Imaging lens, imaging device and capillary gel electrophoresis apparatus

Abstract

The invention provides an imaging lens, an imaging device and a capillary gel electrophoresis instrument, and relates to the technical field of capillary gel electrophoresis. The imaging device comprises a grating, an imaging lens and an imaging element. The grating diffracts light emitted by a sample to form diffracted light of different wavelengths corresponding to different sample points. The imaging lens comprises a first lens with positive focal length, a second lens with negative focal length, a third lens with positive focal length and a fourth lens with positive focal length, which are arranged in sequence. The imaging element images the imaging light calibrated by the imaging lens on an imaging target surface. When the first lens can be omitted, the imaging device does not need to adjust the angle of the imaging lens and does not affect the imaging quality.

Description

Technical Field

[0001] The invention relates to the technical field of capillary gel electrophoresis, and in particular to an imaging lens, an imaging device and a capillary gel electrophoresis instrument. Background Art

[0002] The imaging part of the capillary gel electrophoresis instrument adopts a hyperspectral imaging method, which combines imaging technology and spectral technology. It can simultaneously obtain the spatial information and spectral information of the target object. What is obtained through the hyperspectral device is a data cube. While obtaining the spatial information of each capillary, the spectral information of each capillary can also be recorded. By recording the spatial and spectral data at different time points, the chromatogram of capillary gel electrophoresis is finally obtained. Specifically, the imaging part of the capillary gel electrophoresis mainly adopts the form of grating 40 splitting. Existing optical imaging systems such as Figure 1 As shown, the optical lens in the first lens 20 collects the divergent light emitted by the sample placed in the capillary array 10 and converts it into parallel light. The first lens 20 is used for light beam collimation. After that, the parallel light is split by the grating 40 and then converged onto the camera 50 for imaging through the optical lens in the second lens 30. The second lens 30 is used for light beam convergence imaging.

[0003] The imaging optical path of the imaging part of the above-mentioned existing electrophoresis instrument also has the following defects: first, two lenses are required to complete the imaging, and the optical path cost is relatively high. Secondly, in the capillary gel electrophoresis imaging part, the grating 40 disperses the incident light emitted by the sample into lights of different wavelengths to facilitate the detection of fluorescence signals of specific wavelengths. Due to the diffraction characteristics of the grating 40, lights of different wavelengths will be diffracted at different angles, which requires that the second lens 30 must be precisely aligned with the diffraction angle to ensure that the detected fluorescence signal can be accurately focused on the corresponding position of the camera 50. Therefore, the second lens 30 must be adjusted according to the diffraction angle of the grating 40, but the installation and adjustment is difficult. If the angle of the second lens 30 is improperly adjusted, the diffracted light may not be focused correctly, resulting in blurred images and low signal-to-noise ratio of the chromatogram. Summary of the invention

[0004] The object of the present invention is to provide an imaging lens, an imaging device and a capillary gel electrophoresis instrument, so as to reduce the optical path cost and simplify the angle adjustment workflow of the lens for convergent imaging without affecting the imaging quality.

[0005] To achieve the above purpose, the technical solution of the embodiment of the present invention is as follows:

[0006] An imaging lens, comprising:

[0007] A first lens with positive refractive power, a second lens with negative refractive power, a third lens with positive refractive power and a fourth lens with positive refractive power are arranged in sequence.

[0008] Furthermore,

[0009] The focal length of the first lens satisfies the following relationship:

[0010] 36.2 < fL1 < 42.4, where fL1 represents the focal length of the first lens.

[0011] Furthermore,

[0012] The focal length of the second lens satisfies the following relationship:

[0013] -57.5 < fL2 < -51.3, where fL2 represents the focal length of the second lens.

[0014] Furthermore,

[0015] The focal lengths of the third lens and the fourth lens are both greater than the focal length of the first lens.

[0016] Furthermore,

[0017] The focal length of the third lens satisfies the following relationship: 86.1 < fL3 < 93.3, where fL3 represents the focal length of the third lens, or / and;

[0018] The focal length of the fourth lens satisfies the following relationship: 51.6 < fL4 < 57.1, where fL4 represents the focal length of the fourth lens.

[0019] Furthermore,

[0020] The distance between the first lens and the second lens is 0.7 - 0.9 mm, the distance between the second lens and the third lens is 0.1 - 0.2 mm, and the distance between the third lens and the fourth lens is 47.5 - 49.2 mm.

