SU1652955A1 - Planochromatic objective of microscope - Google Patents

Abstract

FIELD: optical instrumentation; used in biological microscopes. Purpose invented Shadows - enhanced performance by providing high image quality when working with a cover glass of increased thickness. The lens contains an aplanatic meniscus 1, duplex positive components from lenses 2-3.5-6, a single two-convex lens 4 and a duplex negative component from lenses 7-8. 1 il.

Description

The invention relates to optical instrumentation, in particular to microscope lenses, and more specifically to planachromatic lenses, and can be used in biological inverted microscopes, flow microcytophotometers when studying objects of biotechnology, medicine and biology.

The purpose of the invention is the expansion of operational capabilities by providing high quality images when working with a cover glass of increased thickness.

The drawing shows a schematic optical diagram of a microscope objective.

The lens is made of five components: the first is the aplanatic meniscus T, the second is positive two-glued from biconcave 2 and biconvex 3 lenses, the third is biconvex lens 4, the fourth is positive double-glued from negative 5 and positive 6 menisci, and the fifth is negative two-glued from biconvex 7 and 8 lenses.

'The execution of the front component in the form of an aplanatic meniscus 1 from a material with the main optical constants nt> 1.7 and Vi> 50, subsequent double glued positive components, between which a single positive lens 4 is placed, and a negative double glued component from lenses 7 and 8 with the ratios of the main parameters of the materials ns - ηγ> 0.2: νι> 90; 143> 40 with a difference of partial relative dispersions of not more than 0.004 ensured high image quality with a cover glass thickness of 1 to 1.7 mm while maintaining a high numerical aperture of up to 0.65.

As an example of a specific implementation, two types of planachromatic lenses for a microscope are offered.

’Type I lens.

The lens has the following main characteristics:

Increase, krat40

Numerical Aperture 0.65

Focal Length, mm 6.2

Linear field in the image plane, mm20 Working distance, mm2.2

The thickness of the cover glass, mm 1.3-1.7

Type II lens.

The lens has the following main characteristics

Magnification, time 25

Numeric Aperture 0.50

Focal Length 10.0 mm

Linear field in the image plane, mm · 20.0

Working distance 6.0 mm

The thickness of the cover glass, mm From 1.0 to 2.0

From the analysis of aberrations calculated for these two types of lens, it is seen that a high degree of correction is achieved within the entire field. For the spectral region Λ = 546.1 nm, Ac. = 653.0 nm, λι = 486.1 nm and the thickness of the cover glass 1-

1.7 mm wave aberrations for a point on the axis do not exceed 0.1 λ for a fundamental wavelength of 0.4 2 and 0.5 λ for a line C and F.

The proposed lens has an increased working distance, it provides high aberration correction for the thickness of the cover glass 1; 1.5 and 1.7 mm, which makes it possible to use the lens in biological inverted microscopes to study biotechnology objects placed in special dishes with wall thicknesses up to 1.7 mm, and, in addition, work under the microscope using micromanipulators is provided.

The use of the lens for biotechnology, medicine and biology will provide new information on the growth of tissue cultures, changes in their physico-chemical and antigenic composition.

Claims (1)

Claim A planachromatic microscope objective containing five components, the first of which is the aplanatic meniscus with the concavity facing the object, the second positive two-glued component from the negative and biconvex lenses, the third is the biconvex lens, the fourth is the positive two-glued meniscus facing concavity to the image, and the fifth is the negative meniscus glued from a biconvex and biconcave lenses, characterized in that. in order to expand operational capabilities by ensuring high image quality when working with a cover glass of increased thickness, so the second component is a negative lens biconcave, the third component is made as a single lens, the fourth component is glued from negative and positive menisci, while the second and fifth components each of the materials is made with a difference in refractive indices of more than 0.2 and a difference in dispersion coefficients of more than 50, and with a growth equal to the distance between one third m and the distance between the first and second components of the fourth components.