Adjusting device and adjusting method for annular illumination of microscopic system

Abstract

The invention discloses an adjusting device and an adjusting method for annular illumination of a microscopic system, the adjusting device comprises a light source, and also comprises a collimating lens group, a monochromator, a polarizer, a zoom collimating lens group and a zoom conical lens group, the light source emits measuring light, the measuring light is coupled to the collimating lens group through an optical fiber, and the measuring light is collimated to the monochromator through the collimating lens group to form light with a specific wavelength; the light with the specific wave band selects a proper polarization state through the polarizer to form light with a certain polarization state and a specific wavelength, and the light with the certain polarization state and the specific wavelength is amplified or shrunk through the zoom collimating lens group and then enters the zoom conical lens group; annular illumination with adjustable inner and outer diameters is realized; compared with the prior art, different illumination sizes of the annular light beam can be adjusted and controlled, and the influence of ambient light on the system can be better overcome; and the focal length of the optical system can be adjusted by linearly moving the zoom lens group back and forth.

Description

Technical Field

[0001] The invention relates to the field of semiconductor wafer processing process detection lighting, and in particular to an adjustment device and an adjustment method for annular lighting of a microscope system. Background Art

[0002] Spatial light modulator (SLM) refers to the process of actively controlling a parameter of a light field by modulating liquid crystal molecules to write certain information into a light wave, thereby achieving the purpose of light wave modulation. It can load information into a one-dimensional or two-dimensional light field, and use the wide bandwidth of light and multi-channel parallel processing to quickly process the loaded information. Under the control of a time-varying electrical drive signal or other signal, the amplitude or intensity, phase, polarization state, and wavelength of the light distribution in space are changed. At present, the Industrial Technology Research Institute of Taiwan and Shanghai Microelectronics use air conditioning light modulators. The Industrial Technology Research Institute of Taiwan uses a holographic LC-R2500 spatial light modulator (SLM) to adjust the annular illumination of the light source, based on a reflective LCOS microdisplay with a resolution of 1024*768 pixels and an active area size of 9.5mmx14.6mm. The advantages of using LC-R2500 are high flexibility, high programmability, and real-time performance. It can realize fast modulation of the phase of light waves, adapt to complex optical transmission and processing, realize different phase modulation modes through programming control, and have customization and flexibility; the modulation of light waves is completed within milliseconds. The disadvantages of spatial light modulator (SLM) are: the use of optical holographic method to make filters is complex and not real-time, which will affect the timeliness of the recognition system and requires precise control circuits and algorithm support. SLM is sensitive to factors such as light and temperature in the external environment and is easily interfered with. In addition, the electrically addressed spatial light modulator transmits information through strip motors. There is a limit to the reduction of motor size, so the pixel size is limited. The motor itself is not transparent, so the ratio of the effective light-transmitting area of ​​the pixel to the total area of ​​the pixel is low, that is, the light energy utilization rate is relatively low.

[0003] The State Key Laboratory of Digital Manufacturing Equipment and Technology at Huazhong University of Science and Technology uses an annular diaphragm to achieve annular lighting by blocking the light in the center and the periphery. The light energy utilization rate is relatively low, and many annular diaphragms of different sizes need to be produced and replaced one by one each time, resulting in low work efficiency. Summary of the invention

[0004] The purpose of the present invention is to address the shortcomings of the prior art, in which a spatial light modulator made by an optical holographic method is relatively complex and not real-time, which will affect the timeliness of the recognition system and require precise control circuits and algorithm support; the electrically addressed spatial light modulator has a relatively low light energy utilization rate; the spatial light modulator that uses an annular aperture to block the light from the center and the periphery has a relatively low light energy utilization rate and needs to make many annular apertures of different sizes, which need to be replaced one by one each time, resulting in low work efficiency. In view of the shortcomings of the spatial light modulators with different working principles mentioned above, an adjustment device and an adjustment method for annular illumination of a microscope system are proposed.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A regulating device for annular illumination of a microscope system comprises a light source, a collimator lens group, a monochromator, a polarizer, a zoom collimator lens group, and a variable magnification conical lens group.

[0007] Among them, the light source emits measurement light, which is coupled to the collimator group through the optical fiber, and is collimated to the monochromator through the collimator group to form light of a specific wavelength. The light of the specific band then selects a suitable polarization state through the polarizer to form light of a specific wavelength with a certain polarization state. The light of a specific wavelength with a certain polarization state is magnified or reduced by the zoom collimator group, and then enters the variable magnification conical mirror group to realize annular illumination with adjustable inner and outer diameters.

