A large-target achromatic microscope tube

Abstract

This invention relates to the field of microscopy technology and proposes a large-area achromatic microscope tube, comprising an aperture, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially along the incident light direction. The first, second, fourth, and sixth lenses are all biconvex lenses, while the third and fifth lenses are both biconcave lenses. The second and third lenses are combined to form a cemented doublet. This technical solution solves the problems of blurred edges and vignetting in existing microscope tubes used with high-resolution sensors.

Description

Technical Field

[0001] This utility model relates to the field of microscope technology, specifically to a large-target-area achromatic microscope tube. Background Technology

[0002] The technological development of microscope tubes is inextricably linked to the evolution of optical microscope systems, originating from the mid-20th century demand for modular and multifunctional microscopes. In traditional finite-distance optical systems, the fixed optical path of direct imaging by the objective lens limited functional expansion. However, with the advent of infinity-corrected optical systems, the tube lens began to play a crucial role as a key component. This system, by emitting parallel light through the objective lens and then focusing it again through the tube lens, allows optical accessories such as fluorescence modules and polarizers to be flexibly inserted into the optical path, greatly expanding the application range of microscopes.

[0003] Early microscope tube designs primarily revolved around standard focal lengths, such as Zeiss's 164mm and Olympus's 180mm. Subsequently, industrial inspection and research demands drove the development towards longer entrance pupil distances and lower aberrations to meet the needs of protective equipment integration and high-precision imaging. In modern applications, microscope tubes not only support fluorescence and confocal microscopy techniques in the life sciences but are also widely used in semiconductor inspection, industrial metrology, and machine vision systems, serving as a crucial link between objectives, eyepieces, and various optical accessories. With advancements in ultra-high-definition imaging and intelligent technologies, microscope tube designs continue to evolve towards greater compatibility and motorized focusing, constantly pushing the boundaries of microscopy technology.

[0004] However, traditional tube microscopes suffer from edge blurring and vignetting in high-resolution sensor applications, which means that microscopic imaging cannot fully cover the imaging area of ​​large-target scientific cameras.

[0005] Therefore, a new microscope tube is urgently needed. Utility Model Content

[0006] This invention proposes a large-target-area achromatic microscope tube, which solves the problems of blurred edges and vignetting in the application of high-resolution sensors in existing microscope tubes.

[0007] The technical solution of this utility model is as follows: a large target surface achromatic microscope tube, comprising an aperture, a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged sequentially along the incident direction of light, wherein the first lens, the second lens, the fourth lens and the sixth lens are all biconvex lenses, and the third lens and the fifth lens are both biconcave lenses;

[0008] The second lens and the third lens are combined to form a cemented doublet lens.

[0009] As a further technical solution, the distance between the aperture stop and the first lens is 60mm-140mm; the distance between the rear surface of the first lens and the front surface of the second lens is 4±0.3mm, the distance between the rear surface of the third lens and the front surface of the fourth lens is 2±0.1mm, the distance between the rear surface of the fourth lens and the front surface of the fifth lens is 12.5±0.8mm, the distance between the rear surface of the fifth lens and the front surface of the sixth lens is 18.2±1.3mm, and the distance between the rear surface of the sixth lens and the image plane is 36±1.7mm.

[0010] As a further technical solution, the first lens has an anterior surface radius of curvature of 56±2mm and a posterior surface radius of curvature of -1057±2mm; the second lens has an anterior surface radius of curvature of 77±2mm and a posterior surface radius of curvature of -520±2mm; the third lens has an anterior surface radius of curvature of -520±2mm and a posterior surface radius of curvature of 67±2mm; the fourth lens has an anterior surface radius of curvature of 82±2mm and a posterior surface radius of curvature of -135±2mm; the fifth lens has an anterior surface radius of curvature of -44±2mm and a posterior surface radius of curvature of 81±2mm; and the sixth lens has an anterior surface radius of curvature of 111±2mm and a posterior surface radius of curvature of -1050±2mm.

[0011] As a further technical solution, the first lens has a refractive index of 1.44 and a dispersion coefficient of 94.5; the second lens has a refractive index of 1.62 and a dispersion coefficient of 63.4; the third lens has a refractive index of 1.75 and a dispersion coefficient of 52.3; the fourth lens has a refractive index of 1.44 and a dispersion coefficient of 94.5; the fifth lens has a refractive index of 1.51 and a dispersion coefficient of 64.2; and the sixth lens has a refractive index of 1.83 and a dispersion coefficient of 37.2.

