Microobjective with 40-time broadband long working distance

Abstract

The invention relates to the field of micro-objective lenses, in particular to a 40-time broadband long-working-distance microscope objective lens. The 40-time broadband long-working-distance microscope objective comprises a balsaming lens group G1, a balsaming lens group G2, a balsaming lens group G3, a lens group G4, a lens group G5 and a balsaming lens group G6 which are sequentially arranged along an optical axis from an image direction to an object space. Wherein the balsaming lens group G1 is located at one side of the balsaming lens group G2, the balsaming lens group G3 is located at one side, far away from the balsaming lens group G1, of the balsaming lens group G2, and the lens group G4 is located at one side, far away from the balsaming lens group G2, of the balsaming lens group G3. The 40-time broadband long working distance microscope objective provided by the invention covers a white light band of 436-700nm and an infrared band of 1400-1600nm, and repeated focusing is not needed when the two bands work simultaneously, so that the problems of time delay and positioning error caused by conversion are avoided, and potential damage to samples such as embryos and the like is reduced.

Description

Technical Field

[0001] The invention relates to the field of micro-objective lenses, and in particular to a 40-fold wide-band long-working-distance micro-objective lens. Background Art

[0002] Wideband microscope objective lenses have shown a wide range of application values ​​in many fields such as biomedicine and materials science. Especially in the semiconductor industry, wideband microscope objective lenses play a vital role in detecting film stress, critical dimensions, and wafer surface defects. In the field of assisted reproductive technology, core technical links such as embryo incubation and embryo cryopreservation often require precise micromanipulation, which not only requires extremely high precision, but also requires the use of non-cell-destructive laser wall breaking, drilling, cutting and other technical means. The current micromanipulation process is: first, microscopic imaging is completed under visible light illumination through conventional microscope objective lenses; then, it is switched to infrared laser microscope objective lenses for target calibration and micromanipulation. However, there is a problem of conversion time delay in this process. At the same time, due to the repeated positioning errors that may be caused by the conversion mechanism, micromanipulators must have a high degree of professional skills to ensure that potential damage to the embryo is minimized.

[0003] The cover glass material of traditional microscope objective design is usually H-K51 or H-K9 by default. However, for specific professional fields such as assisted reproduction, embryo hatching, embryo freezing, and living cell culture, the cover glass material is usually a composite of high borosilicate glass (PYREX) and optical grade polycarbonate (PC). These two materials have a refractive index and Abbe dispersion coefficient that are significantly different from H-K51 or H-K9. Traditional microscope objectives cannot eliminate the spherical aberration and dispersion generated when high borosilicate glass (PYREX) and optical grade polycarbonate (PC Abbe number 30, similar to flint glass) are used in combination. In this application scenario, the imaging quality will be significantly reduced, and the infrared laser focus position deviation will be large.

[0004] Therefore, it is necessary to provide a new 40-fold wide-band long-working-distance microscope objective to solve the above-mentioned technical problems. Summary of the invention

[0005] In order to overcome the defects of the prior art, a 40-fold wide-band long-working-distance microscope objective is provided to solve the above-mentioned problems.

