Showing papers in "Journal of Modern Optics in 1984"
TL;DR: The Fokker-Planck Equation: Methods of Solution and Applications as discussed by the authors is a well-known method for solution and application in the field of Optica-Acta.
Abstract: (1984). The Fokker-Planck Equation: Methods of Solution and Applications. Optica Acta: International Journal of Optics: Vol. 31, No. 11, pp. 1206-1207.
1,541 citations
TL;DR: The Handbook of Stochastic Methods for Physics, Chemistry and the Natural Sciences as mentioned in this paper is a popular reference book for physics, chemistry and the natural sciences that is used in many applications.
Abstract: (1984). Handbook of Stochastic Methods for Physics, Chemistry and the Natural Sciences. Optica Acta: International Journal of Optics: Vol. 31, No. 9, pp. 977-978.
1,475 citations
TL;DR: Polarization holographic recording, based on photoinducing optical anisotropy in the recording material, is examined in this paper, where the properties (diffraction efficiency and selectivity) are discussed for two t
Abstract: Polarization holographic recording, based on photoinducing optical anisotropy in the recording material, is examined. The properties (diffraction efficiency and selectivity) are discussed for two t...
318 citations
TL;DR: In this paper, Grum et al. presented an overview of the latest advances in Radiometry and Photometry for the detection and assessment of Dental Caries and Optical Radiation.
Abstract: Microwave Radiometric Detection of Oil SlicksRadiometry and the Detection of Optical RadiationOptical Systems Design Detection EssentialsOptoelectronic Workshops 7: Advanced Technology for Radiometry and the Detection of Optical RadiationStudies of Radio Frequency Interference Detection Methods in Microwave RadiometryPassive Infrared DetectionAdvances in Radiometry ResearchDetection and Assessment of Dental CariesMicrowave and Millimeterwave Remote Sensing for Security ApplicationsNon-Imaging Microwave and Millimetre-Wave Sensors for Concealed Object DetectionIntroduction to Radiometry and Photometry, Second EditionOptical Radiation Measurements: Grum, F. C., Becherer, R. RadiometryMicrowave Radiometric Studies in Relation to Mine DetectionMicrowave Radiometry and Remote Sensing of the Earth's Surface and AtmosphereMILLIMETER WAVE RADIOMETRIC DETECTION OF TARGETS OBSCURED BY FOLIAGE.Applied Photometry, Radiometry, and Measurements of Optical LossesPassive Standoff Detection of Chemical Vapors by Differential FTIR RadiometryClinical Application of Microwave Radiometry Techniques in the Detection of CancerPhotometry, Radiometry, and Measurements of Optical LossesRadiometryIce/frost Detection Using Millimeter Wave RadiometryFeasibility Study of Radiometry for Airborne Detection of Aviation HazardsEM Detection of Concealed TargetsLaser Photothermal Radiometry for the Detection of Early Enamel DemineralizationRadio Frequency Radiometry for the Remote Airborne Detection of Small Forest FirDetection and Characterization of Nuclear CloudsAn Application of Pattern Recognition to Radiometric Target DetectionTheory of Broadband Autocorrrelation Radiometry for Spectral Line DetectionInfrared Detectors and SystemsRadiometry Detection of Acoustic SignalsDetection of Greenbug Infestation Using Ground-based RadiometryRadiometry and the Detection of Optical RadiationW-band Radiometry for the Non-invasive Investigation of MaterialsHuman Presence Detection Using Millimeter-wave RadiometryRadiometry for Low Target DetectionUse of Airborne Microwave Radiometry for the Detection and Investigation of Oil Slicks at SeaFeasibility Study of Radiometry for Airborne Detection of Aviation HazardsIntroduction to Radiometry and PhotometryRadio Frequency Interference Characterization and Detection in L-band Microwave RadiometryDetection of Abandoned Underground Coal Mines by Geophysical Methods
213 citations
TL;DR: In this article, a model in which the array of scatterers is represented by a Γ -lorentzian cross-section fluctuation is proposed, and the autocorrelation function and moments of the detected intensity for radiation of arbitrary beamwidth and wavefront curvature are derived.
Abstract: The independent-scatterer K -distribution model, which has been introduced to describe a variety of scattering situations, is extended to include the effects of correlation between scatterers and finite illumination size. A model in which the array of scatterers is represented by a Γ -lorentzian cross-section fluctuation is proposed. In the appropriate limits this reduces to the independent K -distribution model. Following scattering by the Γ -lorentzian surface, the autocorrelation function and moments of the detected intensity for radiation of arbitrary beamwidth and wavefront curvature are derived. The results are compared with the predictions of the independent K -distribution model and the implications of the differences, which reflect the fact that the independent model cannot represent spatial averaging over the correlations within the surface, are discussed.
