110 results about "Pixel detector" patented technology

The invention discloses a special environment laser radar system and method based on polarization modulation and laser coding. The laser radar system comprises a polarization modulation laser emitting unit, a multi-channel receiving unit and a compressed sensing reconstruction unit. The polarization modulation laser emission unit comprises a laser, a beam expanding module, a spatial light modulator, a micro galvanometer array, a spatial filter and a first focusing lens which are arranged in sequence; the multi-channel receiving unit comprises a second focusing lens, a polarization beam splitter and a single-pixel detector array which are arranged in sequence; and the compressed sensing reconstruction unit comprises a compressed sensing processing module, an image reconstruction module and a loop adaptive control module which are arranged in sequence. The anti-interference capability in a complex environment is enhanced through polarization modulation, the detection resolution and the signal-to-noise ratio are improved in combination with laser coding, the imaging quality and stability of the laser radar in a special environment are greatly improved, and the method can be widely applied to the fields of military reconnaissance, disaster rescue, unmanned driving and the like.

The invention provides a single-pixel detection device with a flexible and variable measurement view field, and an optical detection system and method. The single-pixel detection device comprises a view field diaphragm, a focusing lens and a single-pixel detector, the view field diaphragm is arranged in a detection light path of the measured target, is a view field diaphragm with a flexible and variable measurement view field, can automatically adjust the shape of the measurement view field according to the shape of the measured target, obtains the measurement view field completely matched with the shape of the measured target, and outputs an output light beam with the same shape as the measured target; and the focusing lens is arranged in an output light path of the field diaphragm and is used for focusing an output light beam of the field diaphragm to the single-pixel detector, so that the single-pixel detector detects a signal of the detected target. According to the single-pixel detection device with the flexible and variable measurement view field and the optical detection system provided by the invention, the view field diaphragm is introduced into the detection light path, and the measurement view field of the view field diaphragm can be flexibly adjusted, so that flexible, simple and accurate single-pixel detection on measured targets with different shapes in optical detection is realized.

The invention discloses a pulse terahertz time-domain spectroscopy system of a single photoconductive antenna and a detection method, and relates to the technical field of terahertz, the system comprises a laser pulse generation module, a single photoconductive antenna module, a compression sampling module, a signal reconstruction module and a control unit; by integrating the random light delay modulation unit and the single-pixel detector, the system realizes random time interval sampling of terahertz signals, effectively breaks through the limitation of a traditional sampling mode, improves the flexibility and efficiency of signal acquisition, and combines a signal reconstruction module of an FPGA + GPU heterogeneous computing architecture, so that the system has a wide application prospect. The system can adaptively construct a sparse base and perform accurate sparse representation on a measurement vector, so that an original terahertz time domain signal is efficiently reconstructed by optimizing a target function and an adaptive iterative solution algorithm, the signal reconstruction precision is improved, the data processing complexity is also reduced, and the method is suitable for large-scale popularization and application. And powerful support is provided for practical application of the terahertz technology.

A spectrometer for detecting an electromagnetic (EM) wave spectrum having one or more wavelength components within a spectral band of interest, a method of detecting an electromagnetic (EM) wave spectrum having one or more wavelength components within a spectral band of interest, and a method of constructing the spectrometer. The method comprises the steps of creating dispersed images of an entrance aperture on a plane of an exit aperture, such that respective images at the different wavelength components are offset by different amounts of displacements along a direction of dispersion; gathering a first EM wave energy incident on the entrance aperture to an EM detector; gathering a second EM wave energy that exits the exit aperture to the at least one single-pixel detector; and measuring the output of the EM detector and the output of the at least one single pixel detector for reconstructing the EM wave spectrum taking into account an intensity distribution of an incident EM wave on the entrance aperture.

A spectral sensing device and associated methods for enhanced diagnostic capabilities across medical fields are disclosed. The device incorporates multispectral, hyperspectral, and photoplethysmography technologies to analyze biological features including tongue, oral cavity, saliva, teeth, and other tissues. The system transforms any standard RGB camera into a multispectral imaging device by training machine learning models to associate RGB values with spectral values inside and outside the visible spectrum using measurements from a single pixel detector spectroradiometer. A multimodal neural network with separate processing branches analyzes spectral images, non-spectral images, and tabular data to predict microbiome composition. The system generates health risk assessments by comparing predicted microbial abundances to thresholds associated with various medical conditions. Near-infrared sensing enables blood flow monitoring, subcutaneous imaging, and assessment of physiological parameters. Convolutional neural networks enable spectral reconstruction without requiring the physical device, while supporting continuous monitoring in various form factors.

