Method for deciding a bevel curve, method for determining a locus of a bevel, method for processing a lens and apparatus for processing a lens

A method for determining a locus of a bevel in an EX lens comprising the steps of:

• calculating a value of a bevel curve based on a value of the curve of a concave face of the EX lens;
• determining a location of a first reference position on a peripheral edge of the EX lens in a first portion having a minimum thickness at a lower side in a vertical direction of the EX lens, wherein the position of the first reference position is determined based on a thickness of the first portion of the EX lens having the minimum thickness;
• determining a location of a second reference position on a peripheral edge in a second portion of the EX lens having a maximum thickness at an upper side in a vertical direction of the EX lens, wherein determination of the second reference position is based on a ratio of the thickness of the second portion having the maximum thickness to the thickness of the first portion having the minimum thickness;
• calculating an angle of inclination relative to the direction of an initial reference axis of the EX lens, wherein the angle of inclination calculation is based on data describing a shape of the EX lens to be obtained by processing;
• and,
• determining the locus of the bevel based on the value of the bevel curve, the first reference position and the second reference position.

A method for determining a locus of a bevel in an EX lens comprising the steps of:

• calculating a value of a bevel curve based on a value of the curve of a concave face of the EX lens;
• determining an orientation of an initial reference axis of the bevel curve to be in the same direction as a direction of the curvature of the concave face of the EX lens;
• determining a location of a first reference position of the bevel on a peripheral edge of the EX lens in a first portion having a minimum thickness at a lower side in a vertical direction of the EX lens, wherein the position of the first reference position is based on a thickness of the first portion of the EX lens having the minimum thickness;
• calculating a correction value for the initial reference axis of the bevel curve, wherein the correction value calculation is based on a ratio of a thickness of a second portion of the EX lens having a maximum thickness at an upper side in a vertical direction of the EX lens to a thickness of the first portion of the EX lens having the minimum thickness;
• calculating an angle of inclination of a reference axis of the bevel curve from a direction of the initial reference axis of the bevel curve, wherein the angle of inclination calculation is based on the correction value for the initial reference axis of the bevel curve and data describing a shape of the EX lens to be obtained by processing;
• and,
• determining the locus of the bevel based on the value of the bevel curve, the first reference position of the bevel and the angle of inclination of the reference axis.

A method for determining a locus of a bevel in a high power minus lens comprising the steps of

• calculating a value of a bevel curve based on a value of the curve of a convex face of the high power minus lens;
• determining a location of a first reference position, which is decided to be on a peripheral edge of the high power minus lens in a first portion having a minimum thickness of the high power minus lens, wherein this first portion having the minimum thickness is on a side of the lens that is closest to a wearer's nose, wherein the location of the first reference position is based on a thickness of this first portion having the minimum thickness;
• calculating a location of a second reference position on a peripheral edge of the high power minus lens in a second portion having a maximum thickness of the high power minus lens, wherein this second portion having the maximum thickness is on the side of the lens that is closest to a wearer's nose, wherein the calculation of the second reference position is based on a ratio of a thickness of the second portion having a maximum thickness to the thickness of the first portion having a minimum thickness;
• calculating an angle of inclination relative to the direction of an initial reference axis of the high power minus lens, wherein the angle of inclination calculation is based on data describing a shape of the high power minus lens to be obtained by processing;
• and,
• determining the locus of the bevel based on the value of the bevel curve, the first reference position and the second reference position.

