A contact lens

Abstract

The present disclosure relates to a contact lens that is easily rotated when worn, comprising: a vision correction zone having a first refractive power based on an eyeball prescription and located in the central region of the contact lens; and a vision control zone that surrounds the first correction zone and is annular in shape, wherein the equivalent refractive power of the vision control zone is positive compared to the first refractive power, the vision control zone including a first control zone adjacent to the first correction zone, the boundary between the first control zone and the first correction zone being a first inner edge defined by a first inner circle and a first outer circle that oscillates around the circumference of the contact lens, the diameter d1 of the first inner circle satisfying the following conditions: 2.4 mm ≤ d1 ≤ 3.6 mm, and the diameter d2 of the first outer circle satisfying the following conditions: d1 + 0.2 mm ≤ d2. The contact lens can provide different defocus stimuli over time, thereby achieving a long-term myopia control effect.

Description

Technical Field

[0001] The present disclosure relates to the field of ophthalmic devices, and more particularly to a contact lens intended to be worn in front of a person's eye to inhibit the development of eye abnormalities such as myopia or hyperopia. Background Art

[0002] Traditional contact lenses primarily aim to correct vision for eyes that already have refractive errors. These lenses are designed as a form of relief to address existing defects. However, after wearing these lenses (such as single-vision lenses), vision inevitably deteriorates (for example, myopia worsens). People prefer to actively control refractive errors (such as myopia and hyperopia) to prevent further deterioration. Therefore, new functional contact lenses, based on traditional single-vision lenses, are being developed to mitigate myopia.

[0003] The representative of the functional lens for slow control of myopia is the peripheral continuous defocus contact lens, in which the spherical refractive power of the lens periphery is higher than that of the central area of ​​the lens. Among the existing defocus lenses, the areas on the contact lens used to achieve defocus can be divided into annular defocus design (commonly known as "concentric circle" design), progressive multifocal design and scattering microlens layout design. In the concentric circle design, the surface of the contact lens is usually provided with 2-8 rings of continuous defocus areas with different refractive powers. In the progressive multifocal design, the refractive power of the contact lens changes gradually along the radial direction. In the scattering microlens layout design, the surface of the contact lens is regularly provided with microlenses with additional refractive power or special focus directions.

[0004] Evidence suggests that these concentric, progressive multifocal contact lenses can indeed achieve a certain degree of delay in controlling myopia. Following the commercialization and widespread use of these lenses, researchers and physicians have generally found that contact lenses can significantly slow the progression of myopia in patients with poor vision during their initial use (mostly one year). However, as years of contact lens wear increase, patients with poor vision gradually adapt and compensate for the single form of defocus stimulation provided by contact lenses, resulting in a gradual weakening of their myopia prevention and control effects.

[0005] There is currently no publicly available clinical data on the effectiveness of scattering microlens layout designs. Analysis suggests that, on the one hand, these contact lenses, due to the design of even more microscopic microlenses within a relatively small surface, are expensive to manufacture and difficult for the average consumer to accept. On the other hand, the duration of their effectiveness remains unclear.

[0006] Therefore, there is an urgent need for a contact lens that can provide a continuous and effective myopia suppression effect for patients with refractive errors.

[0007] Public content

[0008] In view of the above-mentioned status of contact lenses according to the prior art, one of the objectives of the present disclosure is to provide a contact lens that can permanently suppress the progression of refractive error of the eye.

[0009] This object is achieved by disclosing the following contact lens. The contact lens is easy to rotate when worn, and is characterized in that the contact lens comprises:

[0010] The contact lens comprises:

[0011] a vision correction zone having a first optical power based on an eye prescription and comprising a first correction zone located in a central region of the contact lens; and

[0012] a vision control zone, the vision control zone surrounding the first correction zone and being annular, the equivalent refractive power of the vision control zone being positive compared to the first refractive power, the vision control zone comprising a first control zone adjacent to the first correction zone, the boundary line between the first control zone and the first correction zone being a first inner edge defined by a first inner circle and a first outer circle and undulating reciprocatingly in the circumferential direction of the contact lens, and the diameter d1 of the first inner circle satisfies:

[0013] 2.4mm≤d1≤3.6mm,

[0014] The diameter d2 of the first outer circle satisfies:

[0015] d1+0.2mm≤d2.

[0016] The human eye has the best visual acuity at the fovea center, and the vision worsens as it moves toward the periphery. For a human eye with a macular area diameter of 2.75mm, the boundary of the contact lens vision correction area corresponding to the macular area is approximately 2.8mm. Taking into account the differences in the anatomical structures of the eyeballs of different patients, the first correction area disclosed in the present invention is set between 2.4mm and 3.6mm, thereby ensuring good correction of the refractive error in the central visual area and ensuring the user's clear vision. On this basis, the inner boundary of the first correction area is set in a fluctuating form, and the first outer circle diameter is set to be at least 0.2mm larger than the first inner circle diameter, which can maximize the defocus index of the first correction area and enhance the myopia control effect. Specifically, the user's blinking will cause the contact lens to rotate slightly, and the fluctuating boundary causes the defocus stimulus exposed to the corresponding visual area of ​​the eye (retina) to change compared to before, thereby achieving a changing defocus stimulation effect. Because the human eye blinks constantly, contact lenses rotate at a relatively high frequency. This causes the wearer's visual area to experience constant defocus stimulation, creating a dynamic stimulation effect. This design allows the contact lenses to maintain their myopia prevention and control effects for a longer period of time.

