CN1327261C - An optical aspheric surface detection qausi-universal compensating mirror - Google Patents

Abstract

The present invention relates to a quasi-universal compensating lens for optical aspherical surface detection, which belongs to the technical field of optical aspherical surface detection. A universal compensating lens of an existing dual lens has the defects of larger volume, difficult fabrication, assembly and adjustment, only detection of aspherical surfaces with large paraxial radiuses, small variation range of eccentricity and low detection precision. The quasi-universal compensating lens of the present invention is composed of three spherical lenses which are arranged coaxially in sequence. The three spherical lenses are respectively a convex plano lens, a plano-concave lens and a biconvex lens. The curvature radiuses of the convex surface of the convex plano lens and the concave surface of the plano-concave lens are equal. The front focus of the convex plano lens is coincident with the rear focus of a standard spherical lens. Light between the convex plano lens and the plano-concave lens is parallel light. The initial position of the quasi-universal compensating lens is determined by utilizing the light adjustment correction and the positioning of plane surface reflection by an optical autocollimation method. The spherical aberration of the quasi-universal compensating lens is adjusted to be equal to the normal aberration of the detected aspherical surface. The defects of the prior art are overcome overall, and quadric and high order aspherical surfaces can be detected within a larger range on higher accuracy.

Description

A quasi-universal compensating mirror for optical aspheric surface detection

technical field

The invention belongs to the technical field of optical aspheric surface detection.

Background technique

The accuracy of its surface shape is detected by detecting optical aspheric wave aberration. In the prior art, the detection method related to the present invention is the interferogram method. The detection device used includes three parts: interferometer, standard spherical mirror and compensation mirror. , the interferometer generally uses a Tieman-Green interferometer, the light source is a helium-neon laser, and the laser with a wavelength of 632.8 nanometers is provided. When the compensation accuracy meets the Rayleigh criterion, that is, when the wave aberration is less than one-tenth of the wavelength, the obtained detection results can accurately reflect the accuracy of the tested aspheric surface. In such a device, the interferometer and the standard spherical mirror are common instruments and components, while the compensating mirror is an optical component specially designed for the detection of aspheric surfaces. The known compensating mirror was introduced by Priyaev of the Soviet Union in a book called "Optical Aspheric Surface Inspection" published by Science Publishing House (China) in 1982. One of them is called dual-lens universal compensation mirror, as shown in Figure 1, compensation mirror 1 is composed of two lenses, lens 2 is a meniscus lens with equal spherical radius, lens 3 is a biconvex lens, and the two are coaxial Placement with air space in between. The compensation mirror 1 is placed between the light source and the tested aspheric surface 4, and the three are coaxial. The laser light is reflected by the aspherical surface 4 to be inspected after passing through the compensation mirror 1 . The detection ability and effect of this detection device depend on the shape, structure and optical parameters of the compensating mirror 1 itself on the one hand, such as what kind and how many lenses the compensating mirror 1 consists of, the order of arrangement and the value of the distance _dn , each lens The radius of curvature r _n value of each surface, the thickness D _n value of each lens, and the thickness d value of the compensation mirror 1; on the other hand, it depends on the position of the compensation mirror 1 in the detection device, such as the distance from the compensation mirror 1 to its front focus O Distance-S ₀ value, the distance d ₀ value between the compensation mirror 1 and the tested aspheric surface 4. Through the adjustment of the above factors, the compensation mirror 1 can adapt to the detection of different types of aspheric surfaces, such as paraboloids, hyperboloids, ellipsoids and other quadratic surfaces of revolution and even high-order surfaces, and can also detect the paraxial radius r ₀ value and eccentricity e value , Every kind of curved surface whose caliber D value changes within a certain range, because of this, the inventor of this compensating mirror calls it a universal compensating mirror. When the wave aberration ΔW of the detection result is less than one-tenth of the wavelength, according to the Rayleigh criterion, the tested aspheric surface 4 meets the requirements for use.

