In the neighborhood of each connecting region of a panel substrate, tape automated bonding substrates, and a flexible substrate, marks for a visual inspection are provided at a preset distance apart from the connecting region. The method includes producing a secure document having printed information and coded data thereon, the coded data including a unique identifier indicative of the secure document. A purge gas flow is provided proximate to an optical element to prevent a vapor from the exposed photoresist material from coming into contact with the optical element.