RU2571005C1 - Plan-apochromatic high-aperture microlens with long operating distance - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: microlens comprises five series-arranged components. The first component is a meniscus, the second and third components are glued from two lenses, the fourth component comprises a positive lens and the fifth component includes a biconcave lens. The meniscus of the first component faces the image space with its concave side and is glued with a biconvex lens. The second component is glued from a negative meniscus, which faces the image space with its concave side, and a biconvex lens. The third component is glued from a biconvex lens and a negative meniscus which faces the object space with its concave side. In the fourth component, the positive lens is glued from a positive meniscus, which faces the image space with its concave side, and a biconvex lens. In the fifth component, the biconcave lens is glued with a positive meniscus which faces the image space with its concave side.

EFFECT: longer operating distance while maintaining plan-apochromatic correction and correct chromatism of magnification.

2 cl, 1 dwg, 1 tbl, 1 app

Description

The present invention relates to optical instrumentation, namely, microscope lenses, and can be used for visual observation and photographing of low-contrast microscopic structures that are at the limit of the resolution of light microscopes in natural light, visible luminescence light, in polarized light by the bright field, dark field method phase contrast, for use in reflected light systems in metallography, in microelectronics for working with monographic structures ramie, mikroinektorov equipment for different tasks in the cell, developmental and genetic engineering, etc.

A planochromatic high-aperture microscope objective [1] is known that contains five components, the first of which is a positive meniscus facing concavity into the object space, the second is a single positive component, the third is glued from a positive biconvex and negative lenses, the fourth is a single positive component and the fifth is negative a component facing concavity into the image space and glued from positive and negative lenses.

The lens has a high input aperture, well-corrected mono- and chromatic aberrations of the axial and off-axis beams, but the free working distance does not exceed 2 mm.

The closest technical solution to the claimed invention is a planochromatic high aperture micro lens with a large working distance [2].

The lens contains five components, the first of which is made in the form of a meniscus facing concavity to the space of objects, the second positive component is glued from a biconvex lens and a negative meniscus facing concavity to the space of objects, the third two-glued component is made of a negative meniscus facing concavity to the image space , and a biconvex lens, the fourth component contains a single positive lens, and the fifth component is made of a single biconcave th lens and two menisci facing concavity to the space of objects.

The lens has a high input aperture (10 × 0.38), a sufficiently high point correction on the axis and in the field, a large linear image field (25 mm), and an increased working distance (4.5 mm).

But the free working distance is not enough for use in reflected light systems in metallography, in microelectronics for working with monographic structures, for assembling microinjectors for various tasks, in cellular, ontogenetic and genetic engineering, etc.

Modern microscope models require a high-aperture plano-chromatic micro-lenses, which have improved correction of monochromatic and chromatic aberrations on the axis and throughout the image field with multiple increased working distances.

The main task, the solution of which the invention is directed, is a multiple increase in the working distance while maintaining the planochromatic correction and corrected chromaticity of the increase.

The problem is solved using the proposed planochromatic high-aperture micro lens with a large working distance, which, like the prototype, contains five components in series, the first of which is made in the form of a meniscus, the second and third are glued from two lenses, the fourth contains a positive lens and the fifth component Includes a negative biconcave lens.

In contrast to the prototype, in the present invention, the meniscus of the first component is concave to the image space and glued with a positive biconvex lens, the second component is glued from a negative meniscus facing the concavity to the image space, and the biconvex positive lens, the third component is glued from a positive biconvex lens and the negative meniscus facing concavity to the space of objects, in the fourth component the positive lens ying glued from positive meniscus concavity facing the space of the image, and a biconvex positive lens, and a fifth biconcave negative lens component made of a glued with a positive meniscus facing concavity to space image.

In addition, the dispersion coefficient of the positive lenses of the first, second and third components, as well as the positive meniscus of the fourth component is 90≤ν _d ≤95, and the refractive index of the negative menisci in the bonded lenses of the second and third components and the positive biconvex lens in the bonded lens of the fourth component 1.6≤n _d ≤1.65, and their dispersion coefficient has a value of 42≤ν _d ≤45.

The essence of the invention lies in the fact that the first component is double-glued from a meniscus and a positive biconvex lens, the second component is double-glued from a negative meniscus and a positive biconvex lens, the third component is double-glued from a biconvex positive lens and negative meniscus, and the fourth is glued from a positive meniscus and double , and the fifth - glued from a negative biconcave lens and a positive meniscus, allowed several times increase be working front section (approximately 5.12 times), and the selection of the dispersion coefficient of the refractive index and allowed to keep planapohromaticheskuyu correction with the corrected chromatic aberration increase above.

At the same time, it is possible to work in systems of reflected light in metallography, in microelectronics for working with monographic structures, microinjectors for various tasks, in cellular, ontogenetic and genetic engineering, etc., requiring very large working distances, high input aperture and observation simultaneously the entire linear field of view with high contrast.

Based on the foregoing, we can conclude that a new set of essential features of the claimed invention allowed us to obtain a technical result consisting in a several-fold increase in free working distance, while maintaining a sufficiently high input aperture (0.3) and planochromatic correction, due to which the entire field is simultaneously observed view with high image quality.

The proposed planochromatic high-aperture micro lens with a large working distance is illustrated by the drawing, in which in FIG. 1 presents its optical scheme, as well as the Appendix, which gives the design parameters and aberration releases.

The inventive planachromatic high-aperture micro lens with a large working distance contains five components, the first of which is made in the form of a glued lens containing a meniscus 1, facing concavity to the image space, and a biconvex positive lens 2, the second component is double-glued from the negative meniscus 3, facing concavity to the space image, and a positive biconvex lens 4, the third two-glued component is made of a positive biconvex lens 5 and a negative meniscus 6 facing concavity to the space of objects, the fourth two-glued component is made of a positive meniscus 7 facing concavity to the image space and a biconvex lens 8, and a fifth component containing a negative biconcave lens 9 glued with a positive meniscus 10 facing concavity to the image space .

The proposed lens works as follows.

The lens works with a tube lens f ′ = 200 mm.

Rays from the object of observation located in the front focal plane of the micro-lens pass through the first glued component I - meniscus 1 and positive biconvex lens 2, the second component II - glued negative meniscus 3 and positive biconvex lens 4, forming an imaginary image, introducing negative spherical aberration, coma, negative astigmatism and curvature, further components III - glued biconvex lens 5 and meniscus 6, and component IV - glued positive meniscus 7 and biconvex positive lens 8, form a real image aligned with the front focal plane of component V, increasing negative spherical aberration, compensating for coma, astigmatism and image curvature, and component V - glued biconcave lens 9 and meniscus 10, transfer the image to infinity, forming a planochromatic image with corrected chromatism increase (HRU = 0%).

According to the proposed scheme, a micro lens with a magnification of 10 ^x , a numerical aperture of 0.3, a linear image field of 25 mm and a working distance of 33.7 mm is implemented.

Table 1 presents the Strehl number, which characterizes the image quality of the lens for the relative values of the image values.

Table 1 Rel image value Strehl number one 0.72 0.866 0.82 0.707 0.88 0.5 0.92 0 0.93

INFORMATION SOURCES

1. Russian Federation, patent 2195008, IPC: G02B 21/02, 2000

2. Russian Federation, patent 2497163, IPC: G02B 21/02, 2013 - prototype.

Claims (2)

1. Plano-chromatic high-aperture micro lens with a large working distance, containing five components in series, the first of which is made in the form of a meniscus, the second and third are glued from two lenses, the fourth contains a positive lens and the fifth component includes a negative biconcave lens, characterized in that the meniscus of the first component is turned concavity to the image space and made glued with a positive biconvex lens, the second component is glued from the negative meniscus facing concavity to the image space and the biconvex positive lens, the third component is glued from the positive biconvex lens and the negative meniscus facing the concavity to the space of objects, in the fourth component the positive lens is glued from the positive meniscus facing concavity to the image space , and a positive biconvex lens, and in the fifth component, the negative biconcave lens is glued to itelnym meniscus facing the concavity to the space of the image. 2. Plano-chromatic high-aperture micro lens with a large working distance according to claim 1, characterized in that the dispersion coefficient of the positive lenses of the first, second and third components, as well as the positive meniscus of the fourth component, has a value of 90

$${\nu }_d$$

95, and the value of the refractive index of the negative menisci in the bonded lenses of the second and third components and the positive biconvex lens in the bonded lens of the fourth component 1.6

n _d

1.65, and their dispersion coefficient has a value of 42

$${\nu }_d$$

45.

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