A Method Of Interfacing A Transmission Electron Microscope (Tem) With An Automatic Image Analysis System (AIA)

Abstract

To interface a TEM with an AIA, I replaced the 70mm. camera mounting on the TEM with a fixture incorporating a fluorescent screen and a leaded glass X-ray shield. The phosphor I chose for the screen, “P-12”, is highly efficient and exhibits a spectral peak at the same wavelength as the television tube selected for the job. This tube is a Type 4532 silicon-intensified target (SIT) tube supplied by COHU, Inc. as part of their Type 4250 low-light-level television camera (LLLTV). The composite video signal from this camera is transmitted by cable to the AIA system where it is processed and displayed on a monitor along with information regarding the processing. A second cable returns this processed video signal to the TEM where another monitor allows the microscope operator to see the results. The processing of the signal includes detection of features in the field of view using a grey-level threshold set by the AIA operator, and selection of the desired features thus detected by means of size and shape parameters also supplied by the operator.