Optical lens group and vision detection device

Abstract

The utility model relates to an optical lens group and a vision detection device.The optical lens group is applied to the vision detection device.The optical lens group comprises a display screen, a first lens group and a second lens group, the display screen is used for displaying vision detection icons, the first lens group directly faces the display screen, the first lens group has positive diopter, and the second lens group has negative diopter; the second lens group has negative diopter, and the second lens group is arranged between the first lens group and the display screen. According to the optical lens group provided by the invention, the optical lens group has good imaging quality and good detail resolution capability, the correction of chromatic aberration and distortion can be realized, and the influence on vision examination is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vision detection, and in particular to an optical lens group and a vision detection device. BACKGROUND

[0002] Traditional vision examination needs the assistance of optometrists, and the optometrists determine the vision of the examinee through dialogue feedback with the examinee.

[0003] In order to improve the intelligent degree of vision examination, a vision detection device appears in the related art, and an optical lens is one of the main structures of the vision detection device. However, the optical lens in the related art has problems such as distortion, which can easily affect the vision examination. UTILITY MODEL CONTENT

[0004] The present application provides an optical lens group and a vision detection device, so that the optical lens group has good imaging quality and good detail resolution capability, and can correct chromatic aberration and distortion to at least partially solve the above technical problems.

[0005] In order to achieve the above purpose, according to the first aspect of the present application, an optical lens group is provided, which is applied to a vision detection device, and the optical lens group comprises:

[0006] A display screen is configured to display a vision detection icon.

[0007] A first lens group is configured to be positive to the display screen, and the first lens group has a positive refractive power.

[0008] A second lens group has a negative refractive power, and the second lens group is arranged between the first lens group and the display screen.

[0009] Optionally, the center points of the first lens group, the second lens group and the display screen are located on the same straight line.

[0010] Optionally, the first lens group comprises a first lens and a second lens, the second lens is positive to the second lens group, and the first lens is attached to a side of the second lens which is opposite to the second lens group.

[0011] Optionally, the optical lens group further comprises a first adhesive layer, and the first adhesive layer is configured to connect the first lens and the second lens, wherein

[0012] The side of the first lens facing the second lens is provided with the first adhesive layer; and / or

[0013] The side of the second lens facing away from the second lens group is provided with the first adhesive layer.

[0014] Optionally, the second lens group comprises a third lens and a fourth lens, the third lens is positive to the first lens group, and the fourth lens is attached to a side of the third lens opposite to the first lens group.

[0015] Optionally, the optical lens group further comprises a second adhesive layer for connecting the third lens and the fourth lens, wherein,

[0016] the side of the third lens away from the first lens group is provided with the second adhesive layer; and / or,

[0017] the side of the fourth lens facing the third lens is provided with the second adhesive layer.

[0018] Optionally, the distance between the first lens group and the display screen is less than 200 mm.

[0019] Optionally, the number of pixels corresponding to each degree of view angle of the optical lens group is PPD, wherein 364≤PPD≤378 or 458≤PPD≤477.

[0020] According to a second aspect of the present application, a visual acuity detection device is provided, comprising the optical lens group as described above.

[0021] Optionally, the visual acuity detection device comprises a housing, the housing is formed with a mounting cavity, the housing is formed with a visual acuity examination window, the visual acuity examination window is opposite to the mounting cavity, the optical lens group is arranged in the mounting cavity, and the distance between the visual acuity examination window and the first lens group is between 10 mm and 30 mm.

[0022] In the optical lens group of the embodiments of the present application, the user can observe the visual acuity detection icon from the side of the first lens group away from the second lens group, the light of the display screen is transmitted to the user's eye after passing through the second lens group and the first lens group, and the imaging of the visual acuity detection icon through the first lens group and the second lens group makes the distance of the user watching the visual acuity detection icon meet the detection requirements. At the same time, the first lens group has positive refractive power, and the second lens group has negative refractive power, so that the optical lens group has good imaging quality and good detail resolution capability, and can correct chromatic aberration and distortion to avoid affecting the visual acuity examination.

[0023] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description only show some embodiments of the present application, and all other drawings obtained by those skilled in the art without creative effort based on these drawings also belong to the protection scope of the present application.

