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Showing papers on "Zone plate published in 1986"


Patent
Roger H. Appeldorn1
09 Sep 1986
TL;DR: In this article, a thin flexible fresnel lens is used to focus incident solar radiation not normal to the lens onto a target area by refraction in a solar energy concentrator.
Abstract: A solar energy concentrator (20) including a thin flexible fresnel lens (24) for focusing incident solar radiation not normal to the lens (24) onto a target area (26) by refraction. The fresnel lens (24) is supported or suspended above the target area (26) by a frame (22) and folded along at least one line or region (28) parallel to the refractive prisms (32) of the lens (24) which are generally parallel to the axis of the target area (26) whereby the fresnel lens (24) opens toward the target area (26). Thus the fresnel lens (24) is so positioned so as to allow it to bow and flex under wind loads, gravity and other environmental factors without causing significant deterioration in the efficiency of the system.

77 citations


Patent
19 Feb 1986
TL;DR: In this article, a pattern-form Fresnel hologram is formed by exposing a photosensitive resin layer to an interference light obtained from interference between an object light beam and a reference light beam both obtained by dividing a single coherent light.
Abstract: An identification article comprise a substrate and a pattern-form Fresnel hologram provided as an identification information providing layer on the surface or in the interior of the substrate structure. The pattern-form Fresnel hologram is formed by (a) forming a Fresnel hologram by exposing a photosensitive resin layer to an interference light obtained from interference between an object light beam and a reference light beam both obtained by dividing a single coherent light, (b) exposing the Fresnel hologram to light transmitted through a mask pattern, (c) fabricating a pattern-form Fresnel hologram by developing the Fresnel hologram, and (d) reconstructing the pattern-form Fresnel hologram thus obtained. The identification article is verified by projecting a monochromatic light onto the hologram to reproduce an image and projecting this image on a screen or detecting it with a light detector.

51 citations


Patent
06 Mar 1986
TL;DR: In this article, an optical alignment apparatus and method for a semiconductor lithography mask and wafer utilizes two monochromatic light sources of different wavelengths of different intensity for more accurate printing of mask patterns on the wafer.
Abstract: An optical alignment apparatus and method for a semiconductor lithography mask and wafer utilizes two monochromatic light sources of different wavelengths. The mask contains targets in the form of linear Fresnel zone plates and the wafer contains a reflecting grating. Incident illumination from the two light sources illuminates the mask targets and is reflected from the wafer gratings in various intensity depending on the physical characteristics of the wafer and mask layers and thicknesses and by the targets. A detector detects the strongest of the diffracted return beams from each of the monochromatic light sources and uses the strongest to align the targets and grating on the mask and wafer for more accurate printing of mask patterns on the wafer.

47 citations


Journal ArticleDOI
TL;DR: Fresnel lenses were fabricated by the patterned proton-exchange technique in titanium-diffused lithium niobate waveguides with characteristics of nearly diffraction-limited focus spot size and efficiency up to 70% to construct an integrated-optic rf spectrum analyzer of 1-GHz bandwidth and 2-MHz resolution.
Abstract: Fresnel lenses were fabricated by the patterned proton-exchange technique in titanium-diffused lithium niobate waveguides. The large change in refractive index available with the proton exchange allows fabrication of a high-efficiency thin Fresnel lens. Lens characteristics of nearly diffraction-limited focus spot size and efficiency up to 70% were obtained. The use of the lens to construct an integrated-optic rf spectrum analyzer of 1-GHz bandwidth and 2-MHz resolution is also demonstrated.

35 citations


Journal ArticleDOI
TL;DR: In this paper, the feasibility of using photoresist Fresnel zone plates as micro-optic components was examined experimentally, and they used deep UV lithography to fabricate zone plates with submicron pitch, and nearly diffraction-limited spot formation and high efficiency were achieved.
Abstract: The feasibility of using photoresist Fresnel zone plates as micro-optic components was examined experimentally. Deep UV lithography was used to fabricate zone plates with submicron pitch, and nearly diffraction-limited spot formation and high efficiency were achieved. The direct collimation of a semiconductor laser beam was demonstrated.

