MULTI-CURVE MULTI-SECTION ALIGNMENT STRUCTURE FOR ORTHOKERATOLOGY LENS AND METHOD THEREOF
20220082862 · 2022-03-17
Inventors
Cpc classification
International classification
Abstract
A multi-curve multi-section alignment structure for an orthokeratology lens and a method thereof are disclosed. The orthokeratology lens includes a base curve formed on a central part of an inner surface thereof, and a reverse curve outwardly formed outside the base curve, an alignment curve outwardly formed outside the reverse curve and configured to align to a cornea of an eyeball, and a peripheral curve outwardly formed outside the alignment curve. The cornea has an alignment region contacting the alignment curve, and the alignment region is divided into sections, and the alignment curve includes alignment sections formed correspondingly in position to the sections and matching curvatures of the sections of the alignment region, so that the orthokeratology lens can be stably aligned with the eyeball, and when a wearer's eyelid is closed, the orthokeratology lens cannot decenter easily.
Claims
1. A multi-curve multi-section alignment structure for an orthokeratology lens, wherein the orthokeratology lens comprises a base curve formed on a central part of an inner surface thereof and configured to apply a positive pressure on a surface of a cornea of an eyeball by tears sandwiched between the lens and the cornea, a reverse curve outwardly formed outside the base curve, an alignment curve outwardly formed outside the reverse curve and configured to align on the cornea, and a peripheral curve outwardly formed outside the alignment curve, wherein the cornea comprises an alignment region in contact with the alignment curve, and the alignment region is divided into a plurality of sections, and the alignment curve comprises a plurality of alignment sections formed correspondingly in position to the plurality of sections and matching curvatures of the plurality of sections of the alignment region.
2. The multi-curve multi-section alignment structure according to claim 1, wherein the amount of the plurality of alignment sections of the alignment curve is even number.
3. The multi-curve multi-section alignment structure according to claim 1, wherein the inner surface of the lens is aspheric.
4. A method of producing an orthokeratology lens with a multi-curve multi-section alignment structure, comprising: (A): using a corneal topography to measure a cornea of an eyeball, to obtain a plurality of keratometry measurement of the cornea; (B): using an electronic device to perform calculation of curvature for the cornea of the eyeball, dividing an alignment region, which matches with the alignment curve of the lens to be produced, of the cornea into a plurality of sections, and calculating keratometry measurement of the plurality of sections of the cornea to obtain curvatures of the plurality of sections by a preset algorithm; (C): using a lens manufacturing machine to produce the orthokeratology lens based on the curvatures of the plurality of sections, wherein the alignment curve of the lens comprises a plurality alignment sections matching the curvatures of the plurality of sections.
5. The method according to claim 4, wherein the electronic device in the step (B) is a desktop computer, a notebook computer, or an industrial computer.
6. The method according to claim 4; wherein the amount of the plurality of alignment sections of the alignment curve in the step (B) is even number.
7. The method according to claim 4, wherein the curvature of nasal alignment curve of the orthokeratology lens is lower than the temporal curvature of the alignment curve of the orthokeratology lens.
8. The method according to claim 4, wherein the step (B) comprises: using the electronic device to divide the alignment region of the cornea into eight sections; and during the dividing process, first, dividing the alignment region of the cornea into four sections based on X axis and Y axis, and then dividing each of the four sections by 45 degrees, so as to divide the alignment region into the eight sections, and use the eight sections to make the alignment curve of the lens form the eight sections, thereby improving lens-corneal alignment.
9. The method according to claim 4, wherein in the step (B), the electronic device uses a central point of the cornea of the eyeball as an original point of a X and Y coordinate system, the preset algorithm is expressed as:
10. The method according to claim 4, wherein the lens production machine in the step (C) is an aspheric surface manufacturing machine used to produce the orthokeratology lens by an aspheric surface production manner.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The structure, operating principle and effects of the present invention will be described in detail by way of various embodiments which are illustrated in the accompanying drawings.
[0010]
[0011]
[0012]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] The following embodiments of the present invention are herein described in detail with reference to the accompanying drawings. These drawings show specific examples of the embodiments of the present invention. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. It is to be acknowledged that these embodiments are exemplary implementations and are not to be construed as limiting the scope of the present invention in any way. Further modifications to the disclosed embodiments, as well as other embodiments, are also included within the scope of the appended claims. These embodiments are provided so that this disclosure is thorough and complete, and fully conveys the inventive concept to those skilled in the art. Regarding the drawings, the relative proportions and ratios of elements in the drawings may be exaggerated or diminished in size for the sake of clarity and convenience. Such arbitrary proportions are only illustrative and not limiting in any way. The same reference numbers are used in the drawings and description to refer to the same or like parts. As used herein, the term “or” includes any and all combinations of one or more of the associated listed items.
[0014] It will be acknowledged that when an element or layer is referred to as being “on,” “connected to” or “coupled to” another element or layer, it can be directly on, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present.
[0015] In addition, unless explicitly described to the contrary, the Word “comprise” and variations such as “comprises” or “comprising”, will be acknowledged to imply the inclusion of stated elements but not the exclusion of any other elements.
[0016] Please refer to
[0017] Furthermore, a preset curvature of the base curve 11 of the lens 1 is higher than a horizontal curvature of the cornea 21 of the eyeball 2, that is, the curvature of the base curve 11 is flatter than the horizontal curvature of the cornea 21; since the curvature of the base curve 11 is higher than the curvature of the cornea 21, when the lens 1 is worn on the eyeball 2, a positive pressure can be applied on epithelial cells of the cornea 21 by tears sandwiched between the base curve 11 and the cornea 21. Furthermore, the reverse curve 12 of the lens 1 forms a tear reservoir, so that a negative pressure applied by the tears can be used to improve effect of aligning the lens 1 on the eyeball 2.
