Process of dosing a starting material for optical lenses
View Patent ↗A process of dosing a starting material (SM) for optical lenses, into a female mold half ( 2 ), comprises the steps of: positioning a dosing tip ( 1 ) at a start position (P 2 ) above the female mold half ( 2 ) and close to the edge of or laterally outside that portion ( 20 ) defining the lens-shaping surface, creating a continuous flow of starting material (SM) through the dosing tip ( 1 ) into the female mold half ( 2 ), moving the dosing tip ( 1 ) from the start position (P 2 ) towards an end position (P 3 ) in the region of the center of the female mold half ( 2 ) once the starting material (SM) has contacted the surface ( 21 ) of the female mold half ( 2 ) with the dosing tip ( 1 ) being in the start position (P 2 ), wherein the continuous flow of starting material (SM) through the dosing tip ( 1 ) and the movement of the dosing tip ( 1 ) from the start position (P 2 ) to its end position (P 3 ) are controlled such, that a continuous bead (B) of starting material (SM) is deposited on the surface ( 21 ) of the female mold half ( 2 ) and that the essential part of the overall volume of starting material (SM) dosed into the female mold half ( 2 ) is deposited within the female mold half ( 2 ) with the dosing tip ( 1 ) being in the end position (P 3 ).
1. Process of dosing a starting material for optical lenses into a female mould half having a concave surface, the process comprising the steps of:
positioning a dosing tip at a start position above the female mould half and close to the edge of or laterally outside that portion ( 20 ) defining the lens-shaping surface,
creating a continuous flow of starting material through the dosing tip into the female mould half,
moving the dosing tip from the start position towards an end position in the region of the centre of the female mould half once the starting material has contacted the surface of the female mould half with the dosing tip being in the start position, wherein the continuous flow of starting material through the dosing tip and the movement of the dosing tip from the start position to its end position are controlled such, that a continuous bead of starting material is deposited on the surface of the female mould half and higher than 50% of the overall volume of starting material dosed into the female mould half is deposited within the female mould half with the dosing tip being in the end position.
2. Process according to claim 1 , wherein the start position of the dosing tip is located above the concave surface of the female mould half laterally outside the lens-shaping portion.
3. Process according to claim 1 , wherein the flow of starting material through the dosing tip is constant and the movement of the dosing tip from the start position to the end position is controlled such that a continuous bead or film of starting material is deposited on the surface of the female mould half.
4. Process according to claim 1 , wherein the flow of starting material through the dosing tip is varying and the movement of the dosing tip from its start position to its end position is adapted to the varying flow of starting material through the dosing tip such that a continuous bead of starting material is deposited on the surface of the female mould half.
5. Process according to any one of the preceding claims, wherein the flow of starting material through the dosing tip and the movement of the dosing tip from its start position towards its end position are controlled such that only a thin but continuous film of starting material is deposited on the surface of the female mould half until the dosing tip has reached the end position.