A method for determining a locus of a bevel in a high power minus lens comprising the steps of:

• calculating a value of a bevel curve based on a value of the curve of a convex face of the high power minus lens;
• determining an orientation of an initial reference axis of a bevel curve to be in the same direction as a direction of the curvature of the convex face of the high power minus lens;
• determining a location of a first reference position of the bevel on a peripheral edge of the high power minus lens in a first portion having a minimum thickness of the high power minus lens, wherein the first portion having the minimum thickness is on a side of the lens that is closest to a wearer's nose, wherein the location of the first reference position is based on a thickness of the first portion having the minimum thickness;
• calculating a correction value for the initial reference axis of the bevel curve, wherein the correction value calculation is based on a ratio of a thickness of a second portion having a maximum thickness of the high power minus lens to the thickness of the first portion having the minimum thickness, wherein the second portion having the maximum thickness is on the side of the lens that is closest to a wearer's nose;
• calculating an angle of inclination of a reference axis of the bevel curve from a direction of the initial reference axis of the bevel curve, wherein the angle of inclination calculation is based on the correction value for the initial reference axis of the bevel curve and data describing a shape of the high power minus lens to be obtained by processing;
• and,
• determining the locus of the bevel based on the value of the bevel curve, the reference position of the bevel and the angle of inclination of the reference axis.

A method for determining a locus of a bevel in a lenticular lens comprising the steps of:

• calculating a value of a bevel curve based on a value of the curve of a concave face of the lenticular lens;
• determining a location of a reference position of the bevel on a peripheral edge of the lenticular lens in a first portion having a minimum thickness, wherein this first portion having the minimum thickness is on a side of the lens that is closest to a wearer's nose, wherein the location of the reference position is based on a thickness of the first portion having the minimum thickness;
• calculating a correction value of a curve based on a ratio of the thickness of the first portion having the minimum thickness to the thickness of a second portion having a maximum thickness of the lenticular lens in a vertical direction;
• and,
• determining the locus of the bevel, having a value of a corrected curve, by adding the correction value of a curve to the value of the bevel curve that passes through the reference position of the bevel.

A method for determining a locus of a bevel in a high power plus lens comprising the steps of:

• calculating a value of a bevel curve based on a value of the curve of a concave face of the high power plus lens;
• determining a location of a reference position of the bevel on a peripheral edge of the high power plus lens in a first portion having a minimum thickness of the high power plus lens, wherein the location of the reference position is based on a thickness of the first portion having the minimum thickness;
• calculating a correction value of a curve based on a ratio of the value of a first curve of the concave face of the high power plus lens to a value of a second curve of a convex face of the high power plus lens, or based on the value of the first curve of a convex face of the high power plus lens;
• and,
• determining the locus of the bevel, which has a value of a corrected curve, by adding the correction value of a curve to the value of the bevel curve that passes through the reference position of the bevel.

An apparatus for processing a lens comprising:

• a means for determining a value of a bevel curve based on a value of a curve of a concave face of an EX lens;
• a means for determining a first reference position on a peripheral edge in a portion having a minimum thickness at a lower side in a vertical direction of the EX lens based on a thickness of the portion having a minimum thickness;
• a means for determining a second reference position on a peripheral edge in a portion having a maximum thickness at an upper side in a vertical direction of the EX lens based on a ratio of a thickness of the portion having a maximum thickness to the thickness of the portion having a minimum thickness and data of a shape of the EX lens to be obtained by the processing;
• a means for determining the locus of the bevel based on the value of the bevel curve, the first reference position and the second reference position;
• and
• a means for forming the bevel along the locus of the bevel determined by the means for determining the locus of the bevel.

An apparatus for processing a lens comprising:

• a means for determining a value of a bevel curve based on a value of a curve of a concave face of an EX lens;
• a means for determining an initial reference axis of the bevel curve in a same direction as a direction of a curvature of the concave face of the EX lens;
• a means for determining a reference position of the bevel on a peripheral edge in a portion having a minimum thickness at a lower side in a vertical direction of the EX lens based on a thickness of the portion having a minimum thickness;
• a means for calculating a value of correction for an initial reference axis of the bevel curve based on a ratio of a thickness of a portion having a maximum thickness at an upper side in a vertical direction of the EX lens to a thickness of the portion having a minimum thickness;
• a means for calculating an angle of inclination of an axis from a direction of the initial reference axis of the bevel curve based on the value of correction for the initial reference axis of the bevel curve and data of a shape of the EX lens to be obtained by the processing;
• a means for determining a locus of the bevel based on the value of the bevel curve, the reference position of the bevel and the angle of inclination of the axis;
• and
• a means for forming the bevel along the locus of the bevel determined by the means for determining the locus of the bevel.