The invention relates to the technical field of X-ray imaging, and provides a novel dual-energy detector and scanning equipment. The novel dual-energy detector comprises a plurality of first pixel detector assemblies, a second pixel detector assembly and a filtering assembly, the first pixel detector assembly, the filtering assembly and the second pixel detector assembly are sequentially arranged in the X-ray propagation direction, the pixel size of the first pixel detector assembly is smaller than that of the second pixel detector assembly, the first pixel detector assembly is used for receiving low-energy X-rays, and the filtering assembly is used for filtering the low-energy X-rays. And the second pixel detector assembly is used for receiving the high-energy X-rays filtered by the filtering assembly. The pixel size of the first pixel detector assembly is set to be smaller than the pixel size of the second pixel detector assembly, so that the imaging penetration rate can be improved.

The invention belongs to the technical field of imaging, and particularly relates to a single-pixel imaging reconstruction method and device based on compressed sensing. The core of the method is to construct an FRSPINet network architecture based on deep learning. The method comprises the following steps: firstly, constructing a cascade network model composed of a data preprocessing module, a deep separable convolution module, a full connection module, a shallow feature extraction module, an attention mechanism module and an image reconstruction module; carrying out gradient optimization on network parameters through multi-stage iterative training, dynamically adjusting a learning rate based on convergence of an SSIM loss function, and storing optimal weight parameters; in an imaging stage, a compression measurement value of a target scene is obtained through a single-pixel detector in a preset sampling mode, and after the compression measurement value is transmitted to a computing terminal through a data acquisition card, the compression measurement value is input into a pre-trained FRSPINet network for end-to-end nonlinear mapping, and finally a high-fidelity reconstructed image is output. And the image reconstruction quality and the system robustness at a low sampling rate are effectively improved.

A radiation detector unit including an interposer configured to electrically connect a pixelated radiation sensor positioned on a front side of the interposer to an application-specific integrated circuit (ASIC) positioned on a back side of the interposer, where the interposer has at least one feature which equalizes the energy resolution (ER) response of edge and center pixel detectors of the pixelated radiation sensor within 10% of one another.

The invention discloses a correlated imaging impurity detection method and system for drug production, and relates to the technical field of drug impurity detection. The method comprises the following steps: loading a first binary mask matrix, projecting a target product area, controlling a single-pixel detector to detect, determining a first measurement value, and performing lightweight reconstruction to obtain a first preview; generating a second binary mask matrix and performing projection and detection reconstruction by pre-checking the first preview, and performing multi-round iteration until an Nth preview is determined; calling the first preview to the Nth preview from a temporary database of an online detection platform, executing multi-layer compressed sensing and reconstruction, and determining a reconstruction result; and aiming at a reconstruction result, matching in an impurity feature library, and determining an impurity verification result. The technical problems of low impurity detection efficiency and insufficient detection accuracy in the medicine production process in the prior art are solved, and the technical effect of efficient and accurate online detection of medicine impurities in the production link is achieved.

The invention discloses a DMD dynamic area activation three-dimensional imaging system based on camera visual positioning, and relates to the technical field of optics. Aiming at the problems of low activation efficiency, poor light spot adaptability and insufficient dynamic scene adaptation of an existing system DMD full panel, the position and the size of a laser light spot on a DMD panel are captured in real time through camera visual positioning, a micro-mirror area just surrounding the light spot is dynamically activated through image preprocessing, boundary extraction and coordinate mapping, and the laser light spot is accurately activated. A matched measurement matrix is generated according to the size of the activation area and is loaded to the DMD to realize spatial coded modulation, a single-pixel detector synchronously acquires modulation signals, a phase difference is calculated in combination with a four-step phase shift method, and a three-dimensional depth map is reconstructed. According to the method, DMD full panel activation is not needed, the micromirror utilization rate and imaging efficiency are remarkably improved, meanwhile, the three-dimensional imaging precision is guaranteed, and the method is suitable for industrial part detection, small and medium-sized target modeling and other scenes.