[0018] In a preferable design, the peripheral curve 14 of the lens 1 edge lift can facilitate to squeeze out tears during blinking, to promote the tear exchange inside the lens 1, thereby continuously lubricating the contact area between the lens 1 and the cornea 21 of the eyeball 2 and delivering oxygen. Therefore, with the tear circulation, the orthokeratology lens of the present invention can provide better wearability and comfort when they wear ortho-k lenses.
[0019] The nasal curvature of the alignment curve 13 of the lens 1 is lower than the temporal curvature of the alignment curve 13 of the lens 1.
[0020] Furthermore, the inner surface of the lens 1 is aspheric.
[0021] The practical process of producing the lens 1 of the present invention can include the following steps.
[0022] In a step (A), a cornea topography is used to measure the cornea 21 of the eyeball 2, to obtain keratometry measurements of the cornea 21.
[0023] In a step (B), an electronic device is used to perform a calculation of curvature for the cornea 21 of the eyeball 2, and the alignment region 211, which matches the alignment curve 13 of the lens 1 to be produced, of the cornea 21 is divided into a plurality of sections 2111, and the keratometry measurements of the plurality of sections 2111 of the cornea 21 are calculated to obtain curvatures of the plurality of sections by a preset algorithm.
[0024] In a step (C), a lens production machine is used to produce the lens 1 based on the curvatures of the plurality of sections 2111, to produce the lens 1 with the alignment curve 13 having a plurality of alignment sections 131 matching the curvatures of the plurality of sections 2111, thereby completing production of the lens 1.
[0025] It should be noted that the manner of using the cornea topography to measure the cornea 21 of the eyeball 2 to obtain the keratometry measurement of the cornea 21 in the step (A) is a conventional art, so the details of internal electronic component and circuit design of the manner are not repeated herein.
[0026] Furthermore, the electronic device used in the step (B) can be, a desktop computer, a notebook computer, an industrial computer, or other electronic device with calculation function.
[0027] In the step (B), the electronic device can divide the alignment region 211 of the cornea 21 into the eight sections 2111; for example, during the dividing process, the alignment region 211 of the cornea 21 can be divided into four sections 2111 based on X axis and Y axis first, and each of the four sections is then divided by 45 degrees, so as to divide the alignment region 211 into the eight sections 2111; the eight sections 2111 can be mapped to the alignment curve 13 of the lens 1 to form the eight alignment sections 131 on the alignment curve 13 correspondingly, thereby using the eight alignment sections 131 to improve lens-corneal alignment.
[0028] In the step (B), the electronic device can use the central point of the cornea 21 of the eyeball 2 as the original point (0,0) of (X, Y) coordinate system, and the preset algorithm can be expressed as:
[0029] wherein z indicates a distance from the original point in the Y direction, c indicates a curvature of the central point of the cornea 21, r indicates a distance from the original point in the X direction, and k indicates asphericity, k=−e.sup.2, and e indicates eccentricity.
[0030] Furthermore, the lens manufacturing machine used in the step (C) can be an aspheric surface manufacturing machine to produce the lens 1 by an aspheric surface production manner. It should be noted that the lens manufacturing machine includes a lot of internal devices and components which are not key point of the present invention, so their detailed descriptions are not repeated herein.
[0031] When a user wants to wear the lens of the present invention, an optometrist can use the corneal topography to measure the cornea 21 of the wearer's eyeball 2 to obtain keratometry measurement of the wearer's cornea 21; the corneal topography can transmit the keratometry measurement to the electronic device, and at this time, an optometrist can use the electronic device to perform calculation of curvature, to divide the alignment region 211, which matches the alignment curve 13 of the lens 1 to be produced, of the cornea 21 into the sections 2111, and then calculate the keratometry measurement of the sections 2111 of the cornea 21 to obtain the curvatures of the sections 2111 by the preset algorithm. Next, the electronic device can transmit the curvatures of the cornea 21 to the lens manufacturing machine, and the lens manufacturing machine can produce the lens 1 based on the curvatures of the sections 2111, so that the alignment curve 13 of the lens 1 can have the alignment sections 131 matching with the curvatures of the sections 2111. When the wearer wears the produced lens 1 on the eyeball 2 thereof; the inner surface of the lens 1 can contact the surface of the cornea 21 of the eyeball 2; since the alignment curve 13 is formed with the alignment sections 131 matching the curvatures of the cornea 21, the lens 1 can be stably aligned with the eyeball 2. When the wearer goes to bed at night and closes eyelids (not shown in figures), the lens 1 can not decenter easily, and tears sandwiched between the base curve 11 of the lens 1 and the cornea 21 can indeed apply a positive pressure on epithelial cells on the central part of the surface of the cornea 21 of the eyeball 2, the epithelial cells on the surface of the cornea 21 can be pressed by the tears to make the curvature of the central cornea 21 gradually become flatter, to further make the central corneal epithelium become thinner, so as to reduce refractive power of the cornea 21 and move the image focus point toward the retina (not shown in figures) of the eyeball 2, thereby achieving the effect of improving stability of reduction or elimination of myopia.
[0032] The present invention disclosed herein has been described by means of specific embodiments. However, numerous modifications, variations and enhancements can be made thereto by those skilled in the art without departing from the spirit and scope of the disclosure set forth in the claims.