[0017] In addition to the dynamic stimulation effect caused by the rotation of the contact lens due to blinking of the human eye during the wearing process, since the position of the contact lens on the eyeball (specifically the circumferential position) is not fixed each time it is worn, combined with the circumferential non-uniformity of the design of the contact lens defocus stimulation area, the stimulation effect obtained by the wearer each time he wears it is also different.

[0018] Preferably, in a frontal view of the contact lens, within any central angle of the contact lens not exceeding 30°, the first inner edge has at least two different radial dimensions. Research has shown that for contact lenses without anti-rotation features, the angle of rotation caused by blinking is generally within ±20°. Based on this, the first inner edge designed above ensures that the radial dimension of the first inner edge varies within the range of contact lens rotation caused by blinking, ensuring dynamic defocus stimulation with each blink.

[0019] Preferably, in the front view direction of the contact lens, at least part of the first inner edge consists of an arc segment located on the first inner circle and an arc segment located on the first outer circle; and / or

[0020] At least a portion of the first inner edge is composed of a first curve with a middle portion concave toward the center of the contact lens or convex away from the center of the contact lens.

[0021] Preferably, the diameter of the first outer circle satisfies: d2≤3.6mm, and d1+0.4mm≤d2≤d1+1.2mm, thereby achieving a good balance between the wearer's need for clear vision and the goal of obtaining a larger defocus control area.

[0022] Preferably, the first curve is selected from any one of a circular arc, a spline curve, a Bezier curve, and a high-order polynomial curve.

[0023] Preferably, the first control zone includes a first outer edge, and the outer diameter d3 of the first outer edge satisfies the following: d2 + 0.8 mm ≤ d3 ≤ d2 + 1.4 mm. Furthermore, preferably, the first outer edge satisfies the following: 3.8 mm ≤ d3 ≤ 5.2 mm. While providing clear vision, the first control zone of this size achieves a larger defocus control area, ensuring more significant defocus stimulation and improving myopia control.

[0024] Preferably, the first outer edge of the first control zone is circular, and the centers of the first inner circle and the first outer circle coincide with each other.

[0025] Preferably, the first correction zone covers a visual range of no less than 10° from the fovea of ​​the eyeball. Preferably, the first inner circle corresponds to a 10° visual angle from the fovea. The first control zone should be outside the first correction zone and within the corresponding pupil area. Therefore, the first control zone is primarily set within the core sensitive period of foveal defocus control, 10°-20° from the fovea.

[0026] Preferably, the vision correction zone includes a second correction zone surrounding the first control zone, and the vision control zone includes a second control zone surrounding the second correction zone.

[0027] Preferably, the boundary line between the second control zone and the second correction zone is defined by a third inner circle and a third outer circle and is a second inner edge that undulates reciprocally in the circumferential direction of the contact lens, wherein the diameter d4 of the third inner circle satisfies: 0.2mm+d3≤d4.

[0028] Preferably, the second control area includes a non-circular second inner edge, and the diameter d4 of the inner circle of the second inner edge satisfies: 0.4mm+d3≤d4≤d3+2mm; more preferably, satisfies: 0.5mm+d3≤d4≤d3+1.2mm.

[0029] Preferably, the diameter d4 satisfies: 4.2 mm ≤ d4 ≤ 5.6 mm; more preferably, satisfies: 4.4 mm ≤ d4 ≤ 5.2 mm.

[0030] Preferably, within any central angle region not greater than 30°, the second inner edge has at least two different radial dimensions.

[0031] Preferably, in at least a portion of the central angle region of the contact lens, the second inner edge and the first inner edge are parallel to each other, and their circumferential fluctuation trends are synchronized.

[0032] Preferably, the diameter d5 of the outer circle of the second inner edge satisfies:

[0033] d4+0.6mm≤d5≤d4+1.2mm.

[0034] Preferably, the second control zone includes a second outer edge, and a diameter d6 of an outer circle of the second outer edge satisfies:

[0035] d5+0.6mm≤d6≤d5+2.6mm;

[0036] Preferably, the diameter d6 satisfies:

[0037] d5+0.8mm≤d6≤d5+1.5mm.

[0038] Preferably, the diameter d6 of the outer circle of the second outer edge satisfies:

[0039] 7mm≤d6≤8.2mm;

[0040] Preferably, the diameter d6 satisfies:

[0041] 7.2mm≤d6≤8mm.

[0042] Preferably, the second control zone is located within a visual range of 15°-25° of the fovea of ​​the eyeball, and preferably, is located within a visual range of 18°-23° of the fovea of ​​the eyeball.

[0043] Preferably, the equivalent refractive power of the second control zone is not less than the equivalent refractive power of the first control zone.

[0044] Preferably, the refractive power of the second control zone increases gradually from the inside to the outside of the contact lens in the radial direction. The progressive diopter design of the second control zone results in a gentler change in refractive power along the circumference than the abrupt change design of the first control zone. While maintaining a dynamic stimulation effect, this reduces the discomfort experienced by some people with sensitive vision, making initial adaptation to the lens easier.

[0045] Preferably, the vision control zone further includes a third control zone surrounding and adjacent to the second control zone. The third control zone has a width selected from 0.8 mm to 1.5 mm and has uniform refractive power. The uniform refractive power of the third control zone ensures a defocused area and amount at the periphery of the retina, contributing to the effectiveness of myopia control. Preferably, the inner and outer edges of the third control zone are circular.

[0046] Preferably, the outer diameter of the third control zone is greater than 8 mm and less than 9 mm.

[0047] On the basis of conforming to the common sense in this field, the above-mentioned preferred implementation modes can be arbitrarily combined to obtain the preferred embodiments of the present disclosure.