23 citations


Proceedings ArticleDOI
01 Jan 1986
TL;DR: In this article, the capabilities of an imaging x-ray microscope using zone plate optics as focussing elements were demonstrated gradually, and the authors built a scanning X-ray microscopy using zone plates.
Abstract: During the past years the capabilities of an imaging x-ray microscope using zone plate optics as focussing elements were demonstrated gradually [22.1,2]. In addition to this microscope we built a scanning x-ray microscope using zone plates. It has been developed because the radiation dose exposed to an object in such a system is reduced significantly. For biological applications in the resolution range below δ ≲ 0.1 pm this is important, as the dose transferred to an object increases drastically with increasing resolution [22.3].

22 citations


Journal ArticleDOI
TL;DR: In this article, a convenient expression describing the location of Fresnel diffraction patterns when a diffracted spherical wave is focused by a lens is given, and experimental results confirm the predicted positions of 26 axial extrema corresponding to integer numbers of the Fresnel half-period zones.
Abstract: A convenient expression describing the location of Fresnel diffraction patterns when a diffracted spherical wave is focused by a lens is given. Experimental results confirm the predicted positions of 26 axial extrema corresponding to integer numbers of Fresnel half-period zones. Experimental radial intensity profiles are presented for some of these positions.

18 citations


Proceedings ArticleDOI
01 Jan 1986
TL;DR: In this article, a planar-structure acoustic-microscopy lens was designed according to the theory of Fresnel zone plate, and demonstrated its good focusing capability using an ordinary chemical etching technique.
Abstract: In the previous report, t he authors proposed a new planar-structure acoustic-microsc ope lens designed according to the theory of Fresnel zone plate, and demonstrated its good focusing capability. Since the l ens is composed of a number of concentric annular grooves of uniform depth on its radiation plane, it has an advantage over the conventional acoustic lens with a spherical concave in being fabricated easily using a photolithographi c technique. In our first model of the planar lens, which had an aperture angle of 47.3" and operated at 100 MHz, the grooves could be formed successfully using an ordinary chemical etching technique. However, the formation of finer grooves is inevitably limited by the undercutting effect so far as a wet-process is used. Therefore, some advanced photolithographi c technique s hould be employed for fabricating the lens with a wider aperture a ngle and a higher o peration frequency. Recently, the authors have introduced the ECR (electron cyclotron resonance) reactive ion etching technique for forming fine grooves. Using this dry-process, a planar lens designed for an operation frequency of 200 MHz and an aperture a ngle of 90' has been obtained. I n the present report, we describe the fabrication process and some results of imaging experiments by an acoustic microscope equipped with the p lanar lens.

16 citations


Patent
18 Jul 1986
TL;DR: In this article, a reductive projection method was proposed for a soft X-ray lithographic system employing proximity exposure method, where a mask pattern or an original to be copied is positioned between the reflector and the Fresnel zone plate (FZP) so that the soft X ray will transmit through the mask pattern to form a reduced image or copy thereof on a resist coated target substrate.
Abstract: Conventional soft X-ray lithographic system employing proximity exposure method is advanced by rendering the system feasibility of reductive projection method which has been proved of its merit in photo-lithography and the present inventive imaging system comprises basically a soft X-ray source which is emissive like a point source, a spherically concaved reflector to converge the soft X-ray onto a Fresnel zone plate (FZP) wherein a mask pattern or an original to be copied is positioned between the reflector and the FZP so that the soft X-ray will transmit through the mask pattern to form a reduced image or copy thereof on a resist coated target substrate. Therefore, the present invention will be most advantageously applied to patterning jobs in IC industry.

16 citations


Journal ArticleDOI
Yuzo Ono1, Nobuo Nishida1
TL;DR: In this paper, a semianalytical method to solve the correction phase is proposed, in which the z-directional cosine of a diffracted light ray is dealt with as an estimated constant.
Abstract: To optimize the phase-transfer function of holographic optical elements, a semianalytical method to solve the correction phase is proposed, in which the z-directional cosine of a diffracted light ray is dealt with as an estimated constant. Numerically, the confusion circle radius has been reduced to 1/120 for a holographic laser scanner example by this method, with rapid convergence. It is clarified that, for the generalized holographic zone plate generated with two spherical waves, the hologram phase-transfer function is well optimized for a laser-beam scanner without correction.

