1. A container comprising:
a base having portions defining an interior and having an upper wall;
a lid having an upper wall, the lid being releasably engageable with the base so the lid upper wall overlies the base upper wall;
portions of the lid upper wall which define a lid projection, wherein a region of weakened material extends around the lid projection;
a signal tab connected by a first hinge to the base; and
a projection extending from the signal tab, wherein the signal tab is pivotable about the hinge to engage and connect the signal tab projection with the lid projection, such that when, after said engagement, the signal tab is pivoted away from the container lid, the lid projection which is connected to the signal tab projection is caused to be severed from the lid upper wall at the region of weakened material, thereafter preventing the lid projection from being secured to the lid upper wall and providing an indication of the prior manipulation of the signal tab.
2. The container of claim 1 further comprising portions of the base upper wall which define a relief below the base upper wall, and wherein the lid projection extends into the relief when the lid is closed on the base.
3. The container of claim 2 wherein the relief comprises a closed cavity which extends beneath the base upper wall.
4. The container of claim 1 wherein the lid has a top wall with a downwardly extending peripheral skirt spaced from a downwardly extending interior skirt, and where the base has a downwardly extending peripheral skirt spaced outwardly from a base side wall, and wherein the lid peripheral skirt and interior skirt engage the base peripheral skirt and side wall to retain the lid on the base when it is closed thereon.
5. The container of claim 1 wherein the signal tab comprises:
a first element which extends outwardly from the first hinge to a second hinge; and
a second element which extends outwardly from the second hinge, the hinge tab projection extending from the second element.
6. The container of claim 1 wherein the base upper wall extends to underlie the region of weakened material, such that downward force on the lid projection is resisted by the base upper wall and severing of the region of weakened material is resisted.
7. The container of claim 1 wherein the lid is connected to the base by a hinge, and is pivotable about the hinge from a position which reveals the container interior to a position which closes the container interior.
8. The container of claim 1 wherein the lid is separable from the base, and further comprising:
portions of the lid which define a second lid projection surrounded by a second region of weakened material, positioned opposite the lid projection;
a second signal tab connected by a second hinge to the base; and
a second projection extending from the second signal tab, wherein the second signal tab is pivotable about the second hinge to engage and connect the second signal tab projection with the second lid projection, such that when, after said engagement, the second signal tab is pivoted away from the container lid, the second lid projection which is connected to the second signal tab second projection is caused to be severed from the lid upper wall at the second region of weakened material, thereafter preventing the second lid projection from being secured to the lid and providing an indication of the prior manipulation of the second signal tab.
9. The container of claim 1 wherein the lid has a top wall which projects above the level of the lid upper wall, such that when the signal tab is engaged with the lid projection, the signal tab does not project substantially above the level of the lid top wall.
10. The container of claim 1 wherein the region of weakened material comprises a line of perforations which encircles the lid projection.
11. A container comprising:
a container first part having a first wall;
a container second part having portions defining a second wall, the second part being releasably engageable with the first part so the first wall and the second wall are substantially parallel and in close proximity, the engaged container first part and container second part defining a container interior;
portions of the first wall which define a first projection, wherein a region of weakened material extends around the first projection;
a signal tab connected by a hinge to the container second part; and
a second projection extending from the signal tab, wherein the signal tab is pivotable about the hinge and the second projection is configured to cooperate with the first projection to secure the signal tab second projection to the container first part first projection, such that after said engagement, pivoting of the signal tab away from the container first part causes the first projection to be severed from the first part first wall at the region of weakened material thereafter preventing the signal tab second projection from being secured to the container first part first wall and providing an indication of the prior manipulation of the signal tab.
12. The container of claim 11 further comprising portions of the first container part which engage with portions of the second container part to engage them together and retain the container in a closed configuration.
13. The container of claim 11 wherein the signal tab comprises:
a first element which extends outwardly from the hinge to a second hinge; and
a second element which extends outwardly from the second hinge, the hinge tab second projection extending from the second element.
14. The container of claim 11 wherein the container first part is entirely separable from the container second part, and wherein portions of the container first part and container second part define a second tamper evident mechanism positioned opposite the signal tab.
15. The container of claim 11 wherein the signal tab second projection and the container first part first projection are configured to engage with each other in a friction fit.
