JP2018169483A - Objective optical system for microscope and microscope using the same - Google Patents

Abstract

To provide an objective optical system for a microscope capable of obtaining a clear observation image regardless of a type of sample or sample placement method or the like even if the sample is disposed in contact with or next to a face closest to an object side of the optical system.SOLUTION: A sample is disposed in contact with or next to a face closest to an object side of an objective lens group 11. A lens component included in the face closest to the object side of the objective lens group 11 is made from an optical material with a Knoop hardness of 1500 or more.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a microscope that captures an image of a sample to be observed by a camera function provided in a portable information terminal and displays a photographed image on a display of the portable information terminal, and an objective optical system for a microscope used therefor.

  The applicant of the present invention uses a portable information terminal installation type microscope that takes an image of a sample to be observed by a camera function provided in a portable information terminal such as a smartphone or a tablet, and displays the photographed image on the display of the portable information terminal. It has been proposed (see Japanese Patent Application No. 2016-163997).

  Further, as an optical system that can be used in Patent Document 1, an optical system in which a sample to be observed is directly placed on the most object-side surface of the optical system is known (see, for example, Patent Document 1).

US Pat. No. 7,995,272

  However, in the optical system described in Patent Document 1, when a sample with high hardness or the like is placed, or when the tip of tweezers for gripping the sample is touched, the optical system that is the placement surface of the sample There is a risk that the surface on the most object side will be damaged. Therefore, when the optical system described in Patent Document 1 is adopted in the above-mentioned microscope proposed by the present applicant, there is a possibility that a clear observation image cannot be obtained due to the influence of the wound thus made. .

  The present invention has been made in view of the above points, and even when the sample is disposed so as to be in contact with or adjacent to the most object-side surface of the optical system, the type of the sample or the placement of the sample It is an object to provide a microscope objective optical system capable of obtaining a clear observation image and a microscope using the same regardless of the method.

In order to achieve the above object, the microscope objective optical system of the present invention comprises:
An objective optical system for a microscope used for a microscope that captures an image of a sample to be observed by a camera function provided in a portable information terminal and displays a photographed image on a display of the portable information terminal,
The specimen is placed in contact with or adjacent to the most object-side surface,
The lens component constituting the most object side surface is formed of an optical material having a Knoop hardness of 1500 or more.

  Here, the “lens component” refers to a single lens or a cemented lens.

  For example, plaque and tartar are collected to observe bacteria in the oral cavity, and plaque and tartar are collected when the plaque and tartar are placed directly on the most object side surface of the objective lens group. When the collected dental plaque and calculus are placed by the dental scaler (made of stainless steel) used for the purpose, there is a possibility that the surface closest to the object side of the objective lens group may be damaged.

  In order to observe soil microorganisms outdoors, when placing an aqueous solution containing soil components directly on the surface closest to the object side of the objective lens group, when wiping the aqueous solution with the soil components, The surface of the objective lens group closest to the object side may be scratched.

  Therefore, in the optical system of the present invention, the lens component constituting the most object-side surface is formed of an optical material having a Knoop hardness of 1500 or more. As a result, the surface closest to the object has sufficient hardness, so even if the sample is placed directly on the surface itself or the sample is wiped off the surface, the surface will be scratched. Hateful.

  Here, if the Knoop hardness is a value less than 1500, it may be caused by minerals mixed in the sample, fine stone fragments, scratches caused by glassy crystals, etc., cloth for wiping the mounting surface, glass fibers adhering to paper, etc. Scratches that occur cannot be prevented sufficiently.

  Therefore, according to the objective optical system for a microscope of the present invention, the surface on the most object side of the optical system which is the sample mounting surface is hardly scratched and is not affected by the scratch. A clear observation image can be obtained regardless of the sample placement method or the like.

In order to achieve the above object, the objective optical system for a microscope of the present invention is
An objective optical system for a microscope used for a microscope that captures an image of a sample to be observed by a camera function provided in a portable information terminal and displays a photographed image on a display of the portable information terminal,
The specimen is placed in contact with or adjacent to the most object-side surface,
The lens component constituting the most object side surface is formed of sapphire.

