DE2644450A1 - MULTIFOCAL LENS AND METHOD OF MANUFACTURING MULTIFOCAL LENS - Google Patents

Description

PATENT ADVOCATE DR. HERMANiN O. TH. DIEHL -Dl PLOMPHYS I KER D-8000 MÖNCHEN 19 - FLD GG EN STRAS S E 17 - T E LE FO N: 0 8 9/17 70 61

My file: A 11o7-D Munich, September 29, 1976

Dr. D / hot

American Optical Corporation Southbrldge, Massachusetts, USA

Multifocal lens and

Method of making a multifocal

Spectacle lenses

The invention relates to a multifocal spectacle lens whose a refractive surface through a meridional main curve running free of jumps into two corresponding lateral ones Halves is divided, in which the curvature of the meridional main curve varies so that at least one above the other first and second viewing zones with different, longitudinal of the main meridional plane with constant vertex refractive power, with the second viewing zone being constant Has vertex power, and the first viewing zone is subdivided in the transverse direction into at least three parts of finite width, the central part of which is from the main meridional curve is penetrated in the middle and the two outer side parts consist of aspherical surfaces with such a curvature, that there the main axes of astigmatism lie in vertical and horizontal planes, especially according to patent application P 24 39 127.3-51, and a method for producing the same.

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Postal checking account Munich No. 948 54-807 Reuschelbank Munich (BLZ 700 303 00) Account No. 423.11343 Telex 5215145 Zeus telegram address / Cable Address: Zeus patent

DT-OS 24 39 127 describes such a multifocal spectacle lens, at the one in the outer edge parts of a close-up viewing zone and / or in the outer edge parts of an intermediate zone between the distance viewing zone and the close viewing zone is a vertical line of the field of view when viewed through the lens, unbroken from top to bottom passes through. This constant horizontal prism effect is thereby achieves that when calculating the corresponding, refractive surface, care is taken that the points these edge parts fulfill a certain mathematical relationship.

The present invention is based on the object of a multifocal spectacle lens To create the type described above, in which it is ensured in a structurally simple manner that vertical lines when viewed through the spectacle lens for the entire field of view run through uninterrupted and the height the steps between the individual viewing zones can be kept within cosmetically inconspicuous limits. These The object is achieved according to the invention in that the Surface of each outer side part is part of a surface of revolution contains whose axis of rotation lies in the main meridional plane and runs vertically.

Further features and special features of the invention can be found in the subclaims.

Particular advantages and details of the invention can be seen from the following description with reference to the accompanying drawings. Show it:

Fig. -1 in the left area a front view of an inventive Multifocal spectacle lenses, the one shown along the main meridional plane in the right part of the figure Has refractive power behavior in which the transition zone and the close-up viewing zone laterally into several areas are divided, so that in the best case a normal

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Distortion occurs and the dividing lines of the zones can be cosmetically fused.

Fig. 2 An image of a square network which, when viewed by means of the multifocal spectacle lens according to the invention arises.

3 shows a front view of a further exemplary embodiment of a multifocal spectacle lens according to the invention, where the boundaries between the individual partial areas of the intermediate zone and the remote viewing zone In contrast to the multifocal spectacle lens shown in FIG. 1, they curve outwards.

4 shows a front view of a multifocal spectacle lens according to the invention corresponding to Fig. 2, in which the steps between the individual viewing zones with one another are fused, so that a cosmetically perfect impression is created.

Fig. 5 A perspective view of an inventive Spectacle lens in which the surfaces of the outer side parts are formed by parts of a surface of revolution are.

Fig. 6 A front view of a mold or a Block for the production of multifocal spectacle lenses according to the invention and a right-angled coordinate system, which is used to calculate and specify the concave surface of the block or mold.

7 shows a front view of a further embodiment of a multifocal spectacle lens according to the invention or a corresponding block or a corresponding casting mold for producing these spectacle lenses.

Fig. 8 A numerical example for the surface shape of a such a block which is used to produce a casting mold, by means of which multifocal spectacle lenses can be cast, the structure of which corresponds to FIG.

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Fig. 9 "" A schematic representation of a symmetrical Multifocal lens that is twisted around Io from the vertical, around which when looking at close interpupillary distance to allow for close objects "

1o a schematic representation of a pair according to the invention Multifocal lenses that compensate for the meridional rotation Main curve by 10 ° inclined distortion has been made.

