sensor 152 is preferably a two-dimensional pixelated CMOS or CCD chip. Specifically, a sensor pre-connected to FOP 150 can be used, and the X-ray LED 92 can be easily placed on the sensor by pressing the X-ray LED 92 against FOP 150 via a holding device such as a clamp, so that the light generated in the LED layer 92 can be coupled into a separate waveguide of FOP 150.

[0036] To image the X-ray radiation distribution generated in LED layer 92 with sufficient resolution, an fiber optic plate (FOP) with a fiber diameter significantly smaller than the pixel size of sensor 152 is selected. For example, FOPs with fiber diameters in the range of 3 µm or 6 µm exist, which can be used for sensor 152 with pixel sizes in the range of, for example, 25 µm or larger. Of course, in the case of these small fiber diameters, significantly larger sensor pixel sizes in the range of, for example, 50 µm, 100 µm, or 200 µm or larger are also available.

[0037] The working mechanism is as follows. A charge cloud (a cloud of electron-hole pairs) is generated within the thick semiconductor layer 74 through the absorption of X-ray photons or particles. Electrons and holes travel in opposite directions due to the electric field applied by the bias voltage source 96, which passes through the X-ray side electrode layer 72 and the optical side electrode layer 94. The voltage provided by the voltage source is typically high, such as greater than 10-20 volts (V). Currently, for a 2 mm thick semiconductor layer, the voltage is greater than 100 V, such as 200-300 V or higher.

[0038] Based on the polarity of voltage source 96, one type of charge carrier is injected into the thin emitting region of LED layer 92. The structure of LED layer 92 is tailored for efficient radiative recombination. See Li N, Han K, Spratt W, Bedell S, Ott J, Hopplean M et al., Ultra-low-power sub-photon-voltage high-efficiency light-emitting diodes, Nature Photonics, 2019;13(9):588-592. Radiative recombination results in the emission of photons in the light wavelength (such as visible light photons), which propagate through optical side electrode layer 94 and can then be guided to optical detector 152 by FOP 150.

[0039] A key requirement for LED layer 92 is its efficient operation over a wide range of charge carriers injected into it. The amount of injected charge carriers depends on the amount of X-ray photons absorbed and therefore varies throughout operation. Specific layer stacking and growth conditions must be considered to ensure efficient operation at low charge carrier injection densities. See Li et al.

[0040] There are advantages to using organic light-emitting diode (OLED) layers as LED layers 92. OLEDs exhibit high efficiency at low charge carrier injection densities, while an efficiency roll-off is typically observed at high charge injection densities. Another advantage of using OLEDs is that these layers can be deposited on different absorbing substrates by thermal evaporation, because lattice matching does not need to be considered as in the epitaxial techniques required for inorganic semiconductors.

[0041] In one embodiment, detector 12 uses a GaAs-based semiconductor detector absorption layer 74. For the LED layer 92, its associated alloys (AlGaAs and InGaAs) are used to form a heterostructure. One advantage of GaAs is that it has one of the highest radiative recombination rates among commonly available semiconductor materials. Furthermore, due to its widespread availability, the technology used to manufacture such LEDs is mature and readily available.

[0042] LED-based detectors will cover a wide range of X-ray flux levels, where the generated X-ray current is quite small at low flux levels, or for single-photon detection. Typical LEDs have relatively low luminous efficiency at low drive currents because nonradiative recombination exceeds radiative recombination at low charge injection rates.

[0043] In one example, LED layer 92 is designed for high efficiency at ultra-low currents to overcome the drawbacks of conventional LEDs designed to operate at higher injection currents. In one embodiment, a single quantum well (QW) is used in conjunction with a specially designed well and cladding. These improvements are achieved via two mechanisms: (1) a high-quality InGaAs / InGaP or GaAs / InGaP interface that reduces the interfacial recombination velocity (IRV), and (2) a large valence band shift. This causes the hole density p within QW to be much larger than the electron density n (or a large conduction band shift). (This makes the electron density n within QW much larger than the hole density p). See Li et al.

[0044] In another example, LED layer 92 has an InGaP / GaAs / InGaP double heterojunction, which has been shown to have high quantum efficiency. See Li et al. In a specific example, the InGaP bandgap is 1.90 eV, and the InGaP / GaAs conduction band offset is 0.10 eV and the valence band offset is 0.38 eV.

[0045] Then, the spatial distribution of light generated in LED layer 92 is maintained as it is transferred to individual pixels of sensor 152 via FOP 150.

[0046] Figure 1BAlternative coupling options are shown. An impregnation oil (or other impregnation medium) layer 154 is used between the FOP 150 and the X-ray LED, and specifically between the FOP 150 and the transparent electrode 94, such that it is adhered to the FOP 150 by an adhesive. Layer 154 also provides refractive index matching (e.g., the refractive index of layer 154 is within ±0.15 of the incident plane of the FOP). The thickness of layer 154 is typically 1 µm – 50 µm. There are no disadvantages, especially when using pixel sizes significantly larger than the typical size of the visible light generation point in the LED layer (i.e., <20 µm) (e.g., a 100 µm sensor pixel size), because the generated light must travel a greater distance in the electrode layer or impregnation oil. The blurring introduced by the additional impregnation oil layer will still be smaller than the sensor pixel size, and the FOP delivery will not introduce any significant additional blurring.

