Abstract: A counting x-ray detector includes, in a stack arrangement, a converter element for conversion of x-ray radiation into electrical charges and an electrode. The electrode is connected to the converter element electrically-conductively in a planar manner. The electrode is embodied at least partly transparently. The electrode includes the following layers: an electrically-conductive contact layer, an electrically-conductive first intermediate layer, an electrically-conductive high-voltage layer, and an illumination layer.

Abstract: A halide material, such as scintillator crystals of LaBr3:Ce and SrI2:Eu, with a passivation surface layer is disclosed. The surface layer comprises one or more halides of lower water solubility than the scintillator crystal that the surface layer covers. A method for making such a material is also disclosed. In certain aspects of the disclosure, a passivation layer is formed on a surface of a halide material such as a scintillator crystal of LaBr3:Ce of SrI2:Eu by fluorinating the surface with a fluorinating agent, such as F2 for LaBr3:Ce and HF for SrI2:Eu.

Abstract: Various embodiments of a 3D high resolution X-ray sensor are described. In one aspect, an indirect X-ray sensor includes a silicon wafer that includes an array of photodiodes thereon with each of the photodiodes having a contact on a front side of the silicon wafer and self-aligned with a respective grid hole of an array of grid holes that are on a back side of the silicon wafer. Each of the grid holes is filled with a scintillator configured to convert beams of X-ray into light. The indirect X-ray sensor also includes one or more silicon dies with an array of photo-sensing circuits each of which including a contact at a top surface of the one or more silicon dies. Contact on each of the photodiodes is aligned and bonded to contact of a respective photo-sensing circuit of the array of photo-sensing circuits of the one or more silicon dies.

Abstract: A detector that detects properties of geological formation includes a first volume and a second volume each comprising Helium-3 gas. The detector includes a gas electron multiplier having a mesh plate disposed between the first volume and the second volume. The mesh plate creates an electric field that multiplies electrons of the second volume based on epithermal neutrons in the second volume. The detector includes at least one anode configured to receive electrons based on thermal neutrons in the first volume and epithermal neutrons in the second volume.

Abstract: A radiation detector is provided including a cathode, an anode, and a semiconductor wafer. The semiconductor wafer has opposed first and second surfaces. The cathode is mounted to the first surface, and the anode is mounted to the second surface. The semiconductor wafer is configured to be biased by a voltage between the cathode and the anode to generate an electrical field in the semiconductor wafer and to generate electrical signals responsive to absorbed radiation. The electrical field has an intensity having at least one local maximum disposed proximate to a corresponding at least one of the first surface or second surface.

Abstract: According to one embodiment, a display device includes a first scanning line, a signal line, a second pixel electrode, a first pixel electrode, a second thin-film transistor, a first line and a second line. The first line is connected to the second pixel electrode, and extends through a region facing the first pixel electrode to the first scanning line side. The first line and a second semiconductor layer of the second thin-film transistor are provided on a first insulating film and are formed of a same material. The second line connects the first line and a fourth electrode of the second thin-film transistor.

Abstract: This invention describes a novel solution to conserve battery and to overcome cold-start artifacts by maintaining the pixel charge traps at a stable value at all times. The design of NIP photodiode and TFT combination requires very low current (in order of hundreds of ?A) to stay biased at all times. This allows the pixel charge traps to be easily maintained at a stable value with low power consumption. Power consumption is kept at a minimum by keeping all panel electronics off and only the pixels biased. In addition, keeping the pixels biased helps to overcome the cold-start artifact in the very first image.

Abstract: The imaging device includes a sensor substrate, a light-blocking substrate, a light-collecting substrate, a sealing material, and a light-transmitting member. The light-transmitting member includes a light-transmitting base disposed to be in contact with either the sensor substrate or the light-blocking substrate, and a light-transmitting resin which is filled between the base and the sensor substrate or the light-blocking substrate. A void is formed in at least a part of a space between the sealing material and the light-transmitting member.

Abstract: A device for detecting radiation particles comprising at least one sensor for sensing radiation particles, capable of supplying an electrical pulse when it is traversed by at least one radiation particle, and at least one detection circuit comprising a voltage-controlled oscillator to which said electrical pulse originating from the sensor is supplied as the control voltage. The voltage-controlled oscillator is a ring oscillator.

