SU1254403A1 - Telecentric lens - Google Patents

Abstract

The invention relates to optical instrumentation and can be used to transmit images to the input end of a light guide when observing fixed or moving objects. The purpose of the invention is to increase the linear field in the image space and the luminosity with a simultaneous decrease in the position chromatism and spherochromatic aberration. The negative component 1 is a soit of positive lenses 6 and 7 with a double-bent lens 8 between them. The first surface of the component is flattened, and the last is in the form of a fourth-order planoid combined with the aperture diaphragm 4, which made it possible to substantially correct the spherical aberration in the system. In component 3, the thickness of the double convex lens 9 is 0.7 of the focal length of the lens. The field diaphragm 5 is aligned with the positive meniscus 10. Between the components 1 and 3 there is a flat convex lens 2, made in the same way as the lenses 6,7,9, made of glass with a refractive index of about 1.6. The lens has high image quality within the floor - with a contrast of 0.1 min. resolution not less than 12 lin / mm. 1 il. about $ (L S

Description

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From 6 to 5, the test relates to optical instrumentation, in particular to optical systems of common endoscopy, and can be used to transmit images to the input end of a light guide when observing direct or moving objects.

The aim of the invention is to increase the linear field in the image space and the aperture ratio while simultaneously reducing the chromatism of the position and the spherochromatic aberration. The drawing shows the optical layout of the lens.

The lens consists of negative 1, positive 2 and 3 components, aperture 4 and field 5 diaphragms.

Component 1 is made up of two positions of lens lenses 6 and 7 glued together with a symmetric double-concave lens 8 between them, the first surface of the component is flat, and the last is in the form of a fourth order plane, the radius of curvature of which is flat at the top and the shape is determined expression z + i)) S where f and y are the coordinates of surface points. Component 2 is positive and is convex in the form of a convex lens. The positive component 3 consists of a two-convex lens 9 and a positive meniscus 10, the Aperture diaphragm 4 is combined with the last surface

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water), and therefore the aperture of the lens.

At the same time, the presence of an aspherical surface in combination with the action of components 2 and 3 with the established values of their design parameters makes it possible to correct the astigmatic components and aberrations of broad oblique beams of rays in an objective, which makes it possible to increase the linear field in the image space. up to about 47 mm. ,

The lens has the following characteristics: focal length f 80.54 mm; numerical aperture in the image space A 0.21; angular field in the space of objects; linear field in the space of images 46.5 mm. An image is formed on the last surface of the lens, which is the gluing surface with the light guide.

25 The lens has a high image quality within the floor - with a contrast of 0.1, the minimum resolution is at least 12 lines / mm.

Claims (1)

30. Formula of inventions. The telecentric lens, including two glued components, the second of which is positive, has component 1, and the field diaphragm 5 -, "" from a two-convex lens and menisJ tf L eTTf G Ch1TG "H-S: T ph T" f. tvw l D. "hl". ".. with the last surface of the component 3, which is the surface of the image, that it is necessary to perform gluing of the component 3 with the light guide. The positive lenses 2,6,7,9,10 are made of glass with a refractive index of 1.6130. I. The shape and interposition of the components, lenses and diaphragms, as well as the materials used, made it possible to calculate the telecentric lens based on the need to increase the linear field and luminosity while reducing the chromatism of the position and spherochromatic aberration. Thus, giving the last surface of the first component the shape of a fourth-order planoid made it possible to largely correct the spherical aberration in the system, which contributed to an increase in the relative aperture to 1: 1.5 (for a system not glued to light ka, aperture and field diaphragms, characterized in that, in order to increase the linear field in the image space and luminosity while reducing the chromatism of the position and the spherochromatic aberration, a flat-glass lens is inserted between the components, the first component is filled with a negative one consisting of two positive lenses with  located between them symmetric. double-concave lens, the first surface of the component is flat and the last is aspherical, made in the form of the fourth planeoid 50 times, with which the aperture of the aperture is combined, and in the second component, the meniscus is made positive, and the thickness of the two-convex lens is 0.7 focal length 55 lenses, and all positive lenses, except the last, are made of a material with a refractive index nj, on the order of 1.6. 25 The lens has a high image quality within the floor - with a contrast of 0.1, the minimum resolution is at least 12 lines / mm. 30. Formula of inventions. A telecentric lens, including two glued components, the second of which is positive, consists of a two-fold lens and a meniscus L eTTf G Ch1TG H-S: T f T f f. tvw l D. "hl". ".. ka, aperture and field diaphragms, characterized in that, in order to increase the linear field in the image space and luminosity while reducing the chromatism of the position and the spherochromatic aberration, a flat-glass lens is inserted between the components, the first component is filled with a negative one consisting of two positive lenses with located between them symmetric. double-concave lens, the first surface of the component is flat and the last is aspherical, made in the form of the fourth planeoid the order with which the aperture of the aperture is aligned, and in the second component the meniscus is made positive, with the thickness of the two-convex lens being 0.7 focal length the lens, and all positive lenses, except the last, are made of a material with a refractive index of nj, on the order of 1.6.