[0006] The 40-fold wide-band long-working-distance microscope objective lens provided by the present invention comprises: a cemented lens group G1, a cemented lens group G2, a cemented lens group G3, a lens group G4, a lens group G5, and a cemented lens group G6 which are sequentially arranged along the optical axis from the image direction to the object side; wherein the cemented lens group G1 is located on one side of the cemented lens group G2, the cemented lens group G3 is located on the side of the cemented lens group G2 away from the cemented lens group G1, the lens group G4 is located on the side of the cemented lens group G3 away from the cemented lens group G2, the lens group G5 is located on the side of the lens group G4 away from the cemented lens group G3, and the cemented lens group G6 is located on the side of the lens group G5 away from the lens group G4; the cemented lens group G1 is composed of a double concave negative lens L1 and a double convex positive lens L2 which are sequentially arranged along the optical axis from the image direction to the object side, and the cemented lens group G2 is composed of a double concave negative lens L1 and a double convex positive lens L2 which are sequentially arranged along the optical axis from the image direction to the object side, and the cemented lens group G2 is composed of a double convex positive lens L2 which are sequentially arranged along the optical axis from the image direction to the object side, and the cemented lens group G2 is composed of a double convex positive lens L2 which are sequentially arranged along the optical axis from the image direction to the object side, and the cemented lens group G5 is located on the side of the lens group G4 away from the cemented lens group G4. The meniscus negative lens L3 and the biconvex positive lens L4 are sequentially arranged along the optical axis toward the object, and the concave surface of the meniscus negative lens L3 faces the object. The cemented lens group G3 is composed of a meniscus negative lens L5 and a biconvex positive lens L6, which are sequentially arranged along the optical axis from the image direction to the object, and the concave surface of the meniscus negative lens L5 faces the object. The lens group G4 includes a meniscus negative lens L7, and the meniscus negative lens L7 is located on the side of the biconvex positive lens L6 away from the meniscus negative lens L5, and the concave surface of the meniscus negative lens L7 faces the image. The lens group G5 includes a meniscus positive lens L8, and the meniscus positive lens L8 is located on the side of the meniscus negative lens L7 away from the biconvex positive lens L6, and the convex surface of the meniscus positive lens L8 faces the image. The cemented lens group G6 is composed of a flat plate lens L9 and a flat plate lens L10, which are sequentially arranged along the optical axis from the object direction to the image.

[0007] Preferably, the biconcave negative lens L1, the biconvex positive lens L2, the meniscus negative lens L7, and the meniscus positive lens L8 are all made of lanthanum optical glass.

[0008] Preferably, the biconvex positive lens L4 and the biconvex positive lens L6 are both made of phosphorus crown optical glass.

[0009] Preferably, the meniscus negative lens L3 is made of heavy flint optical glass.

[0010] Preferably, the meniscus negative lens L5 is made of light flint optical glass.

[0011] Preferably, the flat lens L9 is made of optical glass.

[0012] Preferably, the flat lens L10 is made of optical plastic.

[0013] Preferably, the focal length of the cemented lens group G1 is fG1, the focal length of the cemented lens group G2 is fG2, and the focal length of the cemented lens group G3 is fG3, and they satisfy the conditional formula: -85mm <fG1<-75mm,30mm<fG2<40mm,15mm<fG3<25mm。

[0014] Preferably, the focal length of the meniscus negative lens L7 is fL7, which satisfies the condition: -25 mm <fL7<-15mm。

[0015] Preferably, the focal length of the meniscus positive lens L8 is fL8, which satisfies the condition: 7 mm <fL8<11mm。

[0016] Compared with the related art, the 40-fold wide-band and long-working-distance microscope objective provided by the present invention has the following beneficial effects: The microscope objective lens of the present invention works in a wide band, covering the 436-700nm white light band and the 1400-1600nm infrared band. When the dual bands work simultaneously, there is no need for repeated focusing, thus avoiding the time delay and positioning error problems caused by conversion, reducing the dependence on the professional skills of the operator, and reducing the potential damage to samples such as embryos.

[0017] The present invention selects specific optical glass and plastic materials, such as the flat lens L9 adopts high thermal stability, high corrosion resistance high borosilicate PYREX7740 optical glass, the flat lens L10 adopts high transmittance, high mechanical strength, low Abbe number polycarbonate (PC) optical plastic, and performs reasonable lens combination design, thereby effectively eliminating the spherical aberration and dispersion generated by the composite cover glass material and improving the imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic structural diagram of a preferred embodiment of a 40-fold wide-band long-working-distance microscope objective lens provided by the present invention; Figure 2 It is a schematic diagram of the planar structure of a 40-fold wideband microscope objective lens; Figure 3 This is the axial chromatic aberration diagram of the 40x wideband microscope objective; Figure 4 This is the field curvature astigmatism diagram of a 40x wideband microscope objective; Figure 5 This is the distortion diagram of the 40x wideband microscope objective; Figure 6 This is the white light transfer function diagram of the 40x wideband microscope objective; Figure 7 This is the PSF diagram of the near-infrared 1480nm spectrum line of the 40x wideband microscope objective; Figure 8This is the transmittance curve of the 40x wideband microscope objective in the 436-1550nm band. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0020] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0021] Implementation 1 The embodiment of the present invention provides a 40-fold wideband long working distance microscope objective lens, which comprises: a cemented lens group G1, a cemented lens group G2, a cemented lens group G3, a lens group G4, a lens group G5, and a cemented lens group G6 arranged in sequence along the optical axis from the image direction to the object side; wherein the cemented lens group G1 is located on one side of the cemented lens group G2, the cemented lens group G3 is located on the side of the cemented lens group G2 away from the cemented lens group G1, the lens group G4 is located on the side of the cemented lens group G3 away from the cemented lens group G2, the lens group G5 is located on the side of the lens group G4 away from the cemented lens group G3, and the cemented lens group G6 is located on the side of the lens group G5 away from the lens group G4; the cemented lens group G1 is composed of a double concave negative lens L1 and a double convex positive lens L2 arranged in sequence along the optical axis from the image direction to the object side, and the cemented lens group G1 is composed of a double concave negative lens L1 and a double convex positive lens L2 arranged in sequence along the optical axis from the image direction to the object side, The cemented lens group G2 is composed of a meniscus negative lens L3 and a biconvex positive lens L4, which are arranged in sequence along the optical axis from the image direction to the object side, and the concave surface of the meniscus negative lens L3 faces the object side. The cemented lens group G3 is composed of a meniscus negative lens L5 and a biconvex positive lens L6, which are arranged in sequence along the optical axis from the image direction to the object side, and the concave surface of the meniscus negative lens L5 faces the object side; the lens group G4 includes a meniscus negative lens L7, and the meniscus negative lens L7 is located on the side of the biconvex positive lens L6 away from the meniscus negative lens L5, and the concave surface of the meniscus negative lens L7 faces the image side; the lens group G5 includes a meniscus positive lens L8, and the meniscus positive lens L8 is located on the side of the meniscus negative lens L7 away from the biconvex positive lens L6, and the convex surface of the meniscus positive lens L8 faces the image side; the cemented lens group G6 is composed of a flat plate lens L9 and a flat plate lens L10, which are arranged in sequence along the optical axis from the object direction to the image side, and are cemented.

[0022] Furthermore, the double concave negative lens L1, the double convex positive lens L2, the meniscus negative lens L7, and the meniscus positive lens L8 all adopt lanthanum optical glass with high refractive index and high transmittance in the infrared band to enhance the ability of eliminating spherical aberration.

[0023] Furthermore, the biconvex positive lens L4 and the biconvex positive lens L6 are both made of phosphate crown optical glass with high refractive index, high Abbe number, and high transmittance in the infrared band, so as to enhance the achromatic and apochromatic capabilities and improve the imaging quality.

[0024] Furthermore, the meniscus negative lens L3 is made of heavy flint optical glass with high refractive index and low Abbe number, which further improves the transmittance in the visible to near-infrared band.

[0025] Furthermore, the meniscus negative lens L5 is made of light flint optical glass with medium refractive index and high Abbe number, which further improves the achromatic ability.

[0026] Furthermore, the plano lens L9 is made of high borosilicate PYREX7740 optical glass with high thermal stability and high corrosion resistance, and the thickness is 0.7 mm.

[0027] Furthermore, the plano lens L10 is made of polycarbonate (PC) optical plastic with high transmittance, relatively high mechanical strength, and low Abbe number, and the thickness is 0.5 mm.

[0028] Furthermore, the focal length fG1 of the cemented lens group G1 satisfies: -85 mm < fG1 < -75 mm, the focal length fG2 of the cemented lens group G2 satisfies: 30 mm < fG2 < 40 mm, the focal length fG3 of the cemented lens group G3 satisfies: 15 mm < fG3 < 25 mm, the focal length fL7 of the meniscus negative lens L7 satisfies: -25 mm < fL7 < -15 mm, the focal length fL8 of the meniscus positive lens L8 satisfies: 7 mm < fL8 < 11 mm, the combined focal length fT2 of the lens groups G2, G3, and G4 and the focal length of the entire 40x wide-band microscopic objective lens satisfy: 4 < fT2 / fobj < 8, and the focal length fT3 of the lens group T3 and the focal length of the entire 40x wide-band microscopic objective lens satisfy: 1.4 < fT2 / fobj < 2.2.

[0029] A 40x wide-band microscopic objective lens uses wavelengths of 436 - 700 nm and 1400 - 1600 nm, and the specific parameters are as follows: Magnification: β = 40; Focal length: fobj = 5 mm; Object field of view: not less than diameter φ0.55 mm; Numerical aperture: NA = 0.5; Working distance: W.D = 3.02 mm.

[0030] Embodiment 2 A 40-fold wideband microscope objective lens comprises a biconcave negative lens L1, a biconvex positive lens L2, an aperture, a meniscus negative lens L3, a biconvex positive lens L4, a meniscus negative lens L5, a biconvex positive lens L6, a meniscus negative lens L7, a meniscus positive lens L8, a flat glass L9 and a flat plastic L10, which are arranged in sequence along an optical axis from an image direction to an object side; the biconcave negative lens L1 and the biconvex positive lens L2 are glued together to form a glued lens group G1, the meniscus negative lens L3 and the biconvex positive lens L4 are glued together to form a glued lens group G2, and the meniscus negative lens L5 and the biconvex positive lens L6 are glued together to form a glued lens group G3.

[0031] Furthermore, the double concave negative lens L1, the double convex positive lens L2, the meniscus negative lens L7, and the meniscus positive lens L8 all use lanthanum optical glass with high refractive index and high transmittance in the infrared band to enhance the ability to eliminate spherical aberration.

[0032] Furthermore, the double convex positive lens L4 and the double convex positive lens L6 both use phosphorus crown optical glass with high refractive index, high Abbe number and high transmittance in the infrared band to enhance the achromatic and apochromatic capabilities and improve the imaging quality.

[0033] Furthermore, the meniscus negative lens L3 adopts heavy flint optical glass with high refractive index and low Abbe number, which further improves the transmittance in the visible light to near-infrared band.

[0034] Furthermore, the flat lens L9 adopts high thermal stability, high corrosion resistance, high borosilicate PYREX7740 optical glass with a thickness of 0.7mm, and is a constant temperature hot plate for use in the biomedical field.

[0035] Furthermore, the flat lens L10 is made of polycarbonate (PC) optical plastic with high transmittance, high mechanical strength and low Abbe number, with a thickness of 0.5 mm, and is a culture dish for use in the biomedical field.

[0036] Furthermore, the focal length fL1 of the biconcave negative lens L1 satisfies: -6mm <fL1<-3mm。

[0037] Furthermore, the focal length fL2 of the biconvex positive lens L2 satisfies: 6 <fL2<10mm。

[0038] Furthermore, the focal length fL3 of the meniscus negative lens L3 satisfies: -20 mm <fL3<-13mm。

[0039] Furthermore, the focal length fL4 of the biconvex positive lens L4 satisfies: 9 mm <fL4<15mm。

[0040] Furthermore, the focal length fL5 of the meniscus negative lens L5 satisfies: -15mm <fL5<-9mm。

[0041] Furthermore, the focal length fL6 of the biconvex positive lens L6 satisfies: 6 mm <fL6<10mm。

[0042] Furthermore, the focal length fL7 of the meniscus negative lens L7 satisfies: -25mm <fL7<-15mm。

[0043] Furthermore, the focal length fL8 of the meniscus positive lens L8 satisfies: 7 mm <fL8<11mm。

[0044] Furthermore, the thickness DL9 of the flat glass L9 satisfies: 0.3 mm <DL9<0.7mm。

[0045] Furthermore, the thickness DL10 of the flat plastic L10 satisfies: 0.5 mm <DL10<1.0mm。

[0046] A 40x wideband microscope objective lens, using wavelengths of 436-700nm, 1400-1600nm, the specific parameters are as follows: Magnification: β=40; focal length: fobj=5mm; object field of view: φ0.55mm; numerical aperture: NA=0.5; working distance: WD=3.02mm; Furthermore, the focal length fA of the cemented lens group G1 satisfies: -85 mm <fG1<-75mm。

[0047] Furthermore, the focal length fB of the cemented lens group G2 satisfies: 30 mm <fG2<40mm。

[0048] Furthermore, the focal length fC of the cemented lens group G3 satisfies: 15 mm <fG3<25mm。

[0049] Furthermore, the combined focal length fT2 of the lens groups G2, G3, and G4 and the focal length of the entire 40x wideband microscope objective lens satisfy: 4<fT2 / fobj<8.

