CN218675478U - Zoom optical system and monitoring image pickup apparatus - Google Patents

Abstract

The utility model discloses an optical system and surveillance camera equipment zoom, optical system zooms includes a plurality of battery of lens that are arranged in proper order by the thing side to picture side, and is a plurality of correspond between the battery of lens and form an optical axis, wherein, it is a plurality of the battery of lens includes first battery of lens and second battery of lens, wherein, first battery of lens with the second battery of lens is followed respectively the mobile setting of extending direction of optical axis. The image plane compensation is realized by offsetting the conjugate distance change amount of the first lens group with the conjugate distance change amount of the second lens group after longitudinal amplification, and when the total optical length of the zoom optical system is controlled to be less than 45mm by the material, the refractive index, the Abbe number, the curvature and the core thickness of each lens in the first lens group and the second lens group, the magnification of the zoom optical system can be 4x, so that the problems of large volume and small magnification of the conventional zoom optical system are solved.

Description

Zoom optical system and monitoring image pickup apparatus

Technical Field

The utility model relates to the field of optical technology, especially, relate to optical system and surveillance camera equipment zoom.

Background

The zoom optical system for monitoring generally has the defects of large volume, small multiplying power under the condition of the same total length, incapability of ensuring infrared confocal of each multiplying power in the zooming process, obvious reduction of lens resolution in high-temperature and low-temperature (the temperature is 70 ℃ and minus 40 ℃) environments and the like. Most lenses in the market at present are large in size and small in magnification, so that popularization of the lenses in specific environments is affected.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an optical system and surveillance camera equipment zoom aims at solving the current problem that optical system is bulky and the multiplying power is little that zooms.

To achieve the above object, the present invention provides a zoom optical system, wherein the zoom optical system includes a plurality of lens groups arranged in sequence from an object side to an image side, and a plurality of the lens groups correspond to each other to form an optical axis therebetween, and wherein the plurality of lens groups include:

a first lens group including a first lens, a second lens, a third lens, and a fourth lens arranged in order from an object side to an image side; and the number of the first and second groups,

a second lens group including a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens arranged in order from an object side to an image side;

the first lens group and the second lens group are movably arranged along the extending direction of the optical axis respectively, and the total optical length of the zooming optical system is controlled to be less than 45mm through the material, the refractive index, the Abbe number, the curvature and the core thickness of each lens in the first lens group and the second lens group, so that the magnification of the zooming optical system is 4x.

Optionally, the first lens, the third lens, the fourth lens, the fifth lens, the seventh lens, and the tenth lens are made of glass.

Optionally, the second lens, the sixth lens, the eighth lens, the ninth lens, and the eleventh lens are made of plastic.

Optionally, the first lens, the third lens, the fourth lens, the seventh lens, and the tenth lens are all spherical mirrors.

Optionally, the second lens, the fifth lens, the sixth lens, the eighth lens, the ninth lens, and the eleventh lens are all aspheric lenses.

Optionally, the focal power of the first lens group is negative, and the focal power of the second lens group is positive.

Optionally, the focal power of the fifth lens is positive, the focal power of the sixth lens is negative or positive, the focal power of the seventh lens is positive, the focal power of the eighth lens is negative, the focal power of the ninth lens is positive, the focal power of the tenth lens is negative, and the focal power of the eleventh lens is negative or positive.

Optionally, the third lens and the fourth lens are cemented.

Optionally, a diaphragm is arranged between the first lens group and the second lens group, a distance between one side of the first lens group facing the image side and the diaphragm is L1, wherein L1 is greater than or equal to 0.83mm and less than or equal to 10.02mm, and a distance between one side of the second lens group facing the object side and the diaphragm is L2, wherein L2 is greater than or equal to 0.35mm and less than or equal to 8.894mm; and/or the presence of a gas in the gas,

the zoom optical system further comprises a photosensitive chip, the photosensitive chip is arranged on one side, facing the image side, of the second lens group, and a photosensitive surface of the photosensitive chip is arranged facing the second lens group; and/or the presence of a gas in the gas,

and an optical filter is arranged between the photosensitive chip and the second lens group.

