Showing papers on "Zone plate published in 2022"

Terahertz metasurface zone plates with arbitrary polarizations to a fixed polarization conversion

Abstract: Metasurfaces that can realize the polarization manipulation of electromagnetic waves on the sub-wavelength scale have become an emerging research field. Here, a novel strategy of combining the metasurface and Fresnel zone plate to form a metasurface zone plate is proposed to realize the conversion from nearly arbitrary polarizations to a fixed polarization. Specifically, when one polarized wave is incident on adjacent ring zones constructed by different types of meta-atoms, the transmitted waves generated by odd-numbered and even-numbered ring zones converge at the same focus and su-perimpose to generate a fixed polarized wave. As function demonstrations, we have designed two types of metasurface zone plates: one is a focused linear polarizer, and the other can convert nearly arbitrary polarized waves into focused circularly polarized waves. The simulated and measured results are consistent with theoretical expectations, suggesting that the proposed concept is flexible and feasible. Our work provides an alternative platform for polarization manipulation and may vigorously promote the development of polarization photonic devices. Terahertz metasurface zone plates with arbitrary polarizations to a fixed polarization conversion. Opto-Electron Sci 1 , 210014 (2022).

An achromatic X-ray lens

Abstract: Diffractive and refractive optical elements have become an integral part of most high-resolution X-ray microscopes. However, they suffer from inherent chromatic aberration. This has to date restricted their use to narrow-bandwidth radiation, essentially limiting such high-resolution X-ray microscopes to high-brightness synchrotron sources. Similar to visible light optics, one way to tackle chromatic aberration is by combining a focusing and a defocusing optic with different dispersive powers. Here, we present the first successful experimental realisation of an X-ray achromat, consisting of a focusing diffractive Fresnel zone plate (FZP) and a defocusing refractive lens (RL). Using scanning transmission X-ray microscopy (STXM) and ptychography, we demonstrate sub-micrometre achromatic focusing over a wide energy range without any focal adjustment. This type of X-ray achromat will overcome previous limitations set by the chromatic aberration of diffractive and refractive optics and paves the way for new applications in spectroscopy and microscopy at broadband X-ray tube sources.

Chromatic confocal measurement method using a phase Fresnel zone plate.

Abstract: A chromatic confocal measurement method based on a phase Fresnel zone plate (FZP) is described. Strong dispersion of FZP results in significant axial focal shift. The axial dispersion curve is close to linear within a certain wavelength range determined by the quantitative calculation using the vectorial angular spectrum theory. A 11.27 mm diameter phase FZP with a primary focal length of 50 mm was processed using standard photolithography technology and used as the dispersive objective in a homemade chromatic confocal measurement system. The calibrated axial measurement range exceeds 16 mm, the axial resolution reaches 0.8 µm, and the measurement accuracy of displacement is better than 0.4%. This chromatic confocal sensor has been practically used in the measurement of step height, glass thickness, and 3D surface profile. The proposed method has the obvious characteristics of simplicity, greatly reduced cost and superior performance. It is believed that this sensing method has broad application prospects in glass, coating, machinery, electronics, optics and other industries.

An achromatic X-ray lens

Abstract: Diffractive and refractive optical elements have become an integral part of most high-resolution X-ray microscopes. However, they suffer from inherent chromatic aberration. This has to date restricted their use to narrow-bandwidth radiation, essentially limiting such high-resolution X-ray microscopes to high-brightness synchrotron sources. Similar to visible light optics, one way to tackle chromatic aberration is by combining a focusing and a defocusing optic with different dispersive powers. Here, we present the first successful experimental realisation of an X-ray achromat, consisting of a focusing diffractive Fresnel zone plate (FZP) and a defocusing refractive lens (RL). Using scanning transmission X-ray microscopy (STXM) and ptychography, we demonstrate sub-micrometre achromatic focusing over a wide energy range without any focal adjustment. This type of X-ray achromat will overcome previous limitations set by the chromatic aberration of diffractive and refractive optics and paves the way for new applications in spectroscopy and microscopy at broadband X-ray tube sources.