[0008] As a further preferred embodiment of the present invention, the collimator lens is a combination of a quartz lens and a silicon fluoride lens; the wavelength of 200-1600nm is available, and the collimator lens group is designed and optimized to minimize aberration and chromatic aberration, that is, to eliminate off-axis spherical aberration and chromatic aberration.

[0009] As a further preferred embodiment of the present invention, the polarizer includes a quartz glass substrate, a metal wire array disposed in the quartz glass substrate, which forms a metal wire grid polarizer, and a protective glass covering the metal wire array. The top surface and the bottom surface of the protective glass and the bottom surface of the quartz glass substrate are coated with an anti-reflection film. The metal wire grid polarizer has high transmittance and a high maximum operating temperature, and can replace traditional thin-film polarizers and holographic wire grid polarizers. The metal wire grid polarizer is coated with an anti-reflection film of 200-1600nm on the back of the substrate and both sides of the protective glass, and the maximum extinction ratio can reach 10,000:1.

[0010] As a further preferred embodiment of the present invention, the zoom collimating lens group includes a fixed lens group, a zoom lens group and a compensating lens group, which are sequentially arranged along the optical path.

[0011] As a further preferred embodiment of the present invention, the zoom lens group is composed of a plurality of lenses, and the zoom lens group moves linearly back and forth between the fixed lens group and the compensating lens group, parallel light is incident on the fixed lens group, and the outgoing light from the compensating lens group is still parallel light; the zoom collimating lens group changes the focal length of the optical system by linearly moving the zoom lens group back and forth.

[0012] As a further preferred embodiment of the present invention, the compensation lens group is composed of a plurality of lenses, and the compensation lens group performs nonlinear linear motion according to Δy, and the compensation lens group causes the entire image plane to shift during the movement;

[0013]

[0014] Δy is the movement amount of the compensation lens group, x is the focal length of the zoom lens group, and F2 is the focal length of the ideal zoom lens group, which is a positive optical power.

[0015] As a further preferred embodiment of the present invention, based on the incident parallel light diameter d0, the focal length F1 of the fixed lens group and the focal length F2 of the zoom lens group, the exit spot diameter d of the compensation lens group is calculated.

[0016]

[0017] As a further preferred embodiment of the present invention, the variable-power conical lens group is composed of a pair of convex-concave conical lenses or a pair of convex-conical lenses of the same specifications. By changing the vertex spacing between the two conical lenses, the inner and outer diameters of the ring width in the annular lighting mode can be adjusted while the ring width remains unchanged.

[0018] As a further preferred embodiment of the present invention, the included angles of a pair of convex-conical lenses or a pair of convex-conical lenses of the same specification are the same.

[0019] A method for adjusting an adjusting device for annular illumination of a microscope system, comprising the following steps:

[0020] S1, setting two ideal lens groups with focal length F1 as a fixed lens group and a compensating lens group;

[0021] The ideal lens group with a focal length of F2 is a zoom lens group;

[0022] S2, setting the incident parallel light diameter to d0 and the movement amount of the zoom lens group to Δx;

[0023] S3, based on the focal length F2 of the zoom lens group and the movement amount Δx of the zoom lens group,

[0024] The focal distance x of the zoom lens assembly is obtained by x=2F2+Δx;

[0025] S4, based on the focal length F2 of the zoom lens group and the focal object distance x of the zoom lens group,

[0026] pass The nonlinear linear motion Δy of the compensation mirror group is obtained;

[0027] S5, based on the focal length F2 of the zoom lens group, the movement amount Δx of the zoom lens group, the focal length F1 of the fixed lens group, and the incident parallel light diameter d0,

[0028] pass Obtain the clear aperture d1 of the zoom lens group;

[0029] S6, based on the focal length F2 of the zoom lens group, the focal length F1 of the fixed lens group, and the incident parallel light diameter d0,

[0030] pass Get the exit spot diameter d;

[0031] S7, optimizing the aberration caused by the movement of the zoom lens group by adjusting the moving distance Δx of the zoom lens group and the moving distance Δy of the compensation lens group, so as to achieve adjustable focal length of the optical system;

[0032] S8. By adjusting the vertex distance between the two conical lenses in the variable-magnification conical lens group, the inner and outer diameter sizes of the ring width in the ring lighting mode are achieved, and the ring width is kept unchanged.