Abstract: An adding unit adds an input signal generated in a signal generating unit connected to a specific pixel electrode portion out of pixel electrode portions arranged around a certain pixel electrode portion to an input signal generated in a signal generating unit connected to the certain pixel electrode portion. A discriminating unit discriminates whether a carrier input pattern coincides with any one of a plurality of discrimination patterns, and the carrier input pattern indicates, per the pixel electrode portion, presence of any carrier received in the certain pixel electrode portion and the pixel electrode portions arranged around the certain pixel electrode portion. The counting unit increments the number of photons in the case where the discriminating unit discriminates that the carrier input pattern coincides with any one of the discrimination patterns and further the input signal output from the adding unit after addition has a value exceeding a predetermined threshold.

Abstract: A multi-layer charged particle beam characterization system is disclosed, and method for using the same. A typical embodiment includes a plurality of two-sided metal plates, arranged as a stack, each metal plate having an electrical contact tab extending from at least one common edge of the metal plate, and a plurality of insulator films disposed between adjacent metal plates, each insulator film sized to match its corresponding metal plate. The tabs are coupled to a printed circuit board and connected to an external electrical connector to register a number of metal plates and insulator layers through which a charged particle beam has penetrated.

Abstract: A detector for measuring scanning ion beams in radiation therapy sequentially includes a first high voltage electrode, a first spacing member, and a segmented electrode. The first spacing member is connected to the first high voltage electrode and the segmented electrode to form a first ionization cavity. The first ionization cavity is formed with a plurality of first reading electrodes and a plurality of second reading electrodes therein. A second spacing member and a second high voltage electrode are further sequentially disposed. The second spacing member is connected to the second high voltage electrode and the segmented electrode to form a second ionization cavity. The first reading electrodes and the second reading electrodes are respectively formed in the first ionization cavity and the second ionization cavity. With the first reading electrodes and the second reading electrodes in different directions, highly accurate space resolution, space dosage and scanning speed are achieved.

Abstract: A device for producing electricity. The device comprises an indium gallium phosphide semiconductor material comprising a plurality of indium gallium phosphide material layers each layer having different dopant concentrations and doped with either n-type dopants or p-type dopants, a first terminal on a first surface of the semiconductor material, a beta particle source proximate the first surface for emitting beta particles that penetrate into the semiconductor material, and a second terminal on a second surface of the semiconductor material; the semiconductor material for producing current between the first and second terminals responsive to the beta particles penetrating into the semiconductor material.

Abstract: Disclosed are systems, devices and methodologies related to calibration of an ion based imaging apparatus such as a proton computed tomography scanner. In some implementations, energy degrader plates having known water-equivalent thickness (WET) values can be introduced to an ion beam to introduce different energy degradation settings. Energy detector responses to individual ions subject to such energy degradation settings can be obtained. Such responses can be normalized and correlated to water-equivalent path lengths (WEPL) of the ions based on the known WET values. Such calibration utilizing degrader plates can be performed relatively quickly and can yield accurate WEPL values that facilitate estimation of, for example, a CT image based on relative stopping power of an object.

Abstract: An apparatus according to the present invention in which a first substrate including a photoelectric conversion element and a gate electrode of a transistor, and a second substrate including a peripheral circuit portion are placed upon each other. The first substrate does not include a high-melting-metal compound layer, and the second substrate includes a high-melting-metal compound layer.

Abstract: A radiation imaging apparatus, comprising a plurality of sensors and a driving unit, each sensor including a detection element, a sampling unit and a reset unit, wherein the driving unit performs an operation of causing the reset unit to initialize the detection element, an operation of causing the sampling unit to sample a signal from the detection element in accordance with radiation irradiation started after the operation of initializing, and an operation of outputting a signal sampled by the operation of sampling, and wherein the driving unit changes, in accordance with a frame rate, a timing of the operation of outputting while maintaining constant a time from the operation of initializing to the operation of sampling.

Abstract: Energy storage apparatus comprising: a porous conductor substrate, an insulator layer in contact with inner surfaces of the porous conductor substrate, and a conductor layer in contact with outer surfaces of the insulator layer.