Sector-based Fresnel zone plate with extended depth of focus

Abstract: • A sector-based Fresnel Zone Plate with Extended Depth of Focus is proposed. • Easy to manufacture since the proposed Fresnel Zone plate is binary. • Potential applications in many technological areas. • An increasing of the Depth of Focus almost 7 times with less than double width of focus is obtained. A Sector-based Fresnel zone plate consists of a binary diffractive lens composed of a mosaic of sectors of Fresnel zone plates with different focal distances. When these focal distances are linearly distributed within the sectors, dual focus is obtained. Besides, we explore the possibility to generate an extended depth-of-focus lens by using a cubic distribution of the focal distances assigned to the sectors and optimizing the weight factors given to the terms of the cubic polynomial. Finally, numerical simulations based on the Rayleigh-Sommerfeld approach are carried out and experimental verifications by using a Spatial Light Modulator are performed, showing high agreement. The proposed kind of zone plate has potential applications in different research fields such as microscopy, lithography, data storage, or imaging.

Generation of a focused optical vortex beam using a liquid crystal spiral zone plate

Abstract: Optical vortices (OVs) with orbital angular momenta show promise for various optical applications. Spiral zone plates (SZPs) can generate a focused OV and are thus used in applications like edge-enhanced imaging. However, conventional SZPs have low diffraction efficiency because they operate based on amplitude modulation. This study proposes a liquid crystal spiral zone plate (LCSZP) that operates based on phase modulation and demonstrates the generation of a focused OV with high efficiency and electric tunability. The LCSZP has no threshold voltage owing to its homeotropic/planar hybrid alignment regions, and it can find applications in imaging, laser processing, and optical manipulation.

The hard x-ray nanotomography microscope at the advanced light source.

Abstract: Beamline 11.3.1 at the Advanced Light Source is a tender/hard (6-17 keV) x-ray bend magnet beamline recently re-purposed with a new full-field, nanoscale transmission x-ray microscope. The microscope is designed to image composite and porous materials possessing a submicrometer structure and compositional heterogeneity that determine materials' performance and geologic behavior. The theoretical and achieved resolutions are 55 and <100 nm, respectively. The microscope is used in tandem with a <25 nm eccentricity rotation stage for high-resolution volume imaging using nanoscale computed tomography. The system also features a novel bipolar illumination condenser for the illumination of an ∼100 μm spot of interest on the sample, followed by a phase-type zone plate magnifying objective of ∼52 µm field of view and a phase detection ring. The zone plate serves as the system objective and magnifies the sample with projection onto an indirect x-ray detection system, consisting of a polished single crystal CsI(Tl) scintillator and a range of high-quality Plan Fluorite visible light objectives. The objectives project the final visible light image onto a water-cooled CMOS 2048 × 2048-pixel2 detector. Here, we will discuss the salient features of this instrument and describe early results from imaging the internal three-dimensional microstructure and nanostructure of target materials, including fiber-reinforced composites and geomaterials.

Trapezoid-kinoform zone plate lens – a solution for efficient focusing in hard X-ray optics

