contact lenses with holes

Abstract

An apparatus, system, process, and method for making a perforated contact lens, and the contact lens produced thereby. A first mold having a first protruding boss and a second mold having a second protruding boss are engaged with a lens-forming material contained in a mold cavity between the first and second molds. The first and second bosses abut each other in the mold cavity between the first and second molds to form a hole through the lens when the lens material is cured. The interface between the first and second bosses can be located at an intermediate position within the mold cavity between the first and second molds, so that any surface irregularities are located in the interior of the lens rather than on the outer lens surface.

Description

[Technical Field]

[0001] The present invention relates generally to the field of contact lenses, and more particularly to devices, systems, processes and methods for creating holes in contact lenses and the perforated contact lenses formed thereby. [Background technology]

[0002] Contact lenses with holes or openings that form a passageway through the lens between the base curve or back side and the front curve or front side of the lens allow fluid to move through the lens and between the two sides of the lens. Fluid movement can help prevent deformation of the lens, which can cause discomfort to the wearer, and / or prevent suction between the lens and the eye, which can hinder or prevent removal of the lens from the eye.

[0003] Previously, contact lenses with holes were manufactured by milling or drilling holes into the lens after the lens was molded, lathed, or otherwise formed. Adding holes after the lens was formed may not be practical for mass production or may result in slower production than would otherwise be desirable. It has also been found that in some cases, forming holes through the lens can leave excess material or burrs on the lens, creating surface irregularities that can cause discomfort to the lens wearer due to contact with the surface irregularities on the inner surface of the cornea or eyelid.

[0004] It can therefore be seen that there is a need for improved devices, systems, processes and methods for creating holes in contact lenses and improved contact lenses formed thereby.

[0005] It is to meet these and other needs that the present invention is primarily directed to providing improved devices, systems, processes and methods for creating holes in contact lenses and the contact lenses formed thereby. Summary of the Invention [Means for solving the problem]

[0006] In exemplary embodiments, the present invention provides improved systems and methods for manufacturing contact lenses with holes. In further exemplary embodiments, the present invention provides improved contact lenses with holes. Some exemplary applications of the present invention may enable high-speed or high-volume manufacturing of lenses with holes, for example, by forming the holes as part of the lens molding process rather than as a separate step of milling or drilling the holes into a previously formed lens. Additionally, exemplary embodiments provide lenses with holes that are free of burrs or other significant lens surface irregularities at or around the holes.

[0007] An exemplary contact lens is formed by molding in a lens mold having a first mold part with a first boss and a second mold part with a second boss. When the first and second mold parts are pressed together, the first and second bosses abut to form a through-hole in the lens. In an exemplary embodiment, the bosses have different widths or contact surface areas, such that one width or contact surface area of ​​the boss is substantially larger than the other width or contact surface area. The different sizes allow the two bosses to abut against each other even when there is relative translation, rotation, or other positional shift or variation between the two mold parts. In addition, because the two bosses each project outward from the lens-forming surfaces of their respective mold parts into the mold cavity, the contact surfaces of the bosses abut against each other during the molding process at a location inside the lens (i.e., within the hole passage, inside the lens thickness), rather than on or around the lens-forming surface, so that any excess material or flash resulting from pinch-off of material at the contact surfaces of the bosses is inside the lens, not on the surface, where it may cause discomfort to the lens wearer. In some exemplary embodiments, a countersunk or recessed portion in at least one of the bosses may help to neatly pinch off material during the molding process and may help compensate for misalignment between the two bosses. In some exemplary embodiments, one or more of the mold sections may also have a channel portion in addition to or in place of its respective boss, thereby forming a channel in the lens.

[0008] In one aspect, the present invention relates to a system for molding a holed contact lens. The system preferably includes a first mold part having a first lens-forming mold surface, a second mold part having a second lens-forming mold surface, and at least one hole-forming boss projecting outward from either the first or second mold part. The system is configured such that when the two mold halves are mated, they form a mold cavity in which the contact lens is shaped.

[0009] In another aspect, the present invention relates to a contact lens comprising a first surface, a second surface, and at least one hole extending through the thickness of the lens between the first and second surfaces. The hole preferably comprises a first hole portion and a second hole portion. The first hole portion preferably has a first lateral dimension and the second hole portion has a second lateral dimension, and the transition between the first and second hole portions is preferably located within the lens between the first and second surfaces.