10 citations


Proceedings ArticleDOI
01 Jan 1986
TL;DR: In this paper, a beamline for laterally resolved photoelectron-spectroscopy (PESC) using synchrotron radiation from dipole magnets is proposed.
Abstract: At BESSY a beamline for applications in laterally resolved photoelectron-spectroscopy is planned. The performance of such a small spot scanning ESCA line (ESCAN) using synchrotron radiation is described. In the present design a combination of a stigmatically focussing SX-700 type plane grating monochromator and a zone plate create a microspot of less than 5 μm in diameter. The flux concentrated in that spot should make small spot ESCA possible even with synchrotron radiation from dipole magnets.

Journal ArticleDOI
Yuzo Ono1, Nobuo Nishida1
TL;DR: In this article, a holographic zone plate generated by subtracting the spherical wave phase is proposed, that is, a hologram generated by using two divergent or convergent spherical waves.
Abstract: A holographic zone plate generated by subtracting the spherical wave phase is proposed, that is, a hologram generated by using two divergent or convergent spherical waves. This holographic zone plate can correct the increase in focal power in a radial direction in contrast with the interferometric zone plate. Use of this holographic zone plate for f x O and collimating lenses is analyzed. For an f x O lens, it is shown that an optimum combination of recording spherical waves exists that satisfies both scan linearity and image field flatness. For a collimating lens for a laser diode, it is shown that aberration can be corrected for different playback wavelengths from that used during recording.

Journal ArticleDOI
Giovanni Vannucci1
TL;DR: In optical communication systems, which use mostly narrowband light sources (lasers, LEDs), tuned Fresnel lenses may offer a lower cost alternative to conventional lenses without sacrificing focusing performance.
Abstract: We propose a technique to manufacture Fresnel lenses where the grooves are phase-synchronized at a given wavelength. This means that the light from different grooves will superpose coherently at the focal point at the specified wavelength. The focusing performance of such a “tuned” Fresnel lens will be better than that of ordinary Fresnel lenses by orders of magnitude and can, in principle, equal the performance of a conventional lens of the same diameter (diffraction limit). In optical communication systems, which use mostly narrowband light sources (lasers, LEDs), tuned Fresnel lenses may offer a lower cost alternative to conventional lenses without sacrificing focusing performance.

Patent
01 Mar 1986
TL;DR: In this article, a transducer and a sound absorbing body are stuck to the outside peripheral surface of an acoustic optical crystal plate, and the plate is stuck to a columnar throughhole in the center.
Abstract: PURPOSE:To form an image on a fixed screen without replacing a Fresnel zone plate with respect to an incident light of a different wavelength by constituting said plate of an acoustic optical system element formed by sticking a transducer and a sound absorbing body to one side and the other, respectively, and a transducer driving device for supplying a vibrating signal. CONSTITUTION:An acousto-optical crystal 21 is cut to a disk, a sound absorbing body 22 of an acoustic wave is stuck to the outside peripheral surface of the acoustic optical crystal plate 21 opening a columnar through-hole in the center, and a transducer 23 is stuck to the through-hole of the center. A transducer driving device 3 supplies a vibration voltage to the transducer 23 by a trigger signal from a trigger signal generating device 4, and a trigger signal generating device 4 sends out the same trigger signal through a delay device 5 to not only the transducer driving device 4 but also a Kerr cell 7. When a driving voltage of a Kerr cell driving device 6 is impressed, a rotation is generated on the plane of polarization only during that time, and a light transmits through. An image pickup surface 12 of an image pickup device 11 is placed on the image forming surface of an acoustic optical Fresnel zone plate determined by a waveform of an acoustic wave supplied by the transducer 23 and a wavelength of an incident light.