Contents of the invention

The thickness of the lens 2 in the dual-lens universal compensating mirror 1 in the known technology reaches 141 millimeters, and the total weight of the compensating mirror reaches 5.655 kilograms, which is not easy to manufacture, and is inconvenient to assemble and use. Moreover, the detection range is limited to aspheric surfaces with large paraxial radius r ₀ , and the minimum r ₀ value is above 3440mm; and the range of eccentricity e corresponding to each paraxial radius r ₀ is very small, for example, hyperboloid paraxial radius r ₀ ranges from 14729.83mm to 6160.949mm, and its eccentricity e value is 1.4; moreover, the detection accuracy is not high, and the compensation accuracy of the aspheric surface is only 0.28-1.11 microns, that is, the wave aberration is only 0.4-1.7 wavelengths, This detection result does not meet the requirement of less than 0.1 wavelength of the Rayleigh criterion. In order to overcome the above-mentioned shortcomings of the known technology, we have invented a quasi-universal compensator for optical aspheric surface detection of the present invention.

The present invention is realized like this, see shown in Fig. 2, Fig. 3, the composition of optical aspheric surface detection quasi-universal compensating mirror 5 (hereinafter referred to as quasi-universal compensating mirror) of the present invention is, convex-flat spherical lens 6, plano-concave spherical lens 7, double-convex spherical lenses 8 are coaxially arranged in sequence, the radius of curvature r ₁ of the first surface of the convex-flat spherical lens 6 is equal to the radius of curvature r ₄ of the second surface of the flat-concave spherical lens 7, and the convex-flat spherical lens 6 is the first The radius of curvature r ₂ of two surfaces and the radius of curvature r ₃ of the first surface of the plano-concave spherical lens 7 are infinite, and the front focal point of the convex-flat spherical lens 6 coincides with the back focus F of the standard spherical mirror 10, and the convex-flat spherical lens 6 1. The light between the plano-concave spherical lenses 7 is parallel light, and the optical self-collimation method utilizes the light adjustment and positioning of plane reflection, so that the front focus O of the quasi-universal compensating mirror 5 coincides with the rear focus F of the standard spherical mirror. The point is also the position of the light source, and the distance between it and the quasi-universal compensating mirror 5 is -S ₀ , thereby determining the initial position of the quasi-universal compensating mirror 5, and the biconvex spherical lens 8 in the quasi-universal compensating mirror 5 compensates the convex-flat spherical lens 6. The high-level aberration of the plano-concave spherical lens 7 and the spherical aberration of the quasi-universal compensating mirror 5 are equal to the normal aberration of the tested aspheric surface 4.

When the quasi-universal compensating mirror 5 is used to detect the tested aspheric surface 4, the quasi-universal compensating mirror 5 is combined with the Teiman-Green interferometer 9 and the standard spherical mirror 10, as shown in Figure 3, Teiman-Green The parallel light beam of the test optical path of the interferometer 9 is focused on the rear focus F' after passing through the standard spherical mirror 10, and then after passing through the quasi-universal compensation mirror 5, its paraxial beam converges on the paraxial spherical center C of the tested aspheric surface 4, that is, the paraxial The light beam coincides with the normal of the tested aspheric surface 4; When testing other kinds of different aspheric surfaces, move the quasi-universal compensation mirror 5 to a certain position along the optical axis, so that the spherical aberration of the beam emitted by the quasi-universal compensation mirror 5 and the normal aberration of the tested aspheric surface 4 are compensated , the compensation accuracy satisfies the Rayleigh criterion, that is, the wave aberration ΔW of the detection result is less than one-tenth of the wavelength. The quasi-universal compensating mirror 5 can electrically detect various convex aspheric surfaces, and the principle and device are the same, only the convex surface needs to face the quasi-universal compensating mirror 5. For the aspheric surfaces not within the detection range of the quasi-universal compensating mirror 5, conventional adjustments can be made to the structural parameters of the quasi-universal compensating mirror according to the present invention, so aspheric surfaces in other parameter ranges can be detected. Using the quasi-universal compensating mirror 5 in the above-mentioned manner, the range of detectable aspheric surfaces is large, and it is possible to detect paraboloids with paraxial radius _r0 from 300 to 25000, hyperboloids with paraxial radius _r0 from 10 to 50000, and paraxial radius _r0 Ellipsoids from 400 to 50,000. The value of the eccentricity e varies greatly. For example, for a hyperboloid with a paraxial radius r ₀ of -700, the eccentricity e varies between -1 and -21.6. The compensation accuracy is high, and the compensation accuracy meets the Rayleigh criterion of ideal imaging, which is less than one-tenth of the wavelength. See Table 1, Table 2, Table 3, Table 4, and Table 5 for the detection results. The quasi-universal compensating mirror 5 can also detect various high-order aspheric surfaces. Each component of the quasi-universal compensating mirror ₅ of the present invention is a spherical mirror, which is small in size and light in weight. 4.5, so the design, manufacture, assembly, etc. can be realized, and it is relatively easy and convenient.

