20X42 telescope system

Abstract

The invention belongs to the technical field of telescope manufacturing, and discloses a 20 * 42 telescope system which is characterized in that an objective first lens, an objective second lens, a focusing lens, a semi-pentaprism, a roof prism, a rhombic prism, an eyepiece first lens, an eyepiece second lens, an eyepiece third lens and an eyepiece fourth lens are sequentially arranged in the optical axis direction from the object side to the image side. The visual field of the whole machine is 3.25 degrees, the exit pupil diameter is 2.1 mm, the exit pupil distance is 35 mm, the nearest focusing distance is 8 m, and the image stabilization range is + / -5 degrees.

Description

Technical Field

[0001] The present invention relates to the technical field of telescope manufacturing, in particular to a 20X42 telescope system. Background Art

[0002] In the telescope optical system, the field of view of a high-magnification telescope is usually narrower. The higher the magnification, the narrower the field of view and the greater the image jitter. This is because the magnification of the telescope is calculated by the ratio of the focal length of the objective lens to the focal length of the eyepiece. When the magnification increases, in order to maintain the clarity of the image, the design of the telescope often requires a longer focal length or a larger lens combination, which will result in a reduction in the field of view. When the magnification of the telescope is 20 times, the field of view of many telescopes will be less than 3 degrees, and the exit pupil distance will be shortened accordingly. Summary of the invention

[0003] The object of the present invention is to provide a 20X42 telescope system to solve the problems raised in the above background technology.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a 20X42 telescope system, characterized in that: an objective lens first lens, an objective lens second lens, a focusing lens, a half pentaprism, a roof prism, a rhombus prism, an eyepiece first lens, an eyepiece second lens, an eyepiece third lens, an eyepiece fourth lens, and an eyepiece fifth lens are sequentially arranged along the optical axis from the object side to the image side; The first lens of the objective lens and the second lens of the objective lens form a cemented lens, the first lens of the objective lens is a biconvex lens, the second lens of the objective lens is a concave-convex lens, the concave surface of which faces the object side, and the focusing lens is a concave-convex lens, the concave surface of which faces the object side; The first lens of the eyepiece is a biconcave lens, the second lens of the eyepiece is a concave-convex lens with the concave surface facing the object side, the third lens of the eyepiece and the fourth lens of the eyepiece form a cemented lens, the third lens of the eyepiece is a concave-convex lens with the convex surface facing the object side, the fourth lens of the eyepiece is a biconvex lens, and the fifth lens of the eyepiece is a plano-convex lens with the convex surface facing the object side.

[0005] As a preferred technical solution, the object side curvature radius of the first lens of the objective lens is 65.1mm, the image side curvature radius is 103.38mm, the center thickness is 8mm, the material is glass H-BAK2, and the outline diameter is 44mm; the object side curvature radius of the second lens of the objective lens is -103.38mm, the image side curvature radius is 2758.2mm, the center thickness is 2.5mm, the material is glass H-ZF2, and the outline diameter is 44mm; the object side curvature radius of the focusing lens is -76.1mm, the image side curvature radius is 517.76mm, the center thickness is 2mm, the material is glass H-K9L, and the outline diameter is 23.5mm; The first lens of the eyepiece has a curvature radius of -24.32mm on the object side, a curvature radius of -24.32mm on the image side, a center thickness of 2.1mm, and is made of glass H-K9L with a diameter of 15mm; the second lens of the eyepiece has a curvature radius of -42.74mm on the object side, a curvature radius of 16.95mm on the image side, a center thickness of 5.9mm, and is made of glass H-LAK6A with a diameter of 25mm; the third lens of the eyepiece has a curvature radius of 124.9mm on the object side, a curvature radius of -18.97mm on the image side, and a center thickness of 5.9mm. The thickness is 2.1mm, the material is glass H-ZF72A, and the diameter is 25mm; the object side curvature radius of the fourth lens of the eyepiece is 18.97mm, the image side curvature radius is 35.18mm, the center thickness is 9.5mm, the material is glass H-LAK6A, and the diameter is 25mm; the object side curvature radius of the fifth lens of the eyepiece is 19.34mm, the image side is flat, the center thickness is 6.1mm, the material is glass H-LAK1A, and the diameter is 25mm. Positive numbers in the curvature radius represent convex surfaces, and negative numbers represent concave surfaces.

