Measuring the angles and pyramidal error of high-precision prisms m#Cp.|>kP4  
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High-precision prisms, having maximum angle tolerances hRP0Djc  
of 1 to 3 arcsec, find increasing application in optical metrology. -Je+7#P1  
Reported interferometric techniques for measuring ]n+:lsiV  
the wedge angles of such prisms achieve a precision of up *)`:Nm~y  
to 0.1 arcsec ~Ref. 1!, while noninterferometric techniques o}T]f(>}  
have a precision of up to 2 arcsec ~Ref. 2!. Reported noninterferometric m2;%|QE(  
methods have made use of goniometers,2 fqcyCu7Ep  
spectrometers,3 master prisms,4,5 and collimators.6 However, &HWH
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in the literature there are few reported methods for \sk,3b-&'  
measuring the pyramidal error, and the majority rely on 1yhx)m;f  
visual observation,2,7,8 by which it is only possible to measure m>iuy:ti  
pyramidal errors to the order of 1 arcmin ~Ref. 8!. R{T4AZ@,'  
In the new arrangement presented here, one can measure pH4i6B*5  
the prism angle and the pyramidal error separately or in !n7?w@2a'  
combination. This is possible because the measurements !%Ak15o  
are made simultaneously but with different techniques.