An apparatus for processing a lens comprising:

• a means for determining a value of a bevel curve based on a value of a curve of a convex face of a high power minus lens;
• a means for determining a first reference position on a peripheral edge in a portion having a minimum thickness of the high power minus lens at a side of a nose of a person wearing the high power minus lens based on a thickness of the portion having a minimum thickness;
• a means for determining a second reference position on a peripheral edge in a portion having a maximum thickness of the high power minus lens at a side of an ear of a person wearing the high power minus lens based on a ratio of a thickness of the portion having a maximum thickness to the thickness of the portion having a minimum thickness and data of a shape of the high power minus lens to be obtained by the processing;
• a means for determining the locus of the bevel based on the value of the bevel curve, the first reference position and the second reference position;
• and
• a means for forming the bevel along the locus of the bevel determined by the means for determining the locus of the bevel.

An apparatus for processing a lens comprising:

• a means for determining a value of a bevel curve based on a value of a curve of a convex face of a high power minus lens;
• a means for determining an initial reference axis of the bevel curve in a same direction as a direction of a curvature of the convex face of the high power minus lens;
• a means for determining a reference position of the bevel on a peripheral edge in a portion having a minimum thickness of the high power minus lens at a side of a nose of a person wearing the high power minus lens based on a thickness of the portion having a minimum thickness;
• a means for calculating a value of correction for an initial reference axis of the bevel curve based on a ratio of a thickness of a portion having a maximum thickness of the high power minus lens at a side of an ear of a person wearing the high power minus lens and a thickness of the portion having a minimum thickness;
• a means for calculating an angle of inclination of an axis of a reference axis of the bevel curve from a direction of the initial reference axis of the bevel curve based on the value of correction for the initial reference axis of the bevel curve and data of a shape of the high power minus lens to be obtained by the processing;
• a means for determining the locus of a bevel based on the value of the bevel curve, the reference position of the bevel and the angle of inclination of the axis;
• and
• a means for forming the bevel along the locus of the bevel determined by the means for determining the locus of the bevel.

An apparatus for processing a lens which comprises:

• a means for determining a value of a bevel curve based on a value of a curve of a concave face of a lenticular lens;
• a means for determining a reference position of the bevel on a peripheral edge in a portion having a minimum thickness at a side of a nose or a ear of a person wearing the lenticular lens based on a thickness of the portion having a minimum thickness;
• a means for determining a correction for a value of a curve based on a ratio of the thickness of the portion having a minimum thickness of the lenticular lens at a side of a nose or an ear to a thickness of a portion having a maximum thickness of the lenticular lens in a vertical direction;
• a means for determining the locus of the bevel having a value of a curve obtained by adding the correction for a value of a curve to the value of the bevel curve and passes through the reference position of the bevel;
• and
• a means for forming the bevel along the locus of the bevel determined by the means for determining the locus of the bevel.

An apparatus for processing a lens comprising:

• a means for determining a value of a bevel curve based on a value of a curve of a concave face of a high power plus lens;
• a means for determining a reference position of the bevel on a peripheral edge in a portion having a minimum thickness of the high power plus lens based on a thickness of the portion having a minimum thickness;
• a means for determining a correction for a value of a curve based on a ratio of the value of a curve of the concave face to a value of a curve of a convex face of the high power plus lens or based on the value of a curve of a convex face alone of the high power plus lens;
• a means for determining the locus of the bevel having a value of a curve obtained by adding the correction for a value of a curve to the value of the bevel curve and passes through the reference position of the bevel;
• and
• a means for forming the bevel along the locus of the bevel determined by the means for determining the locus of the bevel.