Patent Application
20190151152
The present invention relates generally to corrective lenses employed in eyewear such as eyeglasses, protective eyewear, and goggles. More particularly, the disclosed eyewear device and method for forming such, relates to a first lens portion of optically correct material which is formed as a unitary structure with one or a plurality of rearward positioned projections formed of optically correct material, and wherein the perimeter edge of the first lens portion is configured for engagement in an eyewear frame or goggle or other lens frame, and where each projection is either pre-ground or may be subsequently ground to form a prescription lens.
Individuals with eyesight problems have turned to corrective eyewear for hundreds of years. As a general rule such eyesight problems are a result of the physical characteristics of the eye of the person requiring corrective lenses. Over the duration, such corrective lenses have been provided to users requiring them. The basic nature of grinding lenses to refocus the image captured by the eye of the user onto the receptive rear surface of their eye in a manner rendering clearer vision has progressed to provide corrections for issues other than near or far sightedness. However, the basic premise of positioning a lens in front of the eye of the user to refocus incoming light is still present today.
In some instances the nature of construction and configuration of such corrective lenses has been less than adequate. For example, users of corrective lenses who suffer from severe farsightedness require very thick lenses to be ground to correct their vision. The perimeter of such lenses being thick, severely limits the eyeglass frames which can be employed for such users due to the perimeter thickness of conventionally formed lenses. Such a thick perimeter gives the eyewear a “bottle” look due to the thick sidewall.
Further, users with nearsightedness or farsightedness who or suffering from other vision acuity problems also have problems trying to wear sport goggles for activities such as skiing or motorcycling, as well as wearing safety goggles.
This is because goggle lenses and protective lenses are conventionally formed of a curved thin optically correct material, which cannot be ground to form corrective and prescription eyewear. As a consequence, such users who must see clearly for their job or sport, have been forced to try and fit their prescription eyeglasses, rearward of the curved protective lens within the cavity of the goggle or safety goggle covering their eyes. Such users, thereafter, must view their surroundings through both the protective or goggle lens and their own lenses spaced between the goggle lens and their face. This spaced positioning of different lenses, leads to poor vision from fogging, and causes shadow images, glare problems, light refractions, and other issues which are caused by the interaction between their corrective eyeglass lenses and the goggle lens or lenses they are positioned behind. In prior art, partial solutions to the problem have been advanced. For example U.S. Pat. No. 8,814,349 (Quintana), while a leap forward in the concept of providing a single structure from corrective lenses combined with a panoramic or shielding lens, has significant shortcomings in the taught construction of the unitary structure. For example, Quintana teaches the novel concept of forming two projecting portions of lens material rising from one side of a first curved lens portion for formation of ophthalmic lenses. However, in practice the taught construction, may be prone to cracking along the perimeter of the projecting portions at their intersection with the front panoramic lens, and Quintana provides no teaching or hint on how the projecting portions can be ground to corrective lenses.
Additionally, a refraction of light through the sidewall of the projecting portions, at and adjacent their intersection with the front panoramic lens, as taught, generates refractive light issues. Light passing through the curved lens portion to this intersection can produce glare and colorized light flashes, which has been found to be distracting to users. Additionally, the dissimilar thicknesses of the panoramic lens and areas thereof with projecting portions, will cause thermal issues during formation in the manner taught, due to the retention of heat in the thicker areas.
The device and method of formation taught, therefor, provides for a corrective or prescription lens which is formed to a unitary structure in fused combination with the curved first lens portion formed of a thinner surrounding panoramic lens. The resulting unitary structure provides a combined protective and corrective lens, formed in a manner to both prevent cracking and stress fractures over time and to prevent deformation during manufacture due to temperature differentials during curing of molded optical material having thicker and thinner such optical materials.