Book ChapterDOI
01 Jan 1986
TL;DR: In this article, the Huygens-Fresnel wave propagation principle is used to define the phase of a spherical wavelet, and the effect of the wavelet on the soft X-ray detector is analyzed.
Abstract: Zone plates may be considered to be circular diffraction gratings with radially increasing line densities. Their focusing properties have long been well known,(1) and they offer perhaps the best chance in the foreseeable future of diffraction-limited imaging using soft X rays, where they are used in transmission. Figure 8.1 shows the requirement for focusing, namely that radiation emitted from an object point P is focused to an image point P’. The complex disturbance at P’ due to a spherical wavefront emitted by P is $$Y\left( {P'} \right) = A\exp \left[ {ik(R + R')} \right]/(R + R')$$ (8.1) where A is the amplitude at unit radius from P, R is the perpendicular distance from P to the focusing device, R’ is the perpendicular distance from the focusing device to P’, and k is the wavenumber \(( = 2\pi /\lambda )\). In equation (8.1) the periodic time factor has been omitted since soft X-ray detectors only respond to time-averaged signals, and an inclination factor expressing the amplitude variation with distance has been ignored since (due to the small sizes of the optical components) only small angle diffraction need be considered. Using the Huygens-Fresnel wave propagation principle, each point on the wavefront emitted by P is considered to be a point source of spherical wavelets; all such points are in phase. The total effect at P’ is found by summing the effects from all points on the wavefront with relative phases at P’ determined solely by the optical distances from the wavefront to P’. If two signals on the wavefront have an optical path difference to P’ of an integral number of wavelengths, they will contribute in phase (i.e., interfere constructively), while if the optical path difference is an odd-integral number of half-wavelengths, they will contribute completely out of phase (i.e., interfere destructively). The wavefront may be imagined as being divided into a set of Fresnel (or half-period) zones by spheres differing in radius by \(\lambda /2\) and centered on P’ Adjacent zones will then transmit radiation with opposite signs of phase—the resultant disturbance from these zones gives the propagating spherical wave in free space. If alternate zones are blocked, then the disturbances at P’ will have the same sign of phase and the summation shows an increase proportional to the number of zones. Note that it is not necessary for the distance R + R’ between P and P’ to be an integral number of half-wavelengths; in Figure 8.1, δ is introduced to take account of this, i.e., δ corresponds to an overall arbitrary phase.

Patent
06 Aug 1986
TL;DR: In this article, the authors proposed a method to obtain the title optical element having a dynamic stability and capable of maintaining a high optical performance by inserting a desired pattern of an Au layer into a thin film of a polyparaxylene vapor-deposited on the title element.
Abstract: PURPOSE:To obtain the title optical element having a dynamic stability and capable of maintaining a high optical performance by inserting a desired pattern of an Au layer into a thin film of a polyparaxylene vapor-deposited on the title element. CONSTITUTION:A metallic pattern G of the Fresnels zone plate or a transparent type grating for a soft X ray use is buried into the polyparaxylene layer P to hold the metallic pattern G with the polyparaxylene. The Au metal is often used as a material of the metallic pattern for the diffraction. The pattern for the diffraction which is formed in a fretwork state on the thin film is a very weak. However, said pattern can increase a strength by burying it in the polyparaxylene. As the polyparaxylene itself having <=1mum thickness has a sufficient transparency in <=100mum short wavelength, a loss of a luminous energy is small, and a desired diffraction phenomenon of the title element is not affected on comparing to an element strengthened with the metallic pattern.

Journal ArticleDOI
TL;DR: In this article, the angle eikonals for plane and spherical zone plates of transmission and reflection types were determined for the Seidel coefficients of a thin lens as its index of refraction becomes infinity.
Abstract: The angle eikonals are determined for plane and spherical zone plates of transmission and reflection types. From them, the Seidel coefficients are obtained. These are compared with those of a thin lens as its index of refraction becomes infinity and with Murty’s aplanatic reflective zone plate.

