CN108652789A - The full visual range diffraction artificial lens that near vision is reinforced - Google Patents

Abstract

The invention discloses a kind of diffraction artificial lens, it includes diffraction structure area and refraction structure area, and diffraction structure area includes the first diffraction structure area, the second diffraction structure area and third diffraction structure area being sequentially distributed from the center of the optical surface of artificial lens to edge；First diffraction structure area includes for regarding the first remote diffraction focus and for regarding the second close diffraction focus；Second diffraction structure area include for regarding remote third diffraction focus, in the 4th diffraction focus and for regarding the 5th close diffraction focus；Third diffraction structure area include for regarding the 6th remote diffraction focus, in the 7th diffraction focus and for regarding the 8th close diffraction focus.First diffraction focus, third diffraction focus, the 6th diffraction focus, the focus of refracting sphere overlap；4th diffraction angle point, the 7th diffraction focus overlap；Second diffraction focus, the 5th diffraction focus, the 8th diffraction focus overlap.I.e. entire Crystallization depending on it is remote, regard in, regard nearly three focuses.

Description

Full range diffractive intraocular lens with enhanced near vision

technical field

The invention relates to the field of medical devices, and more specifically relates to a full-range diffractive intraocular lens with enhanced near-distance vision.

Background technique

In related technologies, after cataract surgery, the diffractive intraocular lens that replaces the natural lens makes the incident light converge on different diffraction orders through the diffraction effect on light, and different diffraction orders correspond to different crystal powers. Diffraction crystals can produce 2 or more than 2 focal points, which enables patients not only to see far away, but also to achieve vision requirements for other distances, thereby getting rid of the patient's need for glasses (patients implanted with aspheric single focus lenses can see Nearby, such as reading newspapers, etc., all need glasses). Through the adjustment of the diffraction structure, the energy distribution on different diffraction orders can be realized, thereby adjusting the effects of near vision/intermediate vision/distance vision. The current diffractive IOLs are basically designed based on the idea of synchronous energy dispersion when adjusting the diffraction structure. However, due to the synchronous dispersion of energy, the imaging effect of each focal point will deteriorate, and the imaging contrast will decrease. influence each other.

Contents of the invention

The present invention aims to solve at least one of the technical problems existing in the related art. Therefore, the present invention needs to provide a diffractive artificial lens.

A diffractive artificial lens according to an embodiment of the present invention includes a diffractive structure area and a refraction structure area, the diffractive structure area is located in the central area of the optical surface of the diffractive artificial lens, the refraction structure area is connected to the edge of the diffractive structure area, the The diffraction structure area includes a first diffraction structure area, a second diffraction structure area and a third diffraction structure area distributed sequentially from the central area to the edge of the optical surface of the artificial lens;

The first diffractive structure zone includes a first diffractive focus for distance vision and a second diffractive focus for near vision;

The second diffractive structure zone includes a third diffractive focus for distance vision, a fourth diffractive focus for central vision and a fifth diffractive focus for near vision;

The third diffractive structure zone includes a sixth diffractive focus for distance vision, a seventh diffractive focus for central vision, and an eighth diffractive focus for near vision.

In the above-mentioned diffractive intraocular lens, the fifth diffraction focus of the second diffraction structure zone, the eighth diffraction focus of the third diffraction structure zone and the second diffraction focus of the first diffraction structure zone are all used for near vision, so that the second diffraction structure zone The energy distribution of the fifth diffraction focus of the first diffraction structure area and the eighth diffraction focus of the third diffraction structure area is on the second diffraction focus of the first diffraction structure area. In this way, the energy utilization rate in the diffraction interval is improved, and the contrast of imaging is enhanced.

Among them, the first diffraction focus point, the third diffraction focus point, the sixth diffraction focus point, and the focus of the refraction area are coincident for the far-sighted; The second diffraction focus, the fifth diffraction focus and the eighth diffraction focus overlap. That is to say, the whole crystal forms three focal points as far-sighted, middle-sighted and near-sighted.

Further, as the pupil increases, the first diffraction structure area, the second diffraction structure area, the third diffraction structure area, and the refraction structure area are gradually exposed, and as the pupil increases, the visual focus gradually transitions from near vision to distance vision This is also consistent with the actual physiological and living conditions, thereby improving the visual effect.

In some embodiments, the region of refractive structure is used for distance vision.

In some embodiments, the second diffraction focus is the +1st order diffraction focus of the first diffraction structure region, and the first diffraction focus is the 0th order diffraction focus of the first diffraction structure region.

In some embodiments, the fourth diffraction focus is the +1st order diffraction focus of the second diffraction structure area, the fifth diffraction focus is the +2nd order diffraction focus of the second diffraction structure area, and the third diffraction focus is the 0th order diffraction focus of the second diffraction structure region.

In some embodiments, the seventh diffraction focus is the +1st order diffraction focus of the third diffraction structure area, the eighth diffraction focus is the +2nd order diffraction focus of the third diffraction structure area, and the sixth diffraction structure is the 0th order diffraction focus of the third diffraction structure area.

In some embodiments, the additional degree D1 of the near-sighted diffraction focus is twice the additional degree D2 of the apparent diffraction focus, wherein D1≤6.5D.