[0033] The present invention provides an adjustment device and an adjustment method for annular illumination of a microscope system, which have the following beneficial effects compared with the prior art:

[0034] 1. The optical path of the present invention is simple, low in cost, and easy to install;

[0035] 2. In the beam shaping system adopted by the present invention, all light is utilized without any obstruction or interception, which effectively improves the utilization rate of light energy;

[0036] 3. The device and method of the present invention can realize the adjustment and control of different lighting sizes of the annular light beam, and can better overcome the influence of ambient light on the system;

[0037] 4. The focal length of the optical system can be adjusted by moving the zoom lens group linearly forward and backward;

[0038] 5. Compensate for the aberration introduced by the forward and backward movement of the zoom lens group by moving the compensation lens group nonlinearly;

[0039] 6. The inner and outer diameters of the annular illumination are adjusted by adjusting the vertex distance between the two conical mirrors of the variable magnification conical mirror group, and the difference between the outer diameter and the inner diameter of the annular illumination remains unchanged. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of a first embodiment of an adjustment device for annular illumination of a microscope system according to the present invention;

[0041] Figure 2 is a schematic diagram of a second embodiment of an adjustment device for annular illumination of a microscope system according to the present invention;

[0042] Figure 3 is a schematic diagram of the structure of a metal wire grid polarizer;

[0043] Figure 4 is a graph showing the relationship between the movement amount Δx of the zoom lens group and the movement amount Δy of the compensation lens group;

[0044] Figure 5 is a graph showing the relationship between the movement amount Δx of the zoom lens group and the output spot size d;

[0045] Figure 6 It is the output light spot diagram corresponding to different L1 in the zoom collimator group;

[0046] Figure 7 is a curve showing the relationship between the vertex distance L0 of the convex-conical lens and the inner and outer diameters of the light spot in the first embodiment;

[0047] Figure 8 Graph showing the relationship between the vertex distance L0' of a pair of convex conical lenses and the inner and outer diameters of the light spot in the second embodiment.

[0048] The meanings of the reference numerals in the figure are: 1. light source, 2. collimator lens group, 3. monochromator, 4. polarizer, 5. zoom collimator lens group, 6. variable magnification conical lens group, 7. fixed lens group, 8. zoom lens group, 9. compensation lens group, 10. first conical lens, 11. second conical lens, 12. initial circular illumination, 13. adjustable annular illumination, 14. quartz glass substrate, 15. metal wire array, 16. protective glass, 17. anti-reflection film. DETAILED DESCRIPTION

[0049] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] The microscopic system annular illumination adjustment method and technology of the present invention are mainly used in semiconductor wafer processing process detection illumination system. At present, the illumination system in the semiconductor wafer processing process error detection equipment uses a spatial light modulator (SLM) to control the illumination mode and annular aperture. Compared with the method in which the annular aperture blocks the light in the center and the peripheral part to realize annular illumination, in the beam shaping system used in the present invention, all the light is used without blocking and intercepting, which can effectively improve the utilization rate of light energy.

[0051] The present invention discloses a method for adjusting annular illumination of a microscope system, which uses a combination of a zoom collimator lens group 52 (Zoom) and a variable-power conical lens group 6 (Axicon) to adjust the inner diameter and outer diameter of the annular illumination. The present invention provides an adjusting device and an adjusting method for annular illumination of a microscope system, which can overcome the technical problems of the complexity of the SLM in the prior art, the strong sensitivity to factors such as light and temperature in the external environment, and the low working efficiency of the annular apertures that need to be replaced one by one each time, and achieve the measurement accuracy requirements and a simple and cheap implementation measurement solution.

[0052] Embodiment 1: Combination Figure 1-2 , an adjusting device for annular illumination of a microscope system, comprising a light source 1, a collimator lens group 2, a monochromator 3, a polarizer 4, a zoom collimator lens group 52, and a variable magnification conical lens group 6,

[0053] Among them, the light source 1 emits a measuring light, which is coupled to the collimating lens group 2 through the optical fiber, and is collimated to the monochromator 3 through the collimating lens group 2 to form a light of a specific wavelength. The light of the specific band then selects a suitable polarization state through the polarizer 4 to form a light of a specific wavelength with a certain polarization state. The light of the specific wavelength with a certain polarization state is magnified or reduced by the zoom collimating lens group 52, and then enters the variable magnification conical lens group 6 to realize annular illumination with adjustable inner and outer diameters.