[0010] In yet another aspect, the invention relates to a lens having at least one hole formed by a process including providing a first mold part including at least one first raised protrusion, providing a second mold part, supplying a lens-forming material to at least one of the first and second mold parts, and engaging the first and second mold parts together to define a lens-forming cavity between the first and second mold parts, wherein the lens-forming material is preferably cured to form the lens, with the first raised protrusion extending through the thickness of the lens to form a hole extending through the lens.

[0011] In yet another aspect, the invention relates to a method of making a contact lens, the method preferably including providing a first mold part having at least a first raised protrusion, providing a second mold part, providing lens material between the first and second mold parts, and engaging the first and second mold parts together while the lens material is between the first and second mold parts, whereby the first raised protrusion forms a hole in a contact lens formed therein.

[0012] These and other aspects, features, and advantages of the present invention will be understood with reference to the drawings and detailed description herein and will be realized by means of the various elements and combinations particularly pointed out in the appended claims. It is to be understood that the foregoing summary and the following brief description of the drawings and detailed description of exemplary embodiments are descriptions of exemplary embodiments of the invention as claimed, and are not limiting of the invention. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a front perspective view of a contact lens having a hole according to an exemplary embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of the contact lens of FIG. 1. [Figures 3A-3E] (collectively FIG. 3) illustrates a sequence for forming a perforated contact lens, according to an exemplary embodiment of the present invention. [Figure 3A] 1 illustrates a first step in an exemplary process for making a contact lens with a hole. [Figure 3B] 1 illustrates a second step in an exemplary process for making a contact lens with a hole. [Figure 3C] 1 illustrates a third step in an exemplary process for making a contact lens with a hole. [Figure 3D] 10 illustrates a fourth step in an exemplary process for making a contact lens with a hole. [Figure 3E] 10 illustrates a fifth step in an exemplary process for making a contact lens with a hole. [Figure 4] 1 is an enlarged cross-sectional view of a portion of a boss interface of a mold set used to make a contact lens having a hole, according to an exemplary embodiment of the present invention. [Figure 5] 10 is an enlarged cross-sectional view of another boss interface portion of a mold set used to make contact lenses having holes, according to an exemplary embodiment of the present invention. [Figure 6]FIG. 10 is an enlarged cross-sectional view of yet another boss interface portion of a mold set used to make contact lenses having holes, according to an exemplary embodiment of the present invention. [Figure 7] 10A-10C are enlarged cross-sectional views of different boss interface portions of a mold set used to make contact lenses having holes, according to exemplary embodiments of the present invention. [Figure 8A] 10 is an enlarged cross-sectional view of a further boss interface portion of a mold set used to make a contact lens having a hole, according to an exemplary embodiment of the present invention. [Figure 8B] 10 is an enlarged cross-sectional view of a further boss interface portion of a mold set used to make a contact lens having a hole, according to an exemplary embodiment of the present invention. [Figure 9] 10A-10C are enlarged cross-sectional views of different boss interface portions of a mold set used to make contact lenses having holes, according to exemplary embodiments of the present invention. [Figure 10] 10 is an enlarged cross-sectional view of a further boss interface portion of a mold set used to make a contact lens having a hole, according to an exemplary embodiment of the present invention. [Figure 11] 1 is a top view of the mating areas of the bosses of two mold halves used to make a contact lens having a hole, according to an exemplary embodiment of the present invention. [Figure 12] 10 is a top view of the mating areas of bosses of another set of two mold halves used to make contact lenses having holes, according to an exemplary embodiment of the present invention. [Figure 13] 10 is a top view of the mating areas of bosses of another set of two mold halves used to make contact lenses having holes, according to an exemplary embodiment of the present invention. [Figure 14] 1 is an enlarged cross-sectional view of a portion of a boss interface of a mold set used to make a contact lens having a hole, according to an exemplary embodiment of the present invention. [Figure 15] 10 is an enlarged cross-sectional view of another boss interface portion of a mold set used to make contact lenses having holes, according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention may be more readily understood by reference to the following detailed description of exemplary embodiments, taken in conjunction with the accompanying drawings, which form a part of this disclosure. It is to be understood that the present invention is not limited to the specific devices, methods, conditions, or parameters described and / or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only, and is not intended to limit the invention as claimed. All patents and other publications identified herein are incorporated by reference as if fully set forth herein.