In the case of a conventional multifocal spectacle lens such as In the case of a trifocal lens, the dividing lines between the different viewing zones are that means between the distance vision zone and the as Transitional part of the intermediate zone as well as between the intermediate zone and the close-up zone are clearly visible. This is due to the fact that steps form at the dividing lines that are square in height with the distance increase from the center of the main meridional line. The step height is, for example, on the main meridional curve equal to zero, whereas it has a height of 1.24 mm at a distance of 3 5 mm from the main meridional curve, if the difference in the vertex power between the adjacent zones is 1, o D. A step of this height is very noticeable and cannot be completely hidden by any of the known methods. With the invention, however, one possibility is created for such a cultifocal spectacle lens, the theoretical one To limit the step height to a minimum value in the course of the suction molding process described in more detail below can be merged.

An example of such a multifocal spectacle lens is shown in

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1 shows a trifocal spectacle lens 1. It consists of three in the direction of the vertical meridional main curve 2 on top of one another following viewing zones 4, 6 and 8. The lens is symmetrical with respect to the main vertical meridional curve 2. The upper viewing zone serving as a distance viewing zone 4 has a constant vertex power. The intermediate zone 6 below and the one at the lower end of the The close-up viewing zone 8 lying in front of the spectacle lenses also have constant vertex refractive powers in their central parts, with this from the distance vision zone 4 via the intermediate zone 6 to the Close observation zone 8, corresponding to those indicated on the right in FIG. 1 Increase diagram for the refractive power behavior. With b1 is the increase in vertex power from the viewing zone to the intermediate zone, with b2 denotes the increase in the vertex refractive power from the intermediate zone to the close-up viewing zone. the The total increase in vertex power from the distance viewing zone to the near viewing zone is referred to as the "Add" value B, where the relationship is:

B = b ₁ + b ₂ .

(If b .. or b ₂ = O, the trifocal lens changes into a simple bifocal lens.)

The spectacle lens 1 consists of an optical material that has a uniform refractive index, e.g. optical glass or a clear plastic such as a methyl methacrylate, a polycarbonate or CR-3 9, an allyl diglycol carbonate. For achieving the multifocal effect of the spectacle lens its front surface, which has a convex curvature, is generally used. The main reason for this The choice is that common grinding and polishing machines are designed to be spherical or toroidal surface according to the prescription for the special glasses wearer on the concave back of the glasses

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Generate lenglasses. It is therefore assumed in the following that the refractive surface of interest is on the front surface of the lens, although this is not an inevitable feature.

The size of the power differences between the individual Viewing zones, i.e. the "Add" value of the lens, can vary considerably and depends on the ability of the glasses wearer to accommodate. Also the Height h of the intermediate zone and the distribution of the "Add" value to the various jump points between the individual ones Viewing zones, as well as the number of these, can vary.

The intermediate zone 6 and the close-up viewing zone 8 are laterally subdivided into five partial areas, at least in a three-way manner according to FIGS. 1 and 3. The dividing or delimiting lines of these parts of the various viewing zones AB and CD or A'B 'and C * D' are chosen arbitrarily with regard to shape and position. In the drawings, these dividing lines are shown symmetrically with respect to the main meridional curve 2. However, this is not essential. In the embodiments shown in FIGS. 1 and 3, the lines A 'B * or. C * D 'is a mirror image of the lines AB and CD, based on the main meridional curve 2. The central area ABB * A * is thus symmetrical to the vertical main meridional curve 2 and "consists of 2 superimposed middle parts, one of which is tC F' FA ? u the intermediate

/ TO.

zone that belongs to the other F 'B' BF'- the close-up viewing zone and these central parts constant vertex power accordingly the diagram shown on the right in FIG Surface parts ACDB and a'c'd'b 'which are aspherical are and have the task of eliminating discontinuities in the surface to avoid the between the middle parts A B B'A 'and the

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outer side parts CDE or C D'e 'could arise. The width of these intermediate parts is different and can be zero in the limiting case. The regions CDE and C d'e 'of the intermediate zone and the close-up viewing zone, which are located at the edge and are referred to as outer surface parts, are formed from parts of a surface of revolution whose axis of rotation lies in the main meridional plane and runs vertically. In these outer parts of the intermediate zone and the close-up viewing zone, a vertical line of the field of vision appears as an unbroken vertical line from the top to the bottom when viewed through the multifocal spectacle lens. This means that the horizontal prism effect is constant for a vertical line lying close to the edge of the spectacle lens.