[0054] The collimator lens is a combination of a quartz lens and a silicon fluoride lens; the wavelength of 200-1600nm is available, and the collimator lens group 2 is designed and optimized to minimize aberration and chromatic aberration, that is, to eliminate off-axis spherical aberration and chromatic aberration.

[0055] Polarizer 4 refers to a device for obtaining polarized light from natural light emitted by ordinary light source 1, and polarization is achieved by selectively absorbing or reflecting the vibration direction of light waves. The polarizer 4 includes a quartz glass substrate 14, a metal wire array 15 arranged in the quartz glass substrate 14, which forms a metal wire grid polarizer, and a protective glass 16 covering the metal wire array 15. The top surface and the ground of the protective glass and the ground of the quartz glass substrate 14 are coated with an anti-reflection film 17; the metal wire grid polarizer has high transmittance and a high maximum operating temperature, and can replace traditional thin-film polarizers and holographic wire grid polarizers. The metal wire grid polarizer is coated with a 200-1600nm anti-reflection film 17 on the back of the substrate and both sides of the protective glass 16, and the maximum extinction ratio can reach 10,000:1.

[0056] The monochromator 3 is a spectroscopic instrument suitable for generating monochromatic light, and for separating and selecting monochromatic light in a spectrum. It can separate a wide-band radiation beam into a series of narrow-band electromagnetic radiation, and output a series of monochromatic light with sufficiently narrow spectral intervals. The monochromator 3 is composed of a prism or a grating, and the wavelength of the output monochromatic light can be continuously adjusted as needed.

[0057] The zoom collimator lens group 52 includes a fixed lens group 7, a zoom lens group 8 and a compensating lens group 9, and they are arranged in sequence along the optical path. The zoom lens group 8 is composed of a plurality of lenses, and the zoom lens group 8 moves linearly back and forth between the fixed lens group 7 and the compensating lens group 9. Parallel light is incident on the fixed lens group 7, and the light emitted from the compensating lens group 9 is still parallel light; the zoom collimator lens group 52 changes the focal length of the optical system by linearly moving the zoom lens group 8 back and forth. The compensating lens group 9 is composed of a plurality of lenses, and the compensating lens group 9 performs nonlinear linear motion according to Δy. The compensating lens group 9 affects the overall image plane to shift during the movement.

[0058] The ideal lens group with a focal length of F1 is a fixed lens group 7 with negative focal power.

[0059] The ideal lens group with a focal length of F2 is zoom lens group 8, positive focal power,

[0060] The ideal lens group with a focal length of F1 is the compensation lens group 9.

[0061] The initial structure is set to a magnification of 1x, then the distance A between the fixed lens group 7 and the zoom lens group 8 is 2F2-F1, the distance B between the compensation lens group 9 and the zoom lens group 8 is 2F2-F1, the incident parallel light diameter is set to d0, the aperture of the zoom lens group 8 is d1, the diameter of the outgoing light is d, the zoom lens group 8 moves linearly, the movement amount is Δx, and the movement amount of the compensation lens group 9 is Δy.

[0062] The focal length of the zoom lens group 8 is: x=2F2+Δx;

[0063] The focal length of the zoom lens group 8 is: x′=2F2-Δx+Δy;

[0064] According to Newton's formula: x*x′=F2*F2,

[0065] Obtain: (2F2+Δx)*(2F2-Δx+Δy)=F2*F2

[0066] Calculated:

[0067] The compensating mirror group 9 performs nonlinear linear motion according to the Δy formula.

[0068] The aperture of the zoom lens group 8 is:

[0069] Finally, the exit spot diameter is obtained as:

[0070]

[0071] The variable-power conical lens group 6 is composed of a pair of convex-concave conical lenses or a pair of convex-conical lenses of the same specifications, and the angles of the pair of convex-concave conical lenses or the pair of convex-conical lenses of the same specifications are the same; by changing the vertex spacing between the two conical lenses, the inner and outer diameters of the ring width in the annular lighting mode can be adjusted, and the ring width remains unchanged.