Abstract: X-ray microscopes are powerful tools in the nano-inspection of materials owing to their ultra-high resolution at the molecular level. However, the focusing efficiency of binary zone plate lenses as key components in such probes is merely 5% in practice, hindering their application in advanced scientific research. Although kinoform zone plate lenses are in principle supposed to possess high efficiency beyond binary ones, little progress has been reported so far due to the shortage of both a theoretical calculation approach and greyscale lithography for generating fine three-dimensional (3D) kinoform zones of the lenses. This paper reports our theoretical work for a modified beam propagation method to compute the focusing performance and state-of-the-art 3D greyscale electron beam lithography for kinoform zone plate lenses. Three different zone shapes - binary, kinoform and top-flat kinoform (nicknamed the trapezoid-kinoform) - were compared both theoretically and experimentally. Theoretical calculations suggest, for the first time, that the trapezoid-kinoform zone plate gives rise to the highest focusing efficiency among the three lenses, which was proved by optical characterization of the fabricated lens with hard X-rays. As high as 40% of the focusing efficiency by Au trapezoid-kinoform lenses with resolution of 250 nm at 8 keV has been achieved, which is two times higher than that of binary zone plate lenses. The origin of the enhanced efficiency in the trapezoid-kinoform zone plate lens was explained by the joint contributions from both the refraction through the kinoform slope and the diffraction through the top flat part of the trapezoid-kinoform zone plate. Such a breakthrough in focusing efficiency sheds light on the further development of X-ray lenses with both high resolution and high efficiency.

Achromatic acoustic generalized phase-reversal zone plates

Abstract: We report an achromatic acoustic generalized phase-reversal zone plate by harnessing the response of dipole and monopole, which eliminate the chromatic aberration of conventional zone plates. The focusing properties of the proposed metalens are compared with that of the conventional Soret-type Fresnel zone plate (FZP) in both experiments and simulations. Due to the combination of the phase-reversal characteristic and the tunable transmission phase induced by dipole and monopole, an achromatic high efficient focusing is confirmed by experiment in the frequency range from 3350 to 3950 Hz, with the focal intensity of achromatic metalens being approximately twice that of Soret-type FZP. The proposed achromatic metalens has potential applications in the broad field of acoustics, such as imaging and energy harvesting.

An Annular Fresnel Zone Plate without Central Spots Fabricated by Femtosecond Laser Direct Writing

Abstract: In recent years, micro-annular beams have been widely used, which has expanded the possibilities for laser processing. However, the current method of generating an annular beam still has shortcomings, such as spot energy at the center of the produced beam. In this study, a Fresnel zone plate with an annular structure was machined using a femtosecond laser. After focusing, an annular laser beam without a spot in the center was obtained, and the radius and focal length of the annular beam could be easily adjusted. In addition, two annular Fresnel zone plates were concentrically connected to obtain a concentric double-ring beam in the same focal plane. The simulation and experimental results were consistent, providing effective potential for applications related to nontraditionally shaped laser beams.

X-ray zooming microscopy with two Fresnel zone plates.

Abstract: We propose a variable-magnification full-field x-ray microscope using two Fresnel zone plates (FZPs). By moving the positions of the two FZPs, the magnification can be continuously changed even if the sample and camera positions are fixed. It was demonstrated that the magnification can be changed in the range of 25-150× using a hard x-ray beam at 14.4 keV. Using the first FZP as a convex lens and the second FZP as a concave lens, high magnification can be achieved at a short camera length. Even under the condition of a camera length of about 7 m, a magnification higher than 300× was achieved, and a line and space pattern with a pitch of 40 nm was observed at 10 keV. By inserting a knife edge at an appropriate position in the optical system, a phase-contrast image can be easily obtained, which is useful for soft-tissue observation of biological samples.

Comparison of the shape of focal spots in terms of intensity and energy flux for a high-aperture zone plate and a spiral zone plate

Abstract: Using a finite-difference time-domain method, it has been shown that focal spots generated when tightly focusing a linearly polarized Gaussian beam by a Fresnel zone plate (FZP) and when focusing a Gaussian beam with an embedded optical vortex by a spiral zone plate (SZP) have different patterns of the intensity and energy flux. The most significant differences are observed when the value of the topological charge (TC) is equal to three. The energy flux has an annular distribution when the Gaussian beam is focused by the FZP, while the SZP produces a field whose patterns of intensity and energy flux have three local maxima. The number of local maxima corresponds to the order of the SZP. At a certain distance from the focus, the petal structure of the intensity (and energy flux) changes to a ring distribution.

