Progressive addition power lens
A progressive addition power lens with a length of the intermediate corridor in the range of 22 to 28 mm, and a clear visual region, which is defined as a region where astigmatism is 0.5 diopters or less, has a horizontally maximum width thereof in the distant dioptric power region, which is twice as thick as or less than a horizontally minimum width in the intermediate corridor. Furthermore, the clear visual region defined as a region where astigmatism is 0.5 diopters or less has a width of 30 mm or more horizontally in the near dioptric power region. In addition, a position, where astigmatism distributed at the sides of the lens has the maximum value, is located in an almost horizontal direction with a far point positioned above the intermediate corridor or is located above the far point.
1. A progressive addition power lens comprising:
a near dioptric power region, an intermediate corridor, and a far dioptric power region, each with a respective clear visual region having astigmatism of 0.5 diopters or less;
wherein:
the intermediate corridor extends vertically from the near dioptric power region to the far dioptric power region, with a gradually decreasing refractive power;
a maximum horizontal width of the clear visual region in the far dioptric power region is no more than twice a minimum horizontal width of the clear visual region in the intermediate corridor;
a vertical length of the intermediate corridor is in a range of 22 to 28 mm;
a far point at the bottom of the far dioptric power region; and
astigmatism peaks positioned only at same height or vertically higher than the far point.
2. A progressive addition power lens comprising:
a near dioptric power region, an intermediate corridor, and a far dioptric power region, each with a respective clear visual region having astigmatism of 0.5 diopters or less; a near point at the top of the near dioptric power region; and
an eye point in the intermediate corridor, at a position 9 to 12 mm higher than the near point,
wherein:
the intermediate corridor extends vertically from the near dioptric power region to the far dioptric power region, with a gradually decreasing refractive power,
a maximum horizontal width of the clear visual region in the far dioptric power region is no more than twice a minimum horizontal width of the clear visual region in the intermediate corridor, and
a vertical length of the intermediate corridor is in a range of 22 to 28 mm.
3. The progressive addition power lens as set forth in claim 1 , wherein the clear visual region of the near dioptric power region has a horizontal width of 30 mm or more.
4. The progressive addition power lens as set forth in claim 3 , wherein the astigmatism peaks are located to the sides of the far point.
5. The progressive addition power lens as set forth in claim 3 , wherein the astigmatism peaks are located to the sides of the far point, with positions higher than the far point.
6. The progressive addition power lens as set forth in claim 1 , wherein the astigmatism peaks are located to the sides of the far point.
7. A progressive addition power lens comprising:
a near dioptric power region, an intermediate corridor, and a far dioptric power region, each with a respective clear visual region having astigmatism of 0.5 diopters or less;
a far point at the bottom of the far dioptric power region; and
astigmatism peaks located to the sides of the far point, positioned at substantially same height as the far point;
a near point at the top of the near dioptric power region; and
an eye point in the intermediate corridor, at a position 9 to 12 mm higher than the near point,
wherein:
the intermediate corridor extends vertically from the near dioptric power region to the far dioptric power region, with a gradually decreasing refractive power;
a maximum horizontal width of the clear visual region in the far dioptric power region is no more than twice a minimum horizontal width of the clear visual region in the intermediate corridor; and
a vertical length of the intermediate corridor is in a range of 22 to 28 mm.
8. The progressive addition power lens as set forth in claim 1 , wherein the astigmatism peaks are located to the sides of the far point, with positions higher than the far point.
9. A progressive addition power lens comprising:
a near dioptric power region, an intermediate corridor, and a far dioptric power region, each with a respective clear visual region having astigmatism of 0.5 diopters or less;
a far point at the bottom of the far dioptric power region;
astigmatism peaks located to the sides of the far point, with positions higher than the far point;
a near point at the top of the near dioptric power region; and
an eye point in the intermediate corridor, at a position 9 to 12 mm higher than the near point,
wherein:
the intermediate corridor extends vertically from the near dioptric power region to the far dioptric power region, with a gradually decreasing refractive power;
a maximum horizontal width of the clear visual region in the far dioptric power region is no more than twice a minimum horizontal width of the clear visual region in the intermediate corridor; and
a vertical length of the intermediate corridor is in a range of 22 to 28 mm.
10. The progressive addition power lens as set forth in claim 9 wherein the clear visual region of the near dioptric power region has a horizontal width of 30 mm or more.
11. The progressive addition power lens as set forth in claim 5 , further comprising:
a near point at the top of the near dioptric power region; and
an eye point in the intermediate corridor, at a position 9 to 12 mm higher than the near point.
12. A progressive power regions comprising;
a near dioptric power region, an intermediate corridor, and a far dioptric power region, each with a respective clear visual region having astigmatism of 0.5 diopters or less;
a far point at the bottom of the far dioptric power region; and
astigmatism peaks positioned at substantially same height or vertically higher than the far point;
wherein:
the intermediate corridor extends vertically from the near dioptric power region to the far dioptric power region, with at gradually decreasing refractive power;
a maximum horizontal width of the clear visual region in the far dioptric power region is no more than twice a minimum horizontal width of the clear visual region in the intermediate corridor;
a vertical length of the intermediate corridor is in a range of 22 to 28 mm, and the vertical length of the intermediate corridor is in a range of 24.5 to 25.5 mm.