The utility model provides a surveillance camera equipment, surveillance camera equipment include the optical system that zooms, the optical system that zooms includes a plurality of battery of lens that arrange in proper order by the thing side to picture side, and is a plurality of it forms an optical axis, wherein, a plurality of to correspond between the battery of lens includes:

a first lens group including a first lens, a second lens, a third lens, and a fourth lens arranged in order from an object side to an image side; and (c) a second step of,

a second lens group including a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens arranged in order from an object side to an image side;

the first lens group and the second lens group are movably arranged along the extending direction of the optical axis respectively, and the total optical length of the zooming optical system is controlled to be less than 45mm through the material, the refractive index, the Abbe number, the curvature and the core thickness of each lens in the first lens group and the second lens group, so that the magnification of the zooming optical system is 4x.

The utility model provides an among the technical scheme, first battery of lens and second battery of lens are respectively along the mobile setting of extending direction of optical axis, through the conjugate distance variation of first battery of lens with conjugate distance variation after the vertical enlargeing of second battery of lens offsets, realizes image plane compensation, and passes through first battery of lens with the material, refracting index, abbe number, camber and the core of each lens in the second battery of lens are thick, right zoom optical system's optical overall length control when being less than 45mm, can realize zoom optical system's multiplying power is 4x to solve current zoom optical system and bulky and the little problem of multiplying power.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a schematic perspective view of an embodiment of a zoom optical system provided by the present invention.

The reference numbers indicate:

reference numerals	Name (R)	Reference numerals	Name (R)
				1000	Zoom optical system	7	Seventh lens element
100	First lens group	8	Eighth lens element
				1	First lens	9	Ninth lens
2	Second lens	10	Tenth lens
				3	Third lens	11	Eleventh lens
4	Fourth lens	30	Diaphragm
				200	Second lens group	40	Photosensitive chip
5	Fifth lens element	50	Optical filter
				6	Sixth lens element

The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without making creative efforts belong to the protection scope of the present invention.

It should be noted that, if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description relating to "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

At present, a zoom optical system for monitoring generally has the defects of large volume, small multiplying power under the condition of the same total length, incapability of ensuring infrared confocal of each multiplying power in a zoom process, obvious reduction of lens resolution in high-temperature and low-temperature (70 ℃ and-40 ℃) environments and the like. Most lenses in the market at present are large in size and small in magnification, so that popularization of the lenses in specific environments is affected.

In order to solve the above problem, the present invention provides a zoom optical system 1000, and fig. 1 shows an embodiment of the zoom optical system 1000.

Referring to fig. 1, the zoom optical system 1000 includes a plurality of lens groups arranged in order from an object side to an image side, and an optical axis is correspondingly formed between the plurality of lens groups, wherein the plurality of lens groups includes a first lens group 100 and a second lens group 200, and the first lens group 100 includes a first lens 1, a second lens 2, a third lens 3 and a fourth lens 4 arranged in order from the object side to the image side; the second lens group 200 includes a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, and an eleventh lens 11 arranged in order from the object side to the image side; the first lens group 100 and the second lens group 200 are movably disposed along an extending direction of the optical axis, and when the total optical length of the zoom optical system 1000 is controlled to be less than 45mm, the magnification of the zoom optical system 1000 can be 4x by controlling the material, refractive index, abbe number, curvature and core thickness of each lens in the first lens group 100 and the second lens group 200.

The utility model provides an among the technical scheme, first battery of lens 100 and second battery of lens 200 are respectively along the mobile setting of extending direction of optical axis, through the conjugate distance variation of first battery of lens 100 with conjugate distance variation after second battery of lens 200 vertically enlargies offsets, realizes image plane compensation, and passes through first battery of lens 100 with material, refracting index, abbe number, camber and the core thickness of each lens in the second battery of lens 200, through rational distribution lens focal power, adjustment glass shape and material collocation, effective achromatism and second grade spectrum make the spherical aberration on each lens, coma, astigmatism etc. compensate and offset to reach the effect of clear formation of image, make zoom optical system 1000's optical total length control when being less than 45mm, can realize zoom optical system 1000's multiplying power is 4x to can realize the confocal of visible wave band and infrared band, guarantee the formation of image of each multiplying power visible wave band and infrared band clear, in order to solve current zoom optical system 1000 bulky and the problem that the multiplying power is little.