In some embodiments, the ratio of the energy distribution of the diffraction focus of the second diffraction structure area and the third diffraction structure area to the viewing distance and the diffraction focus of the viewing distance is different; relative to the second diffraction structure area, the The ratio of the energy distribution of the diffraction focus in the third diffraction structure area is reduced while the energy distribution ratio of the diffraction focus in the distance is increased; the additional degree of the diffraction focus of the second diffraction structure area and the third diffraction structure area is close D1 is 2 times of the additional degree D2 of the diffraction focus in view; from the center of the optical surface to the edge of the optical surface, the energy distribution ratio of the diffraction focus of the first diffraction structure area and the viewing distance of the third diffraction structure area is always the same. Greater than 40%.

In some embodiments, the mth diffraction focus for far vision and the focus of the refraction zone coincide with each other; the mth diffraction focus for vision coincides with each other; the mth diffraction focus for near vision coincides with each other. That is to say, the entire crystal optical surface forms three focal points of distance vision, middle vision and near vision.

In some embodiments, the diffractive structure zone includes n diffractive surface types arranged concentrically, and the n diffractive surface types are distributed sequentially from the optical central zone to the edge of the diffractive intraocular lens, and the first diffractive structure zone has a first Up to 2u such diffraction surface types, u=1 or 2;

The second diffractive structure region has (2u+1) to (2u+1+k)th diffractive surface types, k=0 or 1;

The third diffractive structure region has (2u+1+k+1)th to nth diffractive surface types, n≥(2u+1+k+1), and n is a natural number.

In some embodiments, the 1st to 2uth diffractive surface types have an optical path difference equal to λ/2, and the (2u+1) to (2u+1+k)th diffractive surface types have an optical path difference equal to or greater than λ /2 optical path difference, the (2u+1+k+1)th to nth diffraction surface types have an optical path difference smaller than λ/2.

In some embodiments, the actual height of each diffractive surface type meets the design height: h _i+1 '=h _i+1 *f _i+1 , where h _i+1 'indicates the diffractive surface type h _i+1 represents the design height of the diffraction surface type, f _i+1 represents the coefficient related to the design height of the diffraction surface type and the radius of the cutter head for processing the diffraction surface type, and i represents the diffraction surface type The serial number of i=1,2,...,n.

In some embodiments, the actual degree and design degree of each diffraction structure area of the first diffraction structure area, the second diffraction structure area and the third diffraction structure area meet the condition: P _i+1 '=P _{i +1} *f _i+1 , wherein, P _i+1 'indicates the actual degree of the diffraction structure, P _i+1 indicates the design degree of the diffraction structure, f _i+1 indicates the design height and processing of the diffraction surface The coefficient related to the cutter head radius of the diffractive surface type, i represents the serial number of the diffractive surface type, i=1, 2,...,n.

In some embodiments, the optical profile of the refractive structure zone is the surface basaloid of the diffractive IOL.

In some embodiments, the diffractive intraocular lens includes a first face and a second face opposite to each other, at least one of the first face and the second face has the diffractive structure region and the refractive structure region.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and comprehensible from the description of the embodiments in conjunction with the following drawings, wherein:

Fig. 1 is a schematic plan view of a diffractive artificial lens according to an embodiment of the present invention;

Fig. 2 is a partial cross-sectional schematic diagram of a diffractive intraocular lens according to an embodiment of the present invention;

Fig. 3 is a schematic diagram of the processing of the diffractive surface of the diffractive artificial lens according to the embodiment of the present invention;

4 is a schematic structural view of a cutter for processing a diffractive surface of a diffractive artificial lens according to an embodiment of the present invention;

Fig. 5 is an energy distribution diagram of each focal point corresponding to each diffraction surface type of the diffractive intraocular lens according to the embodiment of the present invention;

Fig. 6 is an energy distribution diagram of each focal point in the pupil aperture when the diffractive intraocular lens according to the embodiment of the present invention is applied.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the terms "first" and "second" are used for description purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of said features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; may be mechanically connected, may be electrically connected or may communicate with each other; may be directly connected, or indirectly connected through an intermediary, may be internal communication between two components or interaction between two components relation. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, components and configurations of specific examples are described below. Of course, they are only examples and are not intended to limit the invention. Furthermore, the present disclosure may repeat reference numerals and/or reference letters in different instances, such repetition is for the purpose of simplicity and clarity and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed. In addition, various specific process and material examples are provided herein, but one of ordinary skill in the art may recognize the use of other processes and/or the use of other materials.

Referring to Fig. 1 and Fig. 2, a diffractive IOL 100 according to an embodiment of the present invention includes a diffractive structure area 102 and a refraction structure area 104, the diffractive structure area 102 is located in the central area of the optical surface of the diffractive IOL 100, the The refraction structure area 104 is connected to the edge of the diffraction structure area 102, and the diffraction structure area 102 includes a first diffraction structure area 106, a second diffraction structure area 108 and a first diffraction structure area 108 distributed sequentially from the center area of the optical surface of the artificial lens to the edge. Three diffractive structure regions 110;

The first diffractive structure area 106 includes a first diffractive focus for distance viewing and a second diffractive focus for near viewing;

The second diffractive structure area 108 includes a third diffractive focal point for far vision, a fourth diffractive focal point for central vision and a fifth diffractive focal point for near vision;

The third diffractive structure region 110 includes a sixth diffractive focus for distance vision, a seventh diffractive focus for central vision and an eighth diffractive focus for near vision.