Proceedings ArticleDOI
01 Jan 1986
TL;DR: In this article, two condenser zone plates were constructed for the use in the Gottingen scanning x-ray microscope and the efficiency of such a condenser should be as high as possible to minimize the loss of radiation.
Abstract: With the Gottingen scanning x-ray microscope the synchrotron source is imaged by x-ray optics into a monochromatic small scan spot, through which a specimen can be moved. Hereby one part of the optics, the condenser zone plate and a pinhole, works as a linear monochro-mator in the wavelength region of λ= 2.36 nm to λ= 4.5 nm. The efficiency of such a condenser should be as high as possible to minimize the loss of radiation. Phase zone plates have a four times higher efficiency in the first order of diffraction than amplitude zone plates. Two condenser zone plates, KZP4 and KZP5, have been constructed so that they are well suited for the use in the scanning microscope. These zone plates have been made holo-graphically by superposing two wavefronts of laser light in an specific designed optical arrangement and exposing the zone plate structure into a photoresist. Using reactive ion etching (RIE) the structure has been transformed into Germanium. The thickness of the zone plate has been chosen to show at λ = 2.36 nm a phase effect. The efficiency has been measured at the Berliner Elektronenspeicherring Gesellschaft fUr Synchrotronstrahlung m.b.H., Berlin.

Proceedings ArticleDOI
01 Jan 1986
TL;DR: A review of optical systems for soft x-radiation 0.5 nm ≤ λ ≤ 4.5nm is given in this paper, where the authors discuss zone plate fabrication methods and accuracy requirements.
Abstract: A review of optical systems for soft x-radiation 0.5 nm ≤ λ ≤ 4.5 nm is given. Grazing incidence and multilayer mirrors are shortly discussed. Zone plate fabrication methods and accuracy requirements are discussed and some aspects of holographic zone plate fabrication are described.

Journal ArticleDOI
TL;DR: In this article, the third and fifth-order wavelength shift aberrations for an off-axis holographic zone plate for the higher orders were discussed, and numerical calculations of the aberratures were presented.
Abstract: The third- and fifth-order wavelength-shift aberrations for an off-axis holographic zone plate for the higher orders are discussed, and numerical calculations of the aberrations are presented. A stigmatic point image can be obtained in the nth diffracted order if the wavelength-shift ratio is equal to 1/n.

Journal ArticleDOI
TL;DR: In this paper, an improved optical design for a microscopy beam line at Hefei is presented, utilizing a linear monochromator which consists of a diaphragm and a condenser zone plate selected from several ones with different parameters for different wavelength ranges.
Abstract: An improved optical design for a microscopy beam line at Hefei is presented, utilizing a linear monochromator which consists of a diaphragm and a condenser zone plate selected from several ones with different parameters for different wavelength ranges. The progress and plan for the construction of these condenser zone plates are also described.