The invention relates to a three-dimensional semiconductor pixel detector and a manufacturing method thereof. A pre-prepared array carrier provided with a plurality of detection cavities arranged in an array is obtained, the inner surfaces of the detection cavities are provided with conductive layers, each detection cavity is internally provided with a central electrode of a detection pixel, the central electrodes are not in contact with the inner surfaces of the detection cavities, and the conductive layers are used as surface electrodes of the detection pixels; preparing a detection medium of a detection pixel in each detection cavity of the array carrier by adopting a preset low-temperature growth mode to obtain a three-dimensional semiconductor pixel detector comprising the array carrier and the detection pixel in each detection cavity; a detection medium in the detection cavity is located between the central electrode and the conductive layer; in each detection cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium. And the collection time of carriers can be greatly shortened, so that the saturation counting rate, the energy resolution and other performances are improved, the process is simple, the cost is low, and the applicable material range is wider.

The invention provides a radio frequency marking axial single-time rapid imaging device and method. The radio frequency marking axial single-time rapid imaging device comprises a detection light source, a radio frequency marking unit and a sample axial excitation detection unit, the radio frequency marking unit carries out radio frequency marking on each spectral component in the detection light beam emitted by the detection light source to obtain the detection light beam after radio frequency marking; the sample axial excitation detection unit comprises an objective lens and a single-pixel detector, the objective lens adopts a dispersion objective lens, each modulated spectral component in the detection light beam after radio frequency marking is focused to different depths in the axial direction of the sample, and signal light generated at each depth is simultaneously detected by the single-pixel detector at a time. According to the radio frequency mark axial single-time fast imaging device and method, fast axial imaging can be achieved within a large depth range, and meanwhile axial random fast imaging is achieved.

The application discloses a multi-band infrared polarization selection photoelectric detection array and a preparation method thereof in the field of photoelectric devices, and the photoelectric detection array comprises a transparent insulating substrate, and array-distributed internal unit pixel detectors are arranged above the transparent insulating substrate, wherein the internal unit pixel detectors comprise a gate electrode, an insulating layer, an active layer, a source-drain electrode and a photosensitive layer, the gate electrode is arranged above the transparent insulating substrate, the gate electrode is covered with the insulating layer, the active layer is arranged above the insulating layer, and the photosensitive layer and the source-drain electrode are arranged above the active layer. The photoelectric detection array can be combined with a polarimetry instrument and a chemical analysis platform device in aspects such as component identification and concentration detection of a liquid solution; the design and preparation of the field effect transistor photoelectric polarization selection device can simultaneously cancel a polaroid, realize integration of polarization angle detection and wavelength absorption detection, and can monitor the component and the concentration of the solution in a characteristic waveband of the solution.

The invention belongs to the technical field of object imaging, and particularly relates to an imaging method of a rotating object. The imaging method comprises the following steps that a rotating picture with the duration T of an imaging target is intercepted, the rotating picture is equally divided into a plurality of equal time periods according to the time interval delta t, and the duration T is larger than the duration of one circle of rotation of the imaging target; imaging the picture in each time period by adopting a plurality of different modulation signals, and acquiring an intensity value of reflected light through a single-pixel detector; calculating a one-dimensional projection curve of the imaging target in each time period according to the intensity value and the modulation signal; arranging the one-dimensional projection curves in different time periods according to time to obtain a projection curve time change diagram of the imaging target; and establishing an angle projection curve according to the time interval delta t, the rotation speed of the imaging target and the projection curve time change diagram, and performing back projection to realize imaging of the rotation target. According to the invention, the rotating object can be effectively imaged.

The invention discloses a single-pixel non-vision-field imaging system and a super-resolution reconstruction method thereof, belongs to the field of optical systems, and aims to solve the problems in the prior art. The system comprises a light source, a DMD (Digital Micromirror Device), a plane mirror, a plano-concave lens, an object to be measured, a shielding object, a plano-convex lens, a plane mirror, a single-pixel detector, a data collector and a computer; the DMD, the plane mirror, the plano-concave lens, the plano-convex lens, the plane mirror and the single-pixel detector are coaxially arranged; light beams emitted by the light source are modulated by the DMD, illumination speckles preset by a computer are projected, the speckles are reflected to the plano-concave lens through the plane mirror and then irradiate the surface of an object to be measured through the plano-concave lens, and transmitted light is converged by the plano-convex lens after being reflected by the shielding object, then reflected by the plane mirror and finally captured by the single-pixel detector. The single-pixel detector transmits collected data to the data collector, the data collector transmits the data to the computer for processing, and finally a target image is reconstructed.