  Of optical materials having a Knoop hardness of 1500 or more, sapphire has a relatively high workability. For example, when forming a very small mounting surface of about φ5 mm, sapphire is easy to manufacture. In addition, since sapphire has a relatively high refractive index of about 1.75, the use of sapphire makes it possible to reduce the lens component that forms the most object-side surface of the objective lens group, thereby miniaturizing the entire optical system. It becomes easy.

In order to achieve the above object, the microscope of the present invention is
A microscope provided with any one of the above objective optical systems for a microscope,
A microscope main body, and a mounting table connected to the microscope main body on which the portable information terminal is mounted;
The microscope main body has a sample placement unit for placing the sample,
The objective lens group of the objective optical system for a microscope is arranged inside the microscope main body so that the most object side surface of the objective lens group is exposed at the sample mounting portion. .

It is a perspective view which shows the microscope which concerns on 1st Embodiment, FIG. 1A shows the state which has mounted the portable information terminal, and FIG. 1B shows the state which has not mounted the portable information terminal. II-II sectional view taken on the line which shows the internal structure of the microscope of FIG. Sectional drawing which follows the optical axis which shows the structure of the objective optical system for microscopes of the microscope of FIG. Sectional drawing which follows the optical axis which shows the structure of the objective lens group of the objective optical system for microscopes of FIG. FIG. 4 is a cross-sectional view along the optical axis showing the configuration of a first imaging lens group of the microscope objective optical system in FIG. 3. FIG. 4 is a cross-sectional view along the optical axis showing the configuration of a second imaging lens group of the microscope objective optical system in FIG. 3. FIG. 3A is an aberration curve diagram of the microscope objective optical system of FIG. 3, FIG. 3A shows spherical aberration, FIG. 3B shows astigmatism, and FIG. 3C shows distortion. Sectional drawing which follows the optical axis which shows the structure of the objective optical system for microscopes of the microscope which concerns on 2nd Embodiment. Sectional drawing which follows the optical axis which shows the structure of the objective lens group of the objective optical system for microscopes of FIG. FIG. 9 is a cross-sectional view along the optical axis showing the configuration of the first imaging lens group of the microscope objective optical system in FIG. 8. FIG. 11 is an aberration curve diagram of the microscope objective optical system of FIG. 8, in which FIG. 11 shows spherical aberration, FIG. 11 shows astigmatism, and FIG. 11 shows distortion. The photograph which shows the observation image of colon_bacillus | E._coli with the microscope of FIG. 1 or FIG. The photograph which shows the observation image of Salmonella by the microscope of FIG. 1 or FIG. The photograph which shows the observation image of S. aureus by the microscope of FIG. 1 or FIG. The photograph which shows the observation image of Pseudomonas aeruginosa by the microscope of FIG. 1 or FIG. The photograph which shows the observation image of the black mold spore by the microscope of FIG. 1 or FIG. The photograph which shows the observation image of yeast (Candida) by the microscope of FIG. 1 or FIG. The photograph which shows the observation image of the wine yeast by the microscope of FIG. 1 or FIG. The photograph which shows the observation image of the bacteria in the oral cavity by the microscope of FIG. 1 or FIG.

[First Embodiment]
Hereinafter, the microscope M according to the first embodiment and the optical system used therefor will be described with reference to FIGS. The microscope M captures an image of a sample to be observed by a camera function provided in the portable information terminal P and displays it on a display.

  First, the configuration of the microscope M will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1A, the microscope M includes a microscope main body 1, a mounting table 2 that can be detachably connected to the microscope main body 1, and a portable information terminal P mounted on the mounting table 2.

  As shown in FIGS. 1B and 2, the microscope main body 1 includes a housing 1 a in which a recessed portion that is recessed in the horizontal direction is formed, a sample mounting portion 1 b that is provided below the recessed portion of the housing 1 a, and a housing. The light source 1c is disposed above the concave portion of the body 1a, and irradiates the sample mounting portion 1b with light, and the optical system 1d (objective optical system for microscope) is disposed inside the housing 1a. .

  The mounting table 2 is configured as an inverted L-shaped member by a plate-shaped mounting plate 2a on which the portable information terminal P is mounted and a plate-shaped support leg 2b that supports the mounting plate 2a. A circular see-through window 2c is formed in the mounting plate 2a so as to penetrate from the surface on the side where the portable information terminal P is mounted to the surface on the microscope body 1 side. The see-through window 2c is formed at a position that coincides with the camera lens P1 (second imaging lens group) of the portable information terminal mounted on the mounting table 2.