Journal ArticleDOI
TL;DR: In this article, the authors discuss the properties of partially coherent radiation generated by X-ray lasers, undularcrrs, and laser produced plasmas, and illustrate radi'ative performance in terms of both coherent power and spectral brightness, for both peak and average values.
Abstract: In this paper we discuss the properties of partially coherent radiation generated by X-ray lasers, undularcrrs, and laser produced plasmas. We discuss spatial and temporal coherence properties, experiments involving X-ray microscopy and microholography which benefit from varying degrees of coherence, and we illustrate radi'ative performance in terms of both coherent power and spectral brightness, for both peak and average values. Introduction In recent years we have seen a significant advance in the ability to generate coherent radiation at ever shorter wavelengths now extending throughout the ultraviolet and into the x-ray region of the electromagnetic spectrum. These are particularly interesting spectral regions for applications in many scientific and technological disciplines. Because the wavelength is short, the radiation can be used to both "see" and "write" patterns of small feature size. Thus one can form high spatial resolution x-ray microscopes and microprobes and can fabricate yet more powerful integrated circuits. The photon energy is particularly interesting as it coincides with the many atomic and molecular transition resonances which pervade this region of the spectrum. The new accessibility of this region, provided both high brightness sources and requisite x-ray optics are available, will permit the utilization of many exciting techniques. Element specific bio-dynamics, site specific photochemical processing, polarization sensitive scattering studies of chiral structures, element specific studies of surface state formation, and dynamical studies of thin film and lattice structure formation are, to name a few, fields which would benefit from the unique capabilities of elemental sensitivity and high space-time resolution. Coherence Requirements An example of an experimental technique which would benefit many of the above cited sciences is that of an x-ray microprobe. As illustrated in figure 1, a Fresnel zone plate might be used to concentrate radiation in a small Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1986627 C6-204 JOURNAL DE PHYSIQUE focal spot area. The radiation could be used to probe, stimulate or scan any of a variety of chemically, physically or biologically interesting systems. The size of the focal region is dependent upon both the spatial and temporal properties of the incident radiation. For spatially coherent radiation a focal spot diameter (waist) of 2.4Ar will be obtained with a zone plate of outer zone width Ar. Resolution, as defined by Rayleigh, would be 1.2Ar. A zone plate of outer zone width of 500 A would give a focal spot diameter of approximately 1200 A. To achieve this diffraction limited focusing it is necessary that the zone plate be perfect to a fraction of a wavelength, and that the radiation emanate from an uncertainty limited phase space characterized by 8-8 = A/2. If the radiation is characterized by a larger phase space, the resulting focal spot will be proportionally larger and the resolution proportionally degraded. The zone plate microprobe also requires a degree of temporal (longitudinal) coherence, albeit modest. In order to avoid blurring of the focal region by chromatic aberration, the radiation must possess a coherence length (distance over which interference effects are significant) Qc = A2/bA, at least as large as the coherence requirements of the zone plate, blA/2, where bl is the number of Fresnel zones. Generally this is a modest requirement: with bl = 500 and A -30 A, one requires Qc lpm. A somewhat more demanding experiment is that of off-axis x-ray microholography, as illustrated in figure 2. In this case the ZP does not form an image in the recording plahe, but rather it gathers the high frequency (large angle) scattered radiation (containing details of the smaller sample features) and directs it back toward the recording medium where it is encoded through interference with a plane or spherical reference wave generated by the nearby diffraction grating. The scattered radiation is thus heterodyned by the reference wave, with a carrier spatial frequency roughly that of the grating, allowing use of a lower resolution but more sensitive recorder (perhaps x-ray film) than would otherwise be possible. Both spatial and temporal coherence requirements are more demanding in the holographic case, requiring spatially coherent illumination over a field wider by some factor, and a temporal coherence length increased by that factor squared, e.g. if the grating extends laterally to a distance of five ZP radii, then the temporal coherence must be increased by a factor of twenty-five. Thus one would require full spatial coherence and a longitudinal coherence of 20 pm. Radiation Sources The generation of partially coherent radiation, combined with requisite spatial and temporal filtering, can be achieved in several ways. Figures 3-5 illustrate an atomic laser, a magnetic undulator, and a laser-produced, hot-dense plasma emitting x-rays into 2s steradians. All three can generate radiation at XW wavelengths, and perhaps it can be said that all are partially coherent certainly all could be used as the source of radiation in figures 1 and 2. The differences are the degree of coherence, determining the amount of spatial and temporal filtering required for a particular application; the average a?d peak power produced; and the shortness of the wavelength and its nearness to the atomic and molecular resonances of interest. Radiative Performance In figures 6-8 we show generated coherent power and spectral brightness, for both average and peak values, and for a variety of spectral widths (coherence lengths). In the estimates of coherent power, only that portion of the radiation within d-8 = A/2 is accepted, such that full spatial coherence would result. In addition, perfect optics are assumed no aberrations, 100% efficiency. The need for several illustrations is due to the wide variety of applications one can envision, some requiring minimal coherence, others requiring substantial coherence. Upon inspection one readily sees that each of the radiation sources has its own advantages. References 1. D.L. Hatthews et al., Phys. Rev. Letters, 54, 110, 1985; M.D. Rosen et al., Phys Rev. Letters, 54, 106, 1985. 2. D.T. Attwood, K-J. Kim, K. Halbach, and H.R. Howells, "Undulators as a Primary Source of Coherent X-rays", paper presented at the International Conference on Insertion Devices for Synchrotron Sources, October 1985; also published as Lawrence Berkeley Laboratory PUB-20569, 1985. 3. Recent (June, 1986) undulator experiments are reported by H. Rarbaek, Brookhaven National Laboratory, Upton. New York. 4. D.W. Phillion, E.H. Campbell et al.. to be published; D.T. Attwood, N.M. Ceglio, E.H. Campbell, J.T. Larson, D.H. Hatthews, and S.L. Lane, "Compression Heasurements in Laser-Driven Implosion Experiments", Laser Interaction and Related Plasma Phenomenon, (Plenum, New York, 1981) eds. H.J. Schwarz. H. Hora, M.J. Lubin, and B. Yaakobi; B. Yaakobi et al., Optics Communications, 33, 196, 1981. 5. Nasif Iskander and Nadine Wang, Optical Society of America, Topical Conference on Short Wavelength Coherent Radiation. Honterey. CA, April 1986. zones Resolution = 1.2 FA = 1.2 Ar D = 4NAr Figure 1. An x-ray microprobe based on use of a Presnel zone plate. Spatially coherent radiation is focused to the smallest possible focal spot, of diameter 2.4Ar. Longitudinal (temporal) coherence equal to N W 2 is required to avoid chromatic defocusing effects, where N is the number of zones. Thus both temporal and spatial coherence are required.