Table 1 The results of using the quasi-universal compensating mirror to detect the paraboloid

D(mm) r ₀ (mm) -S ₀ (mm) S ₀ '(mm) ΔW 47.34 -300.00   2680.280   187.892 0.060λ 53.94 -350.00   1987.123 192.774 0.016λ 59.53 -400.00   1449.432 272.088 0.011λ 66.25 -457.56   1200.000 206.272 0.010λ 70.95 -501.64   1050.000 211.579 0.021λ 78.15 -570.60 900.000   219.060 0.020λ 85.47 -642.31 800.000 226.021 0.019λ 90.66 -693.49 750.000   230.399 0.022λ 97.12 -758.44 700.000 235.601 0.023λ 105.46 -843.96 650.000 241.881 0.023λ 106.72 -961.72 600.000 249.617 0.023λ 156.12 -1393.55 500.000 272.082 0.028λ 163.60 -1500.00 474.869   280.032 0.023λ 190.584 -1800.00 450.531 289.080 0.014λ 205.81 -2000.00  429.913 298.061 0.017λ 245.758 -2500.00 401.493 313.044 0.016λ 283.046 -3000.00 379.889 327.125 0.029λ 323.111 -3500.00 369.667 334.840 0.013λ 361.198 -4000.00 360.060 342.841 0.033λ 396.382 -4500.00 350.050 352.076 0.016λ   428.368 -5000.00 339.758 362.695 0.008λ 457.160 -5500.00 329.493 374.639 0.044λ 522.986 -6500.00 319.440 387.903 0.038λ 584.389 -7500.00 310.390 401.450 0.049λ 621.228 -8000.00 309.480 402.909 0.009λ 687.884 -9000.00 305.335 409.796 0.043λ 745.998 -10000.00 299.317 420.570 0.026λ   1018.858 -15000.00 279.243 464.956 0.030λ   1284.242 -20000.00  269.198 493.792 0.016λ   1502.688 -25000.00 258.888 530.032 0.100λ

The eccentricity of each tested paraboloid in the table is: e=-1, and the detectable range of the paraxial radius is: -25000mm≤r ₀ ≤-300mm, which is only a rough range, and the paraboloid with the paraxial radius outside this range can also be detected. Its wave aberration: Δw ≤ λ/10.

Table 2 The results of detecting hyperboloids using quasi-universal compensating mirrors

r ₀ (mm) e D(mm) -S ₀ (mm) S ₀ '(mm) ΔW -10 -33.6 1.686 1800 194.803 0.044λ -20 -19.0 3.152 1520   198.889 0.027λ -40 -10.0 6.094 1430 200.587 0.012λ -60 -7.00 8.961 1320 203.023 0.011λ -80 -5.50 11.782 1240 205.109 0.013λ -200 -2.50 28.288 1030 212.426 0.005λ -250 -2.52 33.378 800 226.021 0.009λ -300 -2.28 39.324 750   230.399 0.008λ -350 -3.20 41.145 550 259.378 0.020λ -335.81 -2.2 43.108 700 235.601 0.039λ -446.79 -2.5 52.462 550 259.378 0.011λ -542.398 -2.5 60.908 500 272.082 0.041λ -562.27 -3.2 59.675 450   289.294 0.014λ -814.489 -3.2 80.063 400 313.932 0.013λ -500 -2.22 58.682 500 259.378 0.009λ -700 -2.57 74.226 450   289.294 0.009λ -900 -1.22   105.861 555   258.289 0.007λ -1100 -1.87   113.338 430   298.020 0.008λ -1300 -3.37 114.758 350 352.125 0.013λ -1500 -6.49   112.643 300  419.298 0.019λ -2000 -4.87   150.023 300  419.298 0.019λ -2500 -1.32 233.551 375 330.720 0.009λ -3000 -1.93 249.943 330 374.001 0.012λ -3500 -4.37 239.133 280 462.993 0.024λ -4000 -2.82 290.731 293 432.998 0.022λ -6000 -1.77 281.871 305 410.371 0.017λ -8000 -1.22 598.585 300  419.298 0.019λ -9000 -1.62 620.288 282 457.932 0.023λ -10000 -1.65 671.419 277 470.993 0.054λ -15000 -1.54 938.917 265 507.616 0.033λ -20000 -1.60   1169.737 255 545.935 0.035λ -25000 -1.20   1483.093 257 537.580 0.039λ -30000 -1.15   1728.475 253 554.683 0.044λ -40000 -1.32 2105.525 242 611.277 0.046λ -50000 -1.15   2584.033 240 623.431 0.046λ