[0025] In order to more completely understand the present application and its beneficial effects, the following will be described in conjunction with the drawings, wherein the same reference numerals in the following description represent the same parts.

[0026] Figure 1 is one of the structural schematic diagrams of the optical lens set provided in the exemplary embodiments of the present disclosure;

[0027] Figure 2 is the second structural schematic diagram of the optical lens set provided in the exemplary embodiments of the present disclosure;

[0028] Figure 3 is the MTF curve diagram of the optical lens set of Example 1 of the present disclosure;

[0029] Figure 4 is the axial chromatic aberration diagram of the optical lens set of Example 1 of the present disclosure;

[0030] Figure 5 is the f~th(θ) distortion diagram of the optical lens set of Example 1 of the present disclosure;

[0031] Figure 6 is the MTF curve diagram of the optical lens set of Example 2 of the present disclosure;

[0032] Figure 7 is the axial chromatic aberration diagram of the optical lens set of Example 2 of the present disclosure;

[0033] Figure 8 is the f~th(θ) distortion diagram of the optical lens set of Example 2 of the present disclosure.

[0034] Explanation of reference numerals:

[0035] 1, display screen; 2, first lens set; 3, second lens set; 21, first lens; 22, second lens; 31, third lens; 32, fourth lens. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort also belong to the protection scope of the present application.

[0037] According to a first aspect of the present application, referring to Figure 1 and Figure 2 , the present disclosure provides an optical lens group. The optical lens group is applied to a vision detection device, and the optical lens group comprises a display screen 1, a first lens group 2 and a second lens group 3. The display screen 1 is used to display a vision detection icon. The first lens group 2 is opposite to the display screen 1. The first lens group 2 has a positive refractive power. The second lens group 3 has a negative refractive power. The second lens group 3 is arranged between the first lens group 2 and the display screen 1.

[0038] According to the optical lens group of the embodiments of the present application, a user can observe the vision detection icon from a side of the first lens group 2 away from the second lens group 3. The light of the display screen 1 is transmitted to the user's eye after passing through the second lens group 3 and the first lens group 2. The imaging of the vision detection icon through the first lens group 2 and the second lens group 3 makes the distance of the user watching the vision detection icon meet the detection requirements. At the same time, the first lens group 2 has a positive refractive power, and the second lens group 3 has a negative refractive power, so that the optical lens group has good imaging quality and good detail resolution capability, and can correct chromatic aberration and distortion to avoid affecting the vision examination.

[0039] It can be understood that the display screen 1 can switch the size of the displayed vision detection icon to realize the strength examination of the user.

[0040] In some embodiments, the center points of the first lens group 2, the second lens group 3 and the display screen 1 are located on the same straight line.

[0041] It can be understood that the first lens group 2, the second lens group 3 and the display screen 1 are arranged side by side, and the central axes of the first lens group 2, the second lens group 3 and the display screen 1 coincide, so that the light of the display screen 1, i.e. the light of the vision detection icon, can be better transmitted to the first lens group 2 and the second lens group 3, so that the first lens group 2 and the second lens group 3 can image the vision detection icon, so that the user can use the optical lens group to examine the vision.

[0042] It can be understood that the first lens group 2, the second lens group 3 and the display screen 1 are center-symmetric structures, and the physical center of the first lens group 2, the second lens group 3 and the display screen 1 is also the optical center.

[0043] In some embodiments, referring to Figure 1 and Figure 2 , the first lens group 2 comprises a first lens 21 and a second lens 22. The second lens 22 is opposite to the second lens group 3. The first lens 21 is attached to a side of the second lens 22 away from the second lens group 3.

[0044] It can be understood that the first lens 21 and the second lens 22 are connected to form the first lens group 2, and the first lens 21 and the second lens 22 can perform imaging processing on the image transmitted by the second lens group 3, so that the user can use the optical lens group to perform vision examination.

[0045] It can be understood that the first lens 21 and the second lens 22 are connected by pasting, which is simple and convenient.

[0046] In some embodiments, the optical lens group further comprises a first adhesive layer for connecting the first lens 21 and the second lens 22, wherein the first lens 21 is provided with the first adhesive layer on the side facing the second lens 22.