The invention relates to the technical field of terahertz wave single-pixel imaging, and discloses a real-time terahertz wave single-pixel imaging method, device and system and computer equipment, and the method comprises the steps: obtaining a terahertz wave single-pixel measurement value of a to-be-imaged object; the terahertz wave single-pixel measurement value is a one-dimensional signal obtained by measuring an object to be imaged through a terahertz wave single-pixel detector; and inputting the terahertz wave single-pixel measurement value into a pre-constructed image reconstruction model to obtain a terahertz wave reconstruction image of the object to be imaged. Through the deep neural network model based on physical guidance, the reconstruction quality and reconstruction time of the terahertz wave image under the under-sampling condition can be effectively improved, and through the real-time terahertz wave single-pixel imaging device with a high-speed switch, the relation between the imaging speed and the imaging quality is effectively balanced, and the imaging quality is improved. And the reconstruction efficiency of real-time terahertz wave single-pixel imaging is further improved.

The application discloses a peak holding circuit of a pixel detector with adaptive matching leakage current function and relates to the field of semiconductor integrated circuits. The peak holding circuit is used to solve the problem that the voltage signal holding time is affected due to the limitation of the capacitor in the peak holding circuit. The positive input end of a voltage comparator is connected with the signal input end of the peak holding circuit, the reverse input end of the voltage comparator is connected with the voltage output end of a holding core circuit, the output end of the voltage comparator is connected with the current source control end of the holding core circuit, and the voltage output end of the holding core circuit is connected with the voltage input end of an adaptive leakage current matching circuit. When the positive input signal of the voltage comparator is greater than or equal to the reverse input signal, the holding core circuit adjusts the voltage value output from the output end to increase. When the positive input signal of the voltage comparator is less than the reverse input signal, the holding core circuit adjusts the voltage value output from the output end to remain stable, and the adaptive leakage current matching circuit adaptively matches the leakage of the output voltage of the holding core circuit.

The utility model discloses a kind of heat dissipation package structures of pixel detector chip module, it is related to heat dissipation packaging technical field, including DBC substrate and heat dissipation module;The pixel detector chip module includes adaptively connected pixel type detection sensor, connector and multiple processor chips, wherein, the pixel type detection sensor is set to DBC substrate front, the connector and multiple processor chips are set to DBC substrate back;The front of the heat dissipation module is provided with first boss, second boss and multiple bumps between first boss and second boss, and the back of DBC substrate is connected by first boss, second boss and multiple bumps with the heat dissipation module.The heat dissipation package structure has good heat dissipation capacity, and can better meet the heat dissipation demand when pixel type detector module works.

The application provides a single-pixel diffraction imaging method and device, and belongs to the field of coherent diffraction imaging and computational photography, wherein the method comprises the following steps: (1) in the single-pixel imaging light path, different modulation sequences are used to modulate the illumination light beam of the target scene, and a single-pixel detector is used to record the intensity value of a one-dimensional sequence; (2) the intensity value corresponding to the different modulation sequences is used to replace the amplitude value of the reconstructed diffraction light field on the detector plane, and then alternating iteration calculation is performed until the target scene is reconstructed. The application has the advantages of simple structure, strong operability, wide application range and strong expandability. Through the application, the cost of single-pixel diffraction imaging can be reduced, fast and accurate measurement of the target scene is realized, and convenience is brought to high-quality single-pixel imaging.

The invention belongs to the technical field of mid-infrared imaging, and discloses a mid-infrared two-photon calculation imaging system and method based on pumping space coding, and the method comprises the steps: carrying out the spatial intensity coding of near-infrared pumping light through employing a spatial light modulator; the intensity code of the pump light is mapped into the non-degenerate light by means of the nonlinear effect of the single-pixel detector, the detector outputs the integral intensity value of the non-degenerate signal related to the spatial intensity code, and the two-dimensional information of the object to be detected is reconstructed by combining the correlation algorithm. By means of the non-degenerate two-photon absorption effect of a single-pixel detector material, structural detection of a mid-infrared light field is achieved. Compared with direct modulation in a mid-infrared light field, the method has the advantages that the influence caused by a long-wave diffraction effect is effectively avoided, high-precision coding modulation is realized, and the physical pixel limitation of a traditional mid-infrared detector is effectively broken through. The invention has the technical advantages of high imaging sensitivity, fast time response, high modulation precision, large imaging field of view, wide response band and the like.