123 citations
TL;DR: In this paper, the dynamic response of the inversion in a two-level atom to single-mode squeezed states of the radiation field is examined and an increase or decrease in the collapse time is demonstrated.
Abstract: The dynamic response of the inversion in a two-level atom to single-mode squeezed states of the radiation field is examined. Depending on the direction of squeezing, an increase or decrease in the collapse time is demonstrated. A number of additional departures from the response of the atom to a coherent field are noted. In particular, for certain squeezed states the response of the atom is similar to that expected for chaotic radiation.
99 citations
TL;DR: The imaging properties of two types of modified Fresnel zone plate are calculated and compared with those of the equivalent normal zone plate, with particular reference to their use in soft X-ray microscopy as mentioned in this paper.
Abstract: The imaging properties of two types of modified Fresnel zone plate are calculated and compared with those of the equivalent normal zone plate, with particular reference to their use in soft X-ray microscopy. The modifications considered are (1) central obstruction of the zone plates, which improves the resolving power but also leads to loss in efficiency and to a higher fraction of the energy in the outer parts of the diffraction pattern; and (2) a central zone plate with first-order focal length ƒ surrounded by outer zones with third-order focal length ƒ. This gives improved resolution and higher focused energy, but a smaller depth of focus and increased background.
90 citations
TL;DR: In this article, the quantum statistics of linear and nonlinear optical Phenomena are presented. But they do not consider the non-linear optical properties of the optical components of the system.
Abstract: (1984). Quantum Statistics of Linear and Nonlinear Optical Phenomena. Optica Acta: International Journal of Optics: Vol. 31, No. 8, pp. 847-847.
89 citations
TL;DR: In this paper, light scattering in solids is studied in the context of light-scattering in Solids IV, and the authors propose a light scattering algorithm for solids.
Abstract: (1984). Light Scattering in Solids IV. Optica Acta: International Journal of Optics: Vol. 31, No. 11, pp. 1210-1210.
81 citations
TL;DR: In this article, the properties of a linear optical amplifier or attenuator in which the input light is coupled to a collection of non-saturable atoms are derived for arbitrary input statistics.
Abstract: The properties of a linear optical amplifier or attenuator in which the input light is coupled to a collection of non-saturable atoms are considered. The photon-number factorial moments and probability distribution of the amplifier output are derived for arbitrary input statistics. Relations are obtained between the output and input variances in photon number, phase-angle cosine, and electric-field magnitude. The effects of amplification and attenuation on signal-to-noise ratio are obtained for both direct and homodyne detection. Particular attention is paid to the extents to which the non-classical properties of photon antibunching and squeezing are preserved by amplification and attenuation. It is found that both properties can at best survive only twofold intensity amplification.
78 citations
TL;DR: In this article, the 3D point spread functions and optical transfer functions (OTF) are associated with different pupil functions of the imaging system, which are used to obtain information on the structure of an object in the direction perpendicular to the image plane.
Abstract: In many applications such as three-dimensional (3-D) data acquisition, the scanning of 3-D objects or 3-D display, it is necessary to understand how an imaging system can be used to obtain information on the structure of an object in the direction perpendicular to the image plane, i.e. depth information. In certain cases the formation of a 3-D image can be described by a theory based on optical transfer functions (OTF): the image intensity distribution is given by the 3-D convolution of the object and a 3-D point spread function (PSF); equivalently, in 3-D Fourier space the image spectrum is the product of the object spectrum and a 3-D OTF. This paper investigates the 3-D PSFs and OTFs that are associated with different pupil functions of the imaging system.
TL;DR: In this paper, the mutual intensity function is conveniently replaced by the ambiguity function or the Wigner distribution function, which allows us to treat optical systems under partially coherent illumination in a simple fashion.
Abstract: The mutual intensity function is conveniently replaced by the ambiguity function or the Wigner distribution function. This allows us to treat optical systems under partially coherent illumination in a simple fashion. Many optical set-ups can be described on a geometrical basis, as is illustrated with some examples.
TL;DR: In this paper, a generalization of the theory of singular systems has been introduced to deal with gaussian-beam or other illumination or uncertain a priori knowledge of position, and the analysis is applied to determine the amplitude response functions of the scanning optical or acoustic microscope systems.
Abstract: Previous work in this series, in which the theory of singular systems has been used to discuss the problem of diffraction-limited imaging, is generalized to allow the reconstruction of an object over a region with ‘soft’ edges. The generalization is introduced to deal with gaussian-beam or other illumination or uncertain a priori knowledge of position. The solutions are developed in a weighted L2 space. Examples of singular functions and vectors with both gaussian and sine illumination are given. The analysis is applied to determine the amplitude response functions of the scanning optical or acoustic microscope systems proposed by Bertero and Pike in the first paper of the series and it is found that the performance of a scanning microscope of the new type should approach exactly that of a conventional coherent microscope of twice the resolving power. © 1984 Taylor & Francis Group, LLC.