  Among the lens groups constituting the optical system 1d, an objective lens group 1d1 and a first imaging lens group 1d2 are arranged inside the housing 1a. A mirror m is arranged between the objective lens group 1d1 and the first imaging lens group 1d2.

  The objective lens group 1d1 is arranged so that the surface closest to the object is exposed on the sample mounting portion 1b, and the sample to be observed is adjacent to the surface directly or through a cover glass or the like. Placed.

  The light irradiated from the light source 1c and transmitted through the sample passes through the objective lens group 1d1, is reflected by the mirror m, and passes through the first imaging lens group 1d2, and then the housing 1a (that is, the microscope body 1). The light is emitted to the outside (specifically, a position corresponding to the see-through window 2c of the mounting table 2).

  The light emitted to the outside of the housing 1a is imaged by the camera lens P1 of the portable information terminal P mounted on the mounting table 2 (that is, the second imaging optical system that moves during focusing). The image (that is, the observation image of the sample) is photographed by an imaging element built in the portable information terminal P and displayed as a photographed image on the display of the portable information terminal P.

  Next, the configuration of the optical system 1d will be described in detail with reference to FIGS. In the cross-sectional views along the optical axis of each lens group shown in FIGS. 4 to 6, the numbers r1, r2,... And d1, d2,. It corresponds to. In numerical data to be described later, s represents a surface number, r represents a radius of curvature of each surface, d represents a surface spacing, nd represents a refractive index in the d line, and νd represents an Abbe number in the d line.

  As shown in FIG. 3, the optical system 1d includes an objective lens group G11 (that is, the objective lens group 1d1) and a first imaging lens group G12 (that is, the first lens group) arranged in order from the object side on the optical axis Lc. 1 imaging lens group 1d2) and second imaging lens group G13 (that is, camera lens P1).

  An image of the sample to be observed (an image located on the object plane O) is formed once on the first image plane IM1 by the objective lens group G11. The image formed on the first image plane IM1 is formed again on the second image plane IM2 by the first imaging lens group G12 and the second imaging lens group G13. The second image plane IM2 coincides with the imaging plane of the imaging element of the portable information terminal P, and the image formed on the plane is displayed on the display of the portable information terminal P.

  As shown in FIG. 4, the objective lens group G11 includes, in order from the object side, a lens L11 that is a flat lens, a lens L12 that is a planoconvex lens having a positive refractive power and a convex surface facing the image side, and a negative lens. A lens L13 that is a meniscus lens having a refractive power and having a concave surface facing the image side, a lens L14 that is a biconvex lens having a positive refractive power, and a meniscus lens having a negative refractive power and having a concave surface facing the image side And a lens L15.

  In the objective lens group G11, the lens L13 and the lens L14 are cemented.

  Here, the lens component (lens L11) constituting the most object side surface of the objective lens group G11 is formed of an optical material (specifically, sapphire) having a Knoop hardness of 1500 or more. As a result, the most object-side surface has sufficient hardness, so even if the sample is directly placed on the surface itself, the surface is hardly damaged. In the optical system 1d, since it is not affected by the scratches thus formed, a clear observation image can be obtained regardless of the type of sample or the method of placing the sample.

  The surface data relating to the objective lens group G11 is shown below.

  As shown in FIG. 5, the first imaging lens group G12 includes a lens L21, which is a biconvex lens having a positive refractive power, and a lens L22, which is a meniscus lens having a negative refractive power and having a convex surface facing the image side. And a lens L23 which is a plano-convex lens having a positive refractive power and having a flat surface facing the image side, and a lens L24 which is a flat lens.

  In the first imaging lens group G12, the lens L21 and the lens L22 are cemented.

  The surface data relating to the first imaging lens group G12 is shown below.

  As shown in the numerical data 2 above, a flat lens is located closest to the image side of the first imaging lens group G12 (that is, between the first imaging lens group G12 and the second imaging lens group G13). A certain lens L24 is arranged. The lens L24 is fixed during focusing. Thereby, in the optical system 1d, the first imaging lens group G12 and the second imaging lens group G13 are configured to be separable as independent optical systems.