[0048] The contact lenses designed in this disclosure provide continuous dynamic defocus stimulation to the eye, weakening the eye's automatic compensation for defocus stimulation. The user's normal physiological blinking, as well as the act of removing and putting on the contact lenses, causes the contact lenses to spontaneously rotate, providing differentiated defocus stimulation to the user's eyes. As a result, the contact lenses can provide long-term, effective myopia prevention and control. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] To better understand the above and other objects, features, advantages, and functions of the present disclosure, reference may be made to the preferred embodiments shown in the accompanying drawings. Like reference numerals in the accompanying drawings refer to like components. Those skilled in the art should understand that the accompanying drawings are intended to schematically illustrate preferred embodiments of the present disclosure and have no limiting effect on the scope of the present disclosure. The components in the drawings are not drawn to scale.

[0050] Figure 1 is a schematic structural diagram of the front side of a contact lens according to a first preferred embodiment of the present disclosure;

[0051] Figure 2 is based on Figure 1 A partial schematic diagram of a contact lens;

[0052] Figure 3 is a schematic structural diagram of the front side of a contact lens according to a second preferred embodiment of the present disclosure;

[0053] Figure 4 is based on Figure 2 A partial schematic diagram of a contact lens;

[0054] Figure 5 This is a map of the distribution of cones and rods on the retina.

[0055] FIG6 is a schematic diagram showing the location of the area on the contact lens where optical simulation is performed.

[0056] FIG7 is a schematic diagram of the MTF of each region in FIG6 . DETAILED DESCRIPTION

[0057] Next, the disclosed concept of the present disclosure will be described in detail with reference to the accompanying drawings. What is described here is only a preferred embodiment according to the present disclosure. Those skilled in the art can think of other ways to implement the present disclosure on the basis of the preferred embodiment, and the other ways also fall within the scope of the present disclosure. In the following specific description, directional terms such as "upper", "lower", "inner", "outer", "longitudinal", "horizontal" and the like are used with reference to the directions described in the accompanying drawings. The components of the embodiments of the present disclosure can be placed in a variety of different directions, and the directional terms are for illustrative purposes only and are not restrictive.

[0058] In the present disclosure, the term "contact lens" refers generally to an ophthalmic lens suitable for fitting on the front surface of the human eye. It should be understood that the contact lens provides clinically acceptable supraorbital movement without being embedded in the eyeball and causing damage to the eyeball. Contact lenses are also called contact lenses, which can be corneal contact lenses, scleral contact lenses, corneoscleral contact lenses, etc. Corneal contact lenses usually land on the human cornea or corneal limbus; scleral contact lenses usually land on the sclera; corneoscleral contact lenses usually land on the corneal limbus or on the corneal limbus and sclera. The contact lens can be a soft contact lens, such as a hydrogel contact lens or a silicone hydrogel contact lens; it can be a hard contact lens, such as a lens made of hard materials such as polymethyl methacrylate (PMMA) and silicone methacrylate (SiMA); it can also be a lens made of soft materials and hard materials together.

[0059] A front view of a contact lens, which corresponds to a view directly in front of the center of the contact lens. The front of the contact lens is the surface facing away from the eye (called the "outer surface" or "anterior surface"); the back of the contact lens is the surface that comes into contact with the eye (called the "inner surface" or "posterior surface").

[0060] According to the present disclosure, contact lenses can be generally divided into an optical zone 1 that has optical functions and directly affects the vision of the human eye, and non-optical zones 13, 13' that do not directly affect the vision of the human eye. The optical zone 1 includes areas such as the vision correction zone 10, 10' and the vision control zone 20, 20'; the non-optical zone 13, 13' includes a landing zone for ensuring the firmness of the contact lens wearing and the quality of tear exchange in the inner and outer areas of the contact lens, as well as an edge warp to ensure the quality of tear exchange in the inner and outer areas of the contact lens and wearing comfort. Depending on the specific type of contact lens, the landing zone corresponds to different areas of the user's eye. For example, for scleral contact lenses, the landing zone corresponds to the sclera of the eye. As for the landing zone and the edge warp, they are not the focus of this article and will not be elaborated on below. The following will only elaborate on the vision correction zone and the vision control zone in the design points of this article.

[0061] The contact lens involved in the present disclosure is a contact lens that is easy to rotate when worn. As is well known, technologies to ensure that the contact lens does not rotate as much as possible include prism ballast, double slab-off, and truncation. Such technologies basically involve specific designs on the edge of the contact lens 100. Generally speaking, contact lenses 100 without specific designs on the edge can rotate slightly due to the pressure of the eyelids when the wearer blinks. Studies have shown that when a person blinks, a conventionally designed contact lens 100 can rotate around the eye axis with the help of the pressure of the eyelids and the natural rotation of the eyeball. Since conventionally designed contact lenses can maintain rotation, the design of how the contact lens can achieve rotation around the eye axis is well known and will not be described in detail below.

[0062] In the following, for the common parts of each example, such as the data used to constrain the boundary line size, please refer to Figure 1 、 2 and its related expressions to understand, Figure 1 、 2 Examples other than those mentioned above will not be repeated for the common parts.

[0063] The following describes the relevant concepts of the present disclosure with reference to the specific drawings.