[0006] As an optimal technical solution, the total length of the entire telescope system is 188.2 mm, the distance between the second lens of the objective lens and the focusing lens along the optical axis is 58 mm, the distance between the focusing lens and the semi-penta prism is 25 mm, the distance between the roof prism and the rhombus prism is 15 mm, the distance between the rhombus prism and the first lens of the eyepiece is 3.2 mm, the distance between the first lens of the eyepiece and the second lens of the eyepiece is 6.74 mm, the distance between the second lens of the eyepiece and the third lens of the eyepiece is 0.7 mm, and the distance between the fourth lens of the eyepiece and the fifth lens of the eyepiece is 0.4 mm.

[0007] Compared with the prior art, the beneficial effects achieved by the present invention are: The optical system of the telescope of the present application has a magnification of 20 times, a field of view of 3.25°, an exit pupil diameter of 2.1 mm, an exit pupil distance of 35 mm, a minimum focusing distance of 8 m, and an image stabilization range of plus or minus 5 degrees. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 is a schematic diagram of an optical system of the present invention; Figure 2 is a field curvature distortion diagram of the present invention; Figure 3 is a spot diagram of the present invention; Figure 4 It is the grid distortion map of the present invention. DETAILED DESCRIPTION

[0009] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0010] As attached Figure 1-4 As shown, the present invention provides the following technical solution: a 20X42 telescope system, characterized in that: an objective lens first lens 1, an objective lens second lens 2, a focusing lens 3, a half pentaprism 4, a roof prism 5, a rhombus prism 6, an eyepiece first lens 7, an eyepiece second lens 8, an eyepiece third lens 9, an eyepiece fourth lens 10, and an eyepiece fifth lens 11 are sequentially arranged along the optical axis from the object side to the image side; The first objective lens 1 and the second objective lens 2 form a cemented lens, the first objective lens 1 is a biconvex lens, the second objective lens 2 is a concave-convex lens, the concave surface of which faces the object side, and the focusing lens 3 is a concave-convex lens, the concave surface of which faces the object side; The first lens 7 of the eyepiece is a double concave lens, the second lens 8 of the eyepiece is a concave-convex lens with the concave surface facing the object side, the third lens 9 of the eyepiece and the fourth lens 10 of the eyepiece form a cemented lens, the third lens 9 of the eyepiece is a concave-convex lens with the convex surface facing the object side, the fourth lens 10 of the eyepiece is a double convex lens, and the fifth lens 11 of the eyepiece is a plano-convex lens with the convex surface facing the object side. Only the above 8 lenses of the telescope system have optical power.

[0011] As a preferred technical solution, the object side curvature radius of the first lens 1 of the objective lens is 65.1mm, the image side curvature radius is 103.38mm, the center thickness is 8mm, the material is glass H-BAK2, and the outline diameter is 44mm; the object side curvature radius of the second lens 2 of the objective lens is -103.38mm, the image side curvature radius is 2758.2mm, the center thickness is 2.5mm, the material is glass H-ZF2, and the outline diameter is 44mm; the object side curvature radius of the focusing lens 3 is -76.1mm, the image side curvature radius is 517.76mm, the center thickness is 2mm, the material is glass H-K9L, and the outline diameter is 23.5mm; The first lens 7 of the eyepiece has a curvature radius of -24.32mm on the object side, a curvature radius of -24.32mm on the image side, a center thickness of 2.1mm, and is made of glass H-K9L with a diameter of 15mm; the second lens 8 of the eyepiece has a curvature radius of -42.74mm on the object side, a curvature radius of 16.95mm on the image side, a center thickness of 5.9mm, and is made of glass H-LAK6A with a diameter of 25mm; the third lens 9 of the eyepiece has a curvature radius of 124.9mm on the object side, a curvature radius of -18.97mm on the image side, and a center thickness of 5.9mm. The degree is 2.1mm, the material is glass H-ZF72A, and the diameter is 25mm; the object side curvature radius of the fourth lens 10 of the eyepiece is 18.97mm, the image side curvature radius is 35.18mm, the center thickness is 9.5mm, the material is glass H-LAK6A, and the diameter is 25mm; the object side curvature radius of the fifth lens 11 of the eyepiece is 19.34mm, the image side is flat, the center thickness is 6.1mm, the material is glass H-LAK1A, and the diameter is 25mm. The positive number in the curvature radius indicates a convex surface, and the negative number indicates a concave surface.