Abstract: A device for monitoring and controlling water disinfecting systems having at least one broadband UV emitter arranged in a channel, wherein the device has at least one sensor, which is arranged in the water at a distance from the broadband UV emitter, and wherein the sensor is connected to a control unit, which is set up to control the output of the broadband UV emitter or the volumetric flow of water through the channel, wherein the sensor has a maximum sensitivity to UV radiation in a wavelength range between 200 nm and 240 nm.

Abstract: An imaging system (100) includes a direct conversion detector pixel (111) that detects radiation traversing an examination region and generates an electrical signal indicative thereof, wherein the signal includes a persistent current, which is produced by a direct conversion material of the pixel and which shifts a level of the signal. A persistent current estimator (116) estimates the persistent current and generates a compensation signal based on the estimate. A pre-amplifier (112) receives the signal and the compensation signal, wherein the compensation signal substantially cancels the persistent current, producing a persistent current compensated signal, and that amplifies the compensated signal, generating an amplified compensated signal. A shaper (114) generates a pulse indicative of energy of the radiation illuminating the direct conversion material based on the amplified compensated signal.

Abstract: The detection surface of each of a plurality of detection elements is arranged on an arc along a diffractometer circle (reference circle). This allows each detection element to detect X-rays diffracted by a specimen at the focal position. Because this prevents errors in the X-ray intensity detected by each detection element, more accurate diffraction information can be obtained. As a result, a more accurate analysis can be performed in less time by detecting X-rays diffracted by the specimen using a plurality of detection elements.

Abstract: A card dealing system incorporating playing cards with rank and suit information encoded thereon via micro-dots, and a shoe capable of reading such micro dots as a playing card is drawn from the shoe. A game controller unit determines the location of the micro-dots on the playing card, and determines the rank and suit information therefrom. The game controller thereby monitors the progress and status of a card game.

Abstract: An apparatus for recognizing a position of a crystal in a nuclear detector, including: a silicon semiconductor detector array arranged in a crystal array in the nuclear detector, where each row/or column of silicon semiconductor detectors is configured to output a sum of voltages outputted by the silicon semiconductor detectors in the row/or column at a row/or column signal output end; row signal comparing modules, one to one correspondingly connected to each row signal output end and configured to obtain a row comparison result for each row of silicon semiconductor detectors; column signal comparing modules, one to one correspondingly connected to each column signal output end and configured to obtain a column comparison result for each column of silicon semiconductor detectors; and a crystal position recognizing module configured to recognize a position of a crystal hit by a photon according to each row comparison result and each column comparison result.

Abstract: The present invention generally relates to a radiation sensor for use particularly in, but by no means exclusively, in measuring radiation dose in photon or electron fields such as for radiation medicine, including radiotherapy and radiation based diagnosis. According to the present invention, there is provided a semiconductor radiation detector comprising a radiation sensitive detector element arranged such that it forms a continuous radiation sensitive portion having surfaces oriented in at least two non-parallel directions.

Abstract: A method of producing a partial luminaire includes arranging at least one semiconductor chip that emits electromagnetic radiation on a substrate, and applying an elastic waveguide, disposed downstream of the at least one semiconductor chip in an emission direction, such that the elastic waveguide projects at at least one of its side surfaces beyond the substrate.

Abstract: Optical proximity sensors, methods for use therewith, and systems including optical proximity sensor are described herein. Such an optical proximity sensor includes a light source and a light detector, wherein the light detector includes a plurality of individually selectable photodiodes (PDs). During a calibration mode, individual PDs of the plurality of PDs of the light detector are tested to identify which PDs are crosstalk dominated. During an operation mode, the PDs of the light detector that were not identified as being crosstalk dominated are used to produce a light detection value or signal that is useful for detecting the presence, proximity and/or motion of an object within the sense region of the optical proximity sensor. By not using the PDs that were identified as being crosstalk dominated, the signal-to-noise ratio of the light detection value or signal is improved compared to if the crosstalk dominated PDs were also used.

Abstract: A method of fabricating a pixelated imager and structure including a substrate with a bottom contact layer and active element blanket layers deposited on the bottom contact layer. The blanket layers are separated into an array of active elements with trenches isolating adjacent active elements in the array. A dielectric passivation/planarization layer is positioned over the array of active elements. An array of active element readout circuits overlies the passivation/planarization layer above the trenches with one active element readout circuit coupled to each active element of the array of active elements. Each active element and coupled active element readout circuit defines a pixel and the array of active elements and the coupled array of active element readout circuits defines a pixelated imager, and the readout circuit coupled to each active element includes at least one TFT with an active channel comprising a metal-oxide semiconductor material.