[0015] As used in this specification, including the appended claims, the singular forms "a," "an," and "the" include the plural unless the context clearly dictates otherwise, and references to a particular numerical value include at least that particular value. Ranges may be expressed herein as from "about" or "approximately" one particular value and / or to "about" or "approximately" another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values ​​are expressed as approximations by use of the antecedent "about," it will be understood that the particular value forms another embodiment. Any use of the terms "about," "approximately," "substantially," and / or "nearly" is intended to mean an approximation that would be understood by one of ordinary skill in the art to be sufficiently close to the exact value or characteristic, based on the exact value or characteristic indicated and the context of the intended use and application. Furthermore, any method described herein is not intended to be limited to the sequence of steps described, and may be practiced in other sequences unless expressly stated otherwise herein.

[0016] Referring now to the drawings, in which like reference numerals represent corresponding parts throughout the several views, FIGS. 1 and 2 show an exemplary perforated contact lens 100 produced by a molding process according to an exemplary embodiment of the present invention. The lens 100 includes a first lens portion 101, a second lens portion 102, and a perforation 103 in the form of an opening that forms a fluid-transmitting channel or passageway through the thickness of the lens body and extends from one side of the lens to the other. The first lens portion 101 is generally hemispherical and has a first lens portion inner surface 108 and a first lens portion outer surface 109. The second lens portion 102 is also generally hemispherical and has a second lens portion inner surface 106 and a second lens portion outer surface 107. The second lens portion 102 is integrally formed with the first lens portion 101 such that the first lens portion 101 generally surrounds and surrounds the periphery of the second lens portion 102. The first lens portion 101 has a first curvature and the second lens portion has a second curvature that is generally steeper than the first curvature. In other embodiments, the first and second lens portions may have the same curvature. In further embodiments, the lens may or may not have multiple distinct lens portions or multiple curvatures. In still further embodiments, the lens may have three or more portions or distinct curvatures.

[0017] When a human or animal user wears the lens in its intended manner, the concave back or posterior surface of the lens 100 that contacts or faces the surface of the eye may be referred to as the base curve of the lens and may include inner surfaces 106, 108. The opposite convex front surface of the lens that faces away from the eye and may be contacted by the inner surface of the user's eyelid when blinking or closing the eye may be referred to as the front curve of the lens and may include outer surfaces 107, 109. Holes 103 in the lens 100 allow fluid (e.g., tears, air, eye drops, etc.) to flow between the outer surface 107 and the inner surface 106 of the lens 100. The movement of fluid from one side of the lens to the other may help prevent the lens from deforming or becoming trapped due to adhesion to the user's eye. Furthermore, the movement of fluid may allow the lens to be in two or more states, allowing for modifications to the user's tear film, better oxygen permeability, and improved wearer comfort.

[0018] In the exemplary embodiment shown in FIGS. 1 and 2, the hole 103 extends between the outer surface 107 and the inner surface 106 of the second lens portion 102 of the lens 100. The hole 103 in the illustrated embodiment 100 has a first hole portion 104 and a second hole portion 105. In this illustrated embodiment, the first hole portion 104 has a smaller lateral dimension or diameter than the second hole portion 105. In other embodiments, the first hole portion 104 may have a larger diameter than the second hole portion 105. In other embodiments, the hole portions 104 and 105 may be the same size or approximately the same size. In still further embodiments, there may be only one hole portion, or there may be three or more hole portions. In some specific exemplary embodiments, the inner diameter or width of the hole may be between about 0.010 mm and about 0.700 mm. In other embodiments, the inner diameter or width of the hole may be between about 0.050 mm and about 0.300 mm. In different embodiments, the holes may have larger or smaller widths.

[0019] 1 and 2, the hole 103 is located in the second lens portion 102. In alternative embodiments, the hole 103 may be located in other portions of the lens. For example, in some embodiments, the hole 103 may be located only on the first lens portion 101. In other embodiments, the hole 103 may be located on other lens portions not described herein. In further embodiments, the hole may be located on multiple portions of the lens 100.