3D‐Printed Holographic Fresnel Lenses

Abstract: Additive manufacturing processes are capable of fabricating optical devices, including the production of contact lenses, waveguides, and Fresnel lenses used in a variety of applications. This study presents a novel fabrication method for high‐quality Fresnel lenses through a vat photopolymerization 3D printing method. Here, the 3D printing process is integrated with the micro/nanostructure fabrication to produce 3D optical components with imprinted micro/nanostructures in a single step. This straightforward approach allows imprinting a micro‐pattern (5 μm features size) onto the flat surface of a 3D‐printed Fresnel lens, achieve light focusing properties along with holographic rainbow effects. The printed lenses achieve focal lengths within ≤8 mm deviation from the predicted values. Such holographic Fresnel lenses are highly desirable in imaging‐based miniature spectrometers for mechanoluminescence sensoring. Thus, the masked stereolithography (MSLA) based 3D printing process can produce normal and holographic Fresnel lenses, vital in optical sensing and communication.

High efficiency and scalable fabrication of fresnel zone plates using holographic femtosecond pulses

Abstract: Abstract To meet the growing demand for photonic integration and device miniaturization, planar diffractive Fresnel zone plates (FZPs) are widely applied in integrated optical systems. However, challenges remain in fabricating FZPs with high efficiency and satisfying the requirement for cross-scale fabrication. This paper details a high efficiency method for fabricating ultrathin FZPs of different scales on metal films by using holographic femtosecond lasers. The FZPs are split into a series of element patterns that are printed in order by using corresponding modulated femtosecond pulses. The fabricated FZPs are spliced by the printed element structures with no FZP size limitation in theory. FZPs with an area varying across three orders of magnitude are presented to demonstrate the capability of cross-scale fabrication. The fabricated FZPs possess an excellent broadband focusing and imaging ability in the visible spectrum. Furthermore, the fabrication of other functional ultrathin lenses, such as axial multifocal zone plates, petal-like zone plates, and FZP arrays, is described, revealing the wide potential for the flexible and scalable fabrication method in on-chip integrated optical systems.

Terahertz Fresnel-zone-plate thin-film lens based on a high-transmittance double-layer metamaterial phase shifter.

Abstract: Planar diffractive lenses, with metamaterial artificial structures and subwavelength thickness, provide unique and flexible platforms for optical design in the terahertz (THz) regime. Here, we present a metamaterial-based Rayleigh-Wood Fresnel-zone-plate (FZP) thin-film lens designed to focus a monochromatic THz beam at 1.0 THz with a high transmittance of 80%, short focal length of 24 mm, and subwavelength thickness of 48 µm. Specifically, the FZP lens is composed of 8 alternating concentric zones through a polymer film substrate, where odd zones are patterned with double-layer un-split ring resonators (USRRs) that provide a polarization-independent phase shift of π/2 compared to un-patterned even zones. Both simulation and experiment confirm that our FZP lens creates a focused beam at the designed frequency of 1.0 THz by constructive interference through alternating concentric metamaterial-patterned and un-patterned zones, producing a diffraction-limited resolution of 0.6 mm for imaging applications. In contrast to conventional approaches in which the uniform periodic array of metamaterial unit cells has been treated as an effective material, we newly find that double-layer USRRs can work as an independent meta-atom without degradation of its performances, which benefits the behavior of small arrays of double-layer USRRs located in the outer zones of the FZP lens. Such a planar thin-film lens would enable us to realize compact and lightweight THz systems.

Direct Emission of Focused Terahertz Vortex Beams Using Indium‐Tin‐Oxide‐Based Fresnel Zone Plates

Abstract: Terahertz (THz) vortex beams with helical wavefronts promise many important applications ranging from high‐speed wireless communications to super‐resolution imaging. Conventional methods to generate THz beams mostly rely on manipulating and converting the incident THz beams. Herein is proposed and experimentally demonstrated how the patterned indium tin oxide (ITO) film, i.e., ITO Fresnel zone plate (ITO‐FZP), enables direct emission of focused THz vortex beams with desired orbital angular momentums. Such THz vortex‐beam emitters are based on the straightforward nonlinear THz emission through the patterned ITO film under femtosecond laser excitation. The proposed approach greatly integrates THz emission and vortex‐beam generation processes, which is low cost, robust, and easy to fabricate.