[0012] As a preferred technical solution, the total length of the entire telescope system is 188.2 mm, the distance between the second lens 2 of the objective lens and the focusing lens 3 along the optical axis direction is 58 mm, the distance between the focusing lens 3 and the semi-penta prism 4 is 25 mm, the distance between the roof prism 5 and the rhombus prism 6 is 15 mm, the distance between the rhombus prism 6 and the first lens 7 of the eyepiece is 3.2 mm, the distance between the first lens 7 of the eyepiece and the second lens 8 of the eyepiece is 6.74 mm, the distance between the second lens 8 of the eyepiece and the third lens 9 of the eyepiece is 0.7 mm, and the distance between the fourth lens 10 of the eyepiece and the fifth lens 11 of the eyepiece is 0.4 mm.

[0013] The telescope optical system of the present application has a magnification of 20 times, a field of view of 3.25°, an exit pupil diameter of 2.1 mm, an exit pupil distance of 35 mm, a minimum focusing distance of 8 m, an image stabilization range of plus or minus 5 degrees, and an objective lens first lens 1, an objective lens second lens 2 and a focusing lens 3 form an objective lens group. The focal length of the objective lens group is 234.7 mm. The focusing lens 2 can move forward and backward to focus. The focusing lens 3 moves back 3.7 mm, corresponding to a minimum focusing distance of 8 m, and the focusing lens 3 moves forward 1 mm, corresponding to 14 degrees of diopter in the infinity direction.

[0014] The half pentaprism 4 and the roof prism 5 form a Bihan prism group, which is mounted on a special prism seat. The rhombus prism 6 is used to adjust the pupil distance of different people.

[0015] The eyepiece first lens 7, the eyepiece second lens 8, the eyepiece third lens 9, the eyepiece fourth lens 10 and the eyepiece fifth lens 11 constitute an eyepiece group, and the focal length of the eyepiece group is 11.7 mm.

[0016] Attached Figure 2The field curvature distortion diagram of this application is an important tool for evaluating the imaging quality of optical systems. It reveals the influence of field curvature and distortion on imaging effects. It is also called field curvature. It describes that after a plane object passes through a lens system, the clear image points formed are not on a plane, but on a curved surface. Distortion reflects the similarity between the object and the image, including barrel distortion and pincushion distortion. We use the attached Figure 2 It can be seen that Figure 2 In the field curvature curve, the wavelengths are 0.486um, 0.588um, and 0.656um, S represents the arc vector, and T represents the meridian quantity. From the field curvature curve, we can see that the field curvature of this application is very small, the edges and the center are relatively clear, the image quality is good, and the maximum field of view is 1.625°, so the field of view of the binoculars is 3.25°.

[0017] Figure 2 The distortion curve and Figure 4 The grid distortion curve shows that the maximum distortion of this application is 3.57, which is less than 5%. After the telescope forms an image, the human eye cannot observe the deformation of the image.

[0018] Attached Figure 3 It is the point diagram of the present application. The distribution of points in the point diagram should be uniform and dense, without obvious abnormal values ​​or outliers. The more evenly distributed the data is, the more stable the imaging quality is. The energy of the optical system point diagram in the present application is relatively concentrated, and the imaging is relatively clear.