[0020] 3 illustrates steps in a method of making a contact lens having one or more holes extending through it, for example, a high-speed double-sided molding process in which the holes are formed in the lens in situ as part of the molding process, without requiring a separate milling or drilling process to form the holes, according to an exemplary embodiment of the invention. As shown in the cross-sectional view of FIG. 3A, a second mold section or mold half 330 of the lens-forming mold system includes one or more second protrusions or bosses 331 that extend or protrude outward a distance from a concave front curve lens-forming surface 332 of the second mold section 310. As shown in FIG. 3B, a dose of liquid lens-forming material 360 is then deposited into the second mold section 330. The lens-forming material 360 partially conforms to the shape of the second mold section 330 and partially conforms around the second bosses 331. 3C, a first mold part or mold half 310 of the lens-forming mold system is then inserted into a second mold part 330 to form a lens-forming mold cavity between the lens-forming surfaces of the first and second mold parts or mold halves, which is substantially filled with lens-forming material 300. The first mold part 310 includes one or more first protrusions or bosses 311 that extend or project outward a distance from a convex front curve lens-forming surface 312 of the first mold part 310 toward the second mold part 330 and second boss 331. The first mold part 310 and second mold part 330 are configured and positioned such that one or more cooperating pairs of first bosses 311 and second bosses 331 align with one another and the opposing contact surfaces of the corresponding first and second bosses abut or contact one another when the mold halves are engaged with one another. The lens-forming material in the mold cavity may then be hardened, for example, by light, heat, chemical, or other polymer curing process, to form a solid or gel lens 100. As shown in Figure 3D, once the lens material 360 has hardened to form the lens 300, the first mold part 310 is removed, leaving behind a first hole portion 304 of the hole 303 formed in the lens 300 and extending into the base curve of the formed lens 300. The formed lens 300 is then released from the second mold half 330.Instead, second mold half 330 is first removed, leaving second hole portion 305 of hole 303 formed in lens 300 and extending into the front curve of the formed lens 300. The formed lens 300 is then released from first mold half 310. As shown in FIG. 3E , when lens 300 is removed from second mold 330, the resulting lens includes hole 303 that extends through the thickness of the lens to form a channel for fluid communication between the base curve side and the front curve side. The hole is composed of first hole portion 304, which arises from first boss 311 in the molding process, and second hole portion 305, which arises from second boss 331 in the molding process. In this way, hole 303 is formed in the lens in situ as part of the lens forming or molding process, and does not require a separate milling or drilling process to form the hole after the lens is formed.

[0021] Also, in the exemplary embodiment, the first boss 311 and the second boss 331 meet and abut within or inside the thickness of the lens-forming material 360 and the lens 300 in the mold cavity as the lens is formed, so that any burrs that may form due to the material pinch-off and demolding process are likely to be located inside the body of the lens 300, inside the hole 303 at or around the point where the first hole portion 304 and the second hole portion 305 meet, rather than on the inner surface 308 or outer surface 309 of the outer surface of the lens. This minimizes or eliminates the risk of any potential burrs or other surface irregularities contacting a patient's or wearer's eye and causing discomfort when the lens is in use.

[0022] In alternative embodiments, the steps described above may be performed in a different order, and it will be understood that methods and processes according to various exemplary embodiments of this invention are not limited to any particular sequence or order of steps. For example, the mold halves may be engaged before the liquid-forming lens material is inserted into the cavity between the mold halves. In another example, the liquid-forming lens material may first be applied to the mold halves that form the base curve of the lens, and then the mold halves that form the front curve of the lens may be engaged. It will be understood by those skilled in the art that variations on the above steps are contemplated by this disclosure.

[0023] In some embodiments, the hole is formed by at least one boss in either the first or second mold part that extends between the two mold parts through the thickness of the resulting lens. In certain embodiments, the hole may be formed by a combination of an abutting boss, such as in the embodiment shown in Figure 3, and a boss that extends between the two mold parts through the thickness of the resulting lens, as described below with reference to Figures 14 and 15.

