Binocular telescope

Abstract

The utility model discloses a binocular telescope. Comprising a first positive-focal-power biconvex objective lens, a second negative-focal-power meniscus objective lens, a third positive-focal-power meniscus objective lens, a fourth negative-focal-power meniscus objective lens, a semi-pentaprism, a roof prism and a first negative-focal-power biconcave objective lens which are sequentially arranged from the object side to the observation side in the optical axis direction. The first lens is a positive-power biconvex eyepiece lens, the second lens is a positive-power biconvex eyepiece lens, the third lens is a positive-power biconvex eyepiece lens, the fourth lens is a negative-power meniscus eyepiece lens, and the fifth lens is a positive-power meniscus eyepiece lens; during focusing, the objective fourth lens moves back and forth along the optical axis direction. The exit pupil diameter of the binocular telescope ranges from 3.5 mm to 4.5 mm, the exit pupil distance ranges from 15 mm to 18 mm, the field angle ranges from 6 degrees to 6.5 degrees, and the binocular telescope has the advantages of being high in resolution, small in chromatic aberration, small in size and light in weight.

Description

Technical Field

[0001] The utility model relates to the technical field of optical lenses, in particular to a pair of binoculars. Background Art

[0002] Binoculars are used to magnify distant objects through an optical system and allow them to enter the human eye, making it easier to observe details. They can be used for observing outdoor activities, watching games, watching concerts, etc. The optical systems of existing binoculars have different effects due to different design concepts. Existing binoculars have the defects of low resolution and poor user experience. Utility Model Content

[0003] Therefore, the technical problem to be solved by the utility model is to overcome the defects of low resolution and poor user experience of binoculars in the prior art, thereby providing a binoculars.

[0004] In order to solve the above technical problems, the technical solution of the utility model is as follows:

[0005] A binoculars, comprising an objective lens group, a Pehan prism group, and an eyepiece group, which are sequentially arranged from the object side to the observation side along the optical axis direction;

[0006] The objective lens group comprises a first objective lens of a positive power biconvex type, a second objective lens of a negative power meniscus type, a third objective lens of a positive power meniscus type, and a fourth objective lens of a negative power meniscus type, which are sequentially arranged along the optical axis from the object side to the observation side;

[0007] The Behan prism group includes a half pentaprism and a roof prism arranged in sequence from the object side to the observation side along the optical axis;

[0008] The eyepiece group includes a first eyepiece lens of a negative optical focal length biconcave type, a second eyepiece lens of a positive optical focal length biconvex type, a third eyepiece lens of a positive optical focal length biconvex type, a fourth eyepiece lens of a negative optical focal length meniscus type, and a fifth eyepiece lens of a positive optical focal length meniscus type, which are arranged in sequence from the object side to the observation side along the optical axis.

[0009] Furthermore, the side surfaces where the first lens of the objective lens and the second lens of the objective lens are connected are glued together, the side surfaces where the first lens of the eyepiece and the second lens of the eyepiece are connected are glued together, and the side surfaces where the third lens of the eyepiece and the fourth lens of the eyepiece are connected are glued together.

[0010] Furthermore, the fourth lens of the objective lens is movably arranged along the optical axis direction, and focusing from infinity to 3 meters can be achieved by moving the fourth lens of the objective lens back and forth along the optical axis direction.

[0011] Furthermore, the magnification of the binoculars is 10 times.

[0012] Furthermore, the exit pupil diameter of the binoculars ranges from 3.5 mm to 4.5 mm.

[0013] Furthermore, the pupil distance of the binoculars ranges from 15 mm to 18 mm.

[0014] Furthermore, the field of view angle of the binoculars ranges from 6° to 6.5°.

[0015] Furthermore, the aperture range of the first lens of the objective lens is 30mm-50mm.

[0016] Furthermore, the total length of the optical system of the binoculars does not exceed 130 mm.

[0017] The technical solution of the utility model has the following advantages: the binoculars achieve high resolution in the center of the field of view and the large field of view, and can see clear images. At the same time, the use of multiple sets of glued lenses and low-dispersion glass can greatly reduce chromatic aberration. In addition, the use of a prism combination of a semi-pentaprism and a roof prism greatly shortens the overall length of the binoculars, making them more convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 1 is an optical structure diagram of the optical system of the binoculars in the embodiment of the utility model.

[0020] Explanation of the accompanying reference numerals: 1, objective lens group; L1I, first lens of objective lens; L12, second lens of objective lens; L13, third lens of objective lens; L14, fourth lens of objective lens; 2, Behan prism group; L2I, half pentaprism; L22, roof prism; 3, real image plane of objective lens; 4, eyepiece group; L4I, first lens of eyepiece; L42, second lens of eyepiece; L43, third lens of eyepiece; L44, fourth lens of eyepiece; L45, fifth lens of eyepiece. DETAILED DESCRIPTION

[0021] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0023] The embodiment of the utility model provides a pair of binoculars, which is used to magnify distant objects through an optical system so that the objects can enter human eyes, making detailed observation clearer.

[0024] refer to Figure 1 As shown, the optical system of the binoculars includes an objective lens group 1, a Pehan prism group 2, an objective lens real image surface 3, and an eyepiece group 4 which are arranged in sequence from the object side to the observation side in the direction of the optical axis.

[0025] The objective lens group 1 includes a first objective lens L11 of a positive power biconvex type, a second objective lens L12 of a negative power meniscus type, a third objective lens L13 of a positive power meniscus type, and a fourth objective lens L14 of a negative power meniscus type. The fourth objective lens L14 is movably arranged along the optical axis, and the fourth objective lens L14 can be moved forward and backward along the optical axis to achieve focusing from infinity to 3 meters.

