Introduction
This process guide applies to the TrilogyTM Aspheric Single Vision lens. It includes the pertinent blank information needed to process the lens. The blank data is summarized below.
TrilogyTM Aspheric Single Vision Product Geometry
| Nominal Base Curve (D) |
Actual Base (1.53)(D) |
Actual Base Radius (mm) |
Sagitta (50mm) |
Back Curve (1.53) |
Diameter (mm) |
Center Thickness (+/- 1.0mm) |
Edge Thickness (+/- 1.0mm) |
Recommended Sphere Power Range |
| 0.50 |
0.62 |
854.84 |
0.370 |
6.25 |
76.00 |
7.0 |
14.5 |
-9.00 to -6.50 |
| 1.25 |
1.34 |
395.52 |
0.790 |
4.25 |
76.00 |
7.0 |
10.0 |
-6.25 to -4.25 |
| 2.25 |
2.35 |
225.53 |
1.390 |
4.25 |
76.00 |
7.5 |
10.0 |
-4.00 to -2.25 |
| 3.00 |
3.09 |
171.52 |
1.832 |
4.25 |
76.00 |
6.5 |
7.5 |
-2.00 to 0.00 |
| 3.50 |
3.50 |
151.43 |
2.080 |
4.25 |
76.00 |
6.5 |
7.5 |
+0.25 to +2.00 |
| 4.25 |
4.17 |
127.10 |
2.483 |
4.25 |
76.00 |
7.5 |
7.5 |
+2.25 to +3.00 |
| 5.00 |
4.94 |
107.29 |
2.953 |
4.25 |
76.00 |
8.5 |
7.5 |
+3.25 to +4.00 |
| 6.00 |
5.92 |
89.53 |
3.561 |
6.25 |
76.00 |
6.5 |
7.5 |
+4.25 to +5.00 |
| 7.00 |
6.98 |
75.93 |
4.235 |
6.25 |
76.00 |
8.0 |
7.5 |
+5.25 to +6.00 |
TrilogyTM Material Specific Processing Tips The following should be used as a guideline as different equipment may require slightly different setting and times. These suggestions reflect a compilation from the following types of generators, Coburn 113, Coburn 1008, Gerber-Coburn SG8 and Optronics generators.
Minimum Thickness
TrilogyTM lenses can be processed to a minimum thickness of 1.0mm and are compliant with the FDA dress eyewear impact requirements.
Impact Resistance
TrilogyTM lenses have been formulated to meet or exceed applicable impact resistance requirements when laboratory finished as set forth in FDR CFR 801.410, ANSI Z80.1 and ANSI Z87.1. Any modification of Trilogy lenses other than normal surfacing or edging may adversely affect impact performance characteristics. Additional coating of Trilogy lenses may adversely affect the impact
resistance performance. “Impact Resistance” lenses are neither shatter proof nor unbreakable.
Surface Layout
Optical center should be placed at the geometric center of the lens.
Blocking - Alloy
Use large 50 mm blocks to provide adequate lens support during the generating process. Maintain alloy temperature of 120o – 122oF. Allow lenses to cool for at least 30 minutes prior to generating.
Blocking - One Step (wax)
Follow manufacturers recommendations. Cool blocked lenses from 12 to 18 minutes.
Generating
Reduce stock removal to approximately 1 to 2 millimeter per sweep, with a final of .5mm.
Fining
Using two-step, each fine should be from 1.5 minutes to 2 minutes each. Recommended pads are 280 grit for first fine, followed by a 1000 grit for the second fine.
Polishing
Use equivalent polishing times and conditions for Polycarbonate, 5 to 7 minutes depending on pressures and polish being used.
Cleaning and Tinting
- The use of a mild soap and warm water is best recommended to clean the back uncoated side of the lens prior to tinting.
- Use warm water to rinse lens after tinting.
De-blocking and Cleaning
Step-OneTM
- Use the Step-One de-blocking station to remove the Freebond block.
- Use the Lens Washing Station to remove the remaining Freebond from the lens surface.
Alloy Type
- A knock-off technique is recommended.
- Peel off the tape and wash the lens in warm water with a mild liquid detergent. Rinse with fresh running warm water.
Edging
TrilogyTM works well with most dry or wet edgers.
Drilling
Ensure that drill bits used are extremely sharp and drill at slower speed as for polycarbonate.
Tinting Tips
- TrilogyTM blocks 100% of UVA and UVB so no additional UV treatment is needed
- TrilogyTM tints faster than uncoated CR39, so tinting times can be reduced.
- Tinting should be applied before backside coating is applied.
Fining and Polishing
| First Fine- |
Pad: |
280 grit Black (Poly type – 7 leaf) |
| Pressure: |
16-18psi |
| Time: |
1 minute 30 seconds to 2 minutes |
| Coolant: |
60F or less |
| |
| Second Fine- |
Pad: |
1000 grit Brown (Poly type – 7 leaf) |
| Pressure: |
16-18psi |
| Time: |
1 minute 30 seconds to 2 minutes |
| Coolant: |
60F or less |
| |
| Polish - |
Pad: |
Velveteen 3” Heavy Polish Pad |
| Pressure: |
16-18psi |
| Time: |
5 to 7 minutes approximately |
| Polish: |
Standard CR39 Polish |
Recommended Base Curve Selection Chart
click for larger image
|
|
For generations, people have trusted the Kodak
name for quality, reliability, and innovation.
Click to learn more. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