Abstract: The invention provides a semiconductor detector, and the semiconductor detector comprises a semiconductor crystal, a cathode, an anode and at least one ladder electrode; the semiconductor crystal comprises a top surface, a bottom surface and at least one side; the cathode, the anode and the ladder electrode are conductive thin films deposited on a surface of the semiconductor crystal; the cathode is disposed on the bottom surface of the semiconductor crystal, the anode is disposed on the top surface of the semiconductor crystal, the ladder electrode is disposed on the at least one side of the semiconductor crystal; and the ladder electrode comprises a plurality of sub-electrodes. As compared to the prior art, the semiconductor detector can improve the energy resolution.

Abstract: A method is provided including acquiring detection events with a radiation detector that includes a semiconductor plate. Electrons and holes are generated in the semiconductor plate responsive to absorption of ionizing radiation. The holes including groups of holes having different effective masses for corresponding different valence energy bands. The method also includes optically coupling infrared (IR) radiation into the semiconductor plate of the radiation detector. The IR radiation has at least one wavelength selected from a spectral range including wavelengths to which the semiconductor plate is partially transparent. The wavelengths of the IR radiation are configured to excite at least some of the holes from a first group at a first valence energy band to a second group at a second valence energy band, with the holes of the second group having lower effective masses than corresponding holes of the first group.

Abstract: The present disclosure provides an X-ray flat panel detector including: a base substrate; thin film transistors (TFTs), a pixel electrode layer, photodiodes, a transparent electrode layer, and an X-ray conversion layer which are arranged on the base substrate; and an electric field application portion configured to generate an electric field, wherein the photodiodes are arranged in the electric field, and a moving direction of negative charges when visible light rays are converted to electrical signals by the photodiodes is substantially same as a direction of the electric field. In this detector, it is applied a direction of the electric field which is substantially same as the moving direction of negative charges in the photodiode, so that movement of holes and electrons of the photodiode may be accelerated under an influence of the electric field, and thus the electrical signal may promptly arrive at the pixel electrode.

Abstract: A system having an X-radiation generator; an X-radiation detector; and a portable computing device. The X-radiation detector has a first wireless communication module, and a non-volatile memory. The X-radiation detector is configured to: self-trigger acquisition of an X-radiation image, store the acquired X-radiation image, and transmit the X-radiation image (or a lower-resolution version) via the first wireless communication module. The portable computing device has a second wireless communication module, and a digital screen. The portable computing device is configured to receive the X-radiation image via the second wireless communication module that communicates with the first wireless communication module, display the X-radiation image on the digital screen, enable a user to select whether to discard the X-radiation image or to transmit the X-radiation image to a server, and responsive to the user selecting to transmit the X-radiation image to the server, transmit the X-radiation image to the server.

Abstract: Improved X-ray detectors are provided in a cross-strip geometry with better resolution than the electrode spacing. The basic idea is analog charge cloud reconstruction. An important practical aspect of this work is rotating the electrode pattern by about 45 degrees relative to the detector slab, which provides several performance benefits (equal length for all electrodes and greater ease of integration into vertical stacks etc.) that are expected to be especially relevant to achieve high performance from analog charge cloud reconstruction.

Abstract: A system and method for a multi-sensor pixel architecture for use in a digital imaging system is described. The system includes at least one semiconducting layer for absorbing radiation incident on opposites of the at least one semiconducting layer along with a set of electrodes on one side of the semiconducting layer for transmitting a signal associated with the radiation absorbed by the semiconducting layer.

Abstract: A radiation detector may include a scintillator, a light source, and a sensor. The scintillator may include various scintillation materials capable of converting non-visible radiation (incoming radiation) into visible light. The sensor may be placed in adjacent or in close proximity to the scintillator, such that any converted visible light may be detected or measured by the sensor. The light source may be placed in adjacent or in close proximity to the scintillator, such that light from the light source may interact with defects in the scintillator to minimize interference on the conversion of non-visible radiation into visible light caused by the defects.