[0047] It can be understood that by providing the first adhesive layer on the side of the first lens 21 facing the second lens 22, i.e. on the wall surface where the first lens 21 and the second lens 22 are connected, the first lens 21 and the second lens 22 can be connected together through the first adhesive layer, which is simple and convenient.

[0048] In some embodiments, the optical lens group further comprises a first adhesive layer for connecting the first lens 21 and the second lens 22, wherein the second lens 22 is provided with the first adhesive layer on the side away from the second lens group 3.

[0049] It can be understood that by providing the second adhesive layer on the side of the second lens 22 facing the first lens 21, i.e. on the wall surface where the second lens 22 and the first lens 21 are connected, the first lens 21 and the second lens 22 can be connected together through the second adhesive layer, which is simple and convenient.

[0050] In some embodiments, referring to Figure 1 and Figure 2 , the second lens group 3 comprises a third lens 31 and a fourth lens 32, the third lens 31 is opposite to the first lens group 2, and the fourth lens 32 is attached to the side of the third lens 31 away from the first lens group 2.

[0051] It can be understood that the third lens 31 and the fourth lens 32 are connected to form the third lens group 31, and the third lens 31 and the fourth lens 32 can perform imaging processing on the image transmitted by the fourth lens group 32, so that the user can use the optical lens group to perform vision examination.

[0052] It can be understood that the third lens 31 and the fourth lens 32 are connected by pasting, which is simple and convenient.

[0053] In some embodiments, the optical lens group further comprises a second adhesive layer for connecting the third lens 31 and the fourth lens 32, wherein the third lens 31 is provided with the second adhesive layer on the side away from the first lens group 2.

[0054] It can be understood that by arranging the second adhesive layer on the side of the third lens 31 facing the fourth lens 32, i.e. at the wall surface where the third lens 31 is connected to the fourth lens 32, the third lens 31 and the fourth lens 32 can be connected together through the second adhesive layer, which is simple and convenient.

[0055] In some embodiments, the fourth lens 32 is provided with a second adhesive layer on the side facing the third lens 31.

[0056] It can be understood that by arranging the second adhesive layer on the side of the fourth lens 32 facing the third lens 31, i.e. at the wall surface where the fourth lens 32 is connected to the third lens 31, the third lens 31 and the fourth lens 32 can be connected together through the second adhesive layer, which is simple and convenient.

[0057] In some embodiments, the distance between the first lens group 2 and the display screen 1 is less than 200 mm.

[0058] It can be understood that when the distance between the first lens group 2 and the display screen 1 is greater than 200 mm, the size of the optical lens group may be too large, which is not conducive to the miniaturization of the vision detection device provided with the optical lens group. Therefore, the distance between the first lens group 2 and the display screen 1 is set to be less than 200 mm in the present application, which is conducive to the miniaturization of the optical lens group and the vision detection device provided with the optical lens group while ensuring the imaging effect.

[0059] In some embodiments, the number of pixels corresponding to each degree of view angle of the optical lens group is PPD, wherein 364≤PPD≤378 or 458≤PPD≤477.

[0060] It can be understood that since the number of pixels of each stroke of the vision detection icon is PPD*view angle / 60, setting the number of pixels corresponding to each degree of view angle of the optical lens group to be between 364 and 378 or between 458 and 477 can make the visual acuity corresponding to the visual angle of the optical lens group within the allowable range, thereby ensuring the performance of the optical lens group.

[0061] Specifically, referring to the following table of correspondence between visual acuity and view angle, the table shows the correspondence between visual acuity and view angle and the corresponding allowable range.

[0062]

[0063] Taking the "E" vision detection icon as an example, the number of pixels of each stroke of "E" is PPD*α / 60. In order to meet the requirements in the "E" vision detection icon, the number of pixels corresponding to each degree of view angle of the optical lens group needs to be set to be between 364 and 378 or between 458 and 477. Figure 8 ​

[0064] According to a second aspect of the present application, the present disclosure provides a visual acuity detection device. The visual acuity detection device comprises the optical lens group described above.