[0026] The Behan prism group 2 includes a half pentaprism L21 and a roof prism L22. The Behan prism group 2 greatly shortens the total optical length of the entire optical system, and enables the image formed by the light from the distant object after passing through the objective lens group 1 to be flipped and imaged on the real image surface 3 of the objective lens.

[0027] The eyepiece group 4 includes a first eyepiece lens L41 of a negative power biconcave type, a second eyepiece lens L42 of a positive power biconvex type, a third eyepiece lens L43 of a positive power biconvex type, a fourth eyepiece lens L44 of a negative power meniscus type, and a fifth eyepiece lens L45 of a positive power meniscus type. The eyepiece group 4 is used to magnify the real image surface 3 of the objective lens, and finally the human eye can see an object with a magnification of 10 times.

[0028] Among them, the side surfaces of the objective lens first lens L11 and the objective lens second lens L12 are glued together, the side surfaces of the eyepiece first lens L41 and the eyepiece second lens L42 are glued together, and the side surfaces of the eyepiece third lens L43 and the eyepiece fourth lens L44 are glued together. The gluing of positive and negative lenses can greatly improve the chromatic aberration problem of the telescope. At the same time, the total length of the overall optical system is shortened after the lenses are glued.

[0029] Among them, the field of view angle of the binoculars ranges from 6° to 6.5°, the exit pupil diameter ranges from 3.5mm to 4.5mm, and the exit pupil distance ranges from 15mm to 17mm. The longer exit pupil distance makes it easier for different groups of people to use.

[0030] The aperture range of the first objective lens L11 is 30mm-50mm, and the total length of the optical system of the binoculars does not exceed 130mm. The small-volume binoculars embody the convenience of use.

[0031] Table 1 below lists the actual parameters of each lens of this embodiment that meets the above characteristics:

[0032]

[0033]

[0034] Table 1

[0035] The air spacing parameters of binoculars vary as shown in Table 2:

[0036] Object distance Infinity 3 meters D(5) 40.15 43.11 D(7) 10.75 7.79

[0037] Table 2

[0038] Wherein, D(5) is the central air gap between the objective lens third lens L13 and the objective lens fourth lens L14 in the optical axis direction; D(7) is the central air gap between the objective lens fourth lens L14 and the Bihan prism group 2 in the optical axis direction.

[0039] In summary, this type of binoculars has the following advantages:

[0040] First, the binoculars have achieved high resolution in the center of the field of view and in the large field of view. At the same time, they use multiple groups of cemented lenses and low-dispersion glass to greatly reduce chromatic aberration.

[0041] Second, the overall structure is compact, with the advantages of small size and light weight;

[0042] Third, the prism combination of half pentaprism and roof prism is adopted, which greatly shortens the overall length of the binoculars and makes them more convenient.

[0043] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. A pair of binoculars, characterized in that: It comprises an objective lens group (1), a Pehan prism group (2), and an eyepiece group (4) which are arranged in sequence from the object side to the observation side along the optical axis direction; The objective lens group (1) comprises a first objective lens (L11) of a positive focal power biconvex type, a second objective lens (L12) of a negative focal power meniscus type, a third objective lens (L13) of a positive focal power meniscus type, and a fourth objective lens (L14) of a negative focal power meniscus type, which are arranged in sequence from the object side to the observation side along the optical axis; The Behan prism group (2) comprises a half pentaprism (L21) and a roof prism (L22) which are arranged in sequence from the object side to the observation side along the optical axis direction; The eyepiece group (4) comprises a first eyepiece lens (L41) of a negative optical focal length biconcave type, a second eyepiece lens (L42) of a positive optical focal length biconvex type, a third eyepiece lens (L43) of a positive optical focal length biconvex type, a fourth eyepiece lens (L44) of a negative optical focal length meniscus type, and a fifth eyepiece lens (L45) of a positive optical focal length meniscus type, which are sequentially arranged along the optical axis from the object side to the observation side.

2. The binoculars according to claim 1, characterized in that: The side surfaces where the first lens (L11) of the objective lens and the second lens (L12) of the objective lens are connected are glued together, the side surfaces where the first lens (L41) of the eyepiece and the second lens (L42) of the eyepiece are connected are glued together, and the side surfaces where the third lens (L43) of the eyepiece and the fourth lens (L44) of the eyepiece are connected are glued together.

3. The binoculars according to claim 1, characterized in that: The fourth lens (L14) of the objective lens is movably arranged along the optical axis direction, and focusing from infinity to 3 meters is achieved by moving the fourth lens (L14) of the objective lens forward and backward along the optical axis direction.

4. The binoculars according to claim 1, characterized in that: The binoculars have a magnification of 10 times.

5. The binoculars according to claim 1, characterized in that: The exit pupil diameter of the binoculars ranges from 3.5 mm to 4.5 mm.

6. The binoculars according to claim 1, characterized in that: The pupil distance of the binoculars ranges from 15 mm to 18 mm.

7. The binoculars according to claim 1, characterized in that: The field of view angle of the binoculars is in the range of 6° to 6.5°.

8. The binoculars according to claim 1, characterized in that: The aperture range of the first lens (L11) of the objective lens is 30mm-50mm.

9. The binoculars according to claim 1, characterized in that: The total length of the optical system of the binoculars does not exceed 130 mm.

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