In the above-mentioned diffractive intraocular lens 100, the fifth diffraction focus of the second diffraction structure area 108, the eighth diffraction focus of the third diffraction structure area 110 and the second diffraction focus of the first diffraction structure area 106 are all used for near vision, so that the first The energy distribution of the fifth diffraction focus of the second diffraction structure area 108 and the eighth diffraction focus of the third diffraction structure area 110 is on the second diffraction focus of the first diffraction structure area 106 . In this way, the energy utilization rate in the diffraction interval is improved, and the contrast of imaging is enhanced.

Among them, the first diffraction focus point, the third diffraction focus point, the sixth diffraction focus point, and the focus of the refraction area are coincident for the far-sighted; The second diffraction focus, the fifth diffraction focus and the eighth diffraction focus overlap. That is, the entire crystal 100 forms three foci of far vision, intermediate vision and near vision.

Further, as the pupil increases, the first diffraction structure area 106, the second diffraction structure area 108, the third diffraction structure area 110, and the refraction structure area 104 are gradually exposed. The transition from increasing vision distance to intermediate vision, increasing distance vision and then to distance vision is also consistent with the actual physiological and living conditions, thereby improving vision.

Specifically, the restoration of vision after cataract is mainly aimed at seeing distance, so distance vision is the most important vision. The distance vision can run through the entire optical surface of the diffractive intraocular lens 100, including the first diffraction focus, the third diffraction focus and the sixth diffraction focus of the diffraction structure region 102, and these three diffraction focuses coincide.

For near-distance vision, when looking close, the light intensity is relatively strong, and the pupil shrinks at this time, so the near-distance vision should be set within the small pupil range. interference, while the focus imaging spot of long-distance vision is large, and it will not affect near-distance imaging at this time.

For intermediate distance vision, the intermediate distance vision is centered relative to ground in the diffractive structure regions 108 and 110, namely the fourth and seventh diffractive foci. In the second diffractive structure region 108 and the third diffractive structure region 110 , the energy distribution of the central focal point is less than or equal to the energy of the apparent far focal point. For near vision, the pupil will expand compared to near vision. At this time, the near vision area has a small area, so the energy of the near vision focus is relatively small, and the near vision functional area of the crystal optical surface is concentrated in the small pupil area. The generated light spot is small, so the impact on the imaging quality of the field of view is small. When looking in the center, within the scope of the dilated pupil, it is the light spot formed on the retina by the focus of the center of vision that plays a leading role in imaging.

For middle-distance vision, the light passing through the far focus will have an impact on the middle-distance vision: the light passing through the far focus may cause a large light spot due to the large diameter of the incident light edge, but the focus difference between the middle and the far focus is relatively small. Small, so the interference spot signal generated by the far focal point is small, which is reflected in the large depth of focus without causing a serious decline in imaging quality.

Therefore, the diffractive IOL 100 according to the embodiment of the present invention can realize the full-range diffractive IOL 100 with enhanced near vision.

In addition, the outer edge of the refractive structure region 104 of the diffractive intraocular lens 100 in the embodiment of the present invention is connected with two spaced support walls 112, and the two support walls 112 are used to install the diffractive intraocular lens 100 in the eye. In some embodiments, the support wall 112 is a flexible support wall 112 .

It should be pointed out that the "for distance vision" mentioned in the embodiment of the present invention means that the diffraction structure region 102 of the crystal converges the light on the distance vision focal point. "For central vision" and "for near vision" are similarly interpreted. "Sequentially distributed" in the embodiment of the present invention means that the second diffractive structure region 108 is connected to the outer edge of the first diffractive structure region 106 , and the third diffractive structure region 110 is connected to the outer edge of the second diffractive structure region 108 .

In some embodiments, the refractive structure region 104 is used for distance vision.

In this way, the distance vision of the distance vision diffractive IOL 100 can be further enhanced.

Specifically, the refraction structure region 104 can be used as an edge refraction region, converging 100% of the light passing through this region to the far focal point. The outgoing light of the refraction structure area 104 is collected at the far focal point, that is, the 0th order diffraction focus of the diffraction structure area 102 .

In some embodiments, the optical surface of the refractive structure region 104 is the base curve of the diffractive IOL 100 . In this way, the refractive structure region 104 has no additional degree and is easy to manufacture, thereby reducing the cost of the diffractive IOL 100 .

In some embodiments, the second diffraction focus is the +1st order diffraction focus of the first diffraction structure region 106 , and the first diffraction focus is the 0th order diffraction focus of the first diffraction structure region 106 .

In this way, the energy used for distance vision is relatively high, which ensures that the distance vision of the diffractive IOL 100 can meet the requirements, while also taking into account the requirements for near vision.

Specifically, the +1-order diffraction focus of the first diffraction structure area 106 is used for near vision, and the additional degree is +P ₁ D. In some embodiments, +P ₁ D can be set to +2.0 to +6.5D, For example, +P ₁ D=+2.0D, +P ₁ D=+3.0D, +P ₁ D=+3.5D, or +P ₁ D=+5.0D, etc.

In some embodiments, the fourth diffraction focus is the +1st order diffraction focus of the second diffraction structure area 108, the fifth diffraction focus is the +2nd order diffraction focus of the second diffraction structure area 108, and the third The diffraction focus is the 0th order diffraction focus of the second diffraction structure region 108 .

In this way, the energy used for distance vision is relatively high, ensuring that the distance vision of the diffractive IOL 100 can meet the requirements, and at the same time, it is allocated according to different application scenarios of near vision and mid vision, making the design of the second diffractive structure area 108 more efficient. Reasonably, further, the +2nd-order diffraction energy of the second diffraction structure can just fall on the near-sight focus, which can also minimize energy loss.

Specifically, the +1st-order diffraction focal point of the second diffraction structure region 108 is used for viewing center, and the additional degree is +P ₂ D, where 2P ₂ =P ₁ , and P ₁ is the additional degree of near vision. The second diffractive structure area 108 is located on the outer edge of the first diffractive structure area 106 .

In some embodiments, the additional degree D1 of the near-sighted diffraction focus is twice the additional degree D2 of the apparent diffraction focus, wherein D1≤6.5D.

In this way, the energy distribution of the diffractive IOL 100 is reasonable.

In some embodiments, the seventh diffraction focus is the +1st order diffraction focus of the third diffraction structure area 110, the eighth diffraction focus is the +2nd order diffraction focus of the third diffraction structure area 110, and the sixth The diffraction structure is the 0th order diffraction focus of the third diffraction structure area 110 .

In this way, the energy used for distance vision is relatively high, ensuring that the distance vision of the diffractive IOL 100 can meet the requirements, and at the same time, it is allocated according to different application scenarios of near vision and mid vision, making the design of the third diffractive structure area 110 more efficient. Reasonably, further, the +2nd-order diffraction energy of the third diffraction structure can just fall on the near-sight focus, which can also minimize energy loss.

Specifically, the +1st-order diffraction focal point of the third diffraction structure region 110 is used for viewing center, and the additional degree is +P ₂ D, where 2P ₂ =P ₁ , and P ₁ is the additional degree of near vision. The third diffractive structure region 110 is located at the outer edge of the second diffractive structure region 108 and extends to the end of the diffractive structure region 102 .

In some embodiments, the diffractive structure region 102 includes n diffractive surface types arranged concentrically, and the n diffractive surface types are distributed sequentially from the optical central region to the edge of the diffractive intraocular lens 100. The first diffractive structure region 106 Having the 1st to 2uth diffraction surface types, u=1 or 2;

The second diffractive structure region 108 has (2u+1) to (2u+1+k)th diffractive surface types, k=0 or 1;

The third diffractive structure region 110 has (2u+1+k+1) to nth diffractive surface types, n≥(2u+1+k+1), n is a natural number.

In this way, the corresponding diffractive structure function is realized through the assignment of the facet type.

Specifically, please refer to Fig. 2, n diffractive surface types are distributed from the central region to the edge of the optical surface of the diffractive IOL 100, which are the first diffractive surface type, the second diffractive surface type, the third diffractive surface type, ... , the i-th diffraction surface type, ..., the n-th diffraction surface type. Each diffractive surface type is convex relative to the base curve of the diffractive IOL 100 .

It should be noted that when k=0, it means that the second diffraction structure region 108 has a 2u+1th diffraction surface type. When n=2u+1+k+1, it means that the third diffractive structure region 110 has the 2u+1+k+1th diffractive surface type or the nth diffractive surface type.

In one example, u=2, k=0, n=6, then the first diffractive structure region 106 has the first to fourth diffractive surface types, that is, the first diffractive surface type, the second diffractive surface type, The third diffraction surface type and the fourth diffraction surface type, a total of 4 diffraction surface types. The second diffractive structure region 108 has a fifth diffractive surface type, and the third diffractive structure region 110 has a sixth diffractive surface type.

In another example, u=2, k=1, n=8, then the first diffractive structure area 106 has the first to fourth diffractive surface types, that is, the first diffractive surface type and the second diffractive surface type , the third diffraction surface type and the fourth diffraction surface type, a total of 4 diffraction surface types. The second diffractive structure area 108 has 5th to 6th diffractive surface types, ie, the 5th diffractive surface type and the 6th diffractive surface type, a total of 2 diffractive surface types. The third diffractive structure area 110 has 7th to 8th diffractive surface types, that is, the 7th diffractive surface type and the 8th diffractive surface type, and there are 2 diffractive surface types in total.

In some embodiments, the 1st to 2uth diffractive surface types have an optical path difference equal to λ/2, and the (2u+1) to (2u+1+k)th diffractive surface types have an optical path difference equal to or greater than λ /2 optical path difference, the (2u+1+k+1)th to nth diffraction surface types have an optical path difference smaller than λ/2.

In this way, the energy distribution of the far-sighted and near-sighted areas of the first diffractive structure region 106 can be realized to be 1:1, and the energy distribution of the second diffractive structure region 108 can be realized to be 1:1 or greater than 1:1. , and the energy of the fifth diffraction focus (such as +2-order diffraction focus) falling on the near focus is about 4.5% or less than 4.5%, so that the near vision ability is further strengthened, and the vision of the third diffraction structure area 110 can be realized. The energy distribution of medium and far vision is less than 1:1 (such as 1:3 or 1:2, etc.); the energy of the eighth diffraction focus (such as +2 diffraction focus) falling on the near focus is less than 4.5% (or 3.2 %), so that the near vision ability is further strengthened. To sum up, the diffractive IOL 100 improves energy utilization efficiency and reduces energy loss.

In addition, about 19% of the energy of the first diffraction structure region 106 is distributed on the higher-order diffraction, which can be regarded as a lost energy ratio because it cannot be effectively used. About ≤15% of the energy of the second diffractive structure region 108 is distributed on the higher-order diffraction, which can be regarded as a lost energy ratio because it cannot be effectively utilized. For the third diffractive structure region 110, about ≤15% of the energy is distributed on the higher-order diffraction, which can be regarded as a lost energy ratio because it cannot be effectively utilized.

In certain embodiments, processing factors are introduced into the IOL design. Due to the limitation of the cutting tool of the processing equipment (for example, the cutting head of the processing tool cannot be a theoretical point, and the step (step) formed for the diffraction surface type cannot become a theoretical sharp angle, as shown in Figure 3), therefore, the actual There are differences between the processed diffractive surface structure and the theoretical structure. Therefore, in order to combine theoretical design with actual processing in the design, so as to better control the optical performance of the product, in the embodiment of the present invention, a processing factor is introduced.

Specifically, the actual height of each diffractive surface conforms to the design height: h _i+1 '=h _i+1 *f _i+1 , where h _i+1 ' represents the actual height of the diffractive surface, h _i+1 represents the design height of the diffraction surface type, f _i+1 represents the coefficient related to the design height of the diffraction surface type and the radius of the cutter head for processing the diffraction surface type, i represents the serial number of the diffraction surface type, i =1,2,...,n.

In this way, f _i+1 can be used as a processing factor to correct the height of the diffraction surface.

More specifically, please combine Figure 1, Figure 2 and Figure 4, the processing factor f _i+1 can be determined by the following formula: Among them, w ² ＝R _t ² -(R _t -h) ² ＝2R _t *hh ² ≈2R _t *h, R _t represents the radius of the machining tool head, h represents the height of the diffraction surface, r _i is the first The radius of the i diffraction surface (see Figure 1 and Figure 2).

In Figure 4, OA is the theoretical step shape of each diffraction surface, and the step height h is equal to the length of the line segment OA. However, due to the influence of the radius of the cutter head, the actual step shape of the diffraction surface is an arc OB.

In some embodiments, the actual degree and design degree of each diffraction structure region 102 of the first diffraction structure region 106, the second diffraction structure region 108 and the third diffraction structure region 110 meet the condition: P _i+1 '=P _i+1 *f _i+1 , wherein, P _i+1 ' represents the actual degree of the diffraction structure region 102, P _i+1 represents the design degree of the diffraction structure region 102, and f _i+1 represents the degree of integration with the diffraction structure region 102 The coefficient related to the design height of the diffractive surface and the radius of the cutter head for processing the diffractive surface, i represents the serial number of the diffractive surface, i=1,2,...,n.

In this way, f _i+1 can be used as a processing factor to correct the degree of the diffractive structure region 102 .

Specifically, the processing factor f _i+1 may also be determined by the above implementation manner. In an embodiment of the present invention, a processing factor may be used to correct for the +1st order diffraction power.

In some embodiments, the diffractive intraocular lens 100 includes a first face 114 and a second face opposite to each other, the first face 114 has the diffractive structure region 102 and the refractive structure region 104 .

Specifically, in one example, when the diffractive intraocular lens 100 is installed in the eye, the first surface 114 is the surface facing the outside of the eye, and the second surface is the surface facing the inside of the eye and attached to the posterior capsule.

In other embodiments, the second surface has the diffractive structure region 102 and the refractive structure region 104 , or both the first surface 114 and the second surface have the diffractive structure region 102 and the refractive structure region 104 .

Embodiments of specific planar structures of the diffractive structure region 102 of the diffractive intraocular lens 100 according to the embodiment of the present invention will be described below.

Let the degree of diffractive IOL 100 be P, set the additional degree of near-sight diffraction of the crystal as +P ₁ degree (can be set to +2.0 to +5.0D); set the apparent degree of crystal as +P ₂ degrees, and 2P ₂ = P ₁ .

In one example, crystal degrees P, P1, and P2 are all for the wavelength of λ=546 nm, and the refractive index n ₁ of the crystal and the medium refractive index n ₂ are for the wavelength of λ=546 nm.

(1). The basic contour corresponding to the basic degree (base curve)

The basic profile surface type is the surface type of the base arc surface, the surface type of the base arc surface corresponds to the radius of curvature R, the aspheric surface coefficient K, the high-order aspheric surface coefficient, etc. The surface shape of the base arc surface is consistent with the design of the aspheric artificial lens . The basic degree P corresponds to the aspheric crystal, as shown in the base curve in Figure 2.

(2). Optical division

The effective optical zone of the crystal is 5.0mm-6.0mm (diameter);

① The first diffraction structure area 106

The first diffractive structure zone 106 is located at the central zone position of the optical surface of the diffractive intraocular lens 100. The main function of this zone is to see far and see near, with 2 (Zone1 and Zone 2 as shown in Figure 2) or 4 diffractive Zone (Zone) (Zone 1 to Zone 4 in Figure 2), the number of Zones in this zone is an even number. The added degree of the crystal is +P ₁ degree.

in:

λ is the wavelength, here 546nm can be used;

r _i is the radius of the diffraction surface (as shown in Figure 2, it can be understood as the position of the step formed by the diffraction surface);

i=1, 2, 3, 4..., the serial number of the diffraction surface;

P ₁ is the first diffraction structure region of the crystal + the additional degree of first-order diffraction;

h _n is the height of the diffraction surface;

k ₁ is the optical path difference of light wave (546nm) at the diffraction step, equal to the optical path difference at all the diffraction steps in the first diffraction structure area;

n ₁ is the refractive index of the crystal material; n ₂ is the refractive index of the medium around the crystal.

In the first diffraction structure area 106, the 0th-order diffraction focus of the crystal falls on the far focus, and the effective degree is P; the +1-order diffraction focus falls on the near-vision focus, and the additional diffraction degree is P ₁ , the focus crystal The degree of expression of P ₁ + P; the additional degree of +2-order diffraction is 2P ₁ , at this time, the additional degree is too large, and the energy distribution is small, and the image cannot be recognized by the eyes, so +2-order and higher-order diffraction The focal point will not be used effectively, and this part of the energy will be regarded as a lost part in imaging.

The energy distribution of the 0-order, +1-order diffraction focus, and the energy distribution of higher diffraction orders are calculated according to the following calculation method (p in the formula represents the diffraction energy level, and η is the diffraction efficiency):

n

R(1) ² =2λ/P ₁ ;

Energy η _lost =1−η ₀ +η ₁ for unusable high diffraction orders.

②Second diffractive structure area 108

The second diffraction structure area 108 is next to the first diffraction structure area 106 , and the main function of the second diffraction structure area 108 is distance vision and center vision. Suppose the quantity of the diffraction surface type of the first diffraction structure area 106 is m (even number), then the first diffraction surface type of the second diffraction structure area 108 is the m+1th diffraction surface type of the whole diffraction structure area 102, and the diffraction The additional degree of +1 order diffraction of structured region 108 is +P ₂ degrees.

P ₂ is the crystal degree of the second diffraction structure region 108 + the additional degree of first-order diffraction, 2P ₂ =P ₁ ;

m is the number of diffraction surface types of the first diffraction structure area 106;

k ₂ is the optical path difference of light wave (546nm) at the diffraction step, and is equal to the optical path difference at all diffraction steps in the second diffraction structure area;

Other symbols are consistent with the formulas corresponding to the first diffraction structure region 106 .

The energy distribution of the diffraction energy levels of the second diffraction structure region 108 follows the calculation method of the first diffraction structure region 106 . However, the equivalent lens power produced by the +2-order diffraction of the second diffraction structure area 108 is 2P ₂ , that is, P1, that is, the +2-order diffraction energy produced by the second diffraction structure area 108 can be effectively utilized and converged at the near focal point. It coincides with the +1st order diffraction focus of the first diffraction structure area. According to the different heights of the steps of the diffractive surface, different proportions of the +2nd order diffracted energy will be collected at the near focal point. Therefore, the energy efficiency of the second diffractive structure region 108 is high.

The calculation method of η ₀ , η ₁ , and η ₂ is the same as that of the first diffraction structure region 106, except that R(1) ² =2λ/P ₂ .

η _lost = 1-η ₀ -η ₁ -η ₂ .

③ The third diffraction structure area 110

Next to the second diffractive structure region 108 , the main functions of the third diffractive structure region 110 are distance vision and central vision. The far-sighted energy distribution in the third diffractive structure region 110 should be stronger than the apparent central energy distribution. Assume that the number of diffractive surface types of the first diffractive structure region 106 is m (even number). Since the apparent additional degree of the third diffractive structure area 110 is consistent with that of the second diffractive structure area 108 , the step position of each diffractive surface type of the third diffractive structure area 110 still obeys the formula in the second diffractive structure area 108 . The crystal has an additional degree of +P ₂ degrees.

P2 is the crystal power of the _second diffraction structure region 108 + the additional power of the first-order diffraction;

m is the number of diffraction surface types of the first diffraction structure area 106;

K ₃ is the optical path difference of the light wave (546nm) on the diffraction surface, which is not equal to K ₂ .

The difference between the third diffractive structure area 110 and the second diffractive structure area 108 is the difference in the energy distribution at the two focal points of the view center and the view distance. According to the different heights of the steps of the diffractive surface, different proportions of the +2nd order diffracted energy will be collected at the near focal point. The calculation method of η ₀ , η ₁ , and η ₂ is the same as the calculation method of the second diffraction structure area 108 .

η _lost = 1-η ₀ -η ₁ -η ₂ .

④ Refractive structure area 104

The refraction structure region 104 is also called the edge refraction region, which converges the light rays to the far focal point. The optical profile of the refractive structure region 104 is the base curve of the surface of the diffractive IOL 100 , which has no additional degrees.

The outgoing light of the refraction structure area 104 is collected at the far focal point, that is, the 0th order diffraction focus of the diffraction structure area 102 .

The diffractive intraocular lens 100 according to the embodiment of the present invention will be described below with specific examples.