The detectable range of paraxial radius is: -50000mm≤r ₀ ≤-10mm. Its wave aberration: Δw<λ/10. The eccentricity e varies widely.

Different paraxial radii r ₀ and eccentricities e can construct different hyperboloids. In order to describe in detail the range of hyperboloids that can be detected by the quasi-universal compensating mirror 5, we have analyzed different hyperboloids with the optical design software Zemax. And in Table 3, the variation range of hyperboloid eccentricity e that can be detected when the paraxial radius r ₀ is constant is given. According to the variation trend of the eccentricity e, it can be roughly judged which hyperboloids can be detected by the quasi-universal compensating mirror 5 .

Table 3 Variation range of the eccentricity e of the hyperboloid detectable by the quasi-universal compensating mirror

r ₀ (mm) Variation range of eccentricity e -10 Between -32.5 and -40 -20 Between -17 and -61.8 -40 Between -8.8 and -60 -60 Between -6.0 and -41 -80 Between -4.5 and -31 -200 Between -1.8 and -47 -250 Between -1.4 and -59 -300 Between -1.2 and -49.8 -350 Between -1 and -42.7 -500 Between -1 and -30.1 -700 Between -1 and -21.6 -900 Between -1 and -19.2 -1100 Between -1 and -15.7 -1300 Between -1 and -20.7 -1500 Between -1 and -25.3 -2000 Between -1 and -19 -2500 Between -1 and -15.3 -3000 Between -1 and -12.7 -3500 Between -1 and -10.9 -4000 Between -1 and -9.55 -5000 Between -1 and -7.65 -6000 Between -1 and -6.4 -8000 Between -1 and -4.8 -9000 Between -1 and -4.25 -10000 Between -1 and -3.84 -15000 Between -1 and -2.55 -20000 Between -1 and -1.92 -25000 Between -1 and -1.53 -30000 Between -1 and -1.28 -40000 Between -1 and -1.44 -50000 Between -1 and -1.15

The variation range of the eccentricity e given in the table is not exact, and can also be expanded in a small range on the edge.

Table 4 The results of quasi-universal compensation mirror detection ellipsoidal surface

r ₀ (mm) e D(mm) -S ₀ (mm) S ₀ '(mm) ΔW -400 -0.9 61.65 2000 192.65 0.004375λ -500 -0.85 73.35 1310 203.27 0.02715λ -700 -0.64 101.26 1200 206.27 0.0246λ -900 -0.8 116.00 716 233.83 0.02025λ -1000 -0.36   153.89 2000 192.65 0.0014λ -1200 -0.5 161.03 830 223.71 0.0423λ -1500 -0.3 216.78 1200 206.27 0.01595λ -1789.17 -0.36 223.646 800 226.02 0.0331λ -2000 -0.82 216.34 468 282.44 0.0352λ -2112.223 -0.36 270.11 700 235.60 0.0379λ -2500 -0.143 384.48 2000 192.65 0.0192λ -2862.468 -0.63 302.71 450   289.29 0.0065λ -3000 -0.38 348.17 540 261.65 0.0491λ -3148.225 -0.15 448.1452 1100  209.60 0.0383λ -4000 -0.7 385.61 391 319.54 0.02385λ -4143.15 -0.25 492.01 570 255.18 0.0166λ -5000 -0.48 498.41 410 308.19 0.00965λ -8000 -0.24 293.50 440 834.29 0.0077λ -10000 -0.75 789.33 314 395.84 0.0175λ -15000 -0.5   1183.76 314 395.84 0.01785λ -30000 -0.57 1996.69 275.5 475.07 0.0371λ -50000 -0.95   2690.12 244.5 596.98 0.04195λ