[0064] Combine Figure 1 As described above, the contact lens 100 according to the present disclosure includes an optical zone 1 and a non-optical zone 13, wherein the optical zone 1 is composed of a vision correction zone 10 and a vision control zone 20. The vision correction zone 10 in the optical zone 1 has a first refractive power based on the prescription of the eyeball, and includes a first correction zone 11 located in the central area of ​​the contact lens 100, and a second correction zone 12 located radially outward of the first correction zone. The vision correction zone 10 is intended to correct any one or more vision defects of the eye, such as myopia, hyperopia, astigmatism, etc. In addition, the vision correction zone 10 can also have 0 diopter. In the case where the vision correction zone 10 is 0 diopter, the contact lens 100 of the present disclosure is used to suppress the risk of the relevant wearer developing myopia in the future. Generally speaking, based on the contact lens 100 of the present disclosure, young children and children with insufficient hyperopia reserve can be fitted with a contact lens 100 with a 0 diopter vision correction zone 10.

[0065] The vision control zone 20 surrounds the first correction zone 11 and is annular in shape. It should be noted that the term "annular" herein does not refer solely to a circular ring; it also encompasses other annular shapes. Furthermore, localized microscopic interruptions in the annular vision control zone also fall within the "annular vision control zone" sought to be protected by this disclosure. Furthermore, as described below, a vision control zone 20 comprised of multiple annular sub-areas also falls within the "annular vision control zone" sought to be protected by this disclosure.

[0066] The equivalent refractive power of the vision control area 20 is a positive refractive power compared to the first refractive power, that is, the equivalent refractive power of the vision control area 20 has a positive additional refractive power. E , which can be expressed as follows:

[0067]

[0068] Among them, D i represents the diopter of a sub-area with a single diopter, A i Represents the area under the emmetropia direction of a sub-area with a single diopter.

[0069] For myopic patients, the first refractive power is negative. Depending on the absolute value of the negative first refractive power, the equivalent refractive power of the vision control area 20 can be positive or negative. Generally speaking, when the absolute value of the first refractive power is small, the equivalent refractive power of the vision control area 20 is positive or 0°. When the absolute value of the first refractive power is large, the equivalent refractive power of the vision control area 20 is negative.

[0070] See also Figure 1 In the example shown, in the front view direction, the vision control area 20 includes a first control area 21, a second control area 22, and a third control area 23 arranged in sequence in the radial direction of the contact lens 100. Figure 1 As described above, in this example, the contact lens 100 is radially arranged in sequence from the inside to the outside of the first correction zone 11 , the first control zone 21 , the second correction zone 12 , the second control zone 22 , and the third control zone 23 .

[0071] Combine Figure 2 ,in Figure 2 Shown Figure 1 The first correction area 11 and the first control area 21. The boundary line between the first control area 21 and the first correction area 11 is the first inner edge S11. Figure 2 As shown in the partially enlarged view of the contact lens 100 , the first inner edge S11 is defined by a first inner circle C11 and a first outer circle C12 and is a sawtooth curve that undulates back and forth in the circumferential direction of the contact lens 100 .

[0072] It should be noted that although the term "radial" is used in the above description herein, this "radial" refers only to the perpendicular direction relative to the circumferential direction, representing the direction extending from the center to the outer edge of the contact lens 100, and does not necessarily imply that "the contact lens 100 has a circular surface shape." The contact lens 100 disclosed herein may have other non-circular surface shapes, such as an elliptical or saddle-shaped shape. Unless otherwise specified, the "surface shape" in this disclosure refers to the shape defined by the outer edge of the contact lens 100 as a whole or a local area of ​​the contact lens 100, as viewed along the normal direction of the local center of the contact lens 100. For example, the example of the contact lens 100 having a circular surface shape in the above description means that after the contact lens 100 is worn, the contact lens 100, as viewed from the front of the wearer by a third person, appears generally circular.

[0073] The term "the boundary line fluctuates back and forth in the circumference of the contact lens 100" means that at different positions on the circumference of the contact lens 100, the boundary line has different distances from the center of the contact lens 100, and the distances are distributed in a fluctuating manner. As long as the condition of "being defined by the first inner circle and the first outer circle and fluctuating back and forth in the circumference of the contact lens" is met, the first inner edge S11 can be in any form. For example, Figure 1 In the example shown, the first inner edge S21 is formed by alternating arc segments located on the first inner circle C21 and arc segments located on the first outer circle C22. Figure 3 In another example shown, the first inner edge S21 is a concave curve with multiple segments whose middle portions are concave toward the center of the contact lens 100 (see the relevant description of "first curve" below). The concave curve can also be replaced by a convex curve with multiple segments whose middle portions are convex away from the center of the contact lens 100. In other examples not shown, for example, the first inner edge can also be in the form of a plurality of interconnected straight lines or non-straight lines, wherein the non-straight line can be an arc or a form of a straight line segment and an arc segment connected. The non-straight line can also be a circular arc, a spline curve, a Bezier curve, or a high-order polynomial curve. The constituent line segments of the first inner edge can be composed of a variety of different line segments, specifically, can be composed of any combination of interconnected circular arc curves, concave curves, convex curves, straight lines, or any non-straight lines as described above.

[0074] The non-circular configuration of the first inner edge S11 ensures that, after the contact lens 100 is rotated, the refractive powers of at least some of the cones (or rods) in the optical zone of the contact lens 100 corresponding to each of the contact lens 100's cones (or rods) vary, thereby producing different defocus stimuli for the eye. Furthermore, the undulating design of the control zone boundary provides a longer boundary, thereby producing a favorable boundary stimulation effect (see the simulated effects of the boundary between the first control zone 21 and the first correction zone 11 described below in conjunction with Figures 6-7).

