a precision placement apparatus comprises an improved probe for aligning a component and a substrate based upon features on the inner surfaces arranged in facing , spaced relationship , prior to assembling the component to the substrate . the probe comprises a dual prism assembly having a first face for viewing the componenet surface and a second face for viewing the substrate surface . the dual prism assembly superposes the images of the surfaces to permit an operator to accurately align the elements . a liquid crystal shutter is mounted onto one face of the dual prism assembly to exclude the image of the corresponding surface and thereby allow the operator to quickly determine the features of the other surface in order to make the appropriate adjustments .