The above-mentioned condition that a vertical line runs over the edge of the spectacle lens without any cracks, is equivalent to a correction for skewed distortion.

It is useful to describe the distortion of a refractive surface by the image that one looks at a square network is given by this area. This test is, if not completely, right good approximation, the optical impression again that of the glasses wearer with such a lens.

A distinction is made between two types of distortion, normal and oblique distortion. The normal distortion corresponds to a different image magnification in two mutually perpendicular directions parallel to the lines of the network. The oblique distortion corresponds to a deviation from the orthogonality of the original grid lines. The oblique distortion is considerably more objectionable with spectacle lenses than the normal distortion. The slope Distortion is caused by the wearer of glasses

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Impression of swaying and shaking of the environment, which impairs orientation and causes discomfort.

The oblique distortion is concentrated in conventional Trifocal lenses on the areas of the horizontal steps at the various discontinuities of the vertex refractive power. An essential advantage that results from the correction of the oblique distortion at the same time is the reduction the height of the horizontal steps. These steps are not completely eliminated, the height of the steps However, it remains within the limits that are cosmetically inconspicuous and that apply to the manufacture of the spectacle lenses can be compensated by means of the suction technology described in more detail below.

In the following, a trifocal spectacle lens is considered as an example of such a correction, in which the width of the Intermediate parts ABDC and A'b'd'C 'becomes zero, i.e. at the an abrupt transition ensues.

2 shows the distortion of a square network when viewed through such a trifocal spectacle lens. It is assumed that the width of the middle part A * AB B 'is 24 mm. If the change in the vertex power at the boundary lines of the intermediate zone is 1, oo D, an edge height of 0.14 mm is obtained at a distance / y / from the main meridional plane of 12 mm. The edge height L remains constant at 0.14 mm, even if the distance IvI is greater than 12 mm. A step of such a height can still easily be determined in the spectacle lens itself. However, it is not so large that it cannot be smoothed out and made cosmetically inconspicuous when using the suction method described below. 4 shows the corresponding fusion layers which have the effect that the dividing lines are no longer visible, in contrast to conventional multifocal spectacle lenses.

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The trifocal spectacle lens shown in FIG. 3 corresponds essentially to that of FIG. 1, with only the boundary lines A B, C D and A'b ", C * D * between each part the intermediate zone and the close-up zone down outside curved and where - the boundary lines between the intermediate zone and the viewing zones adjoining it have an upward curvature, as a result of which the distance vision zone closes in the area of the main meridional curve In favor of the intermediate zone and the close-up viewing zone is reduced.

The multifocal spectacle lenses according to the invention can according to conventional processes. This production is due to the aspherical surfaces they have however difficult and expensive, since an exact and precise device for its manufacture for each type of spectacle lens necessary is. However, these disadvantages can be avoided by following the procedure described below used. In this case, a numerically controllable grinding machine is first programmed in such a way that it becomes one of the grinding machines Surface complementary, porous, ceramic block manufactures. A highly polished pane of glass is heated and pressed into the cavity of the ceramic block, on the back of the block a negative pressure is applied. This glass pane can then be polished in order to directly place the to obtain refractive surface. However, it is also possible to have the other side not in contact with the ceramic block To use a pane of glass as a casting mold for the production of plastic spectacle lenses.

As glass, which in the manner described above on the ceramic Block is placed, for example, an ophthalmic crown glass can be used. The one provided with the glass plate Ceramic block is then placed in an oven, which over a period of approximately 4 hours a maximum temperature of approximately 654 ° C (121o ° F)

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is heated. The temperature in the oven is then held at this value for approximately one hour. Then over a period of time of approximately 8 hours the furnace is cooled down from the stated temperature.

The production of the multifocal spectacle lenses according to the invention by means of the prescribed casting technique is essential Advantage that it can be used to produce spectacle lenses, which correspond in price to the previously manufactured glass spectacle lenses. Another advantage is that the finite thickness of the pane of glass when it is pressed into the ceramic block, local discontinuities are compensated for, as they arise, for example, between successive cuts of the machine's grinding tool. That The resulting spectacle lens then has an optically smooth, refractive surface of high quality.