[0075] Combine Figure 1 、 2 ,in Figure 2 Shown Figure 1 In the example of the first correction zone 11 and the first control zone 21, the diameter d1 of the first inner circle C11 for limiting the first inner edge S11 is set to any value in the range of 2.4 mm to 3.6 mm; the diameter d2 of the first outer circle C12 is set to be at least 0.2 mm larger than the diameter of the above-mentioned first inner circle C11.

[0076] Under the premise that the diameter d1 of the first inner circle C11 is set within the range of 2.4mm-3.6mm, the diameter of the first inner circle C11 projected onto the retina by the diameter d1 is equal to or slightly larger than the diameter of the macular area. Taking a wearer with an axial length of 24mm and a macular radius of 2.8mm as an example, according to the simplified optical model of the eye, the diameter projected on the central area of ​​the contact lens is 2.8mm. According to the present disclosure, the diameter d1 of the first inner circle C11 can be set to a size slightly larger than the diameter of the macular area, such as 2.9mm or 3mm, to ensure that when the contact lens sags due to gravity, the first inner circle can cover the visual area corresponding to the macular area to ensure vision. In general, according to the present disclosure, the diameter of the first inner circle C11 is basically 0-0.2mm larger than the diameter of the projection area of ​​the macular area on the contact lens.

[0077] Previous studies have shown that when a wearer wears a contact lens 100 without a specific edge design, the eyelid's squeezing action on the contact lens 100 during blinking causes it to rotate, with the angle of rotation around the eye axis within ±20°. To address this, previous studies have mostly focused on reducing contact lens 100 rotation, and have proposed designs such as prism ballast, double slab-off, and truncation, as described above. Related designs can be found in the disclosures of CN109937376A and US20210208423A1.

[0078] To address this issue, the present disclosure proposes a different concept. Specifically, the contact lens 100 of the present disclosure retains its original characteristic of being easily rotated within an angle of ±20° by blinking, but is designed as follows: within any central angle region of the contact lens 100 not exceeding 30°, the first inner edge S11 of the contact lens 100 has at least two different radial dimensions. In other words, the radial dimension of the first inner edge S11 changes at least once within any central angle region corresponding to not exceeding 30°.

[0079] exist Figure 1In the example, the diameter of the first inner edge S11 changes two or three times within a 30° central angle region. It can be understood that when the 30° central angle region corresponds to a continuous arc segment of the first inner edge S11, the first edge changes a total of three times at both ends of the arc segment or the first curve and along the main portion of the arc segment or the first curve.

[0080] See also Figure 3 、 4 According to the second preferred embodiment of the present disclosure, the size ranges of the first inner circle and the first outer circle C21 and C22 related to the first inner edge S21 are the same as 1 and 2, and are not repeated here.

[0081] exist Figure 3 、 4 In the example, with Figure 1 、 2 The difference from the example is that the diameter of the first inner edge S21 changes continuously (ie, changes countless times) within the central angle region of 30°.

[0082] Figure 1-4 The diameter d2 of the first outer circle C12, C22 of the first inner edge S11, S21 of the first control zone 21, 21' is set to be no greater than 3.6 mm. At the same time, the diameter d2 is set to satisfy the following conditions: d1+0.4 mm≤d2≤d1+1.2 mm. After blinking or other means, the maximum unit defocus area variation caused by the rotation of the contact lens 100, 100' is within 1.8 mm. 2 / rad-0.88mm 2 / rad.

[0083] The first inner circles C11 , C21 and the first outer circles C12 , C22 defining the first inner edges S11 , S21 may be concentrically designed. In this case, the wearer does not need to center the contact lens 100 , 100 ′ when wearing it.

[0084] To ensure visual quality, the first correction zone should be set to cover a visual range of no less than 10° of the fovea of ​​the eyeball. Preferably, the first inner circle corresponds to a 10° visual angle of the fovea.

[0085] For the first outer edges S12 and S22 defining the outer boundaries of the first control zones 21 and 21', the outer boundaries are defined by a second outer circle, wherein the diameter d3 of the outer circle is set to satisfy: d2+0.8mm≤d3≤d2+1.4mm, wherein d3 is the diameter of the second outer circle. Preferably, the first outer edges S12 and S22 satisfy: 3.8mm≤d3≤5.2mm. The first outer edges S12 and S22 preferably adopt Figure 1-4The circular form shown. Under the premise of providing clear vision, the first control area 21 of the above size obtains a larger defocus control area, which can ensure more significant defocus stimulation and improve myopia control. The diameter d3 of the second outer circle can be set to correspond to the wearer's 15° vision of the fovea. Figure 5 , rod cells are most abundant at a position of 15° from the wearer's fovea. Under the premise of providing clear vision, the first control area of ​​the above size obtains a larger defocus control area, which can ensure more significant defocus stimulation and improve myopia control. Figure 5 As can be seen from the distribution of retinal cones and rods, since rods are relatively sensitive to the intensity of light, when the outer boundary of the first control area 21 is set at the above position, the contact lens 100 can ensure that the first control area 21 can provide effective defocus control for the wearer in both light and dark environments, thereby achieving myopia control.

[0086] The second correction zones 12 , 12 ′ and the first correction zones 11 , 11 ′ located outside the first control zones 21 , 21 ′ may optionally adopt the same refractive power.

[0087] Second control zones 22, 22', located outside second correction zones 12, 12', are used to further increase the lens's defocus range. The boundary between second control zones 22, 22' and second correction zones 12, 12' (second inner edges S13, S23) is defined by a third inner circle and a third outer circle and oscillates around the circumference of contact lens 100. The oscillating shape of second inner edges S13, S23 can be described in detail with reference to the description of first inner edge S11. They can also be composed of arc segments, straight line segments, or other arcs, and are not further elaborated here.

