Enhancing Visibility Of "Transparent" Alignment Marks
Original Publication Date: 1979-Sep-01
Included in the Prior Art Database: 2005-Feb-20
Many industrial products are created by multi-step processes whereby different geometric patterns are designed to accurately overlay an original "first" pattern on a substrate. Generally, such pattern forming materials are inherently visible so that registration of one pattern relative to another can be readily seen and controlled. However, difficulties are experienced in registering products which are comprised of transparent or semi-transparent coatings patterned onto substrate carriers which are themselves transparent. Examples of this structure are devices such as transparent data input tablets mounted on the face plate of a display device, such as a cathode ray tube or gas discharge panel.