16. A container comprising:
a base having an upper wall, and a side wall which extends downwardly from the upper wall to a bottom wall, the base defining a container interior;
a lid having an upper wall, the lid being releasably engageable with the base so the lid upper wall overlies the base upper wall, and so the lid closes the container interior;
portions of the base which define a relief below the base upper wall;
portions of the lid upper wall which define a downwardly extending lid projection, the lid projection extending into the base relief when the lid is closed on and engaged with the base, wherein a region of weakened material extends around the lid projection;
a signal tab hingedly connected to the base; and
a projection extending from the signal tab to be received within the lid projection and engaged thereto, such that when the signal tab is pivoted away from the container lid, the lid projection is severed from the lid upper wall at the region of weakened material thereafter preventing the lid projection from being secured to the lid upper wall and providing an indication of the prior manipulation of the signal tab.
17. The container of claim 16 wherein the relief comprises portions of the base which define a downwardly extending closed projection.
18. The container of claim 16 wherein the signal tab is connected to the base by a first hinge, and further comprises:
a first element which extends outwardly from the first hinge to a second hinge; and
a second element which extends outwardly from the second hinge, the hinge tab projection extending from the second element.
19. The container of claim 16 further comprising portions of the lid which engage the base to retain the container in a closed configuration.
20. The container of claim 17 wherein the lid is entirely separable from the base, and wherein portions of the lid and base define a second tamper evident mechanism positioned opposite the signal tab.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A progressive spectacle lens having two aspherical, progressive surfaces which contribute to a rise in the effect (addition Add.) from a distance view portion to a near view portion, wherein the sagittal heights
zi=zi(x,y)
of at least one (i) progressive surface (i=1,2) are chosen such that the sagittal height z of this respective surface at the edge of the spectacle lens given by
yi=fi1(x) for y\u22670 and
yi=fi2(x) for y<0
assume predefined values without this surface (i) or the other surface (j) having a reversal of curvature serving to form a supporting edge.
2. A spectacle lens according to claim 1, wherein the peripheral region of at least one of said surfaces is configured in a largely free manner.
3. A spectacle lens according to claim 1, wherein the predefined values of the sagittal heights z of the respective surfaces at the edge of the lens are substantially determined by geometric predefinitions, and wherein, in spite of the compliance with these predefinitions, the optical properties of the spectacle lens are not noticeably degraded either in the central region or in the edge region relative to an equivalent spectacle lens having one progressive surface in which the course of the edge is not predefined.
4. A spectacle lens according to claim 3, wherein the total astigmatism at any point on the spectacle lens does not exceed a value of 1.5*Add.
5. A spectacle lens according to claim 4, wherein the total astigmatism at any point on the spectacle lens does not exceed a value of 1.1*Add.
6. A spectacle lens according to claim 3, wherein no point on the spectacle lens has a refraction error exceeding a value of 1*Add.
7. A spectacle lens according to claim 6, wherein no point of the spectacle lens has a refraction error exceeding a value of 0.7*Add.
8. A spectacle lens according to claim 3, wherein the edge is the edge of the bordered spectacle lens predefined by an individually selected spectacle frame.
9. A spectacle lens according to claim 3, wherein the edge is the edge of a raw round spectacle lens.
10. A spectacle lens according to claim 1, wherein the rise in the effect Add. from the distance portion to the near portion predefined by the prescription of the lens is divided between the front surface (i=1) and the eye-side surface (i=2) such that the sagittal heights zi of the at least one surface (i) have the predefined values.
11. A spectacle lens according to claim 10, wherein the sagittal height zj\u2260i of the other surface (j) at the edge is selected in such a way that the variation in the edge thickness along the periphery of the spectacle lens is lower than that of an equivalent progressive spectacle lens having only one aspheric-progressive surface.
12. A spectacle lens according to claim 11, wherein the peripheral edge of the lens has a variation in edge thickness at least 30% less than a progressive spectacle lens having the same distance portion effect and addition and having only one progressive surface.
13. A spectacle lens according to claim 12, wherein the peripheral edge of the lens has a variation in edge thickness at least 50% less than a progressive spectical lens having the same distance portion effect and addition and having only one progressive surface.
14. A spectacle lens according to claim 11, wherein the lens in a raw round state has a peripheral edge thickness which varies by less than 40%.
15. A spectacle lens according to claim 14, wherein the lens in a raw round state has a peripheral edge thickness w which varies by less than 25%.
16. A spectacle lens according to claim 1, wherein the lens has an astigmatic prescription and at least one of the two surfaces has a surface astigmatism with a magnitude and axial position which at least substantially correct the astigmatism of the eye.