[0088] The spacing between the second inner edges S13 and S23 of the second control zones 22 and 22' and the first outer edges S12 and S22 of the first control zones 21 and 21' is no less than 0.2 mm to ensure that the second correction zone 12 between the first and second control zones 21 and 22 can form a complete image. Therefore, the diameter d4 of the third inner circle of the second inner edges S13 and S23 should satisfy 0.2 mm + d3 ≤ d4. Preferably, the following should be satisfied: 0.4 mm + d3 ≤ d4 ≤ d3 + 2 mm; more preferably, the following should be satisfied: 0.5 mm + d3 ≤ d4 ≤ d3 + 1.2 mm.

[0089] Based on this, the specific diameter d4 of the third inner circle defining the second inner edge can be set based on the wearer's pupil diameter under normal lighting conditions. Specifically, the diameter of the third inner circle is preferably set to be 0.2mm-0.4mm smaller than the corresponding wearer's test pupil diameter (under normal white light conditions). The contact lens thus designed can achieve two dynamic defocus stimuli within the wearer's pupil area (one caused by the boundary between the first control zone and the first correction zone, and the other caused by the boundary between the second control zone and the second correction zone).

[0090] Studies on primates have found that primates are relatively sensitive to defocus stimulation within 20° of the center of the macula, and the myopia control effect brought about by the defocus design is relatively obvious. For this reason, in the contact lenses 100, 100' of the present disclosure, the second inner edges S13, S23 are at least partially located within the 20° visual angle range of the wearer's macula center. For example, specifically, the second inner edges S13, S23 preferably fluctuate back and forth with the visual boundary line (the visual boundary line can be understood as a circle) corresponding to any angle within the range of 18°-22° of the wearer's fovea as the center line. More preferably, it fluctuates back and forth with the 20° visual angle boundary line of the wearer's fovea as the center line. Based on this, the diameter d4 of the inner circle of the second inner edges S13, S23 should satisfy:

[0091] 4.2mm≤d4≤5.6mm;

[0092] Preferably, the following conditions are met:

[0093] 4.4mm≤d4≤5.2mm.

[0094] It should be understood that d4 values ​​within the range of 4.2 mm to 5.6 mm do not conflict with d4 values ​​within the range of 4 mm + d3 to d3 + 2 mm. When d4 satisfies both conditions, it ensures that the second correction zones 12 and 12' form a clear image, while the boundaries of the second control zones 22 and 22' fall within the defocus stimulus sensitive zone.

[0095] Continue to combine Figure 1-4 To illustrate, in the illustrated example, the first inner edges S11 and S21 of the first control zones 21 and 21' and the second inner edges S13 and S23 of the second control zones 22 and 22' are each segmented parallel to each other, and their circumferential fluctuation trends are the same. At this point, at each radial position, the spacing between the corresponding circumferential positions of the first inner edges S11 and S21 and the second inner edges S13 and S23 is constant. It should be understood that the first inner edges S11 and S21 of the first control zones 21 and 21' and the second inner edges S13 and S23 of the second control zones 22 can also be designed so that some segments are parallel to each other and their circumferential fluctuation trends are the same.

[0096] To provide more retinal boundary stimulation, the diameter d5 of the third outer circle defining the outer periphery of the second inner edges S13 and S23 is preferably set to satisfy the following: d4 + 0.6 mm ≤ d5 ≤ d4 + 1.2 mm. For pupil diameters of 2.5-3.1 mm, the diameter d5 of the third outer circle of the contact lens is set between 5 and 6.2 mm. In normal bright conditions, the user's pupil is approximately 3 mm. This third outer circle fits within the pupil area, ensuring two annular defocus zones within the pupil area. As the lens moves within the eye, the retina receives more boundary stimulation, reducing the appearance of adaptation and enhancing the myopic effect.

[0097] Preferably, the second control areas 22, 22' include second outer edges S14, S24, and the outer circle diameter d6 of the second outer edges S14, S24 satisfies: d5+0.6mm≤d6≤d5+2.6mm; more preferably, the diameter d6 satisfies: d5+0.8mm≤d6≤d5+1.5mm.

[0098] Preferably, the diameter d6 of the outer circle of the second outer edges S14 and S24 satisfies:

[0099] 7mm≤d6≤8.2mm;

[0100] Preferably, the diameter d6 satisfies:

[0101] 7.2mm≤d6≤8mm.

[0102] The second control zones 22, 22' are preferably set within a visual range of 15°-25° from the fovea of ​​the eyeball, more preferably within a visual range of 18°-23° from the fovea of ​​the eyeball, so as to ensure that the second control zone 22 is substantially located within the defocus stimulus sensitivity area of ​​the wearer's fovea.

[0103] The equivalent refractive power of the second control zone 22, 22' can be set to be greater than the equivalent refractive power of the first control zone 21, 21'. In one example, in the radial direction of the contact lens 100, 100', the refractive power of the second control zone 22, 22' gradually increases from the inside to the outside. The starting refractive power of the second control zone 22, 22' can be the first refractive power of the vision correction zone 10, 10', or a refractive power slightly greater than the first refractive power. The second control zone adopts a progressive light addition design so that the change in refractive power on the circumference is gentler than the sudden change design of the first control zone. On the basis of ensuring the dynamic stimulation effect, it reduces the degree of discomfort of some people with sensitive vision, making it easier to adapt to the lens in the early stage of wearing.