The device and method herein provides a unitary structure formed of optical material such as polycarbonate, glass, polymers such as allyl diglycol carbonate (ADC), trivex, and other injection molded material, which is employable for protective and corrective lenses. The device yielded by the method herein is employable for frame engagement as single lenses of eyewear as well as in dual lens configurations for use with protective eyewear shields and sport and protective goggle devices. Further, it is formable in shapes which allow for formation of progressive lenses in both the horizontal and vertical direction. Still further, the disclosed lenses herein formed by the method herein, forms a unitary structure with no gaps between the front lens portion and one or a plurality of projections to the rear of the frontal panoramic lens. So formed, the projections may be ground in advance or are machinable after formation of the unitary structure, to provide corrective lenses for the user. The projections may be ground to the desired corrective and prescription lens, using conventional lens grinding machinery, in spite of the large and highly curved panoramic lens surrounding the projecting portions.
The forgoing examples of related art and limitations related therewith are intended to be illustrative and not exclusive, and they do not imply any limitations on the invention described and claimed herein. Various limitations of the related prior art will become apparent to those skilled in the art upon a reading and understanding of the specification below and the accompanying drawings.
It is an object of this invention to provide a unitary structure and method therefor, yielding a first curved or panoramic lens portion which is fused in the unitary structure with one or a plurality of projecting portions connected thereon which may be cut to form ophthalmic lenses.
It is a further object of this invention to provide such a unitary structure where the first lens portion or panoramic lens from which the projecting portion extends, surrounds and extends from the perimeter edge of the projecting portion with a thinner cross section of optical material, which may be fit to frames heretofore precluded for users with thick lens prescriptions.
It is a further object of this invention to provide the projecting portions formed upon a surface of a surrounding larger curved panoramic lens, where the projecting portions may be machined prior to or after fusing to a unitary structure, using conventional lens grinding machinery despite the large and curved first lens portions surrounding them.
It is also an object of this invention to provide the projecting portions in an engagement to the surrounding panoramic lens, in a manner to form a unitary structure with the surrounding panoramic first lens, where the perimeter edge of the projecting portions are in shapes which may be cut to allow for progressive lenses in both the horizontal and vertical directions.
These and other objects, features, and advantages of the present lens invention and system herein, as well as the advantages thereof over existing prior art, which will become apparent from the description to follow, are accomplished by the improvements described in this specification and hereinafter described in the following detailed description which fully discloses the invention, but should not be considered as placing limitations thereon.
The present invention herein provides a lens formed into a unitary structure featuring a first lens portion formed in a generally concave panoramic shape, which has at least one projecting portion defined in shape by a perimeter edge of the projecting portion which forms a rear surface of the first lens portion. So configured, the formed lens yields a unitary structure of optical material.
In the formed unitary structure of the lens herein, the cross sectional thickness of the first lens portion surrounding the projecting portion, is thinner than the cross sectional thickness of the area within the bounds of the perimeter of the projecting portion rising from a rear or first side of the first lens portion.
This first lens portion is optically correct across its entire surface such that the thinner surrounding area of the first lens portion, is optically correct and significantly thinner in cross section than the raised portion. When employed with eyeglasses, this structure allows engagement within an eyeglass frame or goggle, which is still adapted for an engagement to temple portions to form a shield.
It was unexpectedly found during experimentation with forming the lens device herein with the raised portions forming corrective lenses, that linear intersections of the perimeter of the raised portion, rather than minimizing optical refractions and light transmissions, actually caused such. Consequently, it was found that in all modes of the device herein such defects in image and light transmission could be minimized by instead curving the area of such intersections which was unexpected. As such, the intersection of the perimeter edge or sidewall which defines a shape of the projecting portion employed for lens formation, with the rear or first surface for the first lens portion, is preferably neither a perpendicular intersection of two planar surfaces nor an intersection of a straight line extending up the sidewall surface of the projecting portion.
Preferably, in all modes of the device herein, the intersection of the sidewall of the perimeter of the projecting portion, which defines a shape of the projecting portion, is preferably formed such that the line running up the sidewall surface from the intersection with the first surface of the first lens portion, is curved or non linear. Thus, in forming the unitary structure during molding, machining, or otherwise, preferably a radius or curved surface is formed where the intersecting portion of the sidewall with the first lens portion, changes direction relative to the rest of the sidewall extending to the edge of the machinable surface of the projecting portion. It has been found a radius of substantially 0.1 mm to 0.4 mm will minimize the visual refractive and other defects of the final unitary lens, with 0.3 mm being particularly preferred. Further, it was found that forming a radius at a distal end of the sidewall forming the projecting portion, during formation of the corrective lens, also yielded an improvement in the image and light transmission of the unitary structure. Thus, a curve or radius extending around the upper perimeter of the projecting portions, in the same range of substantially 0.1 mm to 0.4 mm minimized this problem and is preferred. While the noted ranges herein are preferred, by substantially is meant that a curve or radius which is plus or minus 20% of the stated range should be considered within the scope of this patent.