Diffraction of laser radiation by a binary zone plate with fractional order

Abstract: Hybridly polarized beams have attracted increasing attention in recent years. Due to the features of spatial polarization and phase singularity, they can be used in STED microscopy, as optical tweezers, in nanoprocessing, to excite surface plasmon polaritons, in nonlinear optics, in quantum optics, and in telecommunication technologies. In this work, using the FDTD method, we simulated the passage of laser radiation through a binary spiral zone plate with a fractional order m=0.5 and a focal length of 0.532 μm. Quartz glass n=1.5 was assumed as the material for the relief of the zone plate. The zone plate radius was 4 μm. A TE polarized Gaussian beam with a wavelength of 0.532 μm was fed to the input. In this work, the intensity distribution and the Poynting vector in focus were studied. The possibility of forming an optical vortex with a fractional order was demonstrated.

Diffractive analysis of a chiral Fresnel zone plate with controllable on-axis foci and dual imaging

Abstract: Wave propagation through a chiral Fresnel zone plate (FZP) using diffractive analysis is adapted from the purely achiral FZP by incorporating the bimodal results for (RCP/LCP modes via Fresnel coefficients) corresponding to a magnetic chiral slab examined, leading to controllable on-axis foci and dual imaging.

Three-dimensional active tunable spiral zone plates for selective adjusting of optical vortex and depth of focus

Abstract: Diffractive optical elements (DOEs) have a number of advantages over refractive or reflective optical elements, including improved dispersion, wider profile tolerances, and greater design freedom. A critical DOE, the Fresnel zone plate (FZP) is widely used in a variety of optical systems, including nano/micro focusing lenses, X-ray imaging, and beam shaping. Optics research on tunable functional devices has a long history of being an enticing field, having a significant impact on the evolution of optical information technology and photonic integrated circuits. The active-spiral Fresnel zone plate (ASFZP), the nanoscale polymer-dispersed liquid crystals (LC) tunable Fresnel lens, and the tunable spiralized Fresnel zone plate are all examples of tunable zone plates. All previously described tunable zone plates achieve tunability by modifying their properties or shape in two dimensions along the lateral plane. In this study, we demonstrate an active flexible three-dimensional tunable spiral plate (3DSP). Rather than alternating bright and dark zones, these zone plates have a spiral pattern in three dimensions. These zone plates enable tunability in both wavelength and depth of focus by actively modifying the lateral and vertical planes. These zone plates achieve a combination of selective wavelength transmission and predefined depth of focus by activating the 3DSP to predefined settings.

Light focusing by Fresnel phase plates with an inclined zone profile

Abstract: The results of numerical simulation of optical radiation focusing on a mesowavelength Fresnel phase zone plate (ZP) with zones having an inclined profile are presented. In order to reveal the regularities in the formation of the focal spatial structure, the optical field was calculated in the case of diffraction of a monochromatic optical wave by a single ZP. It is shown that the basic parameters of the focal region (intensity, longitudinal and transverse dimensions, focal distance) are sensitive to the angle of inclination of the annular zones of the ZP. By changing the inclination of the edges, it is possible to optimize focusing and achieve its significant enhancement, which, depending on the focal length of the plate, can be up to 40%.

