摘要:

An x‐ray spectrometer was designed with the first crystal mounted on an arm supported by the frame of the spectrometer, and with the second crystal mounted on the central table of the instrument, whose position is read from a precision circle. The ionization chamber (of 28 cc capacity, filled with krypton) is on an arm whose position is read by a second precision circle. The instrument was built by the Societe Genevoise de Physique.The first crystal was adjusted to throw the K&agr;1line of molybdenum over the main axis of the spectrometer, and measurements were made with the second crystal in the (1, −1), (1, +1), (1, −4) and (1, +4) positions (Allison's notation). The reflection maxima from calcite (corrected to 18° C) occur at &thgr;1=6°42′35.″5 and &thgr;4=27°51′33.″0 with a probable error of 0.″25 due chiefly to errors in reading the circle. Using an apparent grating space for the first order of 3.02904A at 18° C, we get &lgr;=707.830±.002 mA. Larsson obtained 707.831±.003 mA using Siegbahn's photographic method. Comparison of &thgr;1and &thgr;4gives for the index of refraction in calcite, 1 −&mgr;=(2.10±.15)×10−6, as compared with Hatley's value of (2.04±.09)×10−6.

ISSN:0034-6748    

DOI:10.1063/1.1748803

出版商:AIP    

年代:1931

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1748804

出版商:AIP    

年代:1931

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1748805

出版商:AIP    

年代:1931

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1748806

出版商:AIP    

年代:1931

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1748807

出版商:AIP    

年代:1931

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1748808

出版商:AIP    

年代:1931

数据来源: AIP

摘要:

Methods are described for the measurement of the lateral chromatic aberration and distortion of microscope objectives and eyepieces. Measurements have been made on 20 apochromatic microscope objectives of 4 different makes, and on 10 compensating eyepieces of 2 different makes. The results show that the compensating eyepieces in general do not entirely compensate the chromatic aberration of the objectives and that the complete microscope system is usually undercorrected. The bearing of this on the performance of the system in photomicrographic work by a three color process and in the direct visual observation of objects is considered in detail.

ISSN:0034-6748    

DOI:10.1063/1.1748809

出版商:AIP    

年代:1931

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1748810

出版商:AIP    

年代:1931

数据来源: AIP