17. A spectacle lens according to claim 16, wherein the surface astigmatism is selected such that the surface astigmatism at least substantially corrects the astigmatism of the eye while taking account of the astigmatism of oblique beams.
18. A spectacle lens according to claim 16, wherein one surface (i) at least substantially incorporates the astigmatic prescription in the distance portion and the other surface (j) at least substantially incorporates the astigmatic prescription in the near portion.
19. A spectacle lens according to claim 18, wherein the distance portion and the near portion of the lens exhibit different amounts of astigmatism or different axial positions.
20. A spectacle lens according to claim 1, wherein the distance portion and the near portion have limits given by an ISO surface astigmatism line with a specific absolute value, and said limits have a different course on the front surface (i=1) and on the eye-side surface (i=2).
21. A spectacle lens according to claim 20, wherein the lens has an astigmatism-free prescription, and the distance portion and the near vision portion are delimited by an ISO astigmatism line which is a 0.5 diopter line of the surface astigmatism.
22. A spectacle lens according to claim 1, wherein the effect rises from the distance portion to the near portion along a main line curve which curves toward the side of a wearer’s nose.
23. A spectacle lens according to claim 22, wherein the main line curve between the distance portion and the near portion is offset differently on the front surface than on the eye-side surface of the lens.
24. A spectacle lens according to claim 22, wherein the lens is for an astigmatism-free prescription, and the surface astigmatism on the main lines has a minimum.
25. A spectacle lens according to claim 22, wherein the lens has an astigmatic prescription, and the surface astigmatism most closely approaches the value of the astigmatic prescription in the central region of the spectacle lens.
26. A spectacle lens according to claim 22, wherein the lens has an astigmatic prescription, and the surface astigmatism changes at least approximately linearly perpendicular to the main line in a strip on both sides of the main line.
27. A spectacle lens according to claim 1, wherein the length of the progression zone or the course of the progression rise along the main line is different on the front surface than on the eye-side surface of the lens.
28. A method of calculating a progressive spectacle lens according to claim 1, said method comprising selecting initial conditions for a double strip on both sides of the main lines of the front surface and the eye-side surface such that when the lens has a surface configuration which satisfies a predefined target function, the predefined courses of the sagittal heights z of the edges of the surfaces are obtained.
29. A method according to claim 28, wherein when the lens has a surface configuration which satisfies the predefined target function, the lens has an edge thickness variation which is lower than the edge thickness variation of an equivalent progressive spectacle lens having only one progressive surface.
30. A method according to claim 28, wherein the predefined target function corresponds to that of a progressive spectacle lens having only one progressive surface which is optimized without taking into account the course of the edge.
31. A method according to claim 28, wherein the surface configuration of the lens is optimized such that the lens has a critical thickness which is minimized.
32. A progressive spectacle lens having two progressive surfaces contributing to a rise in effect Add. from a distance portion to a near portion, wherein the effect rises along a main line from the distance portion to the near portion, and the main line is formed as a curve which curves toward a side of a wearer’s nose, and wherein the main line curve between the distance portion and the near portion is offset differently on the front surface than on the eye-side surface of the lens.
33. A progressive spectacle lens according to claim 32, wherein the sagittal heights
zi=zi(x,y)
of at least one (i) of the progressive surfaces (i=1,2) are chosen such that the sagittal height z of this respective surface at the edge of the spectacle lens given by
yi=fi1(x) for y\u22670 and
yi=fi2(x) for y<0
assume predefined values without this surface (i) or the other surface (j) having a reversal of curvature which forms a supporting edge.
34. A spectacle lens according to claim 33, wherein at least one surface of the lens has a peripheral region which is configured in a substantially free manner.
35. A spectacle lens according to claim 33, wherein the lens front and eye-side surfaces at the edge of the lens have sagittal heights z with predefined values substantially determined by geometric predefinitions, and wherein, despite compliance with these predefinitions, the spectacle lens has optical properties which are not noticeably degraded either in the central region or in the edge region relative to an equivalent spectacle lens having one progressive surface in which the course of the edge is not predefined.
36. A spectacle lens according to claim 35, wherein the total astigmatism at any point on the spectacle lens does not exceed a value of 1.5*Add.
37. A spectacle lens according to claim 36, wherein the total astigmatism at any point on the spectacle lens does not exceed a value of 1.1*Add.