Journal ArticleDOI
TL;DR: In this article, the authors show that a thick, tapered zone plate acts like a thin zone plate for points within its field of view and depth of field, and that the source strength required to image a 20μm-diam source is 100 to 1000 times less than that needed with an equivalent pinh...
Abstract: Zone‐plate coded imaging techniques are routinely used to image nonpenetrating emissions from laser fusion targets. Only highly penetrating radiations like 14‐MeV neutrons will escape the dense compressed core region of future targets to provide information about the burn region. A zone plate for 14‐MeV neutrons must be several centimeters thick to produce adequate modulation in the coded image. Computer modeling of zone‐plate systems show that a thick, tapered zone plate acts like a thin zone plate for points within its field of view and depth of field. Equations developed for thin zone‐plate systems that describe quantities such as planar and tomographic resolution may be applied to thick zone‐plate systems. System simulations of a 100‐zone, 5‐cm‐thick zone plate with 5‐μm outer zone width constructed of alternating layers of gold and aluminum produce images with 10‐μm resolution. The source strength required to image a 20‐μm‐diam source is 100 to 1000 times less than that needed with an equivalent pinh...

Book ChapterDOI
01 Jan 1986
TL;DR: In this paper, the imaging properties of amplitude and phase zone plates were considered, on the assumption that the zone boundaries were correctly positioned, and the properties were modified for realizable zone plates, since the boundaries cannot be positioned with arbitrary accuracy.
Abstract: In the previous chapter the imaging properties of amplitude and phase zone plates were considered, on the assumption that the zone boundaries were correctly positioned. These properties will be modified for realizable zone plates, since the boundaries cannot be positioned with arbitrary accuracy. In particular, the intensity in each of the predicted foci will, in general, be decreased, the point spread functions will be changed, and further foci may be obtained. A normally less important modification may be to the positions of the foci. In addition, amplitude zone plates for soft X rays are normally made on a supporting substrate, causing the open zones to be partially absorbing, while the closed zones may not be thick enough to be totally absorbing. By placing limits on the effects of these changes, for example by stipulating that diffraction-limited imaging is required, manufacturing tolerances can be obtained. The types of manufacturing error, and the corresponding tolerances, depend on the method of making the zone plates. Some methods for manufacturing amplitude zone plates will be discussed later in this chapter, while in this section tolerances will be established. The manufacture of phase zone plates will be discussed in Chapter 11, since the optical properties of most materials in the soft X-ray region are not yet known with sufficient accuracy to enable them to be designed and made with any confidence.

