ISSN:0034-6748    

DOI:10.1063/1.1752019

出版商:AIP    

年代:1936

数据来源: AIP

摘要:

The apparatus described serves as an electric drive of a motion picture camera. It permits, in contradistinction to other devices for the same purpose, the independent adjustment of the exposure time and the interval between the exposures. The former can be adjusted between 0.2 and 5 sec., the latter continuously over a range of a factor 5000. Two applications of this apparatus in the field of microcinematography are described, one being the determination of the falling speed of suspended colloid particles in an ultramicroscope, the other being the recording of the growth of etch figures on crystal planes produced by electrolysis.

ISSN:0034-6748    

DOI:10.1063/1.1752033

出版商:AIP    

年代:1936

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752016

出版商:AIP    

年代:1936

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752017

出版商:AIP    

年代:1936

数据来源: AIP

摘要:

Power series are derived with which, given data on the electric field, the focal properties of some common electron lenses can be quickly computed even when the speed of the electrons approaches that of light. The expansion is in powers of the ratio of the P.D. across the lens to the sum of the P.D.'s between its electrodes and the cathode (for electrons) or anode (for positive ions), squares of this ratio being neglected in comparison with unity. As an example the focusing properties of two cylinders almost in contact are calculated.

ISSN:0034-6748    

DOI:10.1063/1.1752018

出版商:AIP    

年代:1936

数据来源: AIP

摘要:

The potential distribution along the axis of two long equal coaxial conducting cylinders has been found to be empirically expressible in terms of the radius and separation of the cylinders. The empirical expression checks well with the single special case (zero separation) which is known to have been solved analytically. The general empirical expression, combined with the theoretical lens equation of Hansen and Webster yields an algebraic formula for lenses of this type directly relating object and image distances to readily measurable quantities.

ISSN:0034-6748    

DOI:10.1063/1.1752020

出版商:AIP    

年代:1936

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752021

出版商:AIP    

年代:1936

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752022

出版商:AIP    

年代:1936

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752023

出版商:AIP    

年代:1936

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752024

出版商:AIP    

年代:1936

数据来源: AIP