38. A spectacle lens according to claim 35, wherein no point on the spectacle lens has a refraction error exceeding a value of 1*Add.
39. A spectacle lens according to claim 38, wherein no point on the spectacle lens has a refraction error exceeding a value of 0.7*Add.
40. A spectacle lens according to claim 33, wherein the edge is the edge of the bordered spectacle lens predefined by an individually selected spectacle frame.
41. A spectacle lens according to claim 33, wherein the edge is the edge of a raw round spectacle lens.
42. A spectacle lens according to claim 32, wherein the rise in the effect Add. from the distance portion to the near portion predefined by the prescription of the lens is divided between the front surface (i=1) and the eye-side surface (i=2) such that the sagittal heights zi of the at least one surface (i) have predefined values.
43. A spectacle lens according to claim 32, wherein the sagittal height zj\u2260i of the other surface (j) at the edge is selected in such a way that the variation in the edge thickness along the periphery of the spectacle lens is lower than that of an equivalent progressive spectacle lens having only one aspheric-progressive surface.
44. The spectacle lens according to claim 43, wherein the peripheral edge of the lens has a variation in edge thickness at least 30% less than an equivalent progressive spectacle lens having the same distance portion effect and the same rise in the effect Add., and having only one progressive surface.
45. The spectacle lens according to claim 44, wherein the peripheral edge of the lens has a variation in edge thickness at least 50% less than an equivalent progressive spectacle lens having the same distance portion effect and the same rise in the effect Add., and having only one progressive surface.
46. A spectacle lens according to claim 43, wherein the lens in a raw round state has a peripheral edge thickness which varies by less than 40%.
47. A spectacle lens according to claim 46, wherein the lens in a raw round state has a peripheral edge thickness which varies by less than 25%.
48. A spectacle lens according to claim 32, wherein the lens has an astigmatic prescription, and at least one of the two surfaces has a surface astigmatism with a magnitude and axial position which at least substantially correct the astigmatism of the eye of a wearer.
49. A spectacle lens according to claim 48, wherein the surface astigmatism is selected such that the surface astigmatism at least substantially corrects the astigmatism of the eye while taking account of the astigmatism of oblique beams.
50. A spectacle lens according to claim 48, wherein one surface (i) at least substantially incorporates the astigmatic prescription in the distance portion, and the other surface (j) at least substantially incorporates the astigmatic prescription in the near portion.
51. A spectacle lens according to claim 50, wherein the distance portion and the near portion of the lens exhibit different amounts of astigmatism or different axial positions.
52. A spectacle lens according to claim 32, wherein the distance portion and the near portion have limits given by an ISO surface astigmatism line with a specific absolute value, and said limits have a different course on the front surface (i=1) and on the eye-side surface (i=2) of the lens.
53. A spectacle lens according to claim 52, wherein the lens has an astigmatism-free prescription, and the distance portion and the near vision portion are delimited by an ISO astigmatism line which is a 0.5 diopter line of the surface astigmatism.
54. A spectacle lens according to claim 32, wherein the lens is for an astigmatism-free prescription, and the surface astigmatism on the main lines has a minimum.
55. A spectacle lens according to claim 32, wherein the lens has an astigmatic prescription, and the surface astigmatism most closely approaches the value of the astigmatic prescription in the central region of the spectacle lens.
56. A spectacle lens according to claim 32, wherein the lens has an astigmatic prescription, and the surface astigmatism changes at least approximately linearly perpendicular to the main line in a strip on both sides of the main line.
57. A spectacle lens according to claim 32, wherein the length of the progression zone or the course of the progression rise along the main line is different on the front surface than on the eye-side surface of the lens.
58. A method of calculating a progressive spectacle lens according to claim 32, said method comprising defining a target function, and selecting initial conditions for a double strip on both sides of the main lines of the front surface and the eye-side surface such that when the lens has a surface configuration which satisfies the target function, the predefined courses of the sagittal heights z of the edges of the surfaces are obtained.
59. A method according to claim 21, wherein the lens has a surface configuration which satisfies the target function, and the lens has an edge thickness variation which is lower than the edge thickness variation of an equivalent progressive spectacle lens having only one progressive surface.
60. A method according to claim 58, wherein the target function corresponds to that of a progressive spectacle lens having only one progressive surface which is optimized without taking into account the course of the edge.
61. A method according to claim 58, wherein the surface configuration of the lens is optimized such that the lens has a critical thickness which is minimized.