Replace the first sentence of the third paragraph with the following: This standard applies to medical IMAGE DISPLAY SYSTEMS, which can display image information on greyscale and colour IMAGE DISPLAY SYSTEMS. Add, at the end of the third paragraph, the following new sentence: Handheld IMAGE DISPLAY SYSTEMS might require additional or modified versions of the procedures described in this document. Replace the fourth paragraph with the following: It is not in the scope of this standard to define either the requirements of acceptance and constancy tests or the frequencies of constancy tests.