[0012] As a further technical solution, the effective diameter of the first lens is 48±1mm, and the center thickness of the lens is 10±0.5mm; the effective diameter of the second lens is 46±1mm, and the center thickness of the lens is 12±0.5mm; the effective diameter of the third lens is 46±1mm, and the center thickness of the lens is 14±0.5mm; the effective diameter of the fourth lens is 37±1mm, and the center thickness of the lens is 15±0.5mm; the effective diameter of the fifth lens is 31±1mm, and the center thickness of the lens is 12±0.5mm; and the effective diameter of the sixth lens is 36±1mm, and the center thickness of the lens is 7±0.5mm.

[0013] The beneficial effects of the large target surface achromatic microscope tube provided by this utility model are as follows:

[0014] First, the achromatic optimization solves the chromatic aberration problem in broadband imaging. In fluorescence microscopy and multispectral imaging applications, it can ensure that light of different wavelengths is accurately focused on the same focal plane, significantly improving the imaging fidelity of confocal microscopes and Raman spectroscopy systems.

[0015] Second, it breaks through the compatibility limitations of traditional endoscopes with fixed exit pupil distance on protective equipment (such as gas masks and goggles), making industrial inspection in hazardous environments possible.

[0016] Third, the electric adjustment of the entrance pupil distance enables seamless switching between human eye observation and camera framing, avoiding the cumbersome operation of physically replacing the adapter required by existing systems.

[0017] Fourth, the long entrance pupil distance creates optical interface conditions for the integration of AR / VR head-mounted displays and microscopes, promoting the development of remote collaborative microscopic diagnosis.

[0018] Fifth, the role of the tube lens in the optical path has been reconstructed, upgrading it from a simple imaging relay element to an intelligent optical hub. This retains the advantages of modular expansion of the infinity system while making up for its adaptability deficiencies in modern high-precision applications.

[0019] VI. The large image plane design effectively solves the problems of edge field blurring and vignetting that occur when traditional tube microscopes are adapted to high-resolution CMOS / CCD sensors, enabling microscopic imaging to fully cover the imaging area of ​​modern large-area scientific cameras. Attached Figure Description

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] Figure 1 This is a diagram showing the internal lens distribution of a large-target achromatic microscope tube when the entrance pupil distance is 60 mm.

[0022] Figure 2 The MTF optical modulation function is plotted when the entrance pupil distance is 60mm.

[0023] Figure 3 The MTF optical modulation function is plotted when the entrance pupil distance is 60mm.

[0024] Figure 4 This is a diagram showing the internal lens distribution of a large-target achromatic microscope tube when the entrance pupil distance is 140 mm.

[0025] Figure 5 The MTF optical modulation function is plotted when the entrance pupil distance is 140mm.

[0026] Figure 6 The MTF optical modulation function is plotted when the entrance pupil distance is 140mm.

[0027] Figure 7 This is a chromatic focal shift curve diagram of the optical system.

[0028] In the diagram: 1. Aperture; 2. First lens; 3. Second lens; 4. Third lens; 5. Fourth lens; 6. Fifth lens; 7. Sixth lens; 8. Image plane. Detailed Implementation

[0029] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this utility model.

[0030] like Figures 1 to 7 As shown, this utility model provides a large-target achromatic microscope tube, including an aperture 1, a first lens 2, a second lens 3, a third lens 4, a fourth lens 5, a fifth lens 6, and a sixth lens 7 arranged sequentially along the incident light direction. The first lens 2, the second lens 3, the fourth lens 5, and the sixth lens 7 are all biconvex lenses, and the third lens 4 and the fifth lens 6 are both biconcave lenses. The second lens 3 and the third lens 4 are combined to form a cemented doublet lens.