Table 5 Variation range of the eccentricity e of the ellipsoid surface detectable by the quasi-universal compensating mirror

r ₀ (mm) Eccentricity e r ₀ <400 e≤-0.9 r ₀ <-500 e≤-0.72 r ₀ <-700 e≤-0.51 r ₀ <-900 e≤-0.4 r ₀ <-1000 e≤-0.36 r ₀ <-1200 e≤-0.3 r ₀ <-1500 e≤-0.24 r ₀ <-2000 e≤-0.18 r ₀ <-2500 e≤-0.143 r ₀ <-3000 e≤-0.12 -50000< _r0 <-4000 e≤-0.09

The value of r ₀ given in Table 5 from -400 to -50000 is not an accurate range of detectable paraxial radius values, and radii outside these two values can also be detected.

Description of drawings

Fig. 1 is a schematic diagram of the universal compensating mirror and its positional relationship with the light source and the tested aspheric surface in the known technology. Fig. 2 is a schematic diagram of the quasi-universal compensating mirror of the present invention and its mutual positional relationship with the light source and the tested aspheric surface. Fig. 3 is a schematic diagram of the position and detection process of the quasi-universal compensating mirror of the present invention in the detection device. Fig. 4 is a curve diagram of the spherical aberration of the quasi-universal compensating mirror of the present invention and a curve diagram of the normal aberration of the tested paraboloid. Fig. 5 is a curve diagram of the quasi-universal compensating mirror of the present invention for compensating the rear wave aberration of the inspected parabola.

Detailed ways

As shown in Fig. 3, the quasi-universal compensating mirror 5 is designed in conjunction with a He-Ne laser light source, and the laser wavelength is 632.8nm. The tested aspheric surface 4 is a parabolic reflector, the diameter D is 100mm, and the relative diameter D/f' is 1/4. The optical structure parameters of the designed quasi-universal compensating mirror 5 are shown in Table 6. Such a design can make the quasi-universal compensating mirror 5 The universal compensating mirror 5 compensates the wave aberration ΔW of the tested aspheric surface 4 which is less than one-tenth of the laser wavelength.

Table 6 Optical structure parameters of quasi-universal compensating mirror

Composition of compensating mirror Lens Type Radius of curvature r _n (mm) Thickness Dn(mm) Interval dn(mm) Refractive index n Glass grade Clear aperture D _k (mm) Convex Planar Spherical Lens 6 convex flat r ₁ =325.2 D ₁ =4.0 d ₁ =4.0 1.48598 QK3 30 r ₂ =∞ Plano-concave spherical lens 7 flat concave r ₃ =∞ D ₂ =3.0 1.48598 QK3 r ₄ =325.2 d ₂ =4.0 Bi-convex spherical lens 8 biconvex r ₅ =174.3 D ₃ =4.5 1.74970 ZF6 _r6 = -558.6

The thickness d of the quasi-universal compensation mirror 5 is:

$\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; +</span>\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}$

According to the formula and Table 6, the thickness d of the designed quasi-universal compensating mirror 5 can be obtained as 19.5mm. When the distance between the quasi-universal compensating mirror 5 and the back focus F' of the standard spherical mirror 10 is S ₀ =-673.25mm, its compensation effect is shown in Fig. 4, and the compensation accuracy is shown in Fig. 5. It can be seen that the maximum wave after compensation is The aberration is only 0.021λ.

When detecting other aspheric surfaces, it is only necessary to move the quasi-universal compensating mirror 5 to a certain distance along the optical axis of the optical system relative to the back focus F' of the standard spherical mirror 10, so that the spherical aberration of the quasi-universal compensating mirror 5 is consistent with that of the tested aspheric surface 4 The normal aberrations are equal, and the compensation accuracy can meet the Rayleigh criterion, that is, the wave aberration ΔW is less than one-tenth of the wavelength. Table 1, Table 2, Table 3, Table 4, and Table 5 respectively show that the quasi-universal compensation Mirror 5 is the result of detecting some other types and aspheric surfaces of the same type with different optical parameters. The wave aberration ΔW in each table is calculated by using the Zemax optical design software according to the self-collimating optical path of the Tyman-Green interferometer. The distance between the light source and the quasi-universal compensating mirror 5 is -S ₀ , which is also the distance from the first surface of the quasi-universal compensating mirror 5 to the back focus F' of the standard spherical mirror 10 when testing the aspheric surface 4 to be tested. The distance determines the position of the quasi-universal compensating mirror 5 .