[0024] FIG. 4 shows an enlarged cross-sectional view of a first mold half 410 and a second mold half 430 according to an exemplary embodiment of the present invention. The first mold 410 includes at least one first boss 411, which is further comprised of a concave contact surface or dish 415, a periphery 416, and a first sidewall 417. The second mold 430 is comprised of a second boss 431, which is further comprised of a mating surface 435 and a second wall 437. In the exemplary embodiment of FIG. 4, the first mold 410 forms the base curve or back surface of the lens, i.e., the surface of the lens that contacts or faces the eye when worn in the intended manner, and the second mold 430 forms the front curve or front surface of the lens that is farthest from the wearer's eye during use. The first boss 411 extends outward from the surface of the first mold half 410 toward the second mold half 430 and second boss 431 within the lens forming cavity when the mold halves are engaged. The second boss 431 extends outward from the second mold half 430 toward the first mold half 410 and first boss 411 within the lens forming cavity when the mold halves are engaged. The molds and boss are designed so that when the first mold half 410 and second mold halves 430 are pressed or engaged together, the contact surface or edge of the first boss 411 contacts and abuts the mating surface 437 of the second boss 431. The location where the first boss 411 and second boss 431 abut is between the first mold 410 and second mold 430, within the interior region of the lens forming cavity formed between the mold halves, and therefore between the inside of the lens body and the inner and outer surfaces of the resulting lens.

[0025] In the embodiment shown in FIG. 4 , the diameter and / or width of the first boss 411 at the edge 416 is smaller than the diameter and / or width of the second boss 431 at the mating surface 435. The size difference helps compensate for any translational movement between the first boss 411 and the second boss 430 when the first mold 410 and the second mold 430 are pressed together. For example, the first mold 410 can translate slightly to the right relative to the second mold 430, and the edge 416 of the first boss 411 can still abut and be surrounded by the mating surface 435 of the second boss 431. The size difference also helps compensate for dimensional casting errors in forming the mold.

[0026] The dish 415 of the first boss 411 on the first mold 410 captures crushed lens material when the first boss 410 is inserted into the lens material, such as during the process shown in FIG. 3. The wall of the dish 415 is at an angle θ with respect to the plane formed by the mating surface 435. In other embodiments, the angle θ can be between about 0° and about 50°. In other embodiments, the angle θ can be between about 10° and about 40°. A larger dish angle allows for greater edge crushing by the first boss 411 and greater misalignment between the first boss 411 and the second boss 431.

[0027] In an exemplary embodiment, the hole-forming bosses are generally symmetrical about a central axis parallel to the engagement path of the first and second mold halves in the lens-forming process, allowing for parallel engagement and release of the bosses as the mold halves are moved into and out of engagement. For example, in the embodiment shown in FIG. 4 , first boss 411 and second boss 431 are generally formed and aligned about a vertical axis 420 parallel to the engagement axis, and mating surface 435 is generally horizontal, as is edge 416. In other embodiments, the bosses may be oriented about a line that forms an oblique angle with or to the vertical axis or engagement axis. For example, in the embodiment shown in FIG. 5 , first boss 511 and second boss 531 are formed and aligned about local normal 525. While mating plane 535 and edge 516 are perpendicular to local normal 525, in other embodiments they may be at an oblique angle from the local normal. 5, the local normal 525 is the local normal to a second boss 530 that forms the front curve of the lens. In other embodiments, the boss may be formed about another line that is oblique to the local normal or vertical of the first type that forms the base curve of the lens.

[0028] In exemplary embodiments having at least one boss on each side of the mold, the bosses can have complementary heights such that when they abut, the bosses span the thickness of the contact lens. For example, the first boss 411 can have a first height H1, and the second boss 431 can have a second height H2. The first height H1 and the second height H2, when added together, equal the depth of the mold cavity where the first boss 411 and the second boss 431 abut. The first height H1 is preferably about 5 to about 95% of the mold cavity depth or lens thickness, and the second height H2 is the remainder of the mold cavity depth or lens thickness. In some embodiments, the first height H1 is about 30 to about 70% of the mold cavity depth or lens thickness, while H2 is the remainder of the mold cavity depth or lens thickness. For example, H1 can be approximately 50% of the mold cavity depth or lens thickness, and H2 can be approximately 50% of the mold cavity depth or lens thickness. The exact height of the boss depends on several factors, such as the angle of the boss relative to the mold and the overall thickness of the lens. In exemplary embodiments, the boss can have a height range of approximately 0.01 mm to approximately 0.3 mm. In other embodiments, the boss height range can be approximately 0.02 mm to approximately 0.2 mm. In embodiments in which the boss is oriented about a vertical line, the relative thickness of the lens seen by the boss is greater. Thus, when the mold is oriented about a vertical line, the apparent overall height of the mold is greater compared to when the mold is oriented about a local normal or other axis.