[0065] According to the visual acuity detection device of the embodiments of the present application, the user can observe the visual acuity detection icon from the side of the first lens group 2 away from the second lens group 3, and the light of the display screen 1 is transmitted to the user's eye after passing through the second lens group 3 and the first lens group 2, and the imaging of the visual acuity detection icon through the first lens group 2 and the second lens group 3 makes the distance of the user watching the visual acuity detection icon meet the detection requirements. At the same time, the first lens group 2 has a positive refractive power, and the second lens group 3 has a negative refractive power, so that the optical lens group has good imaging quality and good detail resolution capability, and can correct chromatic aberration and distortion, avoiding affecting the visual acuity examination.

[0066] In some embodiments, the visual acuity detection device comprises a housing, the housing is formed with a mounting cavity, the housing is formed with a visual acuity examination window, the visual acuity examination window is opposite to the mounting cavity, the optical lens group is arranged in the mounting cavity, and the distance between the visual acuity examination window and the first lens group 2 is between 10mm and 30mm.

[0067] It can be understood that the user observes the visual acuity detection icon through the visual acuity examination window, that is, the distance between the visual acuity examination window and the first lens group 2, that is, the distance between the eye and the first lens group 2. Therefore, when the distance between the visual acuity examination window and the first lens group 2 is less than 10mm, it is not conducive for the user to observe the visual acuity detection icon, and when the distance between the visual acuity examination window and the first lens group 2 is greater than 30mm, it will cause the size of the optical lens group to be too large, which is not conducive to the miniaturization of the visual acuity detection device. Therefore, the present application sets the distance between the visual acuity examination window and the first lens group 2 to be between 10mm and 30mm, which not only ensures the visual acuity examination effect of the user, but also is conducive to the miniaturization of the visual acuity detection device.

[0068] In Example One, the distance between the visual acuity examination window and the first lens group 2 is preferably 15mm, the distance between the first lens group 2 and the display screen 1 is preferably 98.14mm, and the number of pixels corresponding to each degree of view angle of the optical lens group is PPD, which is preferably 370.

[0069] The spherical surface of the first lens 21 facing away from the second lens 22 is S1, the spherical surface of the first lens 21 facing towards the second lens 22 is S2, the spherical surface of the second lens 22 facing towards the first lens 21 is S3, the spherical surface of the second lens 22 facing away from the first lens 21 is S4, the spherical surface of the third lens 31 facing away from the fourth lens 32 is S5, the spherical surface of the third lens 31 facing towards the fourth lens 32 is S6, the spherical surface of the fourth lens 32 facing towards the third lens 31 is S7, and the spherical surface of the fourth lens 32 facing away from the third lens 31 is S8. Referring to the design value table of the optical lens group below, the table introduces the curvature radius, the interval D / thickness, the refractive index, and the Abbe number of each surface.

[0070]

[0071] Figure 3 The optical lens MTF (Modulation Transfer Function) curve of Example 1 is shown in the figure, which represents the lens imaging modulation degree of different spatial frequencies under each field of view. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF in the full field of view is above 0.3, and in the range of 0-30 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0072] Figure 4 The optical lens MTF (Modulation Transfer Function) curve of Example 1 is shown in the figure, which represents the lens imaging modulation degree of different spatial frequencies under each field of view. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF in the full field of view is above 0.3, and in the range of 0-30 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0073] Figure 5 The f ~ tan(θ) distortion curve of Example 1 is shown in the figure, which represents the f ~ tan(θ) distortion at different image heights on the imaging surface. The horizontal axis represents the f ~ tan(θ) distortion value (unit: %), and the vertical axis represents the field of view angle (unit: °). As can be seen from the figure, the f ~ tan(θ) distortion of the lens of Example 1 is controlled within ±0.3%, which shows that the distortion of the optical lens is well corrected.

[0074] In Example 2, the distance between the vision examination window and the first lens group 2 is preferably 15 mm, the distance between the first lens group 2 and the display screen 1 is preferably 175.18 mm, and the number of pixels per degree of view angle of the optical lens group is PPD, which is preferably 470.