Enhancement of near-field subwavelength focusing using a solid immersion Fresnel zone plate with radially polarized incidence

Abstract: A solid immersion Fresnel zone plate (SI-FZP) is designed, and its near-field diffraction characteristics are analyzed using the vector angular spectrum (VAS) method. The analytical VAS model of formulism for the electric field vector transmitted from a binary amplitude and/or phase circular SI-FZP is obtained for any polarization of incidence. Numerical calculations show that, when the solid film immersing a high-numerical-aperture FZP is truncated close to the FZP’s focus in a single homogeneous medium, the focusing intensity in the vicinity of the SI-FZP–air interface can be improved dozens of times in magnitude for radially polarized incidence, compared with the FZP’s far-field focusing in the single medium without an interface. The validity of the proposed analytical VAS model of formulism to analyze SI-FZP’s diffraction problems has been affirmed by comparison with numerical results obtained by the finite-difference time-domain simulation.

Experimental confirmation of the concept of the photon spatial switch based on off-axis zone plate in the millimeter range

Abstract: The results of an experimental verification of the concept of the previously proposed all-optical wavelength-selective multichannel switch based on an off-axis Fresnel zone plate in the millimeter wavelength range without the use of micromechanical devices or non-linear materials are presented. A laboratory prototype of such a device is considered and its main parameters are discussed. It is shown that the optical isolation of switched channels for a switch based on an off-axis zone plate can reach 15 dB at a frequency difference of 25 GHz in the frequency range of 93–136 GHz.

A Dedicated Endstation for Waveguide-based X-Ray Imaging

Abstract: X-ray microscopy has emerged as a powerful and versatile imaging technique in many fields of science over the last years, offering insights in opaque media at high spatial resolution. A major challenge remains the fabrication of suitable X-ray lenses, e.g., Fresnel zone plates or compound refractive lenses. In an alternative approach of a lensless imaging scheme the sample is illuminated by a coherent X-ray beam. The sample information is then reconstructed from the recorded diffraction signal by numerical iterative algorithms. Within this thesis the basics of lensless holographic imaging with X-Ray waveguides are summarised and extended to the concept of waveguide-based X-ray interferometry. The specific instrumentation required for the conceptual experiments of waveguide-based holographic imaging is explained and illustrated by the obtained results. Based on the results of these conceptual experiments a dedicated synchrotron endstation for waveguide-based holographic imaging was designed and built. The specifications and properties of the Kirkpatrick-Baez focussing mirrors and other mechanical and optical components are described in detail, along with the instrument control system and various available detectors. First commissioning results prove the imaging abilities of the presented endstation.

A dielectric Kinoform zone plate with 15 nm resolution and high efficiency for soft X-ray optics

Abstract: Abstract X-ray microscope as an important nanoprobing tool is expected to play a powerful role in nano-inspections of materials. Despite the fast advances of high resolution focusing/imaging reported, the diffraction efficiency of existing binary zone plates as the lenses in the microscope is mostly around 5% in practice and rapidly goes down to 1-2% when the resolution approaches 10 nm, failing its applications in advanced scientific research. Zone plates with Kinoform profile are supposed to be high efficient, little progress for achieving both high resolution and high efficiency has been reported. The conflict between the resolution and the efficiency in X ray optics has become a long-lasting bottleneck in the further development of X-ray microscope. Based on our earlier success in developing high efficiency Kinoform zone plates by greyscale electron beam lithography, we proposed, in this work, a new zone plate structure by combing a dielectric Kinoform zone plate with an atomic layer deposited HfO2 zone plate to achieve high resolution focusing/imaging with high efficiency. Beam propagation method was applied in designing and optimizing Kinoform shapes of the zones, greyscale and/or binary electron beam lithography was carried out for generating both 3D Kinoform as well as rectangular zones with aspect ratio of 23/1 in dielectric resist, and finally high-quality atomic layer deposition of HfO2 was conducted to form the 15-nm wide outermost zone. Optical characterizations by an in-house developed soft X ray microscope demonstrated 15-nm resolution focusing/imaging with over 7% efficiency, which is the highest with such a resolution as far as our awareness. The origin of such an improvement behind the proposed novel lenses is interpreted by our BMP calculation results and the comparisons with existing performances by other reports in literature was discussed.