[0021] An imaging device, comprising:

[0022] A grating, disposed on one side of the sample, for diffracting the light emitted by the sample to form diffracted light of different wavelengths corresponding to different sample points;

[0023] An imaging lens as described in any one of the foregoing, disposed on the side of the grating away from the sample;

[0024] An imaging element, disposed on the side of the imaging lens away from the grating, for imaging the imaging light rays calibrated by the imaging lens on an imaging target surface.

[0025] Furthermore,

[0026] The distance between the fourth lens of the imaging lens and the imaging target surface is 14.1-16.3 mm.

[0027] A capillary gel electrophoresis instrument comprises a capillary array for placing samples, an illumination device for providing illumination light, and any of the above-mentioned imaging devices for imaging the capillary array.

[0028] Furthermore,

[0029] The capillary array is spaced 90-110 mm from the grating.

[0030] Compared with the prior art, the embodiments of the present invention have at least the following technical effects:

[0031] The imaging lens of the embodiment of the present invention comprises a first lens with positive focal power, a second lens with negative focal power, a third lens with positive focal power and a fourth lens with positive focal power which are arranged in sequence.

[0032] An imaging device according to an embodiment of the present invention includes a grating, an imaging lens and an imaging element. The grating is arranged on one side of a sample and is used to diffract light emitted by the sample to form diffracted light of different wavelengths corresponding to different sample points. The imaging lens is arranged on a side of the grating away from the sample. The imaging lens includes a first lens with positive focal length, a second lens with negative focal length, a third lens with positive focal length and a fourth lens with positive focal length, which are arranged in sequence. The imaging element is arranged on a side of the imaging lens away from the grating and is used to image the imaging light calibrated by the imaging lens on an imaging target surface. By means of the specific focal length type settings of the first lens, the second lens, the third lens and the fourth lens in the imaging lens, the imaging device can omit the first lens without adjusting the angle of the imaging lens and will not affect the imaging quality.

[0033] The capillary gel electrophoresis apparatus provided in the above embodiment belongs to the same concept as the imaging device embodiment, and thus has the same technical effect as the corresponding imaging device embodiment, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of an optical imaging system in the prior art;

[0035] Figure 2 is a YZ cross-sectional schematic diagram of an imaging device in one embodiment;

[0036] Figure 3 is a schematic diagram of an XZ cross section of an imaging device in one embodiment;

[0037] Figure 4 is a diagram showing the position arrangement of four lenses of an imaging lens in one embodiment;

[0038] Figure 5 This is a graph showing the MTF performance index of an embodiment when the characteristic wavelength of visible light is 486 nm;

[0039] Figure 6 This is a graph showing the MTF performance index of an embodiment when the characteristic wavelength of visible light is 588 nm;

[0040] Figure 7 This is a graph showing the MTF performance index of an embodiment when the characteristic wavelength of visible light is 656 nm;

[0041] Figure 8 This is a star point diagram of an embodiment when the characteristic wavelength of visible light is 486 nm;

[0042] Fig. 9 is a star point diagram of an embodiment when the characteristic wavelength of visible light is 588 nm;

[0043] Fig.10 FIG. 4 is a star point diagram of an embodiment when the characteristic wavelength of visible light is 656 nm.

[0044] Description of Figure Numbers:

[0045] 10. Capillary array; 20. First lens; 30. Second lens; 40. Grating; 50. Camera;

[0046] 60, imaging lens; 61, first lens; 62, second lens; 63, third lens; 64, fourth lens;

[0047] 70. Imaging target surface. DETAILED DESCRIPTION

[0048] The technical solution of the present invention is further elaborated in detail below in conjunction with the drawings and specific embodiments of the specification. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. In the following description, the expression "some embodiments" is related to a subset of all possible embodiments, but it should be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0049] It should also be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "inside", "outside", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0050] like Figure 2-4 As shown, in one embodiment of the invention, an imaging device includes a grating 40, an imaging lens 60 and an imaging element. The grating 40 diffracts the light emitted by the sample to form diffracted light of different wavelengths corresponding to different sample points. The imaging lens 60 includes a first lens 61 with positive optical power, a second lens 62 with negative optical power, a third lens 63 with positive optical power and a fourth lens 64 with positive optical power arranged in sequence. The imaging element images the imaging light calibrated by the imaging lens 60 on an imaging target surface 70 in the imaging element.