  However, the lens L24 is not limited to a flat lens, and may be a spherical or aspherical lens based on the shape of the housing 1a (placement space of the first imaging lens group G12), required optical performance, and the like. May be used.

  As shown in FIG. 6, the second imaging lens group G13 has a positive refractive power, a lens L31 which is a biconvex lens having a positive refractive power, a lens L32 which is a biconcave lens having a negative refractive power, and the like. The lens L33 is a meniscus lens having a convex surface facing the image side.

  In the optical system 1d, focusing is performed by moving the entire second imaging lens group G13 along the optical axis Lc. Specifically, focusing is performed by changing a surface interval (6.60 mm) related to surface number 6 in numerical data 3 described later. The focusing method is not limited to such a configuration, and may be performed by moving a part of the second imaging lens group along the optical axis.

  The surface data relating to the second imaging lens group G13 is shown below.

  FIG. 7 shows aberration diagrams related to the entire optical system 1d. In FIG. 7, FIG. 7A shows spherical aberration (SA (mm)), FIG. 7B shows astigmatism (AST (mm)), and FIG. 7C shows distortion aberration (DIS (%)). In FIG. 7A (spherical aberration), the solid line indicates the F line, the broken line indicates the d line, and the alternate long and short dash line indicates the C line. In FIG. 7B (astigmatism), a solid line indicates a tangential plane, and a broken line indicates a sagittal plane.

  As is apparent from the aberration diagram of FIG. 7 and the observation images of FIGS. 12 to 19 described later, an optical material (specifically, the lens component constituting the most object-side surface of the objective lens group G11 has a Knoop hardness of 1500 or more) Even when the optical system 1d formed of sapphire is used, it is possible to capture an image of the sample to be observed while ensuring sufficient image quality.

[Second Embodiment]
Hereinafter, an optical system used in the microscope according to the second embodiment will be described with reference to FIGS. However, the microscope of this embodiment differs from the microscope M of the first embodiment only in the configuration of the objective lens group and the first imaging lens group. Only the configuration and numerical data of the objective lens group and the first imaging lens group, and numerical data related to the entire optical system will be described.

  With reference to FIGS. 8-10, the structure of the optical system (objective optical system for microscopes) of 2nd Embodiment is demonstrated in detail. In the sectional views along the optical axis of each lens group shown in FIGS. 8 to 10, the numbers r1, r2,... And d1, d2,. It corresponds to. In numerical data to be described later, s represents a surface number, r represents a radius of curvature of each surface, d represents a surface spacing, nd represents a refractive index in the d line, and νd represents an Abbe number in the d line.

  As shown in FIG. 8, the optical system of the second embodiment includes an objective lens group G21, a first imaging lens group G22, and a second imaging lens group, which are arranged in order from the object side on the optical axis Lc. And G13.

  An image of the sample to be observed (an image located on the object plane O) is formed once on the first image plane IM1 by the objective lens group G21. The image formed on the first image plane IM1 is formed again on the second image plane IM2 by the first imaging lens group G22 and the second imaging lens group G13. The second image plane IM2 coincides with the imaging plane of the imaging element of the portable information terminal P, and the image formed on the plane is displayed on the display of the portable information terminal P.

  As shown in FIG. 9, the objective lens group G21 includes, in order from the object side, a lens L41 that is a flat lens, a lens L42 that has a positive refractive power and a convex surface facing the image side, and a positive lens. A lens L43 that is a meniscus lens having a refractive power and having a convex surface facing the image side, a lens L44 that has a negative refractive power and having a concave surface facing the image side, and a biconvex lens having a positive refractive power Lens L45, a lens L46 which is a meniscus lens having negative refractive power and having a concave surface facing the image side, and a lens L47 which is a biconvex lens having positive refractive power.

  In the objective lens group G21, the lens L41 and the lens L42 are joined, the lens L44 and the lens L45 are joined, and the lens L46 and the lens L47 are joined. Further, the objective lens group G21 is configured such that water exists between the sample and the most object side of the objective lens group G21 during observation.

  Here, the lens component (lens L41) constituting the most object-side surface of the objective lens group G21 is formed of an optical material (specifically, sapphire) having a Knoop hardness of 1500 or more. As a result, the most object-side surface has sufficient hardness, so even if the sample is directly placed on the surface itself, the surface is hardly damaged. In the optical system of the second embodiment, since it is not affected by the scratches thus formed, a clear observation image can be obtained regardless of the type of sample or the method of placing the sample. .