[0029] In the exemplary embodiment of FIG. 4 , the first wall 417 of the first boss 411 and the second wall 437 of the second boss 431 are generally parallel to an axis 420 that extends perpendicular to the mating surface 435 and is parallel to the path of engagement of the first and second mold halves in the lens-forming process, forming a generally cylindrical boss body. In alternative embodiments, the walls and axes may not be parallel. For example, in the embodiment shown in FIG. 5 , the first wall 517 of the first boss 511 may be angled obliquely relative to the mating surface 535 and the local normal 525, thereby tapering the first boss 511 and forming a generally frusto-conical boss body that is wider at its base where it meets the first mold half 510 than at the edge 516 where it meets the mating surface 535. Similarly, the second wall 537 of the second boss 531 can be angled so that the width of the second boss 531 is tapered at its base where it mates with the second mold 530 to be greater than at the mating surface 535. The added relative width at the base of the first and second bosses 511 and 531 and the resulting angle of the first and second walls 517 and 537 can help minimize any thin spots around the resulting lens hole. The draft angle of the angled walls 517 and 537 can also help prevent the lens from becoming stuck on the molds 510 and 530 and / or bosses 511 and 531 if the lens-forming material shrinks during curing, thereby aiding in the separation of the lens from the molds 510 and 530. In some embodiments, the angle between the wall and the axis 520 can be from about 0 degrees to about 20 degrees. In certain embodiments, the angle can be about 10 degrees.

[0030] In the embodiment shown in Figures 4 and 5, the dish or concave surface is on a boss protruding from the mold half that forms the base curve of the lens, which is the portion of the lens closest to the wearer's eye. When a dish is on a boss formed on the base curve, the feature size of the hole on the base curve of the lens can be minimized, thereby reducing the feature size that contacts the wearer's eye. In other embodiments, the boss that forms the surface of the lens farthest from the wearer's eye can have a dish, and the other boss can have a receiving surface. For example, in the embodiment shown in Figure 6, a first mold 610 again forms the base curve and a second mold 630 forms the outermost surface of the lens, but a first boss 611 on the first mold 610 has a mating surface 635, while a second boss 631 on the second mold 630 has a dish or recess 615 with a periphery 616. In the embodiment of FIG. 6, the first boss 611 has a larger diameter or lateral dimension than the second boss 631, so that the dome-shaped second boss 615 is surrounded by the mating surface 635 on the first boss 611, even if there is some lateral or rotational movement or misalignment between the two mold halves during the lens-forming process.

[0031] In some embodiments, the periphery of the dished or concave boss surface may be sharp and / or pointed, similar to edges 416, 516, and 616. In other examples, such as that of FIG. 7, the periphery 716 of the boss contact surface may be radiused, rounded, or chamfered. Additionally, the interior corner formed where the boss meets the base of the mold section may be radiused or rounded, as seen in FIG. 7. The corner formed between the boss and the mold section may have a radius of about 0 mm to about 0.150 mm. In certain embodiments, the corner may have a radius of about 0.005 to 0.050 mm.

[0032] In some embodiments, one or both of the mold sections may include a channel instead of or in addition to a boss. For example, in the embodiment of FIG. 8A, the second mold half or section 830 has a channel-forming protrusion 840 that forms a recess in the resulting lens. In the particular embodiment of FIG. 8A, the first boss 811 mates with the channel to create a hole that extends from the outer surface of the lens (e.g., surface 107 in FIGS. 1 and 2) until it mates with the channel to create a hole that extends from the outer surface of the lens (e.g., surface 109 in FIGS. 1 and 2) until it mates with the channel to create a hole that extends from the outer surface of the lens (e.g., surface 109 in FIGS. 1 and 2) until it mates with the channel to create a hole that mates with the hole that mates with the hole that mates with the channel 840 in the thickness of the resulting lens. In other embodiments, such as the one shown in FIG. 9, the channel 940 may have a boss 911 extending from the channel. In embodiments where a boss extends from a channel, the smaller boss can be on either the first boss or the second mold part, as long as the other boss is wider. In some embodiments, both mold parts can include a channel and a boss, whereby a channel is formed on either side of the lens and a hole traverses the channel.

