A liquid-free microscope optical system with large field of view, high resolution and large working distance

Abstract

The present invention relates to a large-field-of-view, high-resolution, and large-working-distance aneroid microscope optical system, comprising a glass slide, a collimator lens group, an emission filter, and a Gaussian-like lens group arranged sequentially from the object plane to the image plane; an achromatic lens group or an achromatic lens is arranged at at least one position between the collimator lens group and the emission filter, or between the emission filter and the Gaussian-like lens group; the resulting microscope optical system has a numerical aperture of 0.45-0.55, a magnification of 5-10 times, an object-space field of view diameter of 4mm-6mm, an object-space resolution of 0.4μm-0.6μm, a working distance of 2mm-3mm, and a visible light wavelength range of 460nm-680nm. The microscope optical system has an MTF value close to the diffraction limit within the entire field of view of the working band, and a relative distortion of less than 1% within the entire field of view of the working band. Compared with traditional objective lenses with the same field of view, the system has higher imaging resolution, smaller relative distortion, and a larger working distance.

Description

Technical Field

[0001] The invention belongs to the field of optics, and in particular relates to a liquid-free microscope optical system with large viewing field, high resolution and large working distance. Background Art

[0002] In order to distinguish and examine the fine structure of biological sample tissues, a microscopic optical system with a large field of view and high resolution is required. However, the existing microscopic optical systems (traditional optical microscopes, electron microscopes, confocal microscopes and even the most advanced two-photon microscopes in recent years) and in vivo imaging equipment are difficult to achieve high-resolution and large-field imaging without the involvement of liquid media. In order to obtain large-field imaging at high resolution, it is necessary to increase the aperture of the microscopic imaging optical system. However, due to the influence of the off-axis aberration of the lens, the paraxial magnification and the off-axis magnification in the multi-lens imaging process do not match, resulting in large distortion at the edge of the large field of view, which greatly affects the observation of the fine structure of biological sample tissues. The existing microscopic optical systems have inherent limitations in terms of large field of view and high resolution indicators, and cannot be optimized at the same time. They cannot meet the research needs of life sciences and are in urgent need of improvement and breakthroughs. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a liquid-free microscope optical system with a large field of view, high resolution and large working distance.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a large-field-of-view, high-resolution, and large-working-distance aneroid microscope optical system, comprising a glass slide, a collimating lens group, an emission filter, and a Gaussian-like lens group arranged in sequence from the object plane to the image plane; an achromatic lens group or an achromatic lens is arranged at at least one position between the collimating lens group and the emission filter and between the emission filter and the Gaussian-like lens group; the resulting microscope optical system has a numerical aperture of 0.45-0.55, a magnification of 5-10 times, an object-side field of view diameter of 4mm-6mm, an object-side resolution of 0.4μm-0.6μm, a working distance of 2mm-3mm, and a visible light wavelength range of 460nm-680nm.

[0005] Furthermore, the collimating lens group includes a first concave-convex lens, a second concave-convex lens, a third concave-convex lens, a first biconvex lens, a fourth concave-convex lens, a first biconcave lens, a second biconvex lens, and a fifth concave-convex lens arranged in sequence along the optical axis.

[0006] Furthermore, the achromatic lens group includes a third biconvex lens, a first convex-concave lens, and a second biconcave lens arranged in sequence along the optical axis, and its function is to eliminate system chromatic aberration.

[0007] Furthermore, the Gaussian-like lens group includes a third biconcave lens, a sixth concave-convex lens, a second convex-concave lens, and a third convex-concave lens arranged in sequence along the optical axis, and its function is to shorten the object-image conjugate distance.

[0008] Furthermore, the microscope optical system has object-space telecenter and image-space telecenter, and the object-space working distance is 2 mm to 3 mm.

[0009] Furthermore, the initial structure of the objective lens of the microscopic optical system is in the form of mainly using the structure of the microscopic objective lens while taking into account the structural features of the photolithography objective lens.

[0010] Furthermore, the microscopic optical system does not have liquid as a medium.

[0011] The present invention has the following beneficial effects: Based on the above technical solution, utilizing existing computer-aided optical design and optimization software, the number and structure of lens groups are rationally selected, and the position and parameters of each lens group are optimized. All lenses are made of common commercial glass, reducing the difficulty of sourcing materials and manufacturing costs for the optical system. All lenses are spherical and coaxially positioned, facilitating processing and assembly. The MTF value of the microscope optical system approaches the diffraction limit within the entire field of view of the operating wavelength band, and the relative distortion is less than 1% within the entire field of view of the operating wavelength band. Compared with traditional objective lenses with the same field of view, the system has higher imaging resolution, less relative distortion, and a larger working distance, and does not require the presence of a liquid medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 An optical system diagram of an objective lens of a microscope optical system according to a preferred embodiment of the present invention;

[0013] Figure 2 A modulation transfer function diagram of an objective lens of a microscope optical system according to a preferred embodiment of the present invention;

[0014] Figure 3 A spot diagram of an objective lens of a microscope optical system according to a preferred embodiment of the present invention;

[0015] Figure 4 Graph showing the field curvature and distortion of the objective lens of a microscope optical system according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0016] In order to enable ordinary technicians in this field to more clearly understand the objectives, technical solutions and advantages of the present invention, the present invention is further explained below with reference to the accompanying drawings and embodiments, but the present invention is not limited to the following embodiments.

