SMPTE (Society for Motion Picture and Television Engineers) is an international standards development organization. SMPTE has specified several test patterns, one of which is used to evaluate the performance of diagnostic displays. The SMPTE test pattern has been largely superseded by the AAPM TG18 test patterns.
The SMPTE home page is http://www.smpte.org.
An example of the SMPTE test pattern for medical diagnostic imaging is available on Wikipedia at: http://en.wikipedia.org/wiki/Image:SMPTE_RP-133_small.png