[0072] Embodiment 2: A method for adjusting an adjusting device for annular illumination of a microscope system, comprising the following steps:

[0073] S1, setting two ideal lens groups with focal length F1 to be a fixed lens group 7 and a compensating lens group 9;

[0074] The ideal lens group with a focal length of F2 is zoom lens group 8;

[0075] S2, setting the incident parallel light diameter to d0 and the movement amount of the zoom lens group 8 to Δx;

[0076] S3, based on the focal length F2 of the zoom lens group 8 and the movement amount Δx of the zoom lens group 8,

[0077] The focal distance x of the zoom lens assembly 8 is obtained by x=2F2+Δx;

[0078] S4, based on the focal length F2 of the zoom lens group 8 and the focal object distance x of the zoom lens group 8,

[0079] pass The nonlinear linear motion Δy of the compensation mirror group 9 is obtained;

[0080] S5, based on the focal length F2 of the zoom lens group 8, the movement amount Δx of the zoom lens group 8, the focal length F1 of the fixed lens group 7, and the incident parallel light diameter d0,

[0081] pass Obtain the clear aperture d1 of the zoom lens group 8;

[0082] S6, based on the focal length F2 of the zoom lens group 8, the focal length F1 of the fixed lens group 7, and the incident parallel light diameter d0,

[0083] pass Get the exit spot diameter d;

[0084] S7, by adjusting the moving distance Δx of the zoom lens group 8 and the moving distance Δy of the compensation lens group 9, the aberration caused by the movement of the zoom lens group 8 is optimized, so as to realize the adjustable focal length of the optical system;

[0085] S8. By adjusting the vertex distance between the two conical lenses in the variable-power conical lens group 6, the inner and outer diameter sizes of the ring width in the ring illumination mode are achieved, and the ring width is kept unchanged.

[0086] Embodiment 3: In the first embodiment, the zoom collimator lens group 52 is composed of three optical modules, the first module is the fixed lens group 7, the second module is the zoom lens group 8, and the third module is the compensation lens group 9, which ensures that parallel light is incident on the fixed lens group 7, and the output light of the compensation lens group 9 is still parallel light. By moving the zoom lens group 8 and the compensation lens group 9 forward and backward, the system focal length is changed and the compensation lens group is shifted during the movement process. The input optical parameters are shown in Table 1 below:

[0087] Table 1 Input optical parameters of zoom collimator lens assembly 52

[0088] Radius of curvature Thickness / Air Gap Refractive Index Abbe number Fixed mirror set -32 3 1.458 67.821 32 20(L1) Zoom lens set 26 5 1.458 67.821 -26 21.74(L2) Compensating lens set. -32 3 1.458 67.821 32 10

[0089] The input parallel light diameter is d0=3mm, the output parallel light diameter is d, the moving distance of the zoom lens group is Δx, the moving distance of the compensation lens group 9 is Δy, the Δx value is changed, the Δy value is optimized, and the specific value of Δy and the output parallel light diameter d are obtained, as shown in Table 2:

[0090] Table 2 Data table of the movement amount Δx of the zoom lens group 8 and the movement amount Δy of the compensation lens group 9, the movement amount Δx of the zoom lens group 8 and the output spot size d

[0091] x / mm 0 1 2 3 5 8 10 12 15 20 25 y / mm O -0.045 -0.02 0.068 0.41 1.267 2.027 2.91 4.429 7.371 10.7 d / mm 3.044 3.144 3.244 3.346 3.546 3.846 4.046 4.244 4.544 5.044 5.544

[0092] The relationship curve between the movement amount Δx of the zoom lens group 8 and the movement amount Δy of the compensation lens group 9 is obtained from the data in Table 2, as shown in FIG. Figure 3 As shown in FIG. 1 , the relationship between the movement amount Δx of the zoom lens group 8 and the output spot size d is shown in FIG. Figure 4 As shown, according to Figure 3 By fitting, the relationship between the movement amount Δx of the zoom lens group 8 and the movement amount y of the compensation lens group 9 and the relationship between the movement amount Δx of the zoom lens group 8 and the output spot size d are obtained:

[0093] d = 0.1004Δx + 3.04,

[0094] y=0.0143Δx 2 +0.0835Δx-0.2008,

[0095] Axicon 6 (Axicon), an axicon is a conical prism defined by a vertex angle α. An axicon can focus light to multiple points on the optical axis. The light beam generated by the axicon passes through the optical axis. When the distance from the axicon to the image increases, the diameter of the light ring formed will also increase, while the thickness of the light ring remains unchanged. The beam has the characteristics of a Bessel beam, and the intensity distribution along the propagation direction of the beam will not change. The Bessel beam of the axicon is different from the Gaussian beam that diverges with distance. The Bessel beam is a non-diffraction beam that can maintain the intensity distribution unchanged during propagation.