[0050] Furthermore, the focal length fT3 of the lens group T3 and the focal length of the entire 40x wideband microscope objective lens satisfy: 1.4<fT2 / fobj<2.2.

[0051] The invention has the characteristics of wide band, long working distance, high infrared transmittance, etc. The wavelength of white light is 436-700nm; the wavelength of infrared is 1400-1600nm; the focus shift of all spectral lines of white light is less than 1 / 2 focal depth of infrared wavelength, and there is no need to repeat focusing when dual bands work simultaneously.

[0052] The lens distribution and detailed parameters of this embodiment are shown in the following table:

[0053] Among them, the radius refers to the radius of curvature of the surface, and the thickness refers to the axial distance from the current surface to the next surface. For example, the thickness of surface S1 is the distance from S1 to S2, which may be the axial thickness of the medium or lens, or the axial air gap between them.

[0054] Figure 2 The figure shows the MTF contrast of imaging in the 436-700nm band. The horizontal axis represents the spatial frequency and the vertical axis represents the normalized contrast. It can be seen from the figure that the MTF contrast of most fields of view is good at each spatial frequency.

[0055] Figure 3 Displays axial chromatic aberration, with the minimum unit of the horizontal axis being 0.002um and the vertical axis representing the aperture. The figure shows that the maximum focus shift on the axis is <0.5um.

[0056] Figure 4 Display field curvature, the horizontal axis represents field curvature, the minimum unit is 0.005um, and the vertical axis represents field of view. The figure shows that the axial difference between the focus point of the edge field of view and the center field of view is small, which meets the clarity of the entire field of view and meets the requirements of a flat-field objective.

[0057] Figure 5 Display distortion, the horizontal axis represents the distortion percentage, the minimum unit is 0.2%, and the vertical axis represents the field of view. The figure shows that the maximum distortion of the entire field of view is <1%.

[0058] Figure 6 Displays the wavefront error. This figure is the wavefront diagram of the central field of view of the 632nm spectrum line, and its RMS is less than 0.1λ.

[0059] Figure 7 The Huygens PSF is displayed. The Strehl ratio of the central field of view of the 1480nm spectral line is 0.94, and the aberration correction is good.

[0060] Figure 8 This is a transmittance simulation diagram of each spectral line of the 40-fold wideband microscope objective lens in the 436-1600nm band. It can be seen from the figure that the transmittance in the 436-700nm band is greater than 90%, and the transmittance in the 1400-1600nm band is greater than 70%.

[0061] Example 3 A 40-fold wideband microscope objective lens comprises a biconcave negative lens L1, a biconvex positive lens L2, an aperture, a meniscus negative lens L3, a biconvex positive lens L4, a meniscus negative lens L5, a biconvex positive lens L6, a meniscus negative lens L7, a meniscus positive lens L8, a flat glass L9 and a flat plastic L10, which are sequentially arranged along an optical axis in an image direction and an object side. The biconcave negative lens L1 and the biconvex positive lens L2 are glued together to form a glued lens group G1, the meniscus negative lens L3 and the biconvex positive lens L4 are glued together to form a glued lens group G2, and the meniscus negative lens L5 and the biconvex positive lens L6 are glued together to form a glued lens group G3.

[0062] Furthermore, the double concave negative lens L1, the double convex positive lens L2, the meniscus negative lens L7, and the meniscus positive lens L8 all use lanthanum optical glass with high refractive index and high transmittance in the infrared band to enhance the ability to eliminate spherical aberration.

[0063] Furthermore, the double convex positive lens L4 and the double convex positive lens L6 both use phosphorus crown optical glass with high refractive index, high Abbe number and high transmittance in the infrared band to enhance the achromatic and apochromatic capabilities and improve the imaging quality.