Abstract: A radiation imaging device includes a radiation source and a micro structured detector comprising a material defining a surface that faces the radiation source. The material includes a plurality of discreet cavities having openings in the surface. The detector also includes a plurality of quantum dots disclosed in the cavities. The quantum dots are configured to interact with radiation from the radiation source, and to emit visible photons that indicate the presence of radiation. A digital camera and optics may be used to capture images formed by the detector in response to exposure to radiation.

Abstract: A color filter array, a method of manufacturing the same, and an image sensor including the same are provided. The color filter array includes: a color filter arrangement including a plurality of color filters on a substrate; and an isolation wall which isolates each of the color filters and includes a solid including a plurality of air spaces.

Abstract: A computed tomography (CT) image apparatus includes a plurality of photon-counting detectors (PCD); and processing circuitry configured to obtain a photon count of a PCD of the plurality of PCDs, compare the obtained photon count to a predetermined photon-count threshold, and apply an external light source to the PCD when the obtained photon count is larger than the predetermined photon-count threshold.

Abstract: The invention relates to a radiation detector (100) and an associated method for the detection of (e.g. X or ?-) radiation. The detector (100) comprises a converter element (110) in which incident photons (X) are converted into electrical signals, and an array of anodes (130) for generating an electrical field (E) in the converter element (110). At least two anodes are associated with two steering electrodes (140) to which different potentials can be applied by a control unit (150). Preferably, each single anode or small group of anodes is surrounded by one steering electrode. The potentials of the steering electrodes (140) may be set as a function of the potentials that are induced in these electrodes when an operating voltage is applied between the anodes and a cathode (120). Moreover, a grid electrode (160) may be provided that at least partially encircles anodes (130) and their steering electrodes (140).

Abstract: An X-ray article and method for analyzing hard X-rays which have interacted with a test system. The X-ray article is operative to diffract or otherwise process X-rays from an input X-ray beam which have interacted with the test system and at the same time provide an electrical circuit adapted to collect photoelectrons emitted from an X-ray optical element of the X-ray article to analyze features of the test system.

Abstract: A shield has a detector installing hole having a central axis orthogonal to a central axis of a detection tube. A radiation sensor of a columnar scintillation detector to which a low concentration side measurement range within all required measurement ranges is allocated is arranged inside the detector installing hole. An ionization chamber to which a high concentration side measurement range is allocated is arranged side by side in parallel with the detection tube. The measurement range of the columnar scintillation detector and the measurement range of the ionization chamber are adjusted so as to be overlapped with each other.

Abstract: The present disclosure is directed to a system and method for performing out-of-order message filtering with aging. The system and method can be used in a destination device that can receive messages out-of-order (i.e., in a different order than they were transmitted) from a source device. The system and method can filter-out or flag for appropriate handling these messages received out-of-order. To perform the above noted message filtering functionality, the system and method uses a database constructed from a content-addressable memory (CAM) and a random-access memory (RAM) to respectively remember source identifiers and sequence identifiers associated with previously received messages. A source identifier identifies the source of a message, and a sequence identifier identifies the transmission order of the message among the messages transmitted from the particular source. Each message can include a source identifier and a corresponding sequence identifier.

Abstract: Described is a radiation dosimeter including multiple sensor devices (including one or more passive integrating electronic radiation sensor, a MEMS accelerometers, a wireless transmitters and, optionally, a GPS, a thermistor, or other chemical, biological or EMF sensors) and a computer program for the simultaneous detection and wireless transmission of ionizing radiation, motion and global position for use in occupational and environmental dosimetry. The described dosimeter utilizes new processes and algorithms to create a self-contained, passive, integrating dosimeter.

Abstract: A detector array includes at least one direct conversion detector pixel (114-114M) configured to detect photons of poly-chromatic ionizing radiation. The pixel includes a cathode layer (116), an anode layer (118) including an anode electrode (118-118 M ) for each of the at least one detector pixels, a direct conversion material (120), disposed between the cathode layer and the anode layer, and a gate electrode disposed in the direct conversion material, parallelto and between the cathode and anode layers.

Abstract: An x-ray transmission device includes two surfaces in frictional contact within a low fluid pressure environment provided by a housing substantially opaque to x-rays. Materials of the two surfaces are selected such that the frictional contact generates relative charging between the surfaces. The housing includes a window substantially transparent to x-rays, and an electron target, for example a metal, is on an interior surface of the window. The electron target faces the surface that is relatively negatively charged, such that electrons accelerated from that surface, or accelerated due to the negative charge of that surface strike the electron target to generate x-rays, which may be transmitted through the window.