TL;DR: The composition of Chroococcidiopsis cell envelopes was characterized by cytochemical tests for detection of sporopollenin-like compounds, and acid, sulphated and beta-linked polysaccharides, positively charged glycoproteins, lipids and proteins, which were present as very elaborate structures in the envelope of cells from stones and in desiccated cultures.
Abstract: Chroococcidiopsis sp. cells present hypolithically in quartz flints collected in the Negev Desert (Israel) and in wet and desiccated laboratory cultures were examined by light and transmission electron microscopy. The composition of Chroococcidiopsis cell envelopes was characterized by cytochemical tests for detection of sporopollenin-like compounds, and acid, sulphated and beta-linked polysaccharides, positively charged glycoproteins, lipids and proteins. These compounds were present as very elaborate structures in the envelope of cells from stones and in desiccated cultures. An increased envelope thickness is probably useful in the prevention of water loss, although it could cause cell death by reducing exchange with the environment. Isolated living cells that occurred in desiccated cultures might be regarded as resting forms allowing the survival of the cyanobacterium.
TL;DR: This work has derived empirically a simple approximation formula for the entropy of images, and was able to utilize an existing TV optical nonlinear component which performed the analogue calculation of the formula at TV speed.
Abstract: The entropy or average information of an image can be determined approximately from the histogram of the image. The histogram shows the different grey level probabilities in the image. The entropy is useful, for example, for automatic image focusing: as the state of focusing of an image varies, so does its entropy. We present a method for measuring the entropy quite quickly and with reasonable accuracy. Our method is fast for two reasons: we have derived empirically a simple approximation formula for the entropy of images, and we were able to utilize an existing TV optical nonlinear component which performed the analogue calculation of our formula at TV speed. Our method can be applied to real-time focusing of two- or three-dimensional images in a TV system, for example in microscopy.
TL;DR: In this article, a root-finding algorithm for the solution of the eigenvalue equation linked with the theoretical study of lossy lamellar gratings is outlined and the computation time seems to be shorter than required when using a method proposed by Botten et al. (1981).
Abstract: A root-finding algorithm for the solution of the eigenvalue equation linked with the theoretical study of lossy lamellar gratings is outlined. The computation time seems to be shorter than required when using a method proposed by Botten et al. (1981). The agreement is found to be excellent.
TL;DR: In this paper, the evolution of N Rydberg atoms in a high-Q cavity where non-markovian memory effects between atoms and field are important Semiclassical Rabi nutations are examined.
Abstract: We examine the evolution of N Rydberg atoms in a high- Q cavity where non-markovian memory effects between atoms and field are important Semiclassical Rabi nutations are found to be influenced by both quantum collapses and revivals and collective collapses and revivals.
TL;DR: In this paper, the Electronic Excitation Energy Transfer in Condensed Matter (EEETEET) is discussed. But the authors do not discuss the energy transfer in terms of energy transfer.
Abstract: (1984). Electronic Excitation Energy Transfer in Condensed Matter. Optica Acta: International Journal of Optics: Vol. 31, No. 8, pp. 849-849.
TL;DR: In this paper, the recording and replay of volume phase gratings in photorefractive crystals is investigated for both transmission and reflection geometries, and differential equations are derived and solved for a range of parameters including the length of the crystal, the magnitude, spatial distribution and phase angle of the refractive index modulation, the beam ratio at recording, and the angular range at replay.
Abstract: The recording and replay of volume phase gratings in photorefractive crystals is investigated for both transmission and reflection geometries. Differential equations are derived and solved for a range of parameters including the length of the crystal, the magnitude, spatial distribution and phase angle of the refractive index modulation, the beam ratio at recording, and the angular range at replay. The recording process is assumed to reach a steady-state limit before replay with a weak probe beam. Solution of the repaly equations is mainly by numerical integration, although analytic solutions are derived for special cases. It is found that in certain cases the diffraction efficiency can be greatly increased by replaying the hologram at an angle different from the recording angle.
TL;DR: The properties of type I and confocal scanning microscopes are discussed in this article, where it is shown that an enhanced confocal image may be obtained by subtracting the type I from the confocal images, and that the resulting differential contrast image is very sensitive to variations in object height.
Abstract: The properties of type I and confocal scanning microscopes are discussed. It is shown that an enhanced confocal image may be obtained by subtracting the type I from the confocal image. The resulting differential contrast image is found to be very sensitive to variations in object height.
TL;DR: In this paper, a microcomputer-controlled digital radial-shear interferometer was used to test aspheric surfaces with a Twyman-Green interferer, in which the number of fringes in the interferogram can be controlled by varying the shear.
