摘要:

Moments and the first order probability density function of the intensity in a speckle pattern are considered as a function of the spectral bandwidth of the incident light. It is shown that the standard deviation of the intensity generally depends on the surface roughness of the diffuser, and on the position of measurement in the far field. Numerical results are given for a diffuser with a Gaussian distribution of surface height limited by a circular aperture. Exact and approximate forms of the probability density function are discussed. The analysis applies when the fluctuations in optical path are greater than the maximum wavelength incident.

ISSN:0030-3909    

DOI:10.1080/713818852

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The influence of the population inversion cross section profile on the dynamics of the single-mode solid-state laser is investigated. Such a profile leads to spatial inhomogeneity of the laser medium dielectric permeability (lenslike medium). The laser medium parameters are functions of the laser field amplitude. Under certain conditions the laser field amplitude and the population inversion start to oscillate simultaneously due to self-Q-switching in the lenslike medium and pulsations appear in the laser output.

ISSN:0030-3909    

DOI:10.1080/713818850

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713818853

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

In der Arbeit wird untersucht, welche Meßgenauigkeit bei der Anwendung eines Ringinterferometers zur Messung kleiner optischer Drehungen erreicht werden kann. Dazu muß der Intensitätsschwächungsfaktor des Resonators bekannt sein. Es wird eine Methode vorgeschlagen, mit der der Intensitätsschwächungsfaktor experimentell bestimmt werden kann. Es zeigt sich, daß die Anwendung des Ringinterferometers eine wesentliche Erhöhung der Meßgenauigkeit gegenüber anderen Meßmethoden bringt, falls der optische Drehwinkel der Probe kleiner als etwa 1° ist und eine durch den Intensitätsschwächungsfaktor bedingte Grenze nicht unterschreitet.

ISSN:0030-3909    

DOI:10.1080/713818845

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Expressions have been derived for the transfer function of a circular aperture suffering from astigmatism and operating in non-uniform illumination. The intensity distribution considered is given ast(x, y) = 1 -A(x2+y2). The modifications in the optical transfer function by changingA, the apodization parameter, has been shown graphically.

ISSN:0030-3909    

DOI:10.1080/713818848

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

On étudie la mise en oeuvre de la mesure de la fonction de transfert par la méthode dite du ‘bord de plage’, qui consiste à analyser l'image d'une fente lumineuse par un couteau d'amplitude puis à traiter a posteriori le signal par un ordinateur en utilisant les différentes approximations proposées par Tatian. On mesure sur deux objectifs la fonction de transfert optique par cette méthode. On compare les résultats à la fonction de transfert de modulation obtenue par une méthode analogique.

ISSN:0030-3909    

DOI:10.1080/713818849

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The effects of condenser transmission characteristics upon the performance of partially coherent systems have been investigated. It has been shown that the transmittance of the condenser aperture affects the coherence conditions prevailing upon the object plane and modifies the image forming properties of the system. Two different types of irradiance distribution functions have been assumed, in the first type the irradiance is maximum at the centre and tapers off towards the edges of the aperture, the reverse being true for the second type. Their influence upon the spatial frequency response and the edge response of the system has been investigated. The effect of the condenser size and transmission upon the two-point resolution of the system has also been examined.

ISSN:0030-3909    

DOI:10.1080/713818847

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Expressions are derived for the unaberrated complex scattering potential of thin (< 100 Å) phase objects in terms of the sum and difference of the image intensities formed in successive experiments with complementary half-plane apertures inserted in the back-focal plane of the objective lens of an electron microscope.

ISSN:0030-3909    

DOI:10.1080/713818844

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/713818854

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

ISSN:0030-3909    

DOI:10.1080/716099342a

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor