A device for testing vision through an intraocular lens

Abstract

An apparatus (16) for testing visual acuity through an intraocular lens (8) has a support (17) that supports a corneal optical system (18), a mounting device (19) for the intraocular lens (8), and an ocular optical system (20) in that order from distal to proximal on a central visual axis (5), the ocular optical system (20) having a corrective lens (23) at its distal end and a diverging lens (24) and a converging lens (25) at its proximal end, the corrective lens (23) having a distal concave lens surface (26) and a proximal convex lens surface (27).

Description

[Technical Field]

[0001] The present invention relates to an apparatus for testing vision through an intraocular lens, the apparatus comprising a support for supporting a corneal optic, a mounting device for the intraocular lens, and an ocular optic, in that order from distal to proximal to the central visual axis. [Background technology]

[0002] The implantation of a phakic, aphakic, or pseudophakic intraocular lens ("intraocular lens", IOL) into a patient's eye is a crucial procedure. The IOL must be adapted as closely as possible to the patient's individual requirements, since any subsequent exchange would involve unnecessary surgical risks. Therefore, even before implantation, it is necessary and desirable to thoroughly investigate the patient's visual acuity through the implanted IOL, i.e., its optical properties, in order to avoid in vivo exchange in any case.

[0003] Traditionally, either computer simulations or optical examination devices into which the IOL to be implanted is inserted are used for this purpose. However, the images created by computer simulations of an eye with average anatomical structure and shown to the patient often only reproduce the general characteristics of the IOL. Therefore, it is impossible to reliably predict the patient's subjective visual impression through the IOL selected for implantation using simulations. Furthermore, it is particularly difficult to reliably simulate various viewing situations, such as different lighting conditions and viewing ranges, such as distance vision when viewing a landscape and near vision when reading a book.

[0004] Optical examination devices are better suited to examining subjective visual impressions in a variety of situations, but to date known examination devices have a very limited field of view and are therefore unable to examine a wide range of the patient's visual angle.

[0005] 1-3 show one such conventional optical examination device 1 with haptics 2 supporting a corneal optic 6 (also called a corneal model optic), a mounting 7 for an IOL 8, and a focusing lens 9 from distal (closer to the observed periphery 3) to proximal (closer to the patient's eye 4) along a central visual axis 5. If rotation of the eye 4 is assumed to tilt the visual axis 5' at a visual angle α (FIG. 2), light rays 10' passing through the device 1, and therefore the perceptible image, are progressively blocked by the iris 11 of the eye 4 (FIG. 3). Furthermore, the remaining actually perceived image has, due to defocus, a contrast and resolution that is significantly different from the contrast and resolution of the IOL 8 in its actually implanted state (hereinafter referred to as the "implanted IOL"), as can be seen from the modulation transfer function ("Modulation Transfer Function", MTL) of the device 1 shown in Figure 4 for visual angles α=0° (dash-dotted line 12), α=2.5° (dashed line 13), and α=5° (dotted line 14) on the one hand, and the nominal MTF of the implanted IOL 8 (solid line 15) on the other hand.

[0006] For all these reasons, it remains difficult for patients to choose an IOL that guarantees an optimal subjective visual impression from the wide variety of IOL versions available, such as monofocal, bifocal, multifocal, EDOF ("extended depth of focus") lenses, light-adjustable lenses (LAL), etc. Summary of the Invention [Problem to be solved by the invention]

[0007] The object of the present invention is to create an apparatus for testing vision through an IOL, which overcomes the drawbacks of the prior art and allows testing of the lens with a wide field of view. [Means for solving the problem]

[0008] This object is achieved by an apparatus of the type mentioned at the beginning, which is characterized according to the invention by the fact that the ocular optics comprises a corrective lens at the distal end and a diverging lens and a converging lens at the proximal end, the corrective lens having a distal concave lens surface and a proximal convex lens surface.

[0009] The combination according to the invention of corrective, diverging and converging lenses in the eyepiece optical system allows, through the special shape of the lens surfaces, the field of view of the device or of the patient's eye looking through the device to be extended, while at the same time blurring and contrast errors in the extended field of view are corrected, ideally eliminated.

[0010] Thus, due to the inventive interaction of the concave-convex correcting lens with the downstream diverging and converging lenses, different vergence and different angular differences are generated for the respective incoming and outgoing light beams with respect to the central visual axis or optical axis for different angles of incidence of the light rays. It is precisely these special vergence or angular differences, in combination with the corneal optics, that allow the incoming light beams from each spatial angle to be essentially directed to the same point on the eye for different visual angles, thereby enabling visual angle correction, i.e., images focused through the IOL that are matched in resolution and contrast to the implanted IOL for different visual angles.

[0011] In a particularly efficient variant, the corneal optics may perform a quick vision test by modeling an average cornea, for example according to the Liou-Brennan Eye Model, or in a particularly precise variant, may model the cornea of ​​an individual patient, for example after prior measurements, allowing for the testing of an IOL that is as realistic as possible for the individual patient.

[0012] In particular, the device according to the invention allows for the testing of subjective visual impressions through an IOL in various situations, whether testing for distance or near vision. The device according to the invention is therefore particularly well suited for testing a wide variety of intraocular lenses, for example, monofocal, bifocal, multifocal, or EDOF lenses. To perform rapid testing of a large number of different intraocular lenses, the haptics may be designed as exchangeable cuvettes in which the IOLs are placed.

[0013] In summary, by utilizing the device according to the present invention, the patient may obtain a realistic subjective visual impression over a wider field of view, even before the IOL is implanted, as if the IOL had been implanted, facilitating the selection of an appropriate IOL.

[0014] In a preferred embodiment, at least one of the opposing lens surfaces of the diverging and converging lenses is aspheric. In the interaction of the aspheric lens with the corneal optics, particularly good visual angle correction, i.e., particularly good focused vision in terms of resolution and contrast, can thus be achieved through the implanted IOL for different visual angles.

[0015] In one advantageous embodiment, at least one of the opposing lens surfaces of the diverging and converging lenses is an aspheric surface of at least fourth order. The use of such an aspheric lens allows optical aberrations such as spherical aberration, astigmatism, etc. to be prevented or corrected. The patient therefore obtains perfect vision over a wide field of view through the IOL, thereby enabling accurate examination. While the use of higher-order aspheric surfaces offers greater flexibility in the design of the ocular optics, lower-order aspheric surfaces are easier to manufacture and their effect on the ray path is easier to predict.

[0016] In a particularly advantageous variant, the fourth order aspheric surface and the sagittal height measured away from the vertex plane of the aspheric surface are selected according to the following formula:

[0017]

number

[0018] Such lens surfaces, whose sagittal height follows a constant function of low order, can be easily and accurately manufactured.

[0019] If the aspheric surface is the distal lens surface of the focusing lens, manufacturing is facilitated and the achievable viewing angle correction for the device may be further improved.

[0020] In particular, to simplify the manufacture of the aspherical surface, it is advantageous if the lens surface of the converging or diverging lens opposite the aspherical surface is flat. To this end, the converging or diverging lens may optionally be made up of a number of individual lenses spaced apart from one another.

[0021] In a preferred variation, at least one of the corneal optics and the ocular optics is provided with an achromatic or superchromatic lens, thereby avoiding chromatic aberration. Lens testing, which matches the resolution, focus, and contrast of the implanted IOL over a wide field of view, can therefore be performed for multiple wavelengths. Furthermore, spherical aberration can be prevented or corrected using the achromatic or superchromatic lens. In this variation, for example, dispersion-free or angle-independent collimation of the light beam passing through the device can be achieved in front of the patient's eye.

[0022] The corneal optic can be designed in various ways: In a variant that is particularly easy to manufacture, the corneal optic comprises a corneal diverging lens and a corneal converging lens, which can be arranged in any order along the optical axis.

[0023] If the converging and diverging lenses of the corneal optics and / or the converging and diverging lenses of the ocular optics have different Abbe numbers, the respective converging and diverging lenses may also form achromatic or superchromatic lenses, correcting or eliminating chromatic aberrations in addition to spherical aberrations. Therefore, by subjecting the IOL to a particularly careful examination, the patient can determine the quality of the IOL, both in terms of visual acuity and color vision, even before its implantation, and thus find a suitable IOL.

[0024] Tests have shown that it is advantageous if the distal lens surface of the corneal focusing lens has at least a fourth-order asphericity. In the interaction of at least one asphericity with the corrective lens of the ocular optics, for example, visual angle corrective lens tests for visual angles of more than 10° can be achieved, allowing the patient to undergo particularly realistic lens examinations over a wide field of view.

[0025] It is particularly advantageous if the sagittal height of the distal lens surface of the corneal focusing lens, measured away from the vertex plane of this distal lens surface, is selected according to the following formula:

[0026]

number

[0027] Such a distal lens surface, whose sagittal height follows a low-order constant function, can be easily and accurately manufactured.

[0028] The corrective lens of the eyepiece optics can also be designed in different ways. In a preferred embodiment, the distal and proximal lens surfaces of the corrective lens are spherical, and the radius of curvature of the distal lens surface of the corrective lens is smaller than the radius of curvature of the proximal lens surface of the corrective lens. With this corrective lens, a significantly expanded field of view can be achieved while avoiding defocus and contrast errors within the expanded field of view due to the interaction between the upstream corneal optics and the downstream diverging or converging lenses of the eyepiece optics.

[0029] In all embodiments, it is advantageous if at least one of the elements, i.e., the corneal optic, the mounting, and the ocular optic, is mounted on a support so as to be movable along the central visual axis. Each of the above elements may be moved as a whole, or if one of the elements comprises a secondary element, such as the above-mentioned corrective lens, converging lens, and diverging lens of the ocular optic, the secondary element may also be movable individually. The adjustable mounting allows for a rapid adaptation of the device to the eye of a patient undergoing a vision test, for example, by moving the optical principal surface of the optic. The convergence of the light rays proximal to the ocular optic can be adapted to the patient's visual deficiency, for example, to correct spherical refractive error. This adaptation can ensure a lens test that simulates the implanted IOL in terms of contrast, resolution, and focusing, even for patients with visual deficiencies.

[0030] It would also be advantageous if at least one of the elements, i.e., the corneal optics, the mounting, and the ocular optics, were movably mounted on a support perpendicular to the central visual axis, thereby allowing the device to be easily adjusted and calibrated.

[0031] This is particularly advantageous when the fitting is designed to accommodate interchangeable intraocular lenses. Such a quick-exchange fitting allows an already tested IOL to be quickly exchanged for a new IOL to be tested within the device. As a result of this quick exchange, patients can efficiently test a number of different IOLs and thus select the IOL that best suits them based on their subjective visual impression for subsequent implantation.

[0032] In a further aspect of the invention, the use of an ocular optical system comprising a corrective lens at its distal end and a diverging lens and a converging lens proximal thereto, the corrective lens having a distal concave lens surface and a proximal convex lens surface, at least one of the opposing lens surfaces of the diverging lens and the converging lens preferably being aspherical, is provided in an apparatus for testing visual acuity through an intraocular lens. Regarding the advantages and possible embodiments of the use of an ocular optical system in an optical testing apparatus, please refer to the comments above regarding the apparatus according to the invention. [Brief explanation of the drawings]

[0033] The invention is explained in more detail below using examples of embodiments shown in the accompanying drawings. [Figure 1] 1 is a schematic side view of a device for testing vision through an intraocular lens according to the prior art, with exemplary light beam paths for an eye viewing the intraocular lens on its central visual axis; [Figure 2] 2 is a schematic side view of the device of FIG. 1, along with an exemplary light beam path for an eye viewing the intraocular lens at a visual angle. [Figure 3] 3 is a schematic side view of the eye of FIG. 2 and the defocused light rays in the light beam path of FIG. 2 that are intercepted by the iris of the eye. [Figure 4] 3 is a contrast diagram showing exemplary modulation transfer functions as achieved by the device of FIGS. 1 and 2 for various viewing angles. [Figure 5] 1 is a schematic side view of an apparatus for testing vision through an intraocular lens according to the present invention, with exemplary light beam paths for an eye viewing the intraocular lens on its central visual axis; [Figure 6] 6 is a schematic side view of the device of FIG. 5, along with an exemplary light beam path of an eye viewing the intraocular lens at a visual angle. [Figure 7] 7 is a schematic side view of the eye of FIG. 6 and the focused light rays in the light beam path of FIG. 6 that are not blocked by the iris of the eye. [Figure 8] 7 is a contrast diagram showing exemplary modulation transfer functions as achieved for various viewing angles by the device of FIGS. 5 and 6. FIG. [Figure 9] FIG. 7 is an exploded side view showing the eyepiece optics of the device of FIGS. 5 and 6. [Figure 10] FIG. 7 is an exploded side view showing the corneal optics of the device of FIGS. 5 and 6. [Figure 11] FIG. 8 is a diagram of longitudinal chromatic aberration versus wavelength showing exemplary chromatic aberrations as they occur in the device of FIGS. 1-3 and in the device of FIGS. 5-7. [Figure 12] FIG. 8 is a diagram of Zernike coefficients versus viewing angle illustrating an exemplary spherical aberration as may occur in the device of FIGS. 1-3 or in the device of FIGS. 5-7. DETAILED DESCRIPTION OF THE INVENTION

[0034] A conventional optical inspection device 1 for an intraocular lens (IOL) 8, as known in the prior art, has already been described above with reference to Figures 1 to 4. Reference numbers in Figures 5 to 12 refer to the same parts as in Figures 1 to 4.

[0035] 5-7 illustrate an inventive optical testing device 16 for testing vision through an IOL 8 before it is implanted in a patient's eye 4. The IOL 8 being tested after implantation (hereinafter referred to as the "implanted IOL") is intended to lead to improved vision for the patient and may be, for example, a monofocal, bifocal, multifocal, EDOF (extended depth of focus) lens, light accommodating lens (LAL), etc.

[0036] To provide the patient with a subjective visual impression of the near, intermediate, or far environment 3 via the pre-implanted IOL 8, the device 16 includes haptics 17, which support the corneal optic 18, a mounting 19 for the IOL 8, and the ocular optic 20 along the central visual axis from distal (closer to the viewing environment 3) to proximal (closer to the patient's eye 4). The haptics 17 may be for any device known in the optical system for mounting optical elements, such as a frame, housing, tube, optical bank, optical table, etc. The haptics 17 may support the optical elements in a fixed position or movably. For example, the corneal optic 18 (or portions thereof), the mounting 19 (or portions thereof), and / or the ocular optic 20 (or portions thereof) may be mounted on the haptics 17 movably along and / or perpendicular to the central visual axis 5 to adjust them relative to one another.

[0037] The optical effect of device 16 is explained below for direct viewing along a central visual axis 5 (FIG. 5) and for oblique direct viewing along a visual axis 5' tilted by a visual angle α (FIG. 6) using two representative light rays 10 (FIG. 5) and 10' (FIG. 6), respectively.

[0038] The light ray 10 or 10' entering from the periphery 3, i.e., from the distal end of the device 16, first passes through the corneal optics 18, which in the illustrated example optically simulates the cornea via a distal diverging lens 21 and a proximal condensing lens 22. In a first variant, the corneal optics 18 models the cornea of ​​an "average patient" according to an eye model, such as the Liou-Brennen eye model. In an alternative variant, the corneal optics 18 simulates the cornea of ​​an individual patient's eye 4, which is measured in advance, for example optically or by ultrasound.

[0039] After the corneal optic 18, the light rays 10 or 10' are directed through the IOL 8 in the mounting 19, which focuses the light rays 10 or 10' according to its refractive power as if it were implanted in the eye 4.

[0040] Mounting device 19 may be any suitable mounting device for mounting IOL 8, for example, a modular rapid-exchange system with a first portion fixedly mounted on support 17 for mounting a rapidly exchangeable second portion, with IOL 8 mounted in or on the second portion, thereby allowing for rapid testing of the IOL by exchanging the second portion. For example, mounting device 19 may include, as a first portion, a clamp-type, plug-in, or magnetic mounting device that houses, as a second portion, an exchangeable cuvette for the IOL, optionally filled with a solution to simulate the interior of the eye.

[0041] The light beam 10 or 10' then passes through the eyepiece optics 20, which includes a distal correcting lens 23 and its proximal diverging and converging lenses 24 and 25. As an alternative to the illustrated embodiment, the converging lens 25 can be positioned distal to the diverging lens 24. The correcting lens 23 has a distal concave lens surface 26 and a proximal convex lens surface 27 (see FIG. 9). Optionally, at least one or both of the opposing lens surfaces 28, 29 of the diverging lens 24 and the converging lens 25 are aspheric (here, the distal lens surface 29 of the converging lens 25).

[0042] Through these special corrective, diverging, and converging lenses 23-25, the light rays 10 and 10' are converged and redirected within the eyepiece optical system 20 based on the visual angle α, so that after passing through the eyepiece optical system 20, they are not blocked by the iris 11 of the eye 4, both in the case of a straight line (FIG. 5, α=0°) and in the case of an inclined visual axis (FIGS. 6 and 7, α≠0°). For a fixed visual angle α, even light rays incident at slightly different angles are naturally not blocked by the iris 11 and are subsequently focused to a peripheral point on the retina of the eye 4.

[0043] 3 and 7, due to the interaction of the corrective, diverging, and converging lenses 23-25 ​​of the ocular optics 20, light ray 10' propagated along the oblique visual axis 5' within device 16 is no longer blocked by the iris 11 of eye 4 and is properly focused onto the retina of eye 4. As a result, the image perceived at visual angles α>0° is not only unblocked but also better matched in contrast and resolution by the implanted IOL 8 than by the conventional device 1, as evidenced by a comparison of the modulation transfer functions of device 1 shown in FIG. 4 with those of device 16 shown in FIG. 8 for α=0° (dash-dotted line 30), α=2.5° (dashed line 31), and α=5° (dotted line 32) for the nominal MTF of the implanted IOL 8 (solid line 15), as shown in the contrast K versus line L diagram. With the device 16 according to the invention, therefore, a wider field of view of the IOL 8 can be examined than with the conventional device 1 .

[0044] In the embodiment of the ocular optical system 20 shown in Figures 5, 6 and 9, the aspheric surface of at least one of the diverging and converging lenses 24, 25 is formed by the distal lens surface 29 of the converging lens 25. In general, an aspheric surface can be described in accordance with DIN ISO 10110 by the sagittal height z measured in the direction away from the vertex plane of the lens surface as a function of the radial distance r to the central visual axis 5 according to the following formula:

[0045]

number

[0046] In the variant of the distal lens surface 29 that is aspheric, this is at least fourth order, i.e., coefficient A of equation (3) for i≧4. iis an aspheric surface where z is at least not equal to 0, and the first summand may or may not be present. In an exemplary subvariation thereof, the sagittal height z1 of the distal lens surface 29 measured away from the vertex plane 33 of the distal lens surface 29 is selected according to the following formula:

[0047]

number

[0048] In an alternative variation of the eyepiece optical system 20, the aspheric surface is formed by the proximal lens surface 28 of the diverging lens 24, which lens surface 28 is an aspheric surface of at least fourth order, and in an exemplary sub-variation thereof, the sagittal height of the distal lens surface measured away from the vertex plane of the proximal lens surface 28 is selected according to the following formula:

[0049]

number

[0050] In the illustrated embodiment, the diverging lens 24 is optionally formed plano-concave, and the converging lens 25 is formed from a first plano-convex section 251 and a second plano-convex section 252. The lens surface 34 opposite the aspherical lens surface 29 is therefore planar; aspherical surfaces are easier to manufacture. Furthermore, as a result of the curvature of the most proximal lens surface (here, the proximal lens surface 35 of the proximal section 252), the light beam 10 or 10' is directed towards the eye 4 in a collimated state.

[0051] In a further optional embodiment, the converging and diverging lenses 24, 25 may have different Abbe numbers, thereby forming an achromatic lens.

[0052] To achieve the visual angle magnification, the concave-convex correcting lens 23 may be designed in many ways, for example, the distal and proximal lens surfaces 26, 27 may each be spherical or aspherical. In the variant shown in Figure 9, the two lens surfaces 26, 27 of the correcting lens 23 are spherical. Furthermore, the distal lens surface 26 has a larger curvature than the proximal lens surface 27, i.e., the radius of curvature of the former is smaller than that of the latter.

[0053] Corneal optic 18 may also be designed in a number of ways. In one embodiment shown in Figures 5, 6, and 10, corneal optic 18 is composed of a (here, plano-concave) corneal diverging lens 21 and a (here, plano-convex) corneal converging lens 22, which may be arranged in either the illustrated order of distal corneal diverging lens 21 and proximal corneal converging lens 22, or in the reverse order of distal corneal diverging lens 21 and proximal corneal diverging lens 22.

[0054] In that variant, the corneal diverging lens 21 and the corneal converging lens 22 have different Abbe numbers to form an achromatic lens, which corrects spherical aberration and optionally chromatic aberration.

[0055] Furthermore, in the illustrated embodiment, the distal lens surface 36 of the corneal focusing lens 22 is aspheric. In one variation, the aspheric surface is of fourth order, and in an exemplary sub-variation thereof, the sagittal height z2 of the distal lens surface 36 measured away from the vertex plane 37 of the distal lens surface 36 is selected according to the following equation:

[0056]

number

[0057] Furthermore, it should be noted that each of lenses 21-25 may be formed both in a unitary state, as shown here in the case of lens 25, and in a multi-section state, i.e., optionally separated from one another.

[0058] In tests, particularly good field expansion was achieved with a vertex curvature ρ of 0.058 / mm to 0.118 / mm, preferably 0.088 / mm, 1×10 -5 / mm to 4.4x10 -5 / mm, preferably 2.7x10 -5 / mm coefficient A2, -0.6x10 ー4 / mm 3 ~-1.6x10 ー4 / mm 3 , preferably -1.1x10 ー4 / mm 3 and a mean apex curvature ρ of 0.01 / mm to 0.09 / mm, preferably 0.05 / mm, a coefficient A2 of 0.005 / mm to 0.025 / mm, preferably 0.015 / mm, a coefficient A3 of -1x10 -5 / mm 3 ~-9x10 -5 / mm 3 , preferably -5x10 -5 / mm 3This could be achieved by an aspheric lens surface 29 having a converging lens 25 with a coefficient A4 of -18 mm to -7 mm, preferably -12.5 mm, and by a corrector lens 23 having a spherical distal lens surface 26 with a radius of curvature of -18 mm to -7 mm, preferably -12.5 mm, and by a spherical proximal lens surface 27 with a radius of curvature of -19 mm to -7 mm, preferably -13 mm.

[0059] 11 and 12 show the longitudinal chromatic aberration (here, focus variation A over wavelength λ) along the central visual axis 5 (FIG. 11) and the Zernike coefficients Z at a wavelength of 546 nm for various viewing angles α. 11 12 shows the improvement achieved in testing for device 16 compared to conventional device 1 with respect to spherical aberration based on the axial displacement (A) of the cornea (Fig. 12). The solid lines with circles 38 and 41 correspond to the results for device 16 according to the invention, the dashed lines with triangles 39 and 42, respectively, correspond to the results for conventional device 1, and the dotted lines with diamonds 40 and 43, respectively, correspond to the results for implanted IOL 8.

[0060] If desired, additional optical elements may be positioned along the central visual axis 5, for example, to correct aberrations or to expand the possible visual angle α for testing the IOL 8. Furthermore, the device 16 may alternatively be designed using wholly or partially non-rotationally symmetric lenses; for example, the aspheric lens surfaces of the corneal optics 18 and / or ocular optics 20 described herein may be replaced by a system including multiple spherical lens surfaces that achieve an equivalent optical effect.

[0061] It goes without saying that, inter alia, two IOLs may be tested simultaneously in binocular (stereoscopic) vision using a setup comprising two parallel devices 16 .

[0062] Very generally, the ocular optics 20 optionally combined with the corneal optics 18 may be used in any device for testing vision through an IOL 8.

[0063] The present invention is not limited to the represented embodiments, but includes all variations, modifications and combinations thereof that fall within the scope of the appended claims.

Claims

1. A device for testing visual acuity through an intraocular lens (8), comprising a corneal optic (18), a mounting device (19) for the intraocular lens (8), and a support (17) for supporting an ocular optic (20) in sequence from distal to proximal to a central visual axis (5); The eyepiece optical system (20) comprises a correcting lens (23) at its distal end, and a diverging lens (24) and a converging lens (25) at its proximal end, The corrective lens (23) comprises a distal concave lens surface (26) and a proximal convex lens surface (27). characterized in that Device.

2. 2. The device according to claim 1, characterized in that at least one of the lens surfaces (28, 29) of the opposing diverging and converging lenses (24, 25) is aspherical.

3. 3. The device according to claim 2, wherein at least one of the lens surfaces (28, 29) of the opposing diverging and converging lenses (24, 25) is an aspheric surface of at least fourth order.

4. The sagittal height (z) measured from the apex plane (33) of the aspherical surface １ ) is selected according to the formula: [Equation 1] where: z １ is the sagittal height measured from distal to proximal, ρ is the vertex curvature, r is the radial distance from the central visual axis (5); A ２ and A ４ is a predetermined coefficient, and when the aspherical surface is the lens surface of the condenser lens (24), A ２ >0, and the aspherical surface is the lens surface of a diverging lens (25), A ２ <0 4. The device according to claim 3, characterized in that

5. 5. The device according to any one of claims 2 to 4, characterized in that the aspheric surface is the distal lens surface (29) of the focusing lens (25).

6. 6. Device according to any one of claims 2 to 5, characterized in that the lens surface (34) of the converging lens or the diverging lens (25, 24) opposite the aspherical surface is flat.

7. 7. The device according to claim 1, wherein at least one of the corneal optics and the ocular optics (18, 20) comprises an achromatic lens (21, 22; 24, 25) or a superachromatic lens.

8. 8. The device according to any one of claims 1 to 7, characterized in that the corneal optics (18) comprises a corneal diverging lens (21) and a corneal converging lens (22).

9. 9. The device according to claim 7, wherein the corneal diverging lens (21) and the corneal converging lens (22) have different Abbe numbers, and / or the converging lens and the diverging lens (24, 25) of the eyepiece optical system (20) have different Abbe numbers.

10. 10. The device of claim 9, wherein the distal lens surface (36) of the corneal focusing lens (22) is aspheric to at least fourth order.

11. The sagittal height (z) of the distal lens surface (36) of the corneal focusing lens (22) measured away from the apex plane (37) of the distal lens surface ２ ) is selected according to the formula: [Equation 2] where: z ２ is the sagittal height measured from distal to proximal, ρ is the vertex curvature, r is the radial distance from the central visual axis (5); A ２ and A ４ is the default coefficient 11. The device according to claim 10, characterized in that

12. 12. The device according to claim 1, wherein the distal lens surface and the proximal lens surface (26, 27) of the corrective lens (23) are spherical, and the radius of curvature of the distal lens surface (26) of the corrective lens (23) is smaller in size than the radius of curvature of the proximal lens surface (27) of the corrective lens (23).

13. 13. The device according to claim 1, wherein at least one of the elements, i.e. the corneal optics (18), the mounting (19) and the ocular optics (20), is mounted on the support (17) so as to be movable along the central visual axis (5) and / or perpendicular to the central visual axis (5).

14. 14. The device according to any one of claims 1 to 13, characterized in that the mounting (19) is designed to accommodate the intraocular lens (8) in an exchangeable manner.

15. 1. Use of an ocular optical system (20) comprising a corrective lens (23) at its distal end and a diverging lens (24) and a converging lens (25) proximal thereto, the corrective lens (23) comprising a distal concave lens surface (26) and a proximal convex lens surface (27), and at least one of the lens surfaces (28, 29) of the opposing diverging and converging lenses (24, 25) is preferably aspherical, in a device (16) for testing visual acuity through an intraocular lens (8).

Images