Patent
30 Apr 1986
TL;DR: In this article, a Fresnel zone plate is formed by the concentric formation of many annular grooves in that surface of a light emitting element made of compound semiconductor which is closer to the light emitting part.
Abstract: PURPOSE:To effectively collect light from the light emitting part without the use of spherical lenses difficult in optical-axis alignment by a method wherein a Fresnel zone plate is formed on the surface of a light emitting element. CONSTITUTION:The Fresnel zone plate 14 is formed by the concentric formation of many annular grooves 13 in that surface of a light emitting element 11 made of compound semiconductor which is closer to the light emitting part 12. The center of this plate 14 is coaxial with that of the light emitting part 12, and the plate 14 shares the optical axis with this part 12. Therefore, the emitted light of the part 12 is collected by the plate 14 and becomes a light flux running along the optical axis of the plate 14.

Journal ArticleDOI
TL;DR: An improvement for holographic nondestructive testing in the field of information processing makes use of an optically generated zone plate for obtaining an interferometric hologram of an object suffering a deformation that allows quick data acquisition and can be used outside laboratory conditions.
Abstract: An improvement for holographic nondestructive testing in the field of information processing is proposed. It makes use of an optically generated zone plate for obtaining an interferometric hologram of an object suffering a deformation. This allows quick data acquisition and can be used outside laboratory conditions. Experimental results are discussed, and a brief mathematical analysis from the point of view of Fourier optics is also given.

Proceedings ArticleDOI
10 Sep 1986
TL;DR: In this article, the authors used monochromatized synchrotron radiation as its source, and a collimated portion of this source was focused with a Fresnel zone plate to a submicron spot, across which the specimen was scanned under computer control.
Abstract: In scanning soft X‐ray microscopy a quantitative map of specimen absorptivity is obtained. Sharp changes in the transmission spectrum at absorption edges provide contrast and are the basis for elemental analysis by comparison of images taken at differing wavelengths. We have developed an instrument that uses monochromatized synchrotron radiation as its source. A collimated portion of this source is focused with a Fresnel zone plate to a submicron spot, across which the specimen is scanned under computer control. To illustrate the microscope’s capabilities, we have imaged whole cultured cells in a fixed but wet and unstained state, and measured the distribution of calcium in thin sections of human bone tissue.

Proceedings ArticleDOI
13 Oct 1986
TL;DR: In this article, the axial detector (AX-D) is described as a new detector configuration that is planned to take maximum advantage of the optical-spectral properties of zone plates.
Abstract: Zone plate optical-spectral properties are described and key parameters are tabulated. Several arrangements are given for zone plate optical sensors, and the advantages of zone plate optical elements are listed. The axial detector (AX-D) is described as a new detector configuration that is planned to take maximum advantage of the optical-spectral properties of zone plates.

Patent
27 Mar 1986
TL;DR: In this paper, a transmission type Fresnel zone plate was mounted on an X-ray beam optical axis between an Xray source and a mask to increase the intensity of projecting X-rays, and to enable uniform irradiation in an irradiating surface.
Abstract: PURPOSE:To increase the intensity of projecting X-rays, and to enable uniform irradiation in an irradiating surface by mounting a transmission type Fresnel zone plate on an X-ray beam optical axis between an X-ray source for generating input X-ray beams and a mask. CONSTITUTION:X-ray beams diffused and propagated from an X-ray source 1 for laser plasma, etc. are changed into approximately parallel X-ray beams by a Fresnel zone plate 4 inserted and fitted onto an optical axis between the X-ray source 1 and a mask 2, and projected to the surfaces of the mask 2 and a wafer 3, on which a photosensitive resin is applied, approximately vertically. Accordingly, X-ray beams are condensed by the Fresnel zone plate 4 and utilized, thus increasing the luminance of X-rays on an irradiating surface.

Journal ArticleDOI
TL;DR: In this paper, the dispersive characteristics of a Ta film one-dimensional Fresnel zone plate (FZP) measured using synchrotron radiation as a light source were investigated.
Abstract: This paper presents the dispersive characteristics of a Ta film one-dimensional Fresnel zone plate (FZP) measured using synchrotron radiation as a light source. Spectral spatial distributions of the FZP linear monochromator output beam are recorded on an X-ray film. The observed distributions are well explained by the FZP's chromatic aberration. The spectral bandwidth of the monochromator output beam decreases proportional to the slit width and saturates at approximately the value limited by the size of the focused image of the synchrotron radiation source.