[0031] The distance between aperture 1 and the first lens 2 is 60mm-140mm; the distance between the rear surface of the first lens 2 and the front surface of the second lens 3 is 4±0.3mm, the distance between the rear surface of the third lens 4 and the front surface of the fourth lens 5 is 2±0.1mm, the distance between the rear surface of the fourth lens 5 and the front surface of the fifth lens 6 is 12.5±0.8mm, the distance between the rear surface of the fifth lens 6 and the front surface of the sixth lens 7 is 18.2±1.3mm, and the distance between the rear surface of the sixth lens 7 and the image plane 8 is 36±1.7mm.

[0032] The first lens 2 has a front surface radius of curvature of 56±2mm, a rear surface radius of curvature of -1057±2mm, a refractive index of 1.44, a dispersion coefficient of 94.5, an effective aperture of 48±1mm, and a center thickness of 10±0.5mm. The second lens 3 has a front surface radius of curvature of 77±2mm, a rear surface radius of curvature of -520±2mm, a refractive index of 1.62, a dispersion coefficient of 63.4, an effective aperture of 46±1mm, and a center thickness of 12±0.5mm. The third lens 4 has a front surface radius of curvature of -520±2mm, a rear surface radius of curvature of 67±2mm, a refractive index of 1.75, a dispersion coefficient of 52.3, an effective aperture of 46±1mm, and a center thickness of 14±0.5mm. The fourth lens 5 has an anterior surface radius of curvature of 82±2mm, a posterior surface radius of curvature of -135±2mm, a refractive index of 1.44, a dispersion coefficient of 94.5, an effective diameter of 37±1mm, and a center thickness of 15±0.5mm; the fifth lens 6 has an anterior surface radius of curvature of -44±2mm, a posterior surface radius of curvature of 81±2mm, a refractive index of 1.51, a dispersion coefficient of 64.2, an effective diameter of 31±1mm, and a center thickness of 12±0.5mm; the sixth lens 7 has an anterior surface radius of curvature of 111±2mm, a posterior surface radius of curvature of -1050±2mm, a refractive index of 1.83, a dispersion coefficient of 37.2, an effective diameter of 36±1mm, and a center thickness of 7±0.5mm.

[0033] In the design of an infinity optical system, the half-image height h, the half-field angle θ, and the lens focal length f have the following relationship: h = f * tanθ. For a given focal length, the larger θ is, the larger the resulting image plane (θ) becomes, allowing compatibility with more high-resolution cameras. When f = 200mm, θ = 6.28°, and the half-image height h = 22mm, it is compatible with full-frame cameras.

[0034] High-definition imaging requires the system to maintain a high modulation transfer function (MTF>0.3) at the Nyquist frequency (f_N=1 / 2p, p is the camera pixel size), which requires optimization of spherical aberration, coma, and diffraction limit.

[0035] Achromatic correction requires correcting axial chromatic aberration (focus shift of light at different wavelengths) and lateral chromatic aberration (difference in magnification of images at different wavelengths), and typically employs a combination of low-dispersion materials and cemented lenses.

[0036] This invention provides a beneficial effect for a large-target-area achromatic microscope tube:

[0037] First, the achromatic optimization solves the chromatic aberration problem in broadband imaging. In fluorescence microscopy and multispectral imaging applications, it can ensure that light of different wavelengths is accurately focused on the same focal plane, significantly improving the imaging fidelity of confocal microscopes and Raman spectroscopy systems.

[0038] Second, it breaks through the compatibility limitations of traditional endoscopes with fixed exit pupil distance on protective equipment (such as gas masks and goggles), making industrial inspection in hazardous environments possible.

[0039] Third, the electric adjustment of the entrance pupil distance enables seamless switching between human eye observation and camera framing, avoiding the cumbersome operation of physically replacing the adapter required by existing systems.

[0040] Fourth, the long entrance pupil distance creates optical interface conditions for the integration of AR / VR head-mounted displays and microscopes, promoting the development of remote collaborative microscopic diagnosis.

[0041] Fifth, the role of the tube lens in the optical path has been reconstructed, upgrading it from a simple imaging relay element to an intelligent optical hub. This retains the advantages of modular expansion of the infinity system while making up for its adaptability deficiencies in modern high-precision applications.

[0042] VI. The large image plane design effectively solves the problems of edge field blurring and vignetting that occur when traditional tube microscopes are adapted to high-resolution CMOS / CCD sensors, enabling microscopic imaging to fully cover the imaging area of ​​modern large-area scientific cameras.

