Free space microscope digitizing aid

摘要

There is disclosed an inspection system which allows the visual inspection of an item and the automatic recordation of the position of a defect or other inspection characteristic in the plane of inspection. In the visual inspection of an electronic circuit card, the card is inserted into a holder which maintains the card in a reference plane which is fixed relative to a plurality of sonic emitters. A microscope or other viewing device is fixed in a predetermined position on a support structure and includes cross hairs or other indicia to allow the visual identification of a particular point on an item that is to be visually inspected. A plurality of sonic receivers are coupled in predetermined positions on the support structure to receive sonic energy generated by the emitters. A manual control is coupled to initiate the production of sonic energy from the emitters while a digitizer and programmed microprocessor are coupled to receive signals from the sonic receivers in order to make a calculation of the position of each point visually observed on the inspection item. A complete history of the identified characteristics of an inspected item can be identified and stored with only simple movement of an item in the holder beneath the microscope to allow fast and easy visual inspection of a given item.