FR2551968A1 - Process for manufacture of intraocular lenses starting from elements manufactured in series, and lenses resulting from this process - Google Patents

Abstract

The process consists: - in manufacturing in series, in every corrective power, plano-convex and biconvex lenses 6, in providing on their edge a shape 7 suitable for clipping onto a complementary shape, and, in every size and shape used, positioning frames 1 comprising a fastening ring 4 of a diameter equal to that of the lenses, in providing on the internal segment of this ring a shape 5 complementary to the shape 7, - in matching, on demand, the lens 6 and the frame which are required and in clipping the lens into the ring of the frame.

Description

 The present invention relates to a method for manufacturing intraocular lenses.

 At present, the intraocular lenses are positioned using handles which are either secured to the lenses, more often than not, by penetration of the handles into the material of the lens and immobilization in place, in a manner or another, either made in one piece, by machining, with the lens.

 Lenses of the second type are sometimes preferred by surgeons because there is no risk of separation between the handles and the lens.

 However, these lenses have a serious drawback which is linked to the multiple possible combinations of corrective powers for the lenses and of shapes and dimensions for the positioning handles or frames.

 Indeed, the powers depend on the needs of the patient, while the shapes and dimensions of the frames are a function of the particular cases of implantation and the personal choice of the surgeon.

 Consequently, the manufacturer must either have an impressive stock of models which constitutes an immobilization of funds which is difficult to bear, or manufacture the intraocular lenses on demand, thus imposing a long period of supply to the surgeon.

 The object of the present invention is to remedy this situation by proposing a new method of manufacturing implants which are as reliable as implants in one piece, without having the disadvantages.

To this end, the method according to the invention consists of - mass production
on the one hand, in all the corrective powers
commonly requested, plano-convex lenses and
bi-convex by providing, on their edge, a relief
suitable for snapping into a complementary relief
to hush up,
on the other hand, in all dimensions and shapes
commonly used, frameworks are positioned
ment comprising a clamping ring with a diameter
equal to that of lenses, by providing on the
internal edge of this ring a complementary relief
keep silent with that provided on the lenses, - to match, on request, the lens and the frame
desired, and - to snap the lens into the clamping ring of the
frame.

 In this way, the manufacturer can immediately supply an intraocular lens meeting the various parameters required by the surgeon, without being obliged to build an expensive stock.

 Other characteristics of the invention will emerge from the description which follows, given with reference to the appended drawing and showing the application of the invention to an intraocular lens of the KELMAN type.

On this drawing
- Figure 1 is a plan view of the frame of the
lens,
- Figure 2 is a section taken on the line II-II
of figure 1,
- Figure 3 shows, on a larger scale, the areas
cooperating lens and clamp ring
frame, and
FIG. 4 shows the same area as FIG. 3,
after snapping the lens into the ring
clamping.

 If we refer to Figures 1 and 2, we see a positioning frame 1 comprising handles 2 and 3 and a clamping ring 4. As is apparent from Figure 3, the inner edge of this ring 4 has a convex relief 5 carefully polished.

 Figure 3 also shows a lens portion 6 whose edge has a groove or concave relief 7, exact reproduction, in hollow, of the relief 5 of the ring 4. The diameter D of the ring 4, taken at the top of its relief 5, is equal to the diameter D 'of the lens taken in the hollow of its relief 7.

 The lens 6 is secured to the frame 1 by snap-fastening into the ring 4, with penetration of the relief 5 into the relief 7. The snap-fastening can be facilitated by expanding the clamping ring 4 or by retracting the lens 6, or by combining the two operations, by subjecting the ring 4 and the lens 6 respectively to suitable heat or cold sources.

 The resulting product, although in two parts, is as rigid and efficient as the one-piece KELMAN lens, it is of better optical quality and much easier to manufacture.

 It is understood that the invention can be applied to other forms of frameworks than that which has been shown and described by way of example.

Claims (2)

 1 - Method for manufacturing intraocular lenses, characterized in that it consists of - mass production  . on the one hand, in all the corrective powers  commonly requested, plano-convex lenses (6)  and bi-convex by providing, on their edge, a relief  (7) suitable for snapping into relief  complementary,  . on the other hand, in all dimensions and shapes  commonly used, frameworks are positioned  ment (1) comprising a clamping ring (4) of a  diameter D equal to that of lenses (1), in  providing on the inner edge of this ring (4) a  relief (5) complementary to that (7) provided on the  lenses (6), - to match, on request, the lens (6) and the frame  (1) desired, and - to snap the lens (6) into the clamping ring  (4) of the frame (1).  2 - Intraocular lens resulting from the process according to the  claim 1.