[0064] Furthermore, the meniscus negative lens L3 adopts heavy flint optical glass with high refractive index and low Abbe number, which further improves the transmittance in the visible light to near-infrared band.

[0065] Furthermore, the flat lens L9 adopts high thermal stability, high corrosion resistance, high borosilicate PYREX7740 optical glass with a thickness of 0.7mm, and is a constant temperature glass hot plate for use in the biomedical field.

[0066] Furthermore, the flat lens L10 is made of polycarbonate (PC) optical plastic with high transmittance, high mechanical strength and low Abbe number, with a thickness of 0.5 mm, and is a culture dish for use in the biomedical field.

[0067] Furthermore, the focal length fL1 of the biconcave negative lens L1 satisfies: -6mm <fL1<-3mm。

[0068] Furthermore, the focal length fL2 of the biconvex positive lens L2 satisfies: 5 <fL2<9mm。

[0069] Furthermore, the focal length fL3 of the meniscus negative lens L3 satisfies: -15 mm <fL3<-9mm。

[0070] Furthermore, the focal length fL4 of the biconvex positive lens L4 satisfies: 8 mm <fL4<13mm。

[0071] Furthermore, the focal length fL5 of the meniscus negative lens L5 satisfies: -18 mm <fL5<-13mm。

[0072] Furthermore, the focal length fL6 of the biconvex positive lens L6 satisfies: 5 mm <fL6<9mm。

[0073] Furthermore, the focal length fL7 of the meniscus negative lens L7 satisfies: -17 mm <fL7<-11mm。

[0074] Furthermore, the focal length fL8 of the meniscus positive lens L8 satisfies: 5 mm <fL8<10mm。

[0075] Furthermore, the thickness DL9 of the flat glass L9 satisfies: 0.3 mm <DL9<0.7mm。

[0076] Furthermore, the thickness DL10 of the flat plastic L10 satisfies: 0.5 mm <DL10<1.0mm。

[0077] A 40x wideband microscope objective lens, using wavelengths of 436-700nm, 1400-1600nm, the specific parameters are as follows: Magnification: β=40; focal length: fobj=5mm; object field of view: φ0.55mm; numerical aperture: NA=0.5; working distance: WD=3.02mm.

[0078] Furthermore, the focal length fA of the cemented lens group G1 satisfies: -40 mm <fG1<-65mm。

[0079] Furthermore, the focal length fB of the cemented lens group G2 satisfies: 45 mm <fG2<65mm。

[0080] Furthermore, the focal length fC of the cemented lens group G3 satisfies: 9 mm <fG3<18mm。

[0081] Furthermore, the combined focal length fT2 of the lens groups G2, G3, and G4 and the focal length of the entire 40x wideband microscope objective lens satisfy the following relationship: 1.2<fT2 / fobj<1.8.

[0082] Furthermore, the focal length fT3 of the lens group T3 and the focal length of the entire 40x wideband microscope objective lens satisfy: 1<fT2 / fobj<2.

[0083] The invention has the characteristics of wide band, long working distance, high infrared transmittance, etc. The wavelength of white light is 436-700nm; the wavelength of infrared is 1400-1600nm; the focus shift of all spectral lines of white light is less than 1 / 2 focal depth of infrared wavelength, and there is no need to repeat focusing when dual bands work simultaneously.

[0084] The lens distribution and detailed parameters of this embodiment are shown in the following table:

[0085] Among them, the radius refers to the radius of curvature of the surface, and the thickness refers to the axial distance from the current surface to the next surface. For example, the thickness of surface S1 is the distance from S1 to S2, which may be the axial thickness of the medium or lens, or the axial air gap between them.

[0086] Figure 2The figure shows the MTF contrast of imaging in the 436-700nm band. The horizontal axis represents the spatial frequency and the vertical axis represents the normalized contrast. It can be seen from the figure that the MTF contrast of most fields of view is good at each spatial frequency.

[0087] Figure 3 Displays axial chromatic aberration, with the minimum unit of the horizontal axis being 0.002um and the vertical axis representing the aperture. The figure shows that the maximum focus shift on the axis is <0.5um.