[0096] According to the application requirements, after the parallel light enters the variable magnification conical lens group 6, it is also emitted as parallel light, so the first embodiment uses a concave cone lens and a convex cone lens, the α angle of the concave cone lens is the same as the α angle of the convex cone lens, and the diameter of the light ring is adjusted by controlling the distance between the two cone lenses. The DOF function includes the incident light radius (R) of the axicon lens, the refractive index (n) of the axicon lens, the α angle, and the radian value a:

[0097]

[0098] The thickness of the ring (t) remains constant and is easily determined; it is equal to the radius of the initial beam or half of the initial beam diameter d, and is constant as the distance between the axicons changes:

[0099]

[0100] The diameter of the light ring is proportional to the distance. As the distance (L0) from the output end of the concave cone lens to the positive cone lens increases, the diameter of the light ring (dr) will increase, and as the distance decreases, the diameter will also decrease. The outer diameter of the light ring is d gro_o , the inner diameter of the ring is d gro_i .

[0101]

[0102] d gro_o =d b +2L*tan[(n-1)a],

[0103] In the above formula, a is the radian value, which is 0.314 (i.e. 18°). The glass material of the axicon is quartz, with a refractive index of 1.4585. The initial beam diameter d = 8.6 mm. The outer diameter of the light ring at L0 = 10 mm is calculated as: d gro_o =2*10*tan[(1.4585-1)*0.314]+8.4=2*10*0.144+9.092=11.972mm,

[0104] Radius of curvature Thickness / Air Gap Refractive Index Abbe number Conic First Axis Infinity 4 1.458 67.821 -10 0.001 <![CDATA[10(L0)]]> Second Axis 0.001 4 1.458 67.821 -10 Infinity 30

[0105] By point series Figure 6 In (a), it can be seen that when L0 is 10 mm, the GEO radius is 5.96 mm and the diameter is about 11.92 mm, which is consistent with the calculation. gro_o and d gro_i Relationships, such as Figure 7 It can be seen from the above formula that when the variable-power conical lens group 6 is fixed, the different focal lengths of the zoom collimating lens group 52 do not affect the inner diameter of the light spot ring, but can change the outer diameter of the ring.

[0106] Embodiment 4: Since the processing of the concave cone lens is difficult and the processing cost is high, according to the above requirements, the second embodiment is further explained in detail.

[0107] The variable-power conical lens group 6 (Axicon) is matched with a pair of convex conical lenses of the same specification, and the angle of the conical lenses is α. The diameter of the light ring is adjusted by controlling the distance between the two conical lenses.

[0108] The diameter of the light ring is proportional to the distance. As the distance (L0) from the output end of the concave cone lens to the convex cone lens increases, the diameter of the light ring (dr) will increase, and as the distance decreases, the diameter will also decrease. The outer diameter of the light ring is d gro_o , the inner diameter of the ring is d gro_i .

[0109] The relationship is:

[0110] d gro_i =2L*tan[(n-1)a]-d b ,

[0111] d gro_o =2L*tan[(n-1)a],

[0112] d gro_o =d b +2L*tan[(n-1)a],

[0113] In the above formula, a is the radian value, which is 0.2617 (i.e. 15°). The glass material of the axicon is quartz, with a refractive index of 1.4585. The initial beam diameter d' = 10.11 mm. The outer diameter of the light ring at L0' = 50 mm is calculated as:

[0114] dgro _ o=2*50*tan[(1.4585-1)*0.2617]=2*50*0.1206=12.06mm,

[0115] Radius of curvature Thickness / Air Gap Refractive Index Abbe number Conic First Axis Infinity 4 1.458 67.821 -20 -0.001 <![CDATA[50(L0’)]]> Second Axis 0.001 4 1.458 67.821 -20 Infinity 30

[0116] By point series Figure 6In (b), it can be seen that when L0' is 50mm, the GEO radius is 6.24mm and the diameter is about 12.48mm, which is consistent with the calculation. gro_o ' and d gro_i 'Relationship, such as Figure 8 It can be seen from the above formula that when the variable-power conical lens group 6 is fixed, the different focal lengths of the zoom collimating lens group 52 do not affect the outer diameter of the light spot ring, but can change the inner diameter of the ring, which is opposite to the first implementation case.