Firstly, the optical zone of the diffractive IOL 100 is divided into a diffractive structure zone 102 and a refractive structure zone 104 . In this example, the refractive index n ₁ of the material of the diffractive artificial lens 100 at 546 nm is 1.5202, and the refractive index n ₂ of the medium surrounding the crystal is 1.336.

1) The first diffraction structure area 106

The +1 order diffraction degree of the first diffraction structure area 106 is +3.50D;

The first diffractive structure zone 106 has two diffractive surface types (Zone) located in the central area of the optical surface of the diffractive IOL 100, namely the first diffractive surface type Zone1 and the second diffractive surface type Zone2;

The energy distribution ratio of the 0th-order diffraction and the +1-order diffraction of the first diffraction structure area 106 is 1:1;

According to the above input, it can be known that:

r ₁ =0.5586mm; h ₀ =1.48um;

r ₂ =0.7899mm; h ₁ =1.48um;

η ₀ =41%; η ₁ =41%; η _lost =18%.

2) The second diffraction structure area 108

The +1 order diffraction degree of the second diffraction structure area 108 is +1.750D;

The +2nd order diffraction degree of the second diffraction structure area 108 is +3.50D;

The second diffractive structure area 108 has the third diffractive surface type Zone3 located in the central area of the crystal optical surface;

The energy distribution ratio of the 0th-order diffraction and the +1-order diffraction of the second diffraction structure area 108 is 1:1;

According to the above input, it can be known that:

r ₃ =1.1171mm; h ₂ =1.48um;

η ₀ =41%; η ₁ =41%; η ₂ =4.5%; η _lost =13.5%.

3) The third diffraction structure area 110

The +1 order diffraction degree of the third diffraction structure area 110 is +1.750D;

The +2nd order diffraction degree of the third diffraction structure area 110 is +3.50D;

The third diffraction structure area 110 has the 4th to 9th diffraction surface types located in the central area of the crystal optical surface;

The energy distribution ratio of the 0th-order diffraction and the +1-order diffraction of the third diffraction structure area 110 is 3:1;

According to the above input, it can be known that:

r ₄ =1.3682um; h ₃ =1.085um;

r ₅ =1.5798mm; h ₄ =1.085um;

r ₆ =1.7660mm; h ₅ =1.085um;

r ₇ =1.9349mm; h ₆ =1.085um;

r ₈ =2.0900mm; h ₇ =1.085um;

r ₉ =2.2234mm; h ₈ =1.085um;

η ₀ =63%; η ₁ =21%; η ₂ =3.2%; η _lost =12.8%.

4) Refractive structure area 104

The surface type of the refraction structure region 104 is the basic surface type parameter of the aspheric crystal.

The interval is from 2.2234mm to the edge of the optical zone (radius 3.0mm);

Its light converges at the far focal point through 100% refraction.

5) Introduction of processing factors

The processing factor mainly considers the difference between the actual surface shape and the theoretical surface shape caused by the limitation of the cutting tool in crystal production. The processing factor can well overcome the limitations of the processing factor.

Let the radius Rt of the cutter head be 0.100mm.

① For the diffraction structure of the first diffraction structure area 106:

w=17.205um;

Then f ₁ =(0.5586/(0.5586-0.017))^2=1.006;

Then h ₁ '=1.48um*1.006=1.49um;

P ₁ '=3.5D*1.006=3.52D.

② For the diffraction structure of the second diffraction structure area 108:

w=17.205um;

Then f ₁ =(0.7899/(0.7899-0.017))^2=1.004;

Then h ₁ '=1.48um*1.004=1.49um;

P ₁ '=1.75D*1.004=1.76D;

③ For the diffraction structure of the third diffraction structure area 110:

w=14.731um;

Then f ₁ =(0.7899/(0.7899-0.015))^2=1.004;

Then h ₁ '=1.085um*1.004=1.09um;

P ₁ '=1.75D*1.004=1.76D.

6) Calculation of energy distribution

The theoretical distribution of energy can be calculated according to the energy calculation method as described above.

①Individual energy distribution in each diffraction surface (please refer to Figure 5)

Table 1 Energy distribution of each focal point corresponding to each diffraction surface type (Zone)

②Total energy distribution within different pupil radii (please combine with Figure 6)

Table 2 Energy distribution of each focal point within the pupil aperture

Aperture r/mm 0.56 0.79 1.12 1.37 1.58 1.77 1.93 2.09 2.22 2.37 3.00 Far focus/% 41.0 41.0 41.0 48.3 52.0 54.2 55.7 56.7 57.5 62.2 76.4 Medium focus/% 0 0 20.5 20.7 20.8 20.8 20.8 20.9 20.9 18.6 11.6 Near focus/% 41.0 41.0 22.8 16.2 13.0 11.0 9.7 8.8 8.09 7.2 4.5 loss/% 18.0 18.0 15.8 14.8 14.3 14.0 13.8 13.6 13.5 12.0 7.5

To sum up, the diffractive intraocular lens 100 according to the embodiment of the present invention can satisfactorily meet the demands of far vision, near vision and central vision.

In the description of this specification, descriptions that refer to the terms "one embodiment," "certain embodiments," "exemplary embodiments," "examples," "specific examples," or "certain examples" are meant to be combined with The specific features, structures, materials, or characteristics described in the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the invention is defined by the claims and their equivalents.