[0104] In another example, the refractive power of the second control zones 22, 22' is non-gradually designed. Specifically, the second control zones 22, 22' may have a single refractive power or a limited number of multiple refractive powers. If the second control zones 22, 22' have multiple refractive powers, different refractive powers may be used in different circumferential and / or radial regions of the second control zones 22, 22'.

[0105] The vision control zone 20 also includes third control zones 23 and 23' surrounding and adjacent to the second control zone 22. The third control zones 23 and 23' have a width selected from 0.8 mm to 1.5 mm and have uniform refractive power. The uniform refractive power of the third control zones ensures a defocused area and amount at the periphery of the retina, thereby contributing to myopia control.

[0106] The inner and outer edges of the third control areas 23 and 23' can be circular in design. The outer diameter of the third control area 23 can be set to be greater than 8 mm and less than 9 mm.

[0107] See also Figure 3 、 4 In the second preferred embodiment, the boundary lines of each control area and correction zone (the first inner edge S11, the second inner edge S13, S23) are continuous smooth curves. Figure 1 Compared with the first embodiment shown, the boundary lines (first inner edge S21, second inner edge S23) of this form are in the front view direction of the contact lens 100. The rotation process of the contact lens 100' brings relatively little difference in the wearer's vision, and the patient can adapt more easily in the initial wear.

[0108] Figure 3 、 4 The number of first curves, each with a center portion concave toward the center of the contact lens 100', is selected to be 6. In fact, the number of first curves can be any number not less than 3, preferably selected from 5 to 8. Since the angle of rotation of the contact lens caused by blinking is generally within ±20°, the first inner edge S11 of the polygonal first control zone 21 composed of 5 to 8 first curves ensures that within the range of rotation of the contact lens 100 caused by blinking, the edge of the first correction zone 11 (first control zone 21) has the largest refractive power variation region, ensuring the largest dynamic defocus stimulation area.

[0109] In this embodiment, the contact lens 100 has a substantially circular face shape. Alternatively, the contact lens 100 may have a rectangular, square or other irregular shapes.

[0110] The following describes the optical effect of the contact lens according to the present disclosure in conjunction with simulation data. Referring to the MTF (Modulation Transfer Function) diagrams in Figures 6-7, the MTF simulation setting conditions are as follows: assuming the object point is infinitely far away, the spatial ray tracing method is used to calculate the lens refraction wave surface at each position, and then combined with fast Fourier transform to obtain the MTF of each corresponding area. The overall contact lens optical design adopts Figure 1 For example, the diameter of the first inner circle is 3mm, the diameter of the first outer circle is 3.4mm, and the diameter of the second outer circle is 4.8mm. Figures 6A-6C The MTF shown is taken from an elliptical area with a major axis of 0.3 mm and a minor axis of 0.1 mm at the location on the contact lens. Figure 6A In the figure, the entire ellipse is located in the raised sector area of ​​the first control area, and its minor axis forms an angle of 15° with the vertical. For the sake of convenience, this area is referred to as area A. Figure 6B In the figure, the minor axis of the ellipse is located in the radial direction of the vertical position of the contact lens, the left half of the ellipse is located in the first control zone, and the right half is located in the first correction zone. For the convenience of description, this zone is referred to as zone B. Figure 6C In the figure, the entire ellipse is located in the convex sector of the first correction zone, with its minor axis forming a 15° angle with the vertical. For ease of description, this area is referred to as area C. The position of the ellipse in the contact lens can be seen Figures 6A-6C Schematic diagram of .

[0111] Depend on Figures 7A-7C As can be seen from the diagram, in general, the MTF values ​​of regions A to C decrease in sequence, and as the spatial frequency increases, the difference in MTF values ​​between regions A and C becomes increasingly larger. Region A's MTF value decreases below 0.2 in the high-frequency range (above 13.5 lp / mm (line pairs / mm)), resulting in blurred imaging in the corresponding retinal area, which corresponds to the original intention of adopting a defocus design in this area. Figure 7B and Figure 7A 、 Figure 7C It can be seen that at the edge position corresponding to the first correction area and the first control area, Figure 7B The MTF values ​​in the corresponding region B exhibit significant fluctuations, indicating that the image quality in this retinal region is actually poor. Combined with the reciprocating fluctuations of the boundary between the first correction zone and the first control zone, the image quality in this boundary region exhibits significant differences across spatial viewing angles, creating a dynamic visual stimulation effect under dynamic viewing. Therefore, effectively increasing the length of boundary line S11 will help enhance this dynamic stimulation effect.

[0112] The scope of protection of the present disclosure is limited only by the claims. Thanks to the teachings of this disclosure, those skilled in the art will readily recognize that alternative structures to the structures disclosed in this disclosure can be used as feasible alternative embodiments, and that the embodiments disclosed in this disclosure can be combined to produce new embodiments, which also fall within the scope of the appended claims.

[0113] Description of the accompanying drawings:

[0114] Contact lenses: 100, 100'.

[0115] Vision correction zone: 10, 10'.

[0116] First correction area: 11, 11'.

[0117] Second correction zone 12: 12, 12'.

[0118] Vision control area: 20, 20'.

[0119] First control area: 21, 21'.

[0120] Second control zone: 22, 22'.

[0121] Third control zone: 23, 23'.

[0122] First inner edge: S11, S21.

[0123] First inner circle: C11, C21.

[0124] First outer circle: C12, C22.

[0125] First outer edge: S12, S22.

[0126] Second inner edge: S13, S23.

[0127] Second outer edge: S14, S24.

[0128] The outer edge of the third control zone: S15, S25.

