| 摘要 |
A tool(1) with forming surface(3) is pressed against a substrate with a preformed area(16) and heated above its glass transition temperature. Contact is initially made at the central area(11) so that an increasing gap width(WO) created between the tool forming surface and the substrate surface extends to the tool and substrate edge(2,14). Continuous pressure application increases the area of contact between tool forming area and substrate until both are fully in contact with each other and the finished component has the same shape as the tool. - When producing a convex component(20) using a concave tool(1), both radii are negative and the radius(r1) of the concave tool surface(3) in absolute terms is greater than that of the radius(r2) of the substrate preformed area(16) to be formed and therefore r1 at least r2. When forming a concave optical component the radius(r2) of the substrate(10) is greater than the radius(r1) of the convex tool surface and as both are positive r1 at least r2. The gap width(WO) increases constantly towards the tool and substrate edge(2,14) and allows gas bubbles to escape. An elongated recess on the tool and/or substrate outside the forming area is linked to the gap to assist with gas exclusion. Gap enlargement is parallel to an upper surface of the tool(1). The gap may be annular and increases in width radially from the central area(11). No transverse spreading of the substrate occurs during the forming stage. Tool forming surfaces and the preformed area of the substrate may be raised sections or recesses on the tool or substrate surface. Preformed areas of substrates may be spherical and the tool aspherical so that the preformed substrate area can be formed into a spherical optical component. Several optical components may be produced simultaneously and then separated into individual components by cutting through from the base of the substrate. Optical structures formed on the finished component may include diffractive and/or refractive features. An INDEPENDENT CLAIM is included for the process equipment which comprises a tool with curved forming areas and a substrate with curved preformed areas. When pressed together and heated the tool surface and substrate contact initially at the center and form an enlarging gap which extends to the tool or substrate edge. |
