The 552 Dual Beam Oscilloscope was first proposed in 1960 to fit the needs of the medical market. One of the features would be a slave CRT used for photography. The 552 was never produced but we have some documents with historically significance.
This sketch of the 552 is interesting with three plug-ins but with the CRT in the upper right corner instead of the typical upper left corner.
This set of documents contains letters (with one on an official Inter-Office Communications (IOC) form) between the field and factory. What is interesting are eight documents where different individuals gave their "comments, opinions, and reactions to this proposed instrument". These forms give some insight into the new product concept process used in the early 1960s. Click on the image to view the PDF.