In order to manufacture the multifocal spectacle lenses according to the invention, it is therefore necessary to first examine the surface of the ceramic block and thus determine the surface of the mold and also of the finished spectacle lens, including the construction this surface is necessary.

For the correction of the edge areas, the condition must be met that these parts contain a surface of revolution whose axis runs vertically and lies in the vertical meridional plane. This means that the edge parts CDS and C ' d'e' of the refracting surface are parts of a surface of revolution whose axis LL 'runs vertically and lies in the vertical meridional plane.

In the construction of such a multifocal spectacle lens' must first of all, according to FIG. 1, the lateral subdivision lines A B, C D, A'b ', C * D' are defined. That

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The right-angled coordinate system used is shown in Fig. 6, which can be viewed as representing the concave surface of the block over that of those previously described Process the glasses are poured. The surface of the block, the shape of which is defined by the height ζ above the x-y-plane, runs tangential to the x-y-plane in the coordinate origin 0.

The area of the block, which corresponds to the distance vision zone of the casting mold of the spectacle lens, lies above the xz plane. Those areas which correspond to the intermediate zone and the close-up zone are below this level. The intermediate zone has a height h. The block is symmetrical about the xz plane, which is the meridional plane. In the lower half of the block, the intermediate parts serving to merge are bounded on the right and left by curves which are expressed by the relationships y = y ₁ (x) and y ^ (x). The radii of curvature for the distance viewing zone, the intermediate zone and the close viewing zone are r _D , r and r.

Since the edge parts, i.e. the outermost parts of the intermediate zone and the close-up zone, are parts of a surface of revolution, the lateral intermediate parts, which serve to fuse, are designed in such a way that the smoothest possible connection is made between the middle part and the outer edge parts. The outer edge parts are then through a Rotation of the limiting curves C D and C'D 'around the axis of rotation L L * obtained from Fig. 1.

In the following, general equations are to be given which are used for the construction of the multifocal spectacle lens according to the invention or a corresponding block can be used.

The following relationship is obtained for the spherical distance vision zone, which occupies the upper half of the block and the spectacle lens:

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-12-

- ^fr D ² -U ² - y ²⁾ V2

For the middle part of the intermediate zone one obtains

(I)

Z = f

01 (X)

T ₁ - Cr ₁ - (r ^ -y ² ) " ²

For the outer edge parts of the intermediate zone results

(D

Z = f ₂₃ (χ)

(r _D -

- Y '

"1/2.

wherein

^Z 2 =

For the lateral intermediate parts of the intermediate zone that serve to fuse, one obtains

(I)
Z = f ₁₂ (x, Y)

Bf Bf

^(I) ₂₃

whereby

A = a (Y ₂ -Y) ³ + b (Y ₂ -Y) ⁴ + C (Y ₂ -Y) ⁵ ,

B =

+ b (YY ₁ ) ⁴ + c (YY ₁ j ⁵ ^

For the spherical central part the close-up viewing zone is given man

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Z = fW (χ, Y)

-ρΒ, ^ 2.

■ R

χ -

- ■■ - ■ ι

2 2

- ν

1/2

For the outer edge parts of the close-up viewing zone results

(R) Z = f ₂₃ (χ, γ)

(r _D -Z ₂ ) ² + Y ₂ ² - Y ²

1/2

with
Z ₂ = f

l / i -i \

² \ Fr ^r oj

For the lateral intermediate parts of the close-up viewing zone that serve to merge, this results

Z - f

^Δ ~ ^r

12 (χ, Υ)

= A f ^(R) + B f ^{(R) A r} Ol ^{+ B £} 23

_w o A and B have the meaning given above.

The following is a simpler but less precise set of equations for the surface.

The equation for the spherical distance vision zone is the same as above.

