Measuring the angles and pyramidal error of high-precision prisms \gP?uJ  
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High-precision prisms, having maximum angle tolerances IEm?'o:  
of 1 to 3 arcsec, find increasing application in optical metrology. z"6o|]9I  
Reported interferometric techniques for measuring lZwjrU| _  
the wedge angles of such prisms achieve a precision of up :+YHj)mN  
to 0.1 arcsec ~Ref. 1!, while noninterferometric techniques 54z`KX 73  
have a precision of up to 2 arcsec ~Ref. 2!. Reported noninterferometric lz=DGm  
methods have made use of goniometers,2 bAt!S  
spectrometers,3 master prisms,4,5 and collimators.6 However, Rc)]A&J  
in the literature there are few reported methods for b#7nt ?`7p  
measuring the pyramidal error, and the majority rely on 6ud?US(  
visual observation,2,7,8 by which it is only possible to measure ywm"{ U?8  
pyramidal errors to the order of 1 arcmin ~Ref. 8!. 5JOfJ$(n  
In the new arrangement presented here, one can measure ULew ~j  
the prism angle and the pyramidal error separately or in .;?ha'  
combination. This is possible because the measurements lsV>sW4]Z  
are made simultaneously but with different techniques.