In all modes of the device herein, one or a plurality of the projecting portions of optical material, are formed or fused to a unitary structure with the material forming the surrounding optically correct panoramic lens. Preferably, this is accomplished by injection molding, pressure molding, machining such as with a CNC machine or the like.
It was found however that forming the projecting portions used for grinding corrective lenses, separately from the first lens portion, and then co-molding them during formation of the first lens portion, to yield a unitary structure of optical material, yielded a lens device with significantly added utility and function, rather than just forming a single unit from the optical material in one step. In this process, pre-formed projecting portions are positioned in a mold with one side thereof in communication with the cavity used to form the first lens portion. Once the heated optical material forced into the mold cavity for the first lens portion is cured by cooling, the unitary structure of the first lens portion and projecting portion can be removed from the mold.
Particularly useful was the method of forming the one or a plurality of projecting portion or portions separately and prior to formation of the injection or pressure molded first lens portion or shield. Using these pre-formed projecting lens portions, they can then be co-molded with the first lens portion forming the shield, by insertion into the mold, whereupon the material forming the lens portions is fused with the molten optical material forming the first lens portion or shield.
This method allowed for many combinations of first lens portions defining the shield, and fused projecting portions which are subsequently ground to form corrective or prescription lenses, which are not possible by forming both structures in a single pass in one mold or even by machining optical material from a block to form the unitary structure.
Further, as noted, experimentation has shown a curve or arc of the lower end of the perimeter of the sidewall of the projections at their intersection with the first lens portion yields a perimeter sidewall intersection between the projecting portion and the first lens portion, which has significant improvements in minimizing colorized light and other refractive issues. Further, experimentation found that forming the arc or curve in a particular radius range noted herein provided increased resistance to cracking and fracturing at the intersection of the two components under force or due to temperature changes the unitary lens encounters.
This curve or arc is formed preferably in a radius portion along the intersection of the sidewall around the perimeter edge of the projecting portion, where it meets the rear or first surface of the first lens portion. Such may be accomplished during co-molding by forming the projecting portions of material with the radius around the perimeter, or by forming the mold holding the formed projecting portions for fusing with the first lens portion forming the shield. As noted 0.3 mm is preferred but a range between substantially 0.1 mm to 0.4 mm works well.
Other shapes of the intersection of the perimeter edge with the first lens surface which has shown to work well to prevent fractures are an inversed curve, a slanted portion at the intersection of a sidewall and first lens portion, as well as a radius or curved recess. However, the radius formed in the annular intersection of the sidewall defining the shape of the projecting portion and the first surface of the first lens portion is a particular favorite.
As noted, the projecting portion engagement to the first lens portion may be accomplished in the method herein by forming the projecting portion or portions in a first step, and co-molding them to a unitary structure with the first lens portion.
Forming the projecting portions first allows for positioning of polarizing or other filters into the projecting portion, which is then fused to the first lens portion without the need to include the polarizing or other filter in the surrounding first lens portion. Further, the formed projecting portions can be colorized without doing the same to the first lens portion forming the shield. Additionally, while the projecting portions of the unitary structure can then be ground to the proper prescription or correction for the user, it is possible to also grind the projecting portions in advance, and then fuse them to the unitary structure with the first lens portion thus providing even more utility and options.
Still further, the shape of the projecting portion, defined by the sidewall intersecting the first surface of the first lens portion, can be formed in shapes as shown herein, or other shapes, which will allow for cutting of progressive lenses therein for the user. For example, one such shape, as shown in the figures, allows for portions of the projecting portion to extend closer to the bridge of the nose, while concurrently extending to the temple and well below the nose. This extended rectangular shape with a curve extending from a nose-side to the lower edge, allows for formation of progressive lenses which are highly customized to a user where the progressive lens can be both horizontal from top to bottom, and sideways from nose to temple. Since the surrounding section of the first lens portion is significantly thinner than the unitary portion of the projecting portion and first lens portion, the formed lens or shield can be configured for users.