Deformation field mapping of the X-ray silicon Fresnel Zone Plate

Abstract: The characterization of the deformations of the circular Fresnel Zone Plate (FZP) by the X-ray diffraction imaging technique is presented in this paper. The research was performed at the ID06 ESRF beamline using the 12.38 keV radiation energy. During the experiment, the contour map of the FZP deformation field was obtained. This map was used in the reconstruction of the surface curvature profile at three points: at the FZP center, 60 μm, and 120 μm below the FZP center. As result, the FZP with 242 zones has a concave profile in its center and a convex profile near the outermost zones. The inflection points close to the 115th zone were observed. This technique can be used not only for the characterization of the conventional binary FZP but also for the Multilayer Laue Lenses and FZP with multilevel, and kinoform profiles.

Real-time interactive computer-generated hologram using Fresnel zone plate extension method

Abstract: Holographic display can reconstruct the optical wave field of three-dimensional (3D) scenes. Computer- generated hologram (CGH) can simulate the optical transmission process from the 3D object to the hologram plane and avoid complicated experiments. Wavefront recording plane (WRP) is a fast algorithm for CGH, which is placed between the 3D object and the CGH. However, the computational amount is increased when the depth range of the 3D object is expanded. In this paper, we propose a fast calculation algorithm for real-time interactive CGH using a novel Fresnel zone plate (FZP) extension method and ray tracing. In the first step, ray tracing is used to get the amplitude value and the depth value of each object point. The maximum resolution of each FZP is determined according to the distance from the object point to the WRP. In the second step, a preset square portion of each FZP is used to calculate the complex amplitude of the WRP. Then diffraction calculation is performed from the WRP to the hologram plane for calculating CGH, and the computational domain of each FZP is gradually extended as the number of frames increases. The above calculation is repeated when interacting. The computational complexity is effectively reduced because the resolution of each FZP is increased until the maximum resolution is reached, instead of directly calculating each FZP with the maximum resolution. Experiments demonstrate the proposed method can generate CGH in real-time. The resolution of the hologram is 1024x024 and the CGH generation rate is 45.81 frames per second when interacting.

Точечная фокусировка дифрагированной на кристаллической пластинке двумерно δ-образной рентгеновской волны, с использованием эллиптической зонной пластинки

Abstract: Рассмотрена возможность двумерной фокусировки жесткого рентгеновского излучения, дифрагированной на идеальной кристаллической пластинке. Предполагается, что имеет место лауэвская геометрия дифракции, а волна, падающая на кристаллическую пластину, имеет δ-образную форму по двум взаимно перпендикулярным направлениям тангенциальной к волновому вектору плоскости. В качестве фокусирующего элемента используется френелевская зонная пластинка с эллиптическими зонами. Проведено численное моделирование фокусировки. Դիտարկված է իդեալական բյուրեղական թիթեղի վրա կոշտ ռենտգենյան ճառագայթման երկչափ կիզակետման հնարավորությունը։ Ենթադրվում է, որ իրականանում դիֆրակցիայի Լաուէ երկրաչափությունը, իսկ բյուրեղական թիթեղի վրա ընկնող ալիքը, ունի δ-ալիքի ձև ալիքային վեկտորին ուղղահայաց հարթության երկու փոխուղղահայաց ուղղություններով։ Որպես կիզակետող սարք, օգտագործվում է էլիպտական գոտիական թիթեղ։ Իրականացված է կիզակետման թվային մոդելավորում։ The possibility of the two-dimensional focusing of hard X-rays, diffracted on an ideal crystalline plate is considered. It is assumed, that the Laue geometry of diffraction is take place, and the wave incident on crystalline plate, in the wave-front plane is δ-shaped in both directions: parallel and perpendicular of reflection plane. The Fresnel zone plate with elliptical zones is used as a focusing device. A numerical simulation of the focusing is carried out.