The invention provides a single-pixel imaging-free moving target positioning method, which comprises the following steps: S1, constructing a Gaussian mixture background model to detect a moving target and a background; s2, irradiating the digital micromirror device through a light source, and projecting the initial template pattern to the surface of a target scene; receiving the light beam reflected by the target to a single-pixel detector; s3, constructing a Kalman filtering prediction model, and predicting the position area of the target in the next frame; s4, dynamically matching the template in the prediction area, calculating SSIM values, positioning a position corresponding to the maximum SSIM value, and marking a target in a rectangular frame, namely a positioning result; and S5, updating the region corresponding to the maximum SSIM value into a new template, iteratively updating the Kalman filtering state, and realizing continuous tracking until the maximum frame number is reached. The method does not need a complex optical system and imaging equipment, reduces the system complexity, does not generate an image, and is suitable for a scene needing privacy protection.

The embodiment of the present application provides an imaging method and system. The imaging method comprises the following steps: using pseudo-thermal light as probe light, and irradiating the probe light to a moving object to form reflected light; receiving the reflected light by using a single-pixel detector, and determining a Doppler frequency shift distribution of the reflected light relative to the probe light by using a frequency analysis system; obtaining a velocity sequence of the moving object based on the Doppler frequency shift distribution of the reflected light relative to the probe light; and constructing a full-view velocity image and a spatial image of the moving object by using a pre-stored reference spatial thermal light field distribution and the velocity sequence based on a correlation imaging algorithm, wherein the spatial image corresponds to a reflectivity distribution of the moving object, the direction of the velocity of the moving object is perpendicular to the plane where the collection surface of the single-pixel detector is located, and the velocity sequence corresponds to the pre-stored reference spatial thermal light field distribution.

An example includes a method for producing a multipixel detector, the method including: providing a bottom layer including a first and a second bottom electrode, depositing an electrically insulating layer on the bottom layer, forming a first opening through the electrically insulating layer, depositing a first photon absorbing material in the first opening, forming a second opening through the electrically insulating layer, depositing a second photon absorbing material in the second opening, planarizing the deposited electrically insulating layer, the first photon absorbing material, and the second photon absorbing material to form a flat surface, and forming a common top electrode on top of the flat surface.

The present invention relates to the field of plasma physics nuclear detection technology, and in particular provides a short-pulse X-ray source polarization measuring instrument and a polarization measuring method. The measuring method includes: the incident X-ray falls on a scatterer through a collimation component to generate scattered photons, and the scattered photon signals are detected by a semiconductor pixel detector; the measured value E1 of the energy of the scattered photons is obtained by using the semiconductor pixel detector, and the energy E0 of the X-ray photons is calculated based on the measured value E1; the pixel position of the scattered photons is obtained by using the semiconductor pixel detector; based on the pixel position of the scattered photons, the polarization direction and polarization degree of the X-ray are obtained by data fitting. The purpose is to solve the problem that the existing polarization measuring instrument cannot quickly measure the polarization degree and realize the measurement of the energy of the incident X-ray without knowing the polarization direction of the X-ray, and realize the single-shot measurement function of the polarization degree and energy spectrum of the short-pulse X-ray source.

The application discloses a single light guide antenna pulse terahertz time-domain spectroscopy system and a detection method, and relates to the technical field of terahertz. The system comprises a laser pulse generation module, a single light guide antenna module, a compressed sampling module, a signal reconstruction module and a control unit. The application integrates a random light delay modulation unit and a single-pixel detector, realizes random time interval sampling of a terahertz signal, effectively breaks through the limitation of a traditional sampling mode, improves the flexibility and efficiency of signal acquisition, and combines a signal reconstruction module of an FPGA+GPU heterogeneous computing architecture. The system can adaptively construct a sparse base, accurately sparsely represent a measurement vector, and then efficiently reconstruct an original terahertz time-domain signal through an optimization objective function and an adaptive iterative solution algorithm. The application not only improves the accuracy of signal reconstruction, but also reduces the complexity of data processing, and provides strong support for the practical application of terahertz technology.