[0075] The spherical surface of the first lens 21 facing away from the second lens 22 is S1, the spherical surface of the first lens 21 facing towards the second lens 22 is S2, the spherical surface of the second lens 22 facing towards the first lens 21 is S3, the spherical surface of the second lens 22 facing away from the first lens 21 is S4, the spherical surface of the third lens 31 facing away from the fourth lens 32 is S5, the spherical surface of the third lens 31 facing towards the fourth lens 32 is S6, the spherical surface of the fourth lens 32 facing towards the third lens 31 is S7, and the spherical surface of the fourth lens 32 facing away from the third lens 31 is S8. Referring to the design value table of the optical lens assembly below, the table introduces the curvature radius, interval D / thickness, refractive index, and Abbe number of each surface.

[0076]

[0077] Figure 6 The optical lens MTF (Modulation Transfer Function) curve diagram of Example Two represents the lens imaging modulation degree of different spatial frequencies under each field of view. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the diagram, the MTF in the full field of view is above 0.15, and in the range of 0-30 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0078] Figure 7 The optical lens MTF (Modulation Transfer Function) curve diagram of Example Two represents the lens imaging modulation degree of different spatial frequencies under each field of view. The horizontal axis represents the spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the diagram, the MTF in the full field of view is above 0.15, and in the range of 0-30 lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0079] Figure 8 The f ~ tan(θ) distortion curve diagram of Example Two represents the f ~ tan(θ) distortion at different image heights on the imaging surface. The horizontal axis represents the f ~ tan(θ) distortion value (unit: %), and the vertical axis represents the field of view angle (unit: °). As can be seen from the diagram, the f ~ tan(θ) distortion of the lens of Example Two is controlled within ±0.04%, indicating that the distortion of the optical lens is well corrected.

[0080] In the description of the present application, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0081] In the above embodiments, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0082] The embodiments, implementation manners and related technical features of the present application can be combined or replaced with each other without conflict.

[0083] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification made to the above embodiment without departing from the technical solution content of the present application and in accordance with the technical essence of the present application still belongs to the scope of the technical solution of the present application.

Claims

1. An optical lens assembly, characterized in that, The optical lens assembly, used in a vision testing device, includes: A display screen for showing vision test icons; A first lens group is positioned opposite the display screen, and the first lens group has positive diopter. The second lens group has negative refractive power and is disposed between the first lens group and the display screen.

2. The optical lens assembly according to claim 1, characterized in that, The center points of the first lens group, the second lens group, and the display screen are located on the same straight line.

3. The optical lens assembly according to claim 1, characterized in that, The first lens group includes a first lens and a second lens, with the second lens facing the second lens group and the first lens attached to the side of the second lens that is opposite to the second lens group.

4. The optical lens assembly according to claim 3, characterized in that, The optical lens assembly further includes a first adhesive layer for connecting the first lens and the second lens, wherein... The first adhesive layer is provided on the side of the first lens facing the second lens; and / or, The first adhesive layer is provided on the side of the second lens opposite to the second lens group.

5. The optical lens assembly according to claim 1, characterized in that, The second lens group includes a third lens and a fourth lens. The third lens is directly opposite the first lens group, and the fourth lens is attached to the side of the third lens that is opposite to the first lens group.

6. The optical lens assembly according to claim 5, characterized in that, The optical lens assembly further includes a second adhesive layer for connecting the third lens and the fourth lens, wherein... The third lens has a second adhesive layer on the side opposite to the first lens group; and / or The fourth lens has a second adhesive layer on the side facing the third lens.

7. The optical lens assembly according to any one of claims 1 to 6, characterized in that, The distance between the first lens group and the display screen is less than 200mm.

8. The optical lens assembly according to any one of claims 1 to 6, characterized in that, The number of pixels per degree of field of view of the optical lens group is PPD, wherein 364≤PPD≤378 or 458≤PPD≤477.

9. A vision testing device, characterized in that, Includes the optical lens assembly as described in any one of claims 1 to 8.

10. The vision testing device according to claim 9, characterized in that, The vision testing device includes a housing with a mounting cavity and a vision testing window facing the mounting cavity. The optical lens assembly is disposed within the mounting cavity, and the distance between the vision testing window and the first lens assembly is between 10mm and 30mm.

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