[0051] The existing optical imaging system uses the first lens 20 to collect the divergent light emitted by the sample and convert it into parallel light. That is, first, the divergent light emitted by the sample needs to be collected by the first lens 20 and then collimated into parallel light for the grating 40 to split. Secondly, after the grating 40 splits the light, it is diffracted out as parallel light. Due to the diffraction characteristics of the grating 40, light of different wavelengths will be diffracted at different angles. It is necessary to adjust the angle of the lens according to the diffraction angle of the grating 40. That is to say, in the existing optical imaging system, to complete the imaging in the camera 50, the first lens 20 is required to collimate the light beam and adjust the angle of the lens accordingly before the grating 40 splits the light. However, in the present invention, the first lens 20 is cancelled, and the first lens 20 is no longer needed to collimate the divergent light beam emitted by the sample. Only the grating 40 and the imaging lens 60 arranged on the rear side of the grating 40 are used. The grating 40 diffracts the emitted light emitted by the sample, and then it is received by the imaging lens 60. Four lenses arranged at intervals are provided in the imaging lens 60, including a first lens 61 with positive optical focal length, a second lens 62 with negative optical focal length, a third lens 63 with positive optical focal length and a fourth lens 64 with positive optical focal length, which are arranged in sequence. That is, the first lens 61 is first used to converge the light beam, and then the second lens 62 is used to diverge the light beam, and then the third lens 63 and the fourth lens 64 are used to converge the light beam. By setting the focal length types of the four lenses, the first lens 20 can be eliminated, and the angle adjustment process of the second lens 30 can also be simplified without affecting the imaging quality.

[0052] See also Figure 2-4 , Figure 2This is a schematic diagram of the YZ cross section of an imaging device in an embodiment of the invention, which is the imaging direction of the spectral dimension. The figure only shows the light of the +1 level of the spectrum. Figure 3 The schematic diagram of the imaging device in the XZ section in one embodiment of the invention. This direction is the imaging of the spatial dimension. In the above embodiment, the grating 40 is arranged on one side of the sample, and the light emitted by the sample to be measured arranged in the capillary array 10 is diffracted. The light emitted by the sample is dispersed according to the wavelength at the grating 40 to form diffracted light of different wavelengths corresponding to different sample points. The imaging lens 60 includes a first lens 61 with positive focal power, a second lens 62 with negative focal power, a third lens 63 with positive focal power, and a fourth lens 64 with positive focal power arranged in sequence. Finally, the imaging element images the imaging light calibrated by the imaging lens 60 on the imaging target surface 70. In the imaging lens 60, the diffracted light passes through the first lens 61, the second lens 62, the third lens 63 and the fourth lens 64 in sequence. The first lens 61 has a positive optical focal length, and the diffracted light is converged after the first lens 61. The second lens 62 has a negative optical focal length, and the diffracted light is diverged after the second lens 62. The third lens 63 and the fourth lens 64 both have positive optical focal lengths. The light emitted by the sample first passes through the grating 40 and is decomposed into diffracted light of different wavelengths. These diffracted lights then pass through the imaging lens 60. The first lens 61 and the second lens 62 are used to preliminarily adjust the focus and divergence of the light to adapt to the processing of subsequent lenses. The third lens 63 and the fourth lens 64 further calibrate the imaging light to ensure that the light can accurately form a clear image on the imaging target surface 70 of the imaging element. Compared with the existing optical imaging system, the imaging device of the embodiment of the present invention can reduce one first lens 20, and does not need the first lens 20 to complete the light beam collimation, thereby reducing the optical path cost, and can simplify the angle adjustment workflow of the second lens 30, reducing the difficulty of operation, while not affecting the imaging quality of the chromatogram image on the imaging target surface 70 of the imaging element.

[0053] In the performance test of optical imaging systems, modulation transfer function (MTF) and star diagram test are two commonly used evaluation methods. Specifically, Figure 5 This is a graph showing the MTF performance index of the above embodiment when the characteristic wavelength of visible light is 486nm. Figure 6 This is a graph showing the MTF performance index of the above embodiment when the characteristic wavelength of visible light is 588 nm. Figure 7 The MTF performance index of the above embodiment is shown in the case where the characteristic wavelength of visible light is 656 nm. Figure 5-7 It can be seen that under the full-band condition of visible light, the MTF performance index of the full field of view of imaging is greater than 0.2 at 50 line pairs, and the MTF value is greater than 0.2, indicating that the imaging quality of the above embodiment is good and can clearly reproduce the texture and details of the subject. Figure 8 The spot diagram for the above embodiment when the characteristic wavelength of visible light is 486 nm, Fig. 9 The spot diagram for the above embodiment when the characteristic wavelength of visible light is 588 nm, Fig.10 The spot diagram for the above embodiment when the characteristic wavelength of visible light is 656 nm. From Figure 8-10 it can be seen that under the condition of the full visible light band, the RMS radius of the spots in the full imaging field of view is less than 12 μm, which indicates that the imaging system of the above embodiment has high resolution, good focusing performance of the imaging system, can accurately focus the light onto the imaging plane, form a clear image, has high image quality, and the smaller RMS radius can indicate high image contrast, clear image details, no obvious blur or diffusion, indicating good stability of the imaging system within the full field of view and no significant aberrations or distortions.

[0054] In an embodiment of the invention, the focal length fL1 of the first lens 61 ranges from 36.2 < fL1 < 42.4, the focal length fL2 of the second lens 62 ranges from -57.5 < fL2 < -51.3, the focal lengths fL3 of the third lens 63 and fL4 of the fourth lens 64 are both greater than the focal length fL1 of the first lens 61, the focal length fL3 of the third lens 63 ranges from 86.1 < fL3 < 93.3, and the focal length fL4 of the fourth lens 64 ranges from 51.6 < fL4 < 57.1. The specific parameter settings of the focal length ranges of the lenses in the lens group ensure the optimization of the optical path, reduce aberrations and distortions, and improve the clarity and accuracy of imaging.

[0055] As Figure 2-4 shown, in an embodiment of the invention, the grating 40 is a 300-line grating 40, the thickness of the grating 40 is 3 mm, the sample is disposed in the capillary array 10 of the capillary electrophoresis instrument, and the spacing range between the capillary array 10 and the grating 40 is 90 - 110 mm. The use of the 300-line grating 40 and the appropriate thickness of the grating 40, combined with the appropriate spacing between the capillary array 10 and the grating 40, can improve the detection sensitivity of the sample.

[0056] In an embodiment of the invention, the focal length of the imaging lens 60 is 50 mm, and the imaging object-side field of view of the imaging lens 60 is 10 mm. The setting of the object-side field of view and the focal length of the imaging lens 60 enables the imaging device of the invention embodiment to adapt to samples of different sizes and provide a flexible imaging range.

[0057] In one embodiment of the invention, the distance between the fourth lens 64 of the imaging lens 60 and the imaging target surface 70 is in the range of 14.1-16.3. The distance range of 14.1-16.3 provides a suitable working distance between the fourth lens 64 and the imaging target surface 70. This distance can ensure that the imaging light has enough space for proper focusing and adjustment before reaching the imaging target surface 70, thereby obtaining a clear imaging effect.

[0058] like Figure 2-4 As shown, in one embodiment of the invention, the spacing between the first lens 61 and the second lens 62 is in the range of 0.7-0.9 mm, the spacing between the second lens 62 and the third lens 63 is in the range of 0.1-0.2 mm, and the spacing between the third lens 63 and the fourth lens 64 is in the range of 47.5-49.2 mm. By accurately setting the spacing between the lenses, the propagation path of the light in the lens group can be accurately controlled, thereby optimizing the imaging quality. Appropriate lens spacing helps to reduce optical distortion, such as spherical distortion and chromatic aberration, and appropriate lens spacing helps to improve imaging contrast.

[0059] In one embodiment of the invention, the left radius of the first lens 61 is 128.6 mm, the right radius of the first lens 61 is -35.2 mm, the thickness of the first lens 61 is 15 mm, the refractive index of the first lens 61 is 1.7, and the Abbe number of the first lens 61 is 41.6. The combination of the left radius of 128.6 mm and the right radius of -35.2 mm helps to control the focusing behavior of light, reduce spherical aberration, and thus improve the imaging quality. The positive left radius and the negative right radius are used to achieve better light collection and focusing. The specific parameter settings of the above lenses help to provide high-definition and high-contrast imaging, help to optimize the optical path, reduce aberrations and distortions, and thus improve the imaging quality.