[0047] One way to influence the effective area of ​​an X-ray detector is to use a tapered field-of-aperture (FOP), which effectively reduces or enlarges the image generated by the X-ray LED to control the effective pixel size of the X-ray detector in the desired direction. For example, there are tapered FOPs with a 4x (reduced) magnification that can be used to couple a large-area X-ray LED to a smaller sensor. Alternatively, the tapered FOP can be mounted in another direction to increase the resolution, for example, to achieve an effective pixel size of 25 µm with an actual 100 µm pixel size. In this way, the tapered FOP can be used to address any mismatch between the X-ray and optical detector sizes.

[0048] One drawback of active semiconductor materials is that they are generally not mass-produced in large sizes. Typical sizes for single-crystal perovskites are in the range of approximately 50 millimeters (mm). However, to achieve active area sizes in the hundreds of millimeters range, multiple smaller components can be tiled together to fill a larger area of ​​an optical sensor or field-expanded (FOP). Several modules can have their own connectors to supply bias voltage and their own LED layers. Alternatively, a single electrode and a single LED layer can be used at the front and rear of the active material. Tiling typically introduces small gaps between modules, for example, due to non-ideal edge characteristics. The effects of these edge effects in X-ray images will manifest as changes in the sensitivity of the corresponding pixels at the transitions, which can be compensated for by flat-field correction (i.e., by recording one or more images without any objects and compensating for static deviations in the images). The non-linear behavior of the pixels can also be compensated when using multiple images for different exposure conditions (e.g., different readout times due to pre-filters, different attenuations).

[0049] A preferred method for constructing a fiber optic detector with X-ray LEDs is to use a fiber optic plate made of lead glass. By selecting the thickness of the lead glass FOP, typical radiation-sensitive sensors can be protected from X-ray radiation. The thicker the FOP, the higher the X-ray energy the detector can withstand.

[0050] Figure 2 A specific embodiment of detector 12 is shown.

[0051] The semiconductor detector absorption layer 74 is a thick GaAs layer used for X-ray detection. The thickness of a thick GaAs layer typically ranges from 0.1 micrometers to over 100 micrometers. However, note that a thickness of 50 µm was used for simulation purposes. The semiconductor detector absorption layer 74 is located on the X-ray side electrode layer 72. The LED heterostructure layer 92 comprises 200 nanometers (nm) of n-type In... 0.49 Ga 0.51 P-contact layer 92A, followed by 50 nm In. 0.49 Ga 0.51 A P-layer 92B, a 7 nm GaAs layer 92C, and another 50 nm In layer. 0.49 Ga 0.51 A p-type In layer 92D is used to form a double heterojunction. A 200 nm thick p-type In layer is used before the optical side electrode layer 94. 0.49 Ga 0.51 As hole contact layer 92E and 30 nm thick p + Type GaAs hole contact layer 92F.

[0052] Regarding the context, Figure 3 This is a schematic diagram of an X-ray CT microscope system 200. The X-ray detection system 100 and its semiconductor LED X-ray detector 12 can be applied to the X-ray CT microscope system 200.

[0053] Nevertheless, the present invention is applicable to charged particle analysis systems and non-microscope systems.

[0054] Microscope 200 typically includes an X-ray imaging system having an X-ray source system 202 and a stage system 210. The X-ray source system 202 generates a multicolor X-ray beam 102 (which is then filtered or may generate a monochromatic X-ray beam 102). The stage system 210 has an object holder 212 for holding and positioning an object 214 so that the object 214 can be scanned in the stationary beam 102. An X-ray detection system 100 detects the beam 102 after it has been modulated by the object 214. A base, such as a platform or optical stage 207, provides a stable foundation for microscope 200.

[0055] Generally speaking, the stage system 210 has the ability to position and rotate the object 214 in the beam 102.

[0056] Source system 102 can be any kind of radiation source with suitable energy or energy range, such as an open or closed X-ray tube with a transmitting or reflecting target. In addition, other types of X-ray sources (such as synchrotron radiation) are also possible.

[0057] The X-ray beam generated by source 202 is preferably modulated to suppress unwanted radiation energy or wavelengths, especially when using a laboratory X-ray source. For example, an energy filter (designed to select the desired X-ray wavelength range (bandwidth)) held in filter wheel 260 is used to eliminate or attenuate unwanted wavelengths present in the beam. Modulation is also often provided by collimators or condensers and / or X-ray lenses (such as plate lenses).

[0058] When object 214 is exposed to X-ray beam 102, the X-ray photons that pass through the object form a modulated X-ray beam received by detection system 100. In some other examples, zone plate objective X-ray lenses are used to form an image on X-ray detection system 100.

