摘要 |
Manufacture of an optical lens comprises using a mould comprising two shells separated by an annular joint of a synthetic elastomer material shaped to co-operate with the edges of the shells and designed to be compressed elastically as the shells are forced together. The join has hole(s) for filling the mould cavity with polymerizable material after a mechanical pressure has been applied to the two shells and before it is released. The procedure uses a mould (1) comprising two shells (2, 3) separated by an annular joint (4) of a synthetic elastomer material shaped to co-operate with the edges of the shells and designed to be compressed elastically as the shells are forced together. The joint, which has a modulus of elasticity of 0.8 - 1.3 MPa at 100 per cent and a rupture strength of some 3 - 7 MPa, has at least one hole (19) for filling the mould cavity with the polymerizable material after a mechanical pressure has been applied to the two shells and before it is released. |