Claims

1. A contact lens that is easily rotated when worn, characterized in that: The contact lens comprises: a vision correction zone having a first optical power based on an eye prescription and comprising a first correction zone located in a central region of the contact lens; and a vision control zone, the vision control zone surrounding the first correction zone and being annular, the equivalent refractive power of the vision control zone being positive compared to the first refractive power, the vision control zone comprising a first control zone adjacent to the first correction zone, the boundary line between the first control zone and the first correction zone being a first inner edge defined by a first inner circle and a first outer circle and undulating reciprocatingly in the circumferential direction of the contact lens, and the diameter d1 of the first inner circle satisfies: 2.4mm≤d1≤3.6mm, The diameter d2 of the first outer circle satisfies: d2≤3.6mm, and d1+0.2mm≤d2≤d1+1.2mm; and In a front view direction of the contact lens, the first inner edge has at least two different radial dimensions within any central angle region of the contact lens that is no greater than 30°.

2. The contact lens according to claim 1, wherein: In the front view direction of the contact lens, at least a partial section of the first inner edge consists of an arc segment located on the first inner circle and an arc segment located on the first outer circle; and / or At least a portion of the first inner edge is composed of a first curve with a middle portion concave toward the center of the contact lens or convex away from the center of the contact lens.

3. The contact lens according to claim 2, wherein: The first curve is selected from any one of a circular arc, a spline curve, a Bezier curve, and a high-order polynomial curve.

4. The contact lens according to any one of claims 1 to 3, characterized in that: The first control area includes a first outer edge, and the outer boundary of the first outer edge is defined by a second outer circle, and the diameter d3 of the second outer circle satisfies: d2+0.8mm≤d3≤d2+1.4mm.

5. The contact lens according to claim 4, wherein: The first outer edge satisfies: 3.8 mm ≤ d3 ≤ 5.2 mm.

6. The contact lens according to claim 4, wherein: The first outer edge of the first control area is circular.

7. The contact lens according to claim 6, wherein: The centers of the first inner circle and the first outer circle coincide with each other.

8. The contact lens according to claim 1, wherein: The first correction zone covers a visual range of no less than 10° of the fovea of ​​the eyeball.

9. The contact lens according to claim 8, wherein: The first inner circle corresponds to a 10° visual angle of the fovea.

10. The contact lens according to claim 4, wherein: The vision correction zone includes a second correction zone surrounding the first control zone, and the vision control zone includes a second control zone surrounding the second correction zone.

11. The contact lens according to claim 10, wherein: The boundary line between the second control zone and the second correction zone is a second inner edge defined by a third inner circle and a third outer circle and undulating reciprocally in the circumferential direction of the contact lens, wherein the diameter d4 of the third inner circle satisfies: 0.2mm+d3≤d4.

12. The contact lens according to claim 11, wherein: The diameter d4 of the third inner circle satisfies: 0.4 mm + d3 ≤ d4 ≤ d3 + 2 mm.

13. The contact lens according to claim 11, wherein: The diameter d4 of the third inner circle satisfies: 0.5mm+d3≤d4≤d3+1.2mm.

14. The contact lens according to claim 13, wherein: The diameter d4 satisfies: 4.2 mm ≤ d4 ≤ 5.6 mm.

15. The contact lens according to claim 13, wherein: The diameter d4 satisfies: 4.4 mm ≤ d4 ≤ 5.2 mm.

16. The contact lens according to claim 14, wherein: In any central angle region not greater than 30°, the second inner edge has at least two different radial dimensions.

17. The contact lens according to claim 16, wherein: In at least a portion of the central angle region of the contact lens, the second inner edge and the first inner edge are parallel to each other, and their circumferential fluctuation trends are synchronized.

18. The contact lens according to any one of claims 11 to 16, characterized in that: The diameter d5 of the third outer circle satisfies: d4+0.6mm≤d5≤d4+1.2mm.

19. The contact lens according to claim 18, wherein: The second control zone includes a second outer edge, and the outer boundary of the second outer edge is defined by a fourth outer circle, and the diameter d6 of the fourth outer circle satisfies: d5+0.6mm≤d6≤d5+2.6mm.

20. The contact lens according to claim 19, wherein: The diameter d6 of the fourth outer circle satisfies: d5+0.8mm≤d6≤d5+1.5mm.

21. The contact lens according to claim 19 or 20, characterized in that The diameter d6 of the fourth outer circle satisfies: 7 mm ≤ d6 ≤ 8.2 mm.

22. The contact lens according to claim 19 or 20, characterized in that The diameter d6 of the fourth outer circle satisfies: 7.2 mm ≤ d6 ≤ 8 mm.

23. The contact lens according to claim 10, wherein: The second control area is located in the visual range of 15°-25° of the fovea of ​​the eyeball.

24. The contact lens according to claim 10 or 23, characterized in that: The visual range of 18°-23° is located in the fovea of ​​the eyeball.

25. The contact lens of claim 10, wherein: The equivalent refractive power of the second control zone is not less than the equivalent refractive power of the first control zone.

26. The contact lens according to claim 25, wherein: In the radial direction of the contact lens, the refractive power of the second control zone gradually increases from the inside to the outside.

27. The contact lens of claim 10, wherein: The vision control zone further includes a third control zone surrounding and adjacent to the second control zone, the width of the third control zone is selected from 0.8 mm to 1.5 mm, and the third control zone has uniform refractive power.

28. The contact lens according to claim 27, wherein The inner edge and the outer edge of the third control zone are circular.

29. The contact lens according to claim 28, wherein The outer diameter of the third control zone is greater than 8 mm and less than 9 mm.

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