[0060] In one embodiment of the invention, the left radius of the second lens 62 is -33.9 mm, the right radius of the second lens 62 is -89.6 mm, the thickness of the second lens 62 is 1 mm, the refractive index of the second lens 62 is 2, and the Abbe number of the second lens 62 is 20.7. The left radius and the right radius of the second lens 62 are both negative values. The second lens 62 is a concave lens, which helps to diverge light and can be used in an optical system to correct aberrations, such as spherical aberration and chromatic aberration. The specific parameter settings of the above lenses help to provide high-definition and high-contrast imaging, help to optimize the optical path, reduce aberrations and distortion, and thus improve imaging quality.

[0061] In one embodiment of the invention, the left radius of the third lens 63 is 77.3 mm, the thickness of the third lens 63 is 2.72 mm, the refractive index of the third lens 63 is 1.8, and the Abbe number of the third lens 63 is 40.6. The left radius of 77.3 mm indicates that the left side surface of the third lens 63 is convex, which helps to converge the light passing through it and can be used for light collection and focusing in the optical system. The specific parameter settings of the above lenses help to provide high-definition and high-contrast imaging, help to optimize the optical path, reduce aberrations and distortion, and thus improve imaging quality.

[0062] In one embodiment of the invention, the left radius of the fourth lens 64 is 37.7 mm, the right radius of the fourth lens 64 is 101 mm, the thickness of the fourth lens 64 is 14.1 mm, the refractive index of the fourth lens 64 is 2, and the Abbe number of the fourth lens 64 is 28.3. The left radius of the fourth lens 64 is 37.7 mm, and the right radius is 101 mm, both of which are positive values, that is, the fourth lens 64 helps to converge light, and the specific parameter settings of the above lenses help to provide high-definition and high-contrast imaging, help to optimize the optical path, reduce aberrations and distortions, and thus improve imaging quality.

[0063] A capillary gel electrophoresis instrument comprises a capillary array 10 for placing samples, an illumination device for providing illumination light, and any of the aforementioned imaging devices for imaging the capillary array 10.

[0064] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. The protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An imaging device, characterized in that: Comprising: A grating, disposed on one side of the sample, for diffracting the light emitted by the sample to form diffracted light of different wavelengths corresponding to different sample points; An imaging lens, composed of a first lens with a positive focal length, a second lens with a negative focal length, a third lens with a positive focal length, and a fourth lens with a positive focal length arranged in sequence. The first lens, the second lens, the third lens, and the fourth lens are all spherical lenses. The imaging lens is disposed on the side of the grating away from the sample; An imaging element, disposed on the side of the imaging lens away from the grating, for imaging the imaging light rays calibrated by the imaging lens on an imaging target surface; The focal length of the first lens satisfies the following relationship: 36.2mm < fL1 < 42.4mm, where fL1 represents the focal length of the first lens; The focal length of the second lens satisfies the following relationship: -57.5mm < fL2 < -51.3mm, where fL2 represents the focal length of the second lens; The focal length of the third lens satisfies the following relationship: 86.1mm < fL3 < 93.3mm, where fL3 represents the focal length of the third lens; The focal length of the fourth lens satisfies the following relationship: 51.6mm < fL4 < 57.1mm, where fL4 represents the focal length of the fourth lens.

2. The imaging device according to claim 1, characterized in that The distance between the first lens and the second lens ranges from 0.7 - 0.9 mm, the distance between the second lens and the third lens ranges from 0.1 - 0.2 mm, and the distance between the third lens and the fourth lens ranges from 47.5 - 49.2 mm.

3. The imaging device according to claim 1, characterized in that The distance between the fourth lens of the imaging lens and the imaging target surface ranges from 14.1 - 16.3mm.

4. A capillary gel electrophoresis apparatus, characterized in that: Comprising a capillary array for placing a sample, an illumination device for providing illumination light, and an imaging device as described in any one of claims 1 - 3 for imaging the capillary array.

5. The capillary gel electrophoresis apparatus according to claim 4, characterized in that: The distance between the capillary array and the grating ranges from 90 - 110mm.

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