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For the lower half of the block results

Z = f (x, Y) = w -

in which the following is to be used for the intermediate zone:

r = r-j.

u. = 0

(yv) ² = y ² middle part

1/2

= Y ² - (1 -) / '(YY.,) ² lateral intermediate part D

2 r

= y - (1- ^) (y ² - _n ') edge part ^r D

For the close-up viewing zone, the above formulas are to use the following values

^r = ^r R u = h (1- ^ R)

(yv) ² = y ² middle part

' (Y ~ Yj) lateral intermediate part

= y ² - ilA) (y ² -ή ') ■ _{P | lndtAil} D

In the above equations, mean

h = height of the intermediate zone

⁷ '= Y ₂ / (Y ₂ -Y- \)

n '=

Y ₁ =

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The following numerical example relates to the production of a bifocal spectacle lens from the material CR ~ 39 by casting in a glass mold that is formed by sucking a glass blank onto a corresponding ceramic block. The glass blank used for this purpose is a M _e niskus Swept refractive powers of 6.00 D + and - 6.37 D, and with a center thickness of 4.0 mm.

The radius of the spherical distance vision zone should be 83.33 mm, the increase in the vertex refractive power to the close view tation zone 2.00 D. For the production of the CR-39 bifocal lens with the desired optical properties you need a block with the following radii:

r _D = 88,113 mm rj. = 68,440 mm r _R = 68,440 mm

The course of the boundary line ^ y .. and y _? of the intermediate parts is shown in FIG. They are composed of sections of straight lines that are defined by the following coordinate points:

(mm) y., (mm) y _o (mm)

0 8th I.
0 0 0 .0 6th 6th 14th 5 14th .0 13th 17th 28

The equations for the lines y ₁ and y ₂ are obtained

^y 1 = 2.O6X (mm)

= 0.51X +10.58 (mm) ) (Ζβ.

Y ₂ = 2.O6X (mm) _{for all χ}

The height = h is 6.8 mm.

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The above numerical values of r _D , r ^., R _R , h, y. and y ₂ were input to an electronic computer which, using the simplified equations above, calculated the elevation Z up to the block having a diameter of 86 mm at intervals of 4 mm. The corresponding data are plotted in FIG. 8, only half of the block being shown since the other half is a mirror image of it. Each number gives the distance in the Z direction from the surface of the block to the xy plane, which is tangential to the surface of the block at the center of the number marked 0.0000. The exact location above the respective values is in the middle of the individual numbers.

So far only spectacle lenses have been discussed which are symmetrical with respect to the main vertical meridional plane. From the point of view of storage, such complete symmetry of the lenses is very important because with Appropriate marking can be a symmetrical lens blank both as a lens for the right, as well as for the left eye can be used. From a functional point of view, however, it is preferable to use different lenses for to make the left and right eyes. Which then The resulting lenses are asymmetrical and take into account the fact that the interpupillary distance of the human With a change in accommodation from distant Objects to close objects. Therefore, when fitting symmetrical lenses for a patient, the meridional Main curve of symmetry be inclined by about 10 ° with respect to the vertical in order to provide a for the close-up viewing zone to have an effective target. This twisting of the lens around 10 ° around the center of the glass has such an effect that the direction of vision always corresponds to the main vertical meridional curve Contemplation of objects of all distances interspersed.

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However, when the lens is rotated, the major axes of astigmatism in the peripheral part of the lens are symmetrical in lens corrected for skew distortion no longer with the horizontal and vertical direction of the Aligned field of view. Especially when it comes to spectacle lenses with higher "Add" values this lead to a disruptive oblique distortion at the edge areas of the spectacle lens. Fig. 9 shows at one Lens orientation of the major axes of astigmatism in different places when the lens is around is rotated. In order to avoid this disadvantage, the outer side parts of the intermediate zone and the close-up zone are used modified so that when the main meridional curve is inclined about 10 ° to the vertical, the main axes of the astigmatism in these side parts coincide with the horizontal or vertical direction of the field of view. The those Fusing intermediate parts are also modified so that there is a smooth optical correction between the middle parts and the outer side parts results. The distance viewing zone and the central parts of the intermediate zone, as well as the close-up viewing zone remain unchanged, as with the previously explained symmetrical construction. Fig. 10 shows the orientation of the major axes of astigmatism at various Set with a right and a left spectacle lens in which the interpupillary distance decreases consideration of nearby objects has been taken into account.

