Vision shift amount measuring method and vision shift amount measuring jig
A vision shift amount measuring method includes: forming a reference mark indicating a distance eye point on a surface of a spectacle lens attached to a spectacle frame practically worn by a wearer, and forming a plurality of opaque lines in an area expected to contain a shifted vision on the surface of the spectacle lens with a predetermined space between the adjoining lines; and allowing the wearer wearing the spectacle frame to select the line closest to a position through which the vision passes from the plural formed lines.
1. A vision shift amount measuring method comprising:
forming a reference mark indicating a distance eye point on a surface of a spectacle lens attached to a spectacle frame practically worn by a wearer, and forming a plurality of opaque lines in an area expected to contain a shifted vision on the surface of the spectacle lens with a predetermined space between the adjoining lines; and
allowing the wearer wearing the spectacle frame to select the line closest to a position through which the vision passes from the plural formed lines.
wherein a vision shift amount comprises an eyeball outward movement produced when an outside of the spectacle lens is viewed by the wearer and an eyeball inward movement produced when an inside of the spectacle lens is viewed by the wearer.
2. The vision shift amount measuring method according to claim 1 , wherein the plural lines are disposed such that the distance between the centers of the adjoining lines lies in the range from 1.5mm to 2.5mm.
3. The vision shift amount measuring method according to claim 1 , wherein each width of the lines lies in the range from 0.1mm to 1.5mm.
4. The vision shift amount measuring method according to claim 1 , wherein at least the adjoining lines of the plural lines have colors different from each other.
5. The vision shift amount measuring method according to claim 1 , wherein the plural lines are formed in an area expected to contain a near eye point on the surface of the spectacle lens and disposed in parallel with a horizontal visible field which passes through the distance eye point and extends in the horizontal direction.
6. The vision shift amount measuring method according to claim 1 , wherein the plural lines are formed in an area expected to contain one end of a horizontal visible field which passes through the distance eye point and extends in the horizontal direction, and are disposed in the direction crossing the horizontal visible field at right angles.
7. The vision shift amount measuring method according to claim 1 , wherein the reference mark and the plural lines are formed by directly applying ink to the spectacle lens using a stamp.
8. The vision shift amount measuring method according to claim 1 , wherein the reference mark and the plural lines are formed by directly applying ink to the spectacle lens using an ink jet.
9. The vision shift amount measuring method according to claim 1 , wherein the reference mark and the plural lines are formed by producing the reference mark and the plural lines on a surface of a tape capable of adhering to the surface of the spectacle lens, and affixing the tape to the surface of the spectacle lens attached to the spectacle frame practically worn by the wearer with alignment between the distance eye point of the spectacle lens and the reference mark formed on the tape.
10. A vision shift amount measuring jig, comprising:
a spectacle holding stand that holds a spectacle having a spectacle frame to which a spectacle lens is attached, wherein
a lens carrying unit which contains low-repulsive material provided at a position corresponding to the spectacle lens, and a stamp forming unit which contains convex projections disposed at positions corresponding to a reference mark indicating a distance eye point and a plurality of opaque lines provided in an area expected to contain a shifted vision on the surface of the spectacle lens with a predetermined space between the adjoining lines are provided on the upper surface of the spectacle holding stand, and
a vision shift amount comprises an eyeball outward movement produced when an outside of the spectacle lens is viewed by a wearer and an eyeball inward movement produced when an inside of the spectacle lens is viewed by the wearer.
11. The vision shift amount measuring jig according to claim 10 , wherein the projection corresponding to the reference mark is provided in such a manner as to freely move in the horizontal direction of the spectacle lens.
12. The vision shift amount measuring jig according to claim 10 , further comprising a frame supporting member attached in such a manner as to freely move in the direction crossing the horizontal direction of the spectacle lens at right angles to support the spectacle frame.