[0033] In some embodiments, one of the bosses may be generally dome-shaped or hemispherical, while the other boss may be of generally smaller dimensions. For example, in the embodiment shown in FIG. 10 , the first mold 1010 has a dome-shaped boss 1050 that projects outward from the first mold 1010 toward the second mold 1030 and second boss 1031. The second boss 1031 on the second mold 103 includes a dish or recess 1035 with a periphery 1036 and a wall 1037. In an alternative embodiment, the dome-shaped boss may be on the mold that forms the outer surface of the resulting lens, and the smaller boss may be on the mold that forms the base curve of the lens. The present invention also includes exemplary embodiments in which one or more hole-forming bosses or one or more protrusions are provided on only one or other of the first and second lens halves and are configured to abut or contact the lens-forming surface of the other mold half and extend the entire thickness of the mold cavity to form a hole through the lens during the molding process. In such embodiments, the bosses or protrusions may optionally be shaped or otherwise configured to minimize or eliminate any surface irregularities on the outer lens surface, or the lens may be further processed to remove any surface irregularities to improve wearer comfort.

[0034] In some exemplary embodiments, one or both of the bosses have a generally circular shape in plan view. For example, FIG. 11 shows a top view of an embodiment in which the second boss 1131 has a circular, flat mating surface 1135. The periphery 1116 of the smaller, first boss (not shown) forms a small, circular footprint configured to be surrounded within and generally coaxially aligned with the circular mating surface 1135 of the larger boss when the mold halves are engaged. In other embodiments, the larger boss may have an oval shape in plan view. For example, FIG. 12 shows a top view of an embodiment in which the second boss 1231 has an oval mating surface 1235. In this embodiment, the edge 1216 of the smaller, first boss (not shown) forms a smaller, circular footprint within the oval mating surface 1235. In still further embodiments, the larger boss may have a square, rectangular, or other shape in plan view. For example, FIG. 13 shows a top view of an embodiment in which the second boss 1331 has a rectangular mating surface 1335. In this embodiment, the edge 1316 of the smaller first boss (not shown) forms a smaller circular footprint within the rectangular mating surface 1335. In other embodiments, there can alternatively or additionally be a smaller boss. In other embodiments, the smaller boss can alternatively or additionally have an oval or rectangular shape. In some examples, the shape of one or both bosses can be other than oval, rectangular, or circular, so long as one dimension of the boss is sufficiently smaller than the other to allow for and compensate for translation or tolerances in the alignment or relative positioning between the two molds. In an exemplary embodiment, the larger boss can have an arcuate form in plan view, defining an annular segment at a radial position corresponding to that of the smaller boss, so that if the mold halves are slightly rotationally misaligned when engaged in the lens-forming process, the smaller boss still rests on the contact surface of the larger boss.

[0035] In some embodiments, either the first or second boss can extend the entire distance between the two mold halves such that a hole is formed by only a single mold boss. For example, in the embodiment shown in FIG. 14 , boss 1411 extends from base curve 1410 toward second mold half 1430 about local normal 1425. When mold halves 1410 and 1430 are engaged, boss 1411 traverses the distance between the two mold halves 1410 and 1430 such that edge 1416 of boss 1410 abuts second mold half 1430. In other embodiments, such as the embodiment shown in FIG. 15 , boss 1535 can extend from second mold half 1530 such that edge 1536 of boss 1535 abuts first mold half 1510 when mold halves 1510 and 1530 are engaged. In both embodiments, the bosses are shown in Figures 14 and 15 as being oriented about the local normal, however, in other embodiments where a single boss is used to form the hole, the boss may be oriented about a vertical line.

[0036] In addition, it should be understood that aspects of the various embodiments of the present invention may be substituted either in whole or in part, or may be combined and / or used together in any manner.

[0037] Although the present invention has been described with reference to exemplary embodiments, those skilled in the art will appreciate that various modifications, additions and deletions are within the scope of the invention as defined by the following claims.

