Method of producing an optical or electronic module provided with a plastic casing

A component(1) is encapsulated in a plastic material(40) which forms a housing(4). The position of the component is recorded before or after encapsulation by direct measurement. The component is then aligned relative to a tool(30), the alignment being dependent on the recorded position of the component. An area of the plastic is then removed by the tool between the outside of the housing and an active area(11) of the component so that the latter area is exposed to the environment. Direct measurement of the component position can be made by an image recognition system before or after encapsulation, in the later case the plastic being transparent. Direct measurement of component position after encapsulation can also be achieved with non-transparent plastic using ultrasonic or X-ray equipment(20). Electrical connections(5) to the component are made before encapsulation, the connections being in a housing area remote from that which is subsequently removed. Electrical connections are made by bonded wires. The component may be mounted on a support before encapsulation. A typical support comprises a lead frame(3) with flat supporting area(32) and several contact areas(31) at the frame edge. Removal of plastic can be effected with a milling tool or a laser beam. Encapsulation involves either casting or pressing of one or more plastics around the component. The housing opening created by removal of plastic has an axis of symmetry coincident with the component axis.