  The surface data relating to the objective lens group G21 is shown below.

  As shown in FIG. 10, the first imaging lens group G22 has a positive refractive power, a lens L51 which is a meniscus lens having a concave surface facing the image side, and a lens L52 which is a biconvex lens having a positive refractive power. And a lens L53, which is a plano-convex lens having a positive refractive power and having a flat surface facing the image side, and a lens L54, which is a flat lens.

  In the first imaging lens group G22, the lens L51 and the lens L52 are cemented.

  The surface data relating to the first imaging lens group G12 is shown below.

  FIG. 11 is an aberration diagram related to the entire optical system according to the second embodiment. In FIG. 11, FIG. 11A shows spherical aberration (SA (mm)), FIG. 11B shows astigmatism (AST (mm)), and FIG. 11C shows distortion aberration (DIS (%)). In FIG. 11A (spherical aberration), the solid line indicates the F line, the broken line indicates the d line, and the alternate long and short dash line indicates the C line aberration. In FIG. 11B (astigmatism), a solid line indicates a tangential plane and a broken line indicates a sagittal plane.

  As is apparent from the aberration diagram of FIG. 11 and the observed images of FIGS. 12 to 19 described later, the lens component constituting the most object-side surface of the objective lens group G21 is an optical material having a Knoop hardness of 1500 or more (specifically Even when the optical system of the second embodiment formed of sapphire is used, it is possible to capture an image of the sample to be observed while ensuring sufficient image quality.

[Other Embodiments]
Although the illustrated embodiment has been described above, the present invention is not limited to such a form.

  For example, in the above embodiment, sapphire is used as the optical material of the lens component that constitutes the most object-side surface of the optical system that is the mounting surface of the sample. However, even if it is other than sapphire, the same effect can be obtained as long as the Knoop hardness is 1500 or more.

[Experiment data]
12 to 19 show images observed by a microscope equipped with any one of the optical systems described above. 12 is Escherichia coli (about 3 μm), FIG. 13 is Salmonella (about 2 μm), FIG. 14 is S. aureus (about 1 μm), FIG. 15 is Pseudomonas aeruginosa (about 3 μm), and FIG. 16 is black mold spores (about 4 μm). 17 is an observation image of yeast (Candida) (about 5 μm), FIG. 18 is an observation image of wine yeast (about 5 μm), and FIG. 19 is an observation image of oral bacteria (about 0.5 to 10 μm).

DESCRIPTION OF SYMBOLS 1 ... Microscope main body, 1a ... Housing | casing, 1b ... Sample mounting part, 1c ... Light source, 1d ... Optical system (microscope objective optical system), 1d1, G11 ... Objective lens group, 1d2, G12 ... 1st imaging lens Group, 2 ... mounting table, 2a ... mounting plate, 2b ... support leg, 2c ... transparent window, IM1 ... first image plane, IM2 ... second image plane, Lc ... optical axis, M ... microscope, m ... mirror, O: Object plane, P: Portable information terminal, P1, G13: Camera lens (second imaging lens group).

Claims (3)

An objective optical system for a microscope used for a microscope that captures an image of a sample to be observed by a camera function provided in a portable information terminal and displays a photographed image on a display of the portable information terminal,
The specimen is placed in contact with or adjacent to the most object-side surface,
The objective optical system for a microscope, wherein the lens component constituting the surface closest to the object is formed of an optical material having a Knoop hardness of 1500 or more. An objective optical system for a microscope used for a microscope that captures an image of a sample to be observed by a camera function provided in a portable information terminal and displays a photographed image on a display of the portable information terminal,
The specimen is placed in contact with or adjacent to the most object-side surface,
2. The microscope objective optical system according to claim 1, wherein the lens component constituting the most object side surface is sapphire. A microscope comprising the microscope objective optical system according to claim 1 or 2,
A microscope main body, and a mounting table connected to the microscope main body on which the portable information terminal is mounted;
The microscope main body has a sample placement unit for placing the sample,
The objective lens group of the objective optical system for a microscope is arranged inside the microscope main body so that the most object side surface of the objective lens group is exposed at the sample mounting portion. microscope.