Abstract: A wireless radiation system that includes: a generator including a first wireless communication module; and a radiation detector including a digital screen and a second wireless communication module. The radiation detector is configured to display a captured radiation image on the digital screen and to transmit the captured radiation image, using the second wireless communication module, to a server. The first and second wireless communication modules are configured to wirelessly synchronize a radiation generation by the radiation generator and an exposure to the radiation by the radiation detector.

Abstract: A focal plane array having: a plurality of detectors; a plurality of unit cell sections, each section being fed by charge produced by corresponding detector for producing a sequence of frames; and a plurality of sets of storage sections, each section being coupled to a corresponding one of the unit cells. Each set of storage sections includes a plurality of storage units for sequentially storing the frames. A region of interest selector section examines the frames of the plurality of unit cells, to detect at least one of the frames having a predetermined characteristic. A processor: (i) identifies a sub-set of the plurality of unit cells proximate the detected unit cells having the predetermined characteristic to establish a region of interest; and (ii) sequentially reads the plurality of storage units in the storage sections coupled to the sub-set of unit cells in the established region of interest.

Abstract: The invention relates to a radiation detector (100) comprising a scintillator group with for example two scintillator elements (120a, 120b) for converting incident primary photons (X, X?) into secondary photons (?, ??) according to a characteristic emission spectrum. Moreover, the detector comprises at least two photodetectors (130a, 130b) for converting said secondary photons into electrical signals, wherein said photodetectors have different absorption spectra and can be read out separately. According to a preferred embodiment of the invention, the photodetectors are organic photodetectors (130a, 130b). The scintillator elements (120a, 120b) and the photodetectors are preferably arranged in a stack one behind the other. Due to the at least two photodetectors (130a, 130b), additional information about incident primary radiation (X, X?) can be collected.

Abstract: A dynamic diagnosis support information generation system includes: a radiation generator capable of irradiating a pulsed radiation; a radiation detector which is provided with a plurality of detecting elements arranged in two-dimension, detects the pulsed radiation irradiated from the radiation generator at each of the plurality of detecting elements and generates frame images successively; and an analysis section which calculates and outputs a feature value relating to a dynamic image of a subject based on a plurality of frame images generated by radiographing the subject by using the radiation generator and the radiation detector, wherein the analysis section calculates the feature value relating to the dynamic image of the subject by corresponding pixels to each others representing outputs of a detecting element at a same position in the radiation detector among the plurality of the frame images.

Abstract: Integrated circuits and methods for deactivating user circuit operation with one or more wide channel sensing transistors biased to an on condition for exposure to total ionizing dose and then to an off condition for measurement and comparison of a leakage current or threshold voltage parameter to a predetermined reference, and a deactivation circuit selectively disables operation of the user circuit if the sensed parameter is greater than or equal to the reference.

Abstract: A small anode germanium well (SAGe well) radiation detector system/method providing for low capacitance, short signal leads, small area bottom-oriented signal contacts, enhanced performance independent of well diameter, and ability to determine radiation directionality is disclosed. The system incorporates a P-type bulk germanium volume (PGEV) having an internal well cavity void (IWCV). The external PGEV and IWCV surfaces incorporate an N+ electrode except for the PGEV external base region (EBR) in which a P+ contact electrode is fabricated within an isolation region. The PGEV structure is further encapsulated to permit operation at cryogenic temperatures. Electrical connection to the SAGe well is accomplished by bonding or mechanical contacting to the P+ contact electrode and the N+ electrode. The EBR of the PGEV may incorporate an integrated preamplifier inside the vacuum housing to minimize the noise and gain change due to ambient temperature variation.

Abstract: The present disclosure provides a High-Purity Germanium (HPGe) detector, comprising: a HPGe single crystal having an intrinsic region exposed surface; a first electrode and a second electrode connected to a first contact electrode and a second contact electrode of the HPGe single crystal respectively; and a conductive guard ring arranged in the intrinsic region exposed surface around the first electrode to separate the intrinsic region exposed surface into an inner region and an outer region. A leakage current derived from the intrinsic region exposed surface of the HPGe detector can be separated from the current of the HPGe detector by the conductive guard ring provided in the surface, thereby suppressing the interference of the surface leakage current.