Soft optical element for use in eye-protecting devices
An optical element is disclosed comprising at least one transparent eye-protecting portion comprising a plastic material, preferably having a hardness within a range of about 40 Shore A to about 77 Shore D, as measured according to ASTM Standard D2240, and an elongation at break within a range of about 200% to about 700%, as measured according to ASTM Standard D638.
1. An optical element comprising at least one transparent eye-protecting portion comprising a plastic material, said eye-protecting portion comprising:
i) a hardness in a range between about 40 Shore A and about 77 Shore D, as measured according to ASTM Standard D2240; and
ii) an elongation at break in a range between about 200% and about 700%, as measured according to ASTM Standard D638.
2. The optical element according to claim 1 , wherein the hardness is in a range between about 55 Shore A and 65 Shore D, as measured according to ASTM Standard D2240.
3. The optical element according to claim 1 , wherein the elongation at break is in a range between about 300% and about 600%, as measured according to ASTM Standard D638.
4. The optical element according to claim 1 , wherein the eye-protecting portion comprises an elongation at yield that is higher than about 15%, as measured according to ASTM Standard D638.
5. The optical element according to claim 1 , wherein the eye-protecting portion comprises a light transmission not lower than about 85%, as measured according to ASTM Standard D1003.
6. The optical element according to claim 1 , wherein the eye-protecting portion comprises a haze not higher than 1.5%, as measured according to ASTM Standard D1003.
7. The optical element according to claim 1 , wherein the eye-protecting portion comprises a refractive index lower than about 1.59, as measured according to ASTM Standard D542.
8. The optical element according to claim 1 , wherein the eye-protecting portion comprises a polyurethane material.
9. The optical element according to claim 8 , wherein said polyurethane material is selected from a group comprising polyurea-urethanes, thermoplastic poliurethanes and thermoplastic urea-urethanes.
10. The optical element according to claim 8 , wherein said polyurethane material is substantially elastomeric.
11. The optical element according to claim 9 , wherein said polyurethane material is substantially elastomeric.
12. The optical element according to claim 1 , wherein the optical element is a semi-finished product suitable for use in the manufacture of oculars for eyeglasses.
13. The optical element according to claim 1 , wherein the optical element is an ocular.
14. The optical element according to claim 13 , wherein said ocular is a lens for eyeglasses.
15. The optical element according to claim 13 , wherein said ocular is a visor.
16. The optical element according to claim 13 , wherein said ocular is a protection mask.
17. The optical element according to claim 13 , wherein said ocular is a an add-on lens for eyeglasses.
18. An eye-protecting device comprising an optical element according to claim 1 .
19. An eye-protecting device according to claim 18 , wherein said device is a rimless eyewear.