[0017] The present invention will be further described below through examples with reference to the accompanying drawings.

[0018] Example: See Figures 1-4This embodiment relates to a large-field-of-view, high-resolution, and long-working-distance aneroid microscope. The microscope objective lens has a magnification of 10x, a numerical aperture of 0.5, a visible light wavelength range of 460nm-680nm, an object-space field of view diameter of 6mm, and an object-space resolution of 0.5μm. The microscope objective lens structure is primarily based on a microscope objective lens while also incorporating structural features of a photolithography objective lens. The microscope objective lens achieves a large numerical aperture, providing improved diffraction-limited spatial resolution.

[0019] like Figure 1 As shown, the objective lens of the microscope optical system includes a slide S, a collimating lens group G1, an emission filter F, an achromatic lens group G2, and a Gaussian-like lens group G3, which are arranged in sequence from the object plane to the image plane P.

[0020] The collimating lens group G1 uses a combination of positive and negative lenses to correct aberrations, including a first meniscus lens L1, a second meniscus lens L2, a third meniscus lens L3, a first biconvex lens L4, a fourth meniscus lens L5, a first biconcave lens L6, a second biconcave lens L7, and a fifth meniscus lens L8, which are arranged in sequence along the optical axis. The achromatic lens group G2 uses a combination of crown glass and flint glass to correct chromatic aberrations, including a third biconvex lens L9, a first meniscus lens L10, and a second biconcave lens L11, which are arranged in sequence along the optical axis. The Gaussian-like lens group G3 adopts a structure in which the positive and negative lens groups are separated, with the negative group in front, including a third biconcave lens L12, a sixth meniscus lens L13, a second meniscus lens L14, and a third meniscus lens L15, which are arranged in sequence along the optical axis. The microscope optical system uses a Gaussian-like lens group G3, which is a deformation of a Gaussian lens group, to shorten the object-image conjugate distance.

[0021] Taking energy and stability into consideration, high-transmittance lens materials are selected during the design process to reduce lens thickness while ensuring high imaging quality, thereby ensuring low energy loss for the overall system.

[0022] The objective lens of the microscope optical system takes into account both object-space telecentricity and image-space telecentricity. The constant proportional relationship between the object and the image is determined by the object-space telecentricity, and the uniform illumination of the image surface is determined by the image-space telecentricity, which makes the objective lens have the advantages of small distortion, large depth of field, high resolution and small vignetting.

[0023] Image quality analysis of microscope objective lens Figure 2-Figure 4 .like Figure 2 As shown in Figure 1, the modulation transfer function (MTF) value of the microscope objective lens is close to the diffraction limit within the full field of view of the working band, leaving a large margin for subsequent adjustment. Figure 3 As shown in Figure 2, the root mean square radius of the diffuse spot of the microscope objective lens is less than 12 μm within the full field of view of the working band; Figure 4 As shown, the relative distortion of the objective lens of the microscope optical system is less than 1% within the full field of view of the working band.

[0024] The specific embodiments of the present invention described above do not limit the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A liquid-free microscope optical system with large field of view, high resolution and large working distance, characterized in that: The invention comprises a glass slide (S), a collimating lens group (G1), an emission filter (F), and a Gaussian lens group (G3) arranged in sequence from the object plane to the image plane (P); an achromatic lens group (G2) or an achromatic lens is arranged at at least one position between the collimating lens group (G1) and the emission filter (F) and between the emission filter (F) and the Gaussian lens group (G3); the obtained microscope optical system has a numerical aperture of 0.45-0.55, a magnification of 5-10 times, an object field diameter of 4mm-6mm, an object resolution of 0.4μm-0.6μm, a working distance of 2mm-3mm, and a visible light wavelength range of 460nm-680nm; the collimating lens group (G1) comprises a first concave-convex lens (L1), a second concave-convex lens (L2), a third concave-convex lens (L3), a first biconvex lens (L4), a fourth concave-convex lens (L5), a first biconcave lens (L6), a second biconvex lens (L7), and a fifth concave-convex lens (L8); the achromatic lens group (G2) includes a third biconvex lens (L9), a first convex-concave lens (L10), and a second biconcave lens (L11) arranged in sequence along the optical axis, and functions to eliminate system chromatic aberration; the Gaussian-like lens group (G3) includes a third biconcave lens (L12), a sixth concave-convex lens (L13), a second convex-concave lens (L14), and a third convex-concave lens (L15) arranged in sequence along the optical axis, and functions to shorten the object-image conjugate distance; The microscope optical system has object-space telecentricity and image-space telecentricity, and an object-space working distance of 2mm-3mm. The initial structure of the microscope optical system is mainly based on the microscope objective structure and has the structural characteristics of the photolithography objective lens. The microscope optical system does not use liquid as a medium.

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