Claims (13)

1. a kind of diffraction artificial lens, which is characterized in that including diffraction structure area and refraction structure area, which is located at The center of the optical surface of the diffraction artificial lens, the refraction structure area are connected to the edge in the diffraction structure area, the diffraction knot Structure area includes the first diffraction structure area being sequentially distributed from the center of the optical surface of the artificial lens to edge, the second diffraction knot Structure area and third diffraction structure area；

The first diffraction structure area includes for regarding the first remote diffraction focus and for regarding the second close diffraction focus；

The second diffraction structure area include for depending on remote third diffraction focus, for depending in the 4th diffraction focus and for regarding The 5th close diffraction focus；

The third diffraction structure area include for depending on the 6th remote diffraction focus, for depending in the 7th diffraction focus and for regarding The 8th close diffraction focus.

2. diffraction artificial lens as described in claim 1, which is characterized in that the refraction structure area is used to regard remote.

3. diffraction artificial lens as described in claim 1, which is characterized in that the second diffraction focus is first diffraction structure + 1 order diffraction focus in area, the first diffraction focus are the 0 order diffraction focus in the first diffraction structure area.

4. diffraction artificial lens as described in claim 1, which is characterized in that the 4th diffraction focus is second diffraction structure + 1 order diffraction focus in area, the 5th diffraction focus are+2 order diffraction focuses in the second diffraction structure area, and the third diffraction is burnt Point is the 0 order diffraction focus in the second diffraction structure area.

5. diffraction artificial lens as described in claim 1, which is characterized in that regard the additional number of degrees D1 of close diffraction focus as regarding In 2 times of additional number of degrees D2 of diffraction focus, wherein D1≤6.5D.

6. diffraction artificial lens as described in claim 1, which is characterized in that the 7th diffraction focus is the third diffraction structure + 1 order diffraction focus in area, the 8th diffraction focus are+2 order diffraction focuses in the third diffraction structure area, the 6th diffraction knot Structure is the 0 order diffraction focus in the third diffraction structure area.

7. diffraction artificial lens as described in claim 1, which is characterized in that spread out with the third in second diffraction structure area Structural area is penetrated to the diffraction focus, different regarding remote diffraction focus energy allocation proportion in；Relative to the second diffraction knot Structure area, third diffraction structure area reduce the diffraction focus energy distribution ratio in and divide regarding remote diffraction focus energy Cloth ratio improves；Second diffraction structure area and third diffraction structure area regard the additional number of degrees D1 of close diffraction focus as 2 times of the additional number of degrees D2 of diffraction focus depending in；From optical surface center to optical surface edge, first diffraction structure area and The energy allocation proportion depending on remote diffraction focus in third diffraction structure area is consistently greater than 40%.

8. diffraction artificial lens as described in claim 1, which is characterized in that the diffraction structure area includes n be arranged concentrically Diffraction surfaces type, the n diffraction surfaces type are sequentially distributed from the optical centre area of the diffraction artificial lens to edge, the first diffraction knot Structure area has the 1st to the 2u diffraction surfaces type, u=1 or 2；

The second diffraction structure area has (2u+1) to (2u+1+k) a diffraction surfaces type, k=0 or 1；

The third diffraction structure area has (2u+1+k+1) to the n diffraction surfaces types, and n >=(2u+1+k+1), n are natural number.

9. diffraction artificial lens as claimed in claim 8, which is characterized in that the 1st to the 2u diffraction surfaces type, which has, is equal to λ/2 Optical path difference, (2u+1) to (2u+1+k) a diffraction surfaces type have equal to or more than λ/2 optical path difference, (2u+1+k+1) There is the optical path difference less than λ/2 to the n diffraction surfaces types.

10. diffraction artificial lens as claimed in claim 8, which is characterized in that the actual height of each diffraction surfaces type with set Meter height is eligible：h_i+1'=h_i+1*f_i+1, wherein h_i+1' indicate the actual height of the diffraction surfaces type, h_i+1Indicate the diffraction The design height of face type, f_i+1The tip radius of expression with the design height and processing of the diffraction surfaces type diffraction surfaces type is relevant Coefficient, i indicate the serial number of the diffraction surfaces type, i=1,2 ..., n.

11. diffraction artificial lens as claimed in claim 8, which is characterized in that the first diffraction structure area, the second diffraction knot The practical number of degrees in each diffraction structure area in structure area and the third diffraction structure area and the design number of degrees are eligible：P_i+1'=P_i+1* f_i+1, wherein P_i+1' indicate the practical number of degrees of the diffraction structure, P_i+1Indicate the design number of degrees of the diffraction structure, f_i+1It indicates and is somebody's turn to do The design height of diffraction surfaces type and the relevant coefficient of tip radius for processing the diffraction surfaces type, i indicate the serial number of the diffraction surfaces type, I=1,2 ..., n.

12. diffraction artificial lens as described in claim 1, which is characterized in that the optical surface type in the refraction structure area spreads out for this Penetrate the surface base cabochon of artificial lens.

13. diffraction artificial lens as described in claim 1, which is characterized in that the diffraction artificial lens includes opposite first At least one side in face and the second face, first face and second face has the diffraction structure area and the refraction structure area.