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Le

first page

Claims (16)

PATENT ADVOCATE DR. HERMANN O. TH. DiEHL-DlPLOMPHYSICIST D-8000 MÜNCHEN 19- FLÜGGENSTRASSE 17 · T E LE FO N: 0 89/17 70 61 Patent claims 1> l multifocal spectacle lens, whose one refracting surface by a raeridionale that runs free of jumps Main curve is divided into two corresponding side halves, in which the curvature of the main meridional curve varies so that one above the other at least one first and second viewing zone with different along the meridional main plane of constant vertex refractive power arise, with the second viewing zone one has constant vertex power, and the first viewing zone in the transverse direction in at least three parts of finite width is divided, of which the middle part is penetrated by the main meridional curve and the two outer ones Side parts consist of aspherical surfaces with such a curvature that there the main axes of astigmatism lie in vertical and horizontal planes, in particular according to patent application P 24 39 127.3-51, characterized in that that the surface of each outer side part contains part of a surface of revolution, its axis of rotation lies in the main meridional plane and runs vertically. 7098 14/0814 LZ 700 303 00) Account No. 423.11 iss: Zeus patent OHiOlNAL INSPECTED Postal account Munich No. 948 54-807 Reuschelbank Munich (BLZ 700 303 00) Account No. 423.11343 Telex 5215145 Zeus Telegram address / Cable address: Zeus patent 2. Multifocal spectacle lens according to claim 1, characterized in that the second viewing zone (1o4) as Far vision zone forms the burstest viewing zone. 3. Multifocal spectacle lens according to one of the preceding claims, characterized in that under the first Viewing zone (1o6) at least a third viewing zone (1o8) is attached, which in the transverse direction in at least is divided into three parts of finite width, of which the central part interspersed with the main meridional curve has a constant vertex power that is greater than the constant vertex power of the central part the overlying viewing zone (1o6) and the two outer side parts consist of aspherical surfaces, the surface of each side part being part of a Contains surface of revolution whose axis of rotation lies in the main meridional plane and runs vertically. 4.. Multifocal spectacle lens according to one of the preceding claims, characterized by such an aspherical one Curvature of the two outer side parts that the step height between the corresponding viewing zones is constant along the width of these side parts. 5. Multifocal spectacle lens according to one of the preceding claims, characterized in that additional intermediate 7 0 9 8 14/0814 Partial parts of aspherical curvature are provided between the two outer side parts and the middle part, which cause a smooth transition between the middle part and the two outer side parts. 6. Multifocal spectacle lens according to claim 5, characterized characterized in that the border lines between the middle parts and the intermediate parts and the border lines between these parts and the outer side parts are pairs of curves that continuously define the first viewing zone (1o6) and enforce the third viewing zone (1o8). 7. Multifocal spectacle lens according to claim 6, characterized characterized in that the boundary lines run parallel to the plane of the main meridian (2o2). 8. Multifocal spectacle lens according to claim 6, characterized in that the first-mentioned pair of curves is downward diverges to a lesser extent with respect to the plane of the main meridian and the second flat pair of curves diverges to a greater extent in relation to this level. 9. Multifocal spectacle lens according to one of the preceding claims, characterized in that the vertical Magnification perpendicular to the main meridional plane over the total width of the spectacle lens is equal to the vertical one Enlargement at the corresponding point on the 7 098U / 08U ridional main curve is. 10. Multifocal spectacle lens according to one of the preceding Claims, characterized in that the horizontal enlargement in the outer side parts is equal to the enlargement is in the upper distance vision zone. 11. Multifocal spectacle lens according to one of the preceding Claims, characterized in that the main meridional curve is inclined by about 10 ° with respect to the vertical. 12. Multifocal spectacle lens according to one of the preceding claims, characterized in that for the curvature of the two outermost side parts in the first or in the / at least one
the relationship between the first and third viewing zones - 0 applies, where χ and y are the coordination in the horizontal and vertical direction and f is the distance between the refracting surfaces and the x-y plane are. 13. Multifocal spectacle lens according to one of the preceding Claims, characterized in that all boundary lines between the individual zones and parts are invisible are fused together. 709814/081 4 -22- 14. A method for producing a spectacle lens according to any one of the preceding claims, characterized in that that a block of porous ceramic material complementary to the breaking surfaces is made, Apply a vacuum to the back of the screen, heat a highly polished pane of glass and insert it into the cavity of the ceramic block depresses. 15. The method according to claim 14, characterized in that that the surface that was in contact with the ceramic block is then polished. 16. The method according to claim 14, characterized in that that the surface of the glass pane that has not been in contact with the ceramic block is used as a casting mold is used for the production of plastic spectacle lenses. 7098U / 08U