[0117] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A regulating device for annular illumination of a microscope system, comprising a light source, characterized in that: It also includes a collimator lens group, a monochromator, a polarizer, a zoom collimator lens group, and a variable magnification conical lens group. Among them, the light source emits measurement light, which is coupled to the collimator group through the optical fiber, and is collimated to the monochromator through the collimator group to form light of a specific wavelength. The light of the specific band then selects a suitable polarization state through the polarizer to form light of a specific wavelength with a certain polarization state. The light of a specific wavelength with a certain polarization state is magnified or reduced by the zoom collimator group, and then enters the variable magnification conical mirror group to realize annular illumination with adjustable inner and outer diameters.

2. The adjusting device for annular illumination of a microscope system according to claim 1, characterized in that: The collimating mirror is a combination of a quartz lens and a silicon fluoride lens.

3. The adjusting device for annular illumination of a microscope system according to claim 1, characterized in that: The polarizer comprises a quartz glass substrate, a metal wire array arranged in the quartz glass substrate to form a metal wire grid polarizer, and a protective glass covering the metal wire array. The top surface and the ground surface of the protective glass and the ground surface of the quartz glass substrate are all coated with anti-reflection films.

4. The adjusting device for annular illumination of a microscope system according to claim 1, characterized in that: The zoom collimating lens group comprises a fixed lens group, a zoom lens group and a compensating lens group, which are arranged in sequence along the optical path.

5. The adjusting device for annular illumination of a microscope system according to claim 4, characterized in that: The zoom lens group is composed of a plurality of lenses, and the zoom lens group moves linearly back and forth between the fixed lens group and the compensation lens group.

6. The adjusting device for annular illumination of a microscope system according to claim 4, characterized in that: The compensation mirror group is composed of a plurality of lenses, and the compensation mirror group performs nonlinear linear motion according to Δy; Δy is the movement amount of the compensation lens group, x is the focal length of the zoom lens group, and F2 is the focal length of the ideal zoom lens group, which is a positive optical power.

7. The adjusting device for annular illumination of a microscope system according to claim 4, characterized in that: Based on the incident parallel light diameter d0, the focal length F1 of the fixed lens group and the focal length F2 of the zoom lens group, the exit spot diameter d of the compensation lens group is calculated.

8. The adjusting device for annular illumination of a microscope system according to claim 1, characterized in that: The variable-power conical lens group is composed of a pair of convex-concave conical lenses or a pair of convex-conical lenses of the same specification.

9. The adjusting device for annular illumination of a microscope system according to claim 8, characterized in that: The included angles of a pair of convex-conical lenses or a pair of convex-conical lenses of the same specification are the same.

10. A method for adjusting an adjusting device for annular illumination of a microscope system according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, setting two ideal lens groups with focal length F1 as a fixed lens group and a compensating lens group; The ideal lens group with a focal length of F2 is a zoom lens group; S2, setting the incident parallel light diameter to d0 and the movement amount of the zoom lens group to Δx; S3, based on the focal length F2 of the zoom lens group and the movement amount Δx of the zoom lens group, The focal distance x of the zoom lens assembly is obtained by x=2F2+Δx; S4, based on the focal length F2 of the zoom lens group and the focal object distance x of the zoom lens group, pass The nonlinear linear motion Δy of the compensation mirror group is obtained; S5, based on the focal length F2 of the zoom lens group, the movement amount Δx of the zoom lens group, the focal length F1 of the fixed lens group, and the incident parallel light diameter d0, pass Obtain the clear aperture d1 of the zoom lens group; S6, based on the focal length F2 of the zoom lens group, the focal length F1 of the fixed lens group, and the incident parallel light diameter d0, pass Get the exit spot diameter d; S7, optimizing the aberration caused by the movement of the zoom lens group by adjusting the moving distance Δx of the zoom lens group and the moving distance Δy of the compensation lens group, so as to achieve adjustable focal length of the optical system; S8. By adjusting the vertex distance between the two conical lenses in the variable-magnification conical lens group, the inner and outer diameter sizes of the ring width in the ring lighting mode are achieved, and the ring width is kept unchanged.

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