Abstract: It is difficult to test aspheric surfaces with a Twyman-Green interferometer because the interferogram frequently contains too many fringes. A simple way of overcoming this problem is to use a lateral-shearing interferometer, in which case the number of fringes in the interferogram can be controlled by varying the shear. However, this has the drawback that two interferograms with orthogonal directions of shear are required; in addition, the accuracy with which the shape of the surface can be evaluated from measurements on photographs of the fringes is limited. In this paper it is shown how these difficulties can be overcome by using a microcomputer-controlled digital radial-shear interferometer. The values of the phase difference in the interferogram at a matrix of points covering the pupil are processed directly in the same microcomputer to give the actual shape of the surface. Typical results obtained with an off-axis paraboloid are presented.
TL;DR: In this paper, the authors trouve vecteurs, fonctions and valeurs singulieres appropriees a image echantillonnee and un objet continu.
Abstract: On trouve de nouveaux vecteurs, fonctions et valeurs singulieres appropriees a une image echantillonnee et un objet continu. On montre que lorsque le nombre de points image tend vers l'infini, le systeme singulier du probleme discret converge vers le systeme singulier du probleme continu
TL;DR: In this article, the relationship between the lateral and axial periodicities of a propagating, partially coherent wavefield is discussed from two different points of view, and it is shown that the lateral periodicity of the cross-spectral density is the cause of its axial periodicity.
Abstract: The relationship between the lateral and axial periodicities of a propagating, partially coherent wavefield is discussed from two different points of view. First it is shown that the lateral periodicity of the cross-spectral density is the cause of its axial periodicity. The coherent and incoherent limits correspond to the Talbot and Lau effects, respectively. It is then shown that the axial periodicity of fields with restricted spatial spectra also give rise to their lateral periodicity; this is illustrated by some experiments.
TL;DR: In this article, the concept of virtual Fraunhofer diffraction and the treatment of wave aberrations are used to describe in parageometrical terms both the Talbot and the Lau effects.
Abstract: The concept of virtual Fraunhofer diffraction and the treatment of wave aberrations are used to describe in parageometrical terms both the Talbot and the Lau effects. The approach, besides being very simple, can be used to discuss other situations where the two effects may occur.
Journal Article•
TL;DR: In this article, Babinet indique that l'intensite transmise par un ecran est egale a l'interensite reflechie par son ecran complementaire, ce dernier ayant subi une rotation de 90°.
Abstract: Le principe de Babinet indique que l'intensite transmise par un ecran est egale a l'intensite reflechie par son ecran complementaire, ce dernier ayant subi une rotation de 90°. Un ecran autocomplementaire presente la meme configuration apres une rotation de 90° et doit reflechir et transmettre egalement. Un tel ecran doit etre un diviseur de faisceau sans pertes pour toutes les polarisations et dans une grande gamme de longueurs d'onde
TL;DR: In this article, the basic physical mechanisms of hologram formation, as well as the major specific features of Bragg diffraction from anisotropic volume phase holograms recorded in cubic photorefractive crystals, are discussed.
Abstract: The basic physical mechanisms of hologram formation, as well as the major specific features of Bragg diffraction from anisotropic volume phase holograms recorded in cubic photorefractive crystals, are discussed. Special consideration is given to a new dynamic effect of hologram enhancement on recording an interference pattern running with a certain ‘resonance’ speed, the phenomenon underlying a new efficient mechanism of hologram recording, or the ‘long drift length‘ (LDL) mechanism. It is shown that weak light beams can be enhanced and an amplified complex conjugate light wave can be generated in cubic photorefractive crystals in the stationary regime. The maximum amplification is achieved for the shifted LDL hologram in four-wave mixing experiments with positive feedback when two oppositely travelling pump beams polarized orthogonally and at ± 45° to the plane of incidence result in the buildup of the hologram. The main phenomena discussed are illustrated by experimental results obtained in studies of c...
TL;DR: In this paper, a methode for calculing triplets colles de lentilles minces was decrit, which peut etre utilisee for toute aberration primaire and elle est basee sur le concept des aberrations et courbures normalisees and sur un systeme d'elements isometriques precalcules.
Abstract: On decrit une methode pour calculer des triplets colles de lentilles minces. Elle peut etre utilisee pour toute aberration primaire et elle est basee sur le concept des aberrations et courbures normalisees et sur un systeme d'elements isometriques precalcules
TL;DR: In this article, the measurement of suspended particles by quasi-elastic light scattering is described. But this method is not suitable for the case of light scattering in the presence of noisy light.
Abstract: (1984). Measurement of Suspended Particles by Quasi-elastic Light Scattering. Optica Acta: International Journal of Optics: Vol. 31, No. 3, pp. 276-277.