This application discloses a pixel detector. Each pixel unit includes a local discrimination module that acquires a center pixel signal and compares it with a set local threshold for the center pixel to obtain a local discrimination signal for the center pixel; a global discrimination module that acquires a global discrimination signal for the center pixel; an arbitration module that determines whether the center pixel needs to be counted based on the above signals; and a counting module that increments the count by one when it needs to be counted, based on the result of the arbitration module. According to the technical solution provided by the embodiments of this application, by designing the pixel interconnection logic as a five-pixel interconnection, the counting judgment of the center pixel only needs to be performed through the other four pixels surrounding the center pixel, providing a simpler and more efficient implementation scheme.

The invention provides a single-pixel imaging method and system based on an array light source coherent synthesis vortex light field, and the method comprises the steps: enabling a single path of laser to pass through a collimation beam expander, then carrying out the amplification, enabling the amplified laser to pass through a circular-ring-shaped arrangement mask plate to form an array light source, and then carrying out the emission and output; specific phases are loaded to different sub-apertures of the array light source through the spatial light phase modulator so as to realize light field modulation; performing far-field coherent synthesis to obtain a vortex light field with specific intensity distribution, and after the vortex light field irradiates a target object, recording a return light intensity detection value by a single-pixel detector; and obtaining a target object image based on the vortex light field intensity distribution and the return light intensity detection value in combination with a single-pixel imaging reconstruction algorithm. Compared with the prior art, the method has the advantages of being high in sampling speed, high in imaging quality, good in noise robustness and the like, and is expected to be widely applied to the field of long-distance target detection imaging.

The present invention relates to a bionic multispectral polarization single-pixel imaging device and method based on a neural overlapping compound eye. The device comprises: a substrate; multiple sub-eyes; the multiple sub-eyes are evenly distributed on the substrate, each sub-eye being composed of at least one optical fiber; at least one set of imaging channels, the front end of each set of imaging channels being composed of optical fibers located in the same position in each sub-eye, and the rear end being composed of optical fibers located in the same position in each sub-eye fixed together; at least one filter or polarizer located at the rear end of the imaging channel; and at least one single-pixel detector located behind each filter or polarizer. The imaging device provided by the present invention has a compact structure, small footprint, low production cost, a large imaging field of view, a high imaging dynamic range, and high target recognition efficiency.

The invention discloses a laminated pixel detector with an expanded dynamic range. The laminated pixel detector comprises a pixel array, and each pixel in the pixel array comprises a sensor and a reading circuit; the reading circuit is characterized in that the integrating capacitor of each reading circuit is arranged on an external substrate to form an external capacitor array sheet which is used for storing photoelectrons generated by each sensor. According to the invention, each pixel of the pixel detector is connected with the external capacitor array sheet, photoelectrons generated by the sensor are stored in the external capacitor array sheet, and the purpose of expanding the pixel input dynamic range is achieved; compared with a traditional pixel detector, the integral capacitor is not limited by the pixel size of the reading circuit, integral reading of more photoelectrons can be achieved, and therefore a larger input dynamic range is achieved.

A spectrometer for detecting electromagnetic (EM) spectra having one or more wavelength components within a spectral band of interest, and a method for detecting electromagnetic (EM) spectra having one or more wavelength components within a spectral band of interest. The method utilizes an entrance aperture; a dispersive and imaging optics comprising at least one dispersive element; an exit aperture; a collection optics; and at least one single-pixel detector, each single-pixel detector being sensitive to one or more wavelength components. The method includes the following steps: spatially encoding at least one entrance slit of an entrance aperture in a direction generally transverse to the dispersion direction of the dispersive and imaging optics; creating a dispersive image of the entrance aperture on the plane of the exit aperture using the dispersive and imaging optics, such that the images of different wavelength components are offset by different amounts of displacement along the dispersion direction; spatially encoding a plurality of exit slits of the exit aperture in a direction generally transverse to the dispersion direction, wherein the exit aperture includes a plurality of exit slits arranged along the dispersion direction; collecting the total electromagnetic energy entering and leaving the entrance aperture to at least one of at least one single-pixel detectors using a collection optics; repeatedly changing at least one of the encoding patterns of the at least one entrance slit and the encoding patterns of the plurality of exit slits; and measuring the output of at least one detector for a corresponding number of times the electromagnetic spectrum is reconstructed.