[0059] Typically, a magnified projected image of object 214 is formed on detection system 100. The geometric magnification is equal to the ratio of the source-to-detector distance 304 to the source-to-object distance 302.

[0060] The operation of system 200 and the scanning of object 214 are controlled by computer system 224, which typically includes an image processor subsystem and a controller subsystem. The computer system is used to set the bias voltage of detector 12 and read out the optical images detected by sensor 152 of detection system 100. With the possible assistance of its image processor, computer system 224 receives a set of images from detection system 100 associated with each rotational angle of object 214 to establish a scan.

[0061] It should be noted that the computer system does not need to be a single device. For example, a single-board computer or microcontroller can be used as the control system of microscope system 200. A separate computer can be used to process images generated by sensor 152 to generate spatially and spectrally resolved images or projections of the object, and / or to perform tomographic reconstruction of the object based on multiple projections. In fact, sensor images can be stored and subsequently processed or reprocessed to generate object images and reconstructions. Therefore, a dedicated computer, such as a graphics processing unit (GPU), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), general-purpose computer, or some combination of these or other computer systems, will be included as part of computer system 224 to process images. Furthermore, these computer systems can also be integrated within X-ray inspection system 100.

[0062] Although the invention has been specifically shown and described with reference to its preferred embodiments, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims.

Claims

1. An X-ray detector, comprising: A semiconductor detector layer configured to absorb X-ray radiation and generate charge carriers in response thereto, the semiconductor detector layer having an X-ray side and an optical side; X-ray side electrode layer, wherein the X-ray side electrode layer is disposed on the X-ray side of the semiconductor detector layer; A light-emitting diode (LED) layer is disposed on the optical side of the semiconductor detector layer, and the LED layer is configured to receive charge carriers from the semiconductor detector layer and emit light; An optical side electrode layer is disposed on the LED layer opposite to the semiconductor detector layer, and the optical side electrode layer comprises a transparent conductive material; An optical fiber panel (FOP) optically coupled to the optical side electrode layer, the FOP being configured to guide emitted light while maintaining spatial resolution; as well as A spatial resolution sensor is positioned to receive light guided by the FOP and generate an image corresponding to the X-ray radiation distribution.

2. The X-ray detector according to claim 1, wherein, The semiconductor detector layer comprises semiconductor materials selected from silicon, amorphous selenium (a-Se), gallium arsenide (GaAs), zinc cadmium telluride (CdZnTe), cadmium telluride (CdTe), and perovskite semiconductor crystals.

3. The X-ray detector according to claim 1, wherein, The semiconductor detector layer has a thickness ranging from 2 micrometers to 10 millimeters.

4. The X-ray detector according to claim 1, wherein, The spatial resolution sensor includes a two-dimensional pixelated CMOS or CCD chip.

5. The X-ray detector of claim 1 further includes an impregnation oil layer positioned between the FOP and the optical side electrode layer to enhance optical coupling via an adhesive.

6. The X-ray detector according to claim 1, wherein, The FOP has a fiber diameter significantly smaller than the pixel size of the spatial resolution sensor in order to maintain high imaging resolution.

7. The X-ray detector according to claim 1, wherein, The FOP is a tapered fiber optic panel configured to adjust the effective pixel size by zooming in or out of the image.

8. The X-ray detector according to claim 1, wherein, The FOP is made of lead glass, and the thickness of the lead glass is sufficient to protect the spatial resolution sensor from X-ray radiation.

9. The X-ray detector according to claim 1, wherein, Multiple modules of the detector are pieced together to form a larger active area, each module having its own bias voltage source and LED layer.

10. The X-ray detector according to claim 1, wherein, The magnification or reduction is between 0.25x and 4x.

11. A method for detecting X-ray radiation, comprising: X-ray photons are absorbed in the semiconductor detector layer to generate charge carriers; An electric field is applied across the semiconductor detector layer using an X-ray side electrode layer and an optical side electrode layer; At least one type of charge carrier is transferred to a light-emitting diode (LED) layer disposed on the optical side of the semiconductor detector layer; The charge carrier is injected into the LED layer to induce radiative recombination and emit light; The emitted light is guided through the fiber optic panel (FOP) to reach the spatial resolution sensor; as well as The guided light is detected using the spatial resolution sensor to generate an image corresponding to the X-ray radiation distribution.

12. The method of claim 11, further comprising enhancing the optical coupling between the LED layer and the FOP by applying an impregnation oil layer.

13. The method according to claim 11, wherein, The semiconductor detector layer comprises a high-Z material with high resistivity and mobility lifetime product (μτ) to ensure efficient charge carrier transport and reduced dark current.

14. The method of claim 11, further comprising using a tapered FOP to adjust the effective pixel size by magnifying or reducing the emitted light image.

15. The method according to claim 11, wherein, The FOP is made of lead glass to protect the spatial resolution sensor from X-ray exposure.

16. The method of claim 11 further comprises assembling multiple detector modules to cover a larger area and compensating for edge effects using flat-field correction techniques.

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