[0088] Figure 4 Display field curvature, the horizontal axis represents field curvature, the minimum unit is 0.005um, and the vertical axis represents field of view. The figure shows that the axial difference between the focus point of the edge field of view and the center field of view is small, which meets the clarity of the entire field of view and meets the requirements of a flat-field objective.

[0089] Figure 5 Display distortion, the horizontal axis represents the distortion percentage, the minimum unit is 0.2%, and the vertical axis represents the field of view. The figure shows that the maximum distortion of the entire field of view is <1%.

[0090] Figure 6 Display wavefront error, the figure is the wavefront diagram of the central field of view of the 632nm spectrum line, its RMS is less than 0.1λ; Figure 7 Displays the Huygens PSF. The Strehl ratio of the central field of view of the 1480nm spectral line is 0.94, indicating good aberration correction. Figure 8 This is a transmittance simulation diagram of each spectral line of the 40-fold wideband microscope objective lens in the 436-1600nm band. It can be seen from the figure that the transmittance in the 436-700nm band is greater than 90%, and the transmittance in the 1400-1600nm band is greater than 70%.

[0091] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A 40-fold wide-band long working distance microscope objective lens, characterized in that: include: It consists of a cemented lens group G1, a cemented lens group G2, a cemented lens group G3, a lens group G4, a lens group G5, and a cemented lens group G6 which are arranged in sequence along the optical axis from the image direction to the object side; Wherein, the cemented lens group G1 is located on one side of the cemented lens group G2, the cemented lens group G3 is located on the side of the cemented lens group G2 away from the cemented lens group G1, the lens group G4 is located on the side of the cemented lens group G3 away from the cemented lens group G2, the lens group G5 is located on the side of the lens group G4 away from the cemented lens group G3, and the cemented lens group G6 is located on the side of the lens group G5 away from the lens group G4; The cemented lens group G1 is composed of a double concave negative lens L1 and a double convex positive lens L2 which are sequentially arranged along the optical axis from the image direction to the object side, and the cemented lens group G2 is composed of a meniscus negative lens L3 and a double convex positive lens L4 which are sequentially arranged along the optical axis from the image direction to the object side, and the concave surface of the meniscus negative lens L3 faces the object side, and the cemented lens group G3 is composed of a meniscus negative lens L5 and a double convex positive lens L6 which are sequentially arranged along the optical axis from the image direction to the object side, and the concave surface of the meniscus negative lens L5 faces the object side; The lens group G4 includes a meniscus negative lens L7, and the meniscus negative lens L7 is located on a side of the biconvex positive lens L6 away from the meniscus negative lens L5, and the concave surface of the meniscus negative lens L7 faces the image side; The lens group G5 includes a meniscus positive lens L8, and the meniscus positive lens L8 is located on a side of the meniscus negative lens L7 away from the double convex positive lens L6, and the convex surface of the meniscus positive lens L8 faces the image side; The cemented lens group G6 is composed of a flat plate lens L9 and a flat plate lens L10 which are sequentially arranged along the optical axis from the object direction to the image side and cemented together.

2. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The biconcave negative lens L1, the biconvex positive lens L2, the meniscus negative lens L7, and the meniscus positive lens L8 are all made of lanthanum optical glass.

3. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The biconvex positive lens L4 and the biconvex positive lens L6 are both made of phosphorus crown optical glass.

4. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The meniscus negative lens L3 is made of heavy flint optical glass.

5. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The meniscus negative lens L5 is made of light flint optical glass.

6. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The flat lens L9 is made of optical glass.

7. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The flat lens L10 is made of optical plastic.

8. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The focal length of the cemented lens group G1 is fG1, the focal length of the cemented lens group G2 is fG2, and the focal length of the cemented lens group G3 is fG3, and they satisfy the conditional formula: -85 mm <fG1<-75mm,30mm<fG2<40mm,15mm<fG3<25mm。 9. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The focal length of the meniscus negative lens L7 is fL7, which satisfies the condition: -25 mm <fL7<-15mm。 10. The 40-fold wideband long working distance microscope objective lens according to claim 1, characterized in that: The focal length of the meniscus positive lens L8 is fL8, which satisfies the condition: 7 mm <fL8<11mm。

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