Additionally shown is a removable tooling engagement member extending from the first lens portion. By formation of this tooling engagement member, in a break away or removable engagement extending perpendicular from the axis of the unitary lens and in a centered position, it allows for machining of the raised surfaces of the projecting portions to form corrective lenses, by an engagement of the unitary structure to a lens machining apparatus, using the removable projecting member. As noted, tooling engagement and the unitary structure of the first lens and projecting portion overcomes the problems associated with the prior art, where the large curved panoramic first lens portion blocks engagement in a conventional fashion to lens grinding machines. Once the projecting portion surface or surfaces have been properly machined to the corrective lens, the projecting member can be removed by breaking a frangible portion or cutting it form the side edge.
Finally, the unitary lens herein is especially well adapted to the formation of protective eyewear, as well as for sport goggles and the like. Further, because a plurality of raised portions are fused with and extend from the first surface of the first lens portion surrounding the raised portions, and the first lens portion is large and panoramic and has thin edges, the unitary structure provides a goggle which is protected from fogging and the like. Further, as noted above, a wafer or layer of any of a polarizing film or photo-chromatic material or reflective film or light filtering material, may be prepositioned within the lenses formed by the projecting portions and the first lens portion, thereby providing polarized eyewear to the user for high glare conditions.
In all modes, both the first lens portion surrounding the engaged projecting portion, and the projecting portion or portions, may be formed of polycarbonate plastic or other optically suitable polymeric or plastic materials, such as a monomer plastic, or a “High Index” plastic. The plastic or polymeric material used for both the first lens portion and the raised portions should be the same material or capable of fusing during molding to form a unitary structure which is optically correct once the projecting portions are ground to the prescription of the user. Further, in all modes of the device herein, it is preferred that the base curve of the first side of the first lens portion match that of the second opposite side, and that the thickness of the first lens portion be substantially the same from one end to the other. Currently, a base curve on both sides running from 5-9 mm is preferred with 6.8 being particularly preferred after extensive experimentation.
With respect to the above description, before explaining at least one preferred embodiment of the herein disclosed eyewear invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement of the steps in the following description or illustrated in the drawings. The unitary lens invention herein described is capable of other embodiments and of being practiced and carried out in various ways which will become obvious to those skilled in the art on reading this disclosure. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing and carrying out the present disclosed system and eyewear apparatus. It is important, therefore, that the claims be regarded as including such equivalent construction and methodology insofar as they do not depart from the spirit and scope of the present invention.
Other aspects of the present invention shall be more readily understood when considered in conjunction with the above noted accompanying drawings, and the following detailed description, neither of which should be considered limiting.
Now referring to drawings of
Extending from one side edge of the first lens portion 14 is shown a removable tooling member 20. It has been found in experimentation, that the tooling member 20 can be engaged with a grinding machine used to grind the individual projecting portions 16 to form the prescription or corrective lenses for a user.
One method of formation of the unitary structure of first lens portion 14 and projecting portions 16 is shown in
The resulting device 10 from the method of
The resulting device 10 is shown in
In
While all of the fundamental characteristics and features of corrective lens and shield in unitary structure and method have been shown and described herein, with reference to particular embodiments thereof, a latitude of modification, various changes and substitutions are intended in the foregoing disclosure and it will be apparent that in some instances, some features or steps in the invention may be employed without a corresponding use of other features or steps without departing from the scope of the invention as set forth. It should also be understood that various substitutions, modifications, and variations may be made by those skilled in the art without departing from the spirit or scope of the invention. Consequently, all such modifications and variations and substitutions are included within the scope of the invention as defined by the following claims.
This application claims priority to U.S. Provisional Patent Application, Ser. No. 62/344,787, filed on Jun. 2, 2016, which is incorporated herein in its entirety by this reference thereto.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2017/035796 | 6/2/2016 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62344787 | Jun 2016 | US |
