Manufacturing
The Manufacturing section allows you to consider and anticipate mechanical constraints coming from the surface's manufacture.
Sewing
Sometimes a gap may appear between the elements.
Activating the Sewing option automatically fills any gaps that might appear during construction.
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| Optical surface without sewing - Gaps remain between the elements | Optical surface with sewing - Gaps between the elements are filled |
Drafting
Surfaces generated without drafting induce a manufacturing issue when they are removed from their mold.
Activating the Drafting allows you to take into account mechanical constraints and ensure an accurate manufacture.
Drafting can be done by length or by angle.
Draft Length
When selecting Draft length, the value to define determines the size of the sewing surface created between two adjacent elements.
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| Rectangular feature with a drafting of 2mm | Circular feature with a drafting of 2mm |
Draft Angle
When selecting Draft angle, the value to define determines the angle to create between the demolding axis and the facet.
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| Draft angle | Demolding axis | Impact of drafting angle on an optical surface |
When the Draft angle is needed on an element of the grid, the Draft angle is applied on the entire row and the entire column to which the element belongs.
_opd_optical_surface_draft_angle_03.png)
_opd_optical_surface_draft_angle_02.png)
Draft Angle Limitations
- The Draft Angle is not compatible with:
- Optical Surface with a Stripes grid
- Optical Surface with a Circular grid and a radial shift
- The Draft angle on faces sewing at corner of the elements can be lower.
_opd_optical_surface_draft_angle_03.png)
- The Draft angle is not applied on lens borders and central closing borders.
_opd_optical_surface_draft_angle_04.png)
_opd_optical_surface_sewing_01.png)
_opd_optical_surface_sewing_02.png)
_opd_optical_surface_draft_length_01.png)
_opd_optical_surface_draft_length_02.png)
_opd_optical_surface_draft_angle_01.png)
_opd_optical_surface_draft_angle_02.png)
_opd_optical_surface_draft_angle_01.png)