Claims

1. 1. A system for molding a perforated contact lens, comprising: a first mold part having a first lens-forming mold surface; a second mold part having a second lens-forming mold surface; at least one hole-forming boss projecting outwardly a distance from either the first mold portion or the second mold portion and having a first contact surface; wherein the first and second mold parts engage to form a lens forming cavity, and wherein the at least one hole-forming boss extends between the first lens-forming mold surface and the second lens-forming mold surface when the first and second mold parts are engaged.

2. 2. The system of claim 1, wherein the at least one hole forming boss includes a first hole forming boss and a second hole forming boss, the first hole forming boss protruding outward from the first mold part and having a first contact surface, the second hole forming boss protruding outward from the second mold part and having a second contact surface, and the first and second hole forming bosses are configured to align and abut one another when the first and second mold parts are engaged.

3. the first lens-forming surface further comprises a generally convex lens base curve-forming surface; 3. The system of claim 1, wherein the second lens forming surface further comprises a generally concave lens front curve forming surface.

4. 4. The system of claim 2 or 3, wherein the first contact surface of the first hole-forming boss has a smaller lateral dimension than the second contact surface of the second hole-forming boss.

5. The system of any one of claims 1 to 4, wherein the first contact surface of the first hole-forming boss defines a dished recess surrounded by a periphery.

6. The system of claim 5 , wherein the periphery of the first contact surface is rounded.

7. The system of any one of claims 1 to 6, wherein at least one of the first and second mold parts further comprises a channel-forming protrusion that protrudes a distance outward from its lens-forming mold surface.

8. The system of claim 7 , wherein the channel-forming protrusion has an additional raised portion within the channel-forming protrusion.

9. The system of any one of claims 1 to 8, wherein the hole-forming boss comprises a generally cylindrical body having a sidewall extending generally parallel to an axis of engagement of the first and second mold parts.

10. The system of any one of claims 1 to 8, wherein at least one of the hole-forming bosses includes a generally frusto-conical body having sidewalls angled obliquely relative to the longitudinal axis.

11. The system of any one of claims 2 to 8, wherein at least one of the first and second hole-forming bosses includes a straight sidewall.

12. 9. The system of claim 2, wherein both the first and second hole-forming bosses include angled sidewalls such that each boss is wider proximal to its respective lens curving mold surface and narrower distal to its respective lens curving mold surface.

13. The system of any one of claims 2 to 8, wherein at least one of the first or second hole-forming bosses is dome-shaped.

14. 1. A method for cast molding a contact lens, comprising: Obtaining a system according to any one of claims 1 to 13; Obtaining a lens-forming material; dispensing a specified amount of the lens-forming material onto the first or second lens-forming mold surface; engaging the first and second mold parts together to form the lens-forming cavity containing the lens-forming material therein and ensuring that the at least one cavity-forming boss extends between the first lens-forming mold surface and the second lens-forming mold surface; curing the lens-forming material in the lens-forming cavity to form a perforated contact lens; A method comprising:

15. 1. A cast molded contact lens, comprising: a first surface; and a second surface; and at least one hole extending through a thickness of the lens between the first surface and the second surface, a first hole portion; A second hole portion and At least one hole further comprising: wherein the first hole portion has a first lateral dimension and the second hole portion has a second lateral dimension, and a transition between the first hole portion and the second hole portion is located within the lens between the first surface and the second surface.

16. 16. The contact lens of claim 15, wherein the first and second surfaces further comprise an outer portion and an inner portion, the outer portion surrounding the inner portion, and the at least one hole located within the inner portion of the first and second surfaces.

17. 16. The contact lens of claim 15, wherein the first and second surfaces further include outer and inner portions, and the at least one hole is located within the outer portions of the first and second surfaces.

18. 16. The contact lens of claim 15, wherein the first and second surfaces further comprise outer and inner portions, and wherein a first of the at least one hole is located within the inner portions of the first and second surfaces, and a second of the at least one hole is located within the outer portions of the first and second surfaces.

19. A contact lens according to any one of claims 15 to 18, wherein the first and second surfaces of the lens are free of any significant surface irregularities resulting from the formation of the at least one hole.

20. A contact lens according to any one of claims 15 to 18, wherein the first lateral dimension is smaller than the second lateral dimension.

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