[0019] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A 20X42 telescope system, characterized in that: An objective lens first lens (1), an objective lens second lens (2), a focusing lens (3), a half pentaprism (4), a roof prism (5), an oblique square prism (6), an eyepiece first lens (7), an eyepiece second lens (8), an eyepiece third lens (9), an eyepiece fourth lens (10), and an eyepiece fifth lens (11) are sequentially arranged along the optical axis from the object side to the image side; The first objective lens (1) and the second objective lens (2) form a cemented lens, the first objective lens (1) is a biconvex lens, the second objective lens (2) is a concave-convex lens, the concave surface of the lens faces the object side, and the focusing lens (3) is a concave-convex lens, the concave surface of the lens faces the object side; The first eyepiece lens (7) is a biconcave lens, the second eyepiece lens (8) is a concave-convex lens, with the concave surface facing the object side, the third eyepiece lens (9) and the fourth eyepiece lens (10) form a cemented lens, the third eyepiece lens (9) is a concave-convex lens, with the convex surface facing the object side, the fourth eyepiece lens (10) is a biconvex lens, and the fifth eyepiece lens (11) is a plano-convex lens, with the convex surface facing the object side. The telescope system has only the above eight lenses having optical power.

2. A 20×42 telescope system according to claim 1, characterized in that: The first lens (1) of the objective lens has an object side curvature radius of 65.1 mm, an image side curvature radius of 103.38 mm, a center thickness of 8 mm, is made of glass H-BAK2, and has a profile diameter of 44 mm; the second lens (2) of the objective lens has an object side curvature radius of -103.38 mm, an image side curvature radius of 2758.2 mm, a center thickness of 2.5 mm, is made of glass H-ZF2, and has a profile diameter of 44 mm; the focusing lens (3) has an object side curvature radius of -76.1 mm, an image side curvature radius of 517.76 mm, a center thickness of 2 mm, is made of glass H-K9L, and has a profile diameter of 23.5 mm; The first lens (7) of the eyepiece has a curvature radius of -24.32 mm on the object side, a curvature radius of -24.32 mm on the image side, a center thickness of 2.1 mm, and is made of glass H-K9L with a diameter of 15 mm; the second lens (8) of the eyepiece has a curvature radius of -42.74 mm on the object side, a curvature radius of 16.95 mm on the image side, and a center thickness of 5.9 mm, and is made of glass H-LAK6A with a diameter of 25 mm; the third lens (9) of the eyepiece has a curvature radius of 124.9 mm on the object side, a curvature radius of -18.97 mm on the image side, and a center thickness of The radius of curvature of the object side of the eyepiece fourth lens (10) is 18.97 mm, the radius of curvature of the image side is 35.18 mm, the center thickness is 9.5 mm, and the material is glass H-LAK6A with a diameter of 25 mm; the radius of curvature of the object side of the eyepiece fifth lens (11) is 19.34 mm, the image side is flat, the center thickness is 6.1 mm, and the material is glass H-LAK1A with a diameter of 25 mm, where a positive radius of curvature indicates a convex surface, and a negative radius of curvature indicates a concave surface.

3. A 20×42 telescope system according to claim 1, characterized in that: The total length of the entire telescope system is 188.2 mm, the distance between the second lens (2) of the objective lens and the focusing lens (3) along the optical axis is 58 mm, the distance between the focusing lens (3) and the semi-penta prism (4) is 25 mm, the distance between the roof prism (5) and the rhombus prism (6) is 15 mm, the distance between the rhombus prism (6) and the first lens (7) of the eyepiece is 3.2 mm, the distance between the first lens (7) of the eyepiece and the second lens (8) of the eyepiece is 6.74 mm, the distance between the second lens (8) of the eyepiece and the third lens (9) of the eyepiece is 0.7 mm, and the distance between the fourth lens (10) of the eyepiece and the fifth lens (11) of the eyepiece is 0.4 mm.

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