[0043] When the large-area achromatic microscope tube provided by this utility model is applied to a microscope, it can achieve a change in entrance pupil distance from 60mm to 140mm with only one lens group and without changing the lens spacing, while ensuring high-quality and high-precision imaging. It retains the advantages of modular expansion of the infinity system, and can also achieve seamless switching between human eye observation and camera framing by electrically adjusting the entrance pupil distance, avoiding the cumbersome operation of physically replacing the adapter required by the existing system.

[0044] exist Figure 7 In the curve, the maximum difference between the left and right ends is 40 μm, meaning the color difference is 40 μm. Furthermore, from... Figures 1 to 7 As can be seen from the above, the large target surface achromatic microscope tube provided by this utility model has the characteristics of high resolution, low distortion, and low dispersion at an entrance pupil distance of 60mm-140mm, maintaining a high-quality imaging effect.

[0045] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A large target surface achromatic microscope tube characterized in that, It includes an aperture stop (1), a first lens (2), a second lens (3), a third lens (4), a fourth lens (5), a fifth lens (6), and a sixth lens (7) arranged sequentially along the incident direction of light. The first lens (2), the second lens (3), the fourth lens (5), and the sixth lens (7) are all biconvex lenses, and the third lens (4) and the fifth lens (6) are both biconcave lenses. The second lens (3) and the third lens (4) are combined to form a cemented doublet lens.

2. A large target area achromatic tube lens for a microscope according to claim 1, characterized in that The distance between the aperture stop (1) and the first lens (2) is 60mm-140mm; the distance between the rear surface of the first lens (2) and the front surface of the second lens (3) is 4±0.3mm; the distance between the rear surface of the third lens (4) and the front surface of the fourth lens (5) is 2±0.1mm; the distance between the rear surface of the fourth lens (5) and the front surface of the fifth lens (6) is 12.5±0.8mm; the distance between the rear surface of the fifth lens (6) and the front surface of the sixth lens (7) is 18.2±1.3mm; and the distance between the rear surface of the sixth lens (7) and the image plane (8) is 36±1.7mm.

3. A large target area achromatic tube lens for a microscope according to claim 2, wherein, The first lens (2) has a front surface radius of curvature of 56±2mm and a rear surface radius of curvature of -1057±2mm; the second lens (3) has a front surface radius of curvature of 77±2mm and a rear surface radius of curvature of -520±2mm; the third lens (4) has a front surface radius of curvature of -520±2mm and a rear surface radius of curvature of 67±2mm; the fourth lens (5) has a front surface radius of curvature of 82±2mm and a rear surface radius of curvature of -135±2mm; the fifth lens (6) has a front surface radius of curvature of -44±2mm and a rear surface radius of curvature of 81±2mm; and the sixth lens (7) has a front surface radius of curvature of 111±2mm and a rear surface radius of curvature of -1050±2mm.

4. A large target area achromatic tube lens for a microscope according to claim 3, wherein, The first lens (2) has a refractive index of 1.44 and a dispersion coefficient of 94.5; the second lens (3) has a refractive index of 1.62 and a dispersion coefficient of 63.4; the third lens (4) has a refractive index of 1.75 and a dispersion coefficient of 52.3; the fourth lens (5) has a refractive index of 1.44 and a dispersion coefficient of 94.5; the fifth lens (6) has a refractive index of 1.51 and a dispersion coefficient of 64.2; and the sixth lens (7) has a refractive index of 1.83 and a dispersion coefficient of 37.

2.

5. A large target area achromatic tube lens for a microscope according to claim 4, wherein, The effective aperture of the first lens (2) is 48±1mm, and the center thickness of the lens is 10±0.5mm; the effective aperture of the second lens (3) is 46±1mm, and the center thickness of the lens is 12±0.5mm; the effective aperture of the third lens (4) is 46±1mm, and the center thickness of the lens is 14±0.5mm; the effective aperture of the fourth lens (5) is 37±1mm, and the center thickness of the lens is 15±0.5mm; the effective aperture of the fifth lens (6) is 31±1mm, and the center thickness of the lens is 12±0.5mm; the effective aperture of the sixth lens (7) is 36±1mm, and the center thickness of the lens is 7±0.5mm.

Images