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The result of a measurement of the modulation transfer function is only useful as long as it is accompanied by a complete description of all relevant measuring conditions involved. For this reason it is necessary to file a full description of the relevant measuring conditions together with the results. In earlier times some of our results were rendered useless because some of the relevant measuring conditions were accidentally not written down and were forgotten. This was mainly due to the lack of concensus about which measuring conditions had to be filed together with the result of a measurement. One way to secure uniform and complete archiving of measuring conditions and results is to automate the data handling. An attendent advantage of automation of data handling is that it does away with the time-consuming correction of rough measuring results. The automation of the data handling was accomplished with rather cheap desktop computers, which were powerfull enough, however, to allow us to automate the measurement as well. After automation of the data handling we started with automatic collection of rough measurement data. Step by step we extended the automation by letting the desktop computer control more and more of the measuring set-up. At present the desktop computer controls all the electrical and most of the mechanical measuring conditions. Further it controls and reads the MTF measuring instrument. Focussing and orientation optimization can be fully automatic, semi-automatic or completely manual. MTF measuring results can be collected automatically but they can also be typed in by hand. Due to the automation we are able to implement proper archival of measuring results together with all necessary measuring conditions. The improved measuring efficiency made it possible to increase the number of routine measurements done in the same time period by an order of magnitude. To our surprise the measuring accuracy also improved by a factor of two. This was due to the much better reproducibility of the automatic optimization, which resulted in better reproducibility of the measurement result. Another advantage of the automation is that the programs that control the data handling and the automatic measurement are "user friendly". They guide the operator through the measuring procedure using information from earlier measurements of equivalent test specimens. This makes it possible to let routine measurements be done by much less skilled assistants. It also removes much of the tedious routine labour normally involved in MTF measurements. It can be concluded that automation of MTF measurements as described in the foregoing enhances the usefulness of MTF results as well as reducing the cost of MTF measurements.
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