For high-order aspheric surfaces, according to the compensating principle of compensating mirrors, only the distance -S ₀ between the quasi-universal compensating mirror 5 and the standard spherical mirror 10 needs to be adjusted, and it can also be detected.

For the aspheric surface that is not within the compensation range of the quasi-universal compensating mirror 5, such as a paraboloid with a paraxial radius _r0 of 100 mm, some optical parameters of the quasi-universal compensating mirror 5 can be properly corrected, and another set of optical parameters can be designed. The quasi-universal compensating mirror 5 can adapt to the detection of aspheric surfaces in this range.

Determination of distance-S ₀ :

(1) The optical parameters of the measured aspheric surface 4 include paraxial radius r ₀ , aperture D and eccentricity e, and determine the initial distance of the quasi-universal compensating mirror 5 from the back focus F' of the standard spherical mirror 10 according to design experience;

(2) Utilize optical design software, such as Zemax software, with stepwise approximation method, calculate quasi-universal compensating mirror 5 to compensate the wave of tested aspheric surface 4 by quasi-universal compensating mirror 5 in the working light path of Teiman-Green interferometer 9 Aberration ΔW;

(3) When the wave aberration ΔW of the tested aspheric surface 4 compensated by the quasi-universal compensating mirror 5 is less than one-tenth of the wavelength of the light source, it is considered that the corresponding _-S0 is the back focus of the quasi-universal compensating mirror 5 from the standard spherical mirror 10 The exact distance of F';

(4) When actually testing the surface shape of the tested aspheric surface 4, the positions of the quasi-universal compensating mirror 5 and the tested aspheric surface 4 in the testing device are determined according to -S ₀ , S ₀ ′, r ₀ . S ₀ ′ is the image distance of the quasi-universal compensating mirror 5, which is calculated and determined by Zemax software according to -S ₀ and the optical parameters of the quasi-universal compensating mirror 5.

Claims (2)

1. A quasi-universal compensating mirror for optical aspheric detection, consisting of coaxial spherical lenses, characterized in that the convex-planar spherical lens (6), the plano-concave spherical lens (7), and the double-convex spherical lens (8) are coaxial sequentially Arrangement, the radius of curvature r ₁ of the first surface of the convex-flat spherical lens (6) is equal to the radius of curvature r ₄ of the second surface of the flat-concave spherical lens (7), the second surface of the convex-flat spherical lens (6) The radius of curvature r ₂ of the first surface of the plano-concave spherical lens ( ₇ ) is infinite, the front focal point of the convex-planar spherical lens (6) coincides with the rear focal point F of the standard spherical mirror (10), and the convex-planar spherical The light between the lens (6) and the plano-concave spherical lens (7) is parallel light, and the optical self-collimation method utilizes the light adjustment and positioning of plane reflection, so that the front focus O of the quasi-universal compensating mirror (5) is in line with the standard The back focus F of the spherical mirror coincides, and this point is also the position of the light source. The distance between it and the quasi-universal compensating mirror (5) is -S ₀ , thus determining the initial position of the quasi-universal compensating mirror (5), and the quasi-universal compensating mirror (5) ) in the double-convex spherical lens (8) compensates the advanced aberration of the convex-planar spherical lens (6) and the plano-concave spherical lens (7), and the spherical aberration of the quasi-universal compensating mirror (5) is the same as that of the tested aspheric surface (4). Normal aberrations are equal. 2. The quasi-universal compensating mirror according to claim 1, characterized in that, Convex Planar Spherical Lens (6): r ₁ =325.2, r ₂ =∞, thickness D ₁ =4.0, the grade of optical glass used is QK3; Plano-concave spherical lens (7): r ₃ =∞, r ₄ =325.2, thickness D ₂ =3.0, the grade of optical glass used is QK3; Bi-convex spherical lens (8): The radius of curvature of the first surface r ₅ =174.3, the radius of curvature of the second surface r ₆ =-558.6, the thickness D ₃ =4.5, and the grade of optical glass used is ZF6; The distance between the convex-planar spherical lens (6) and the plano-concave spherical lens (7): d ₁ =4.0; The distance between the plano-concave spherical lens (7) and the double-convex spherical lens (8): d ₂ =4.0; Unit: mm.

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