Specifically, in consideration of the influence of temperature change, the glass lens has the characteristics of high hardness, strong wear resistance and long service life. And the all-glass lens has stable chemical properties, is not easy to be affected by thermal expansion and cold contraction to cause the phenomenon of coke leakage, and is not easy to be corroded. The full-glass lens can well resist the problem of lens thermal deformation, and can keep the high precision of the lens for a long time. Therefore, in this embodiment, the first lens 1, the third lens 3, the fourth lens 4, the fifth lens 5, the seventh lens 7, and the tenth lens 10 are made of glass.

Specifically, in order to reduce the weight of the zoom optical system 1000 and reduce the control cost, in this embodiment, the second lens 2, the sixth lens 6, the eighth lens 8, the ninth lens 9, and the eleventh lens 11 are made of plastic. With such an arrangement, the zoom optical system 1000 has the advantages of good impact resistance, and good weathering and ultraviolet radiation resistance.

Through the matching of the glass material and the plastic material, the zoom optical system 1000 can ensure that the lens still has enough definition in high and low temperature environments (high temperature 70 ℃ and low temperature-40 ℃) under the condition of high and low temperature change in practical use and under the condition of focusing at normal temperature of 20 ℃.

Specifically, in the present embodiment, the first lens 1, the third lens 3, the fourth lens 4, the seventh lens 7, and the tenth lens 10 are all spherical mirrors. Because the reflection of the spherical lens obeys the reflection law of light, the light is converged or diverged, and the spherical aberration correction can be carried out by the aspheric lens.

Specifically, in the present embodiment, the second lens 2, the fifth lens 5, the sixth lens 6, the eighth lens 8, the ninth lens 9, and the eleventh lens 11 are all aspheric lenses. By arranging the aspherical mirror, the spherical aberration, coma aberration, astigmatism, distortion and the like generated by the image of the light transmitted by the spherical mirror can be corrected, the deflection angle of the light can be reduced, the light of the system is smoother, the sensitivity of the installation and adjustment tolerance of the lens is reduced, the problems of distortion of the visual field and the like are solved, and the aspherical mirror enables the lens to be lighter, thinner and flatter and still maintain excellent shock resistance.

Further, in the optical design process, the functions and tasks achieved by the lens group are grouped, and the focal power of the first lens group 100 is negative; the focal power of the second lens group 200 is positive, wherein the focal power of the fifth lens 5 is positive, the focal power of the sixth lens 6 is negative or positive, the focal power of the seventh lens 7 is positive, the focal power of the eighth lens 8 is negative, the focal power of the ninth lens 9 is positive, the focal power of the tenth lens 10 is negative, and the focal power of the eleventh lens 11 is negative or positive. By the arrangement, the optimal correction of high-order aberration and chromatic aberration is realized, and meanwhile, vignetting is arranged, so that peripheral stray light is blocked under the condition that the illumination is not influenced, and the center and the edge of the image surface can meet the same resolution requirement.

The surface shape of any one of the above lenses needs to satisfy the following formula:

wherein c corresponds to the reciprocal of the radius R, y is the radial coordinate, k is the conic coefficient, a ₁ To a ₈ The coefficients are respectively corresponding to the radial coordinates.

It should be noted that the basic parameter table of the zoom optical system in this embodiment is shown in table 1, where the radius of curvature and the thickness are both in millimeters (mm).

TABLE 1

The aspherical coefficients of the respective surfaces are shown in table 2:

TABLE 2

Further, in order to improve the image quality of the optical system, reduce the light energy loss, increase the image definition, protect the scale surface, and further optimize the processing flow to meet the design requirement, in this embodiment, the third lens 3 and the fourth lens 4 are connected by gluing. The reasonable use of the cementing part, the proper distribution of focal power, the combination of the thermal parameters of the glass material, the good correction of aberration and the realization of the effect of high-low temperature athermalization, and the effective reduction of chromatic aberration makes it reach the effects of a visible light wave band and a near-infrared wave band imaging confocal plane and simultaneously clear, and meets the day and night sharing requirements.

Further, in order to improve the imaging quality, in the present embodiment, a stop 30 is disposed between the first lens group 100 and the second lens group 200. The diaphragm 30 limits the light beam aperture on the axis to block part of light rays in the zooming process, so that light spots are reduced, the image contrast is improved, and the image quality is improved.

Specifically, in order to specifically control the movable ranges of the first lens group 100 and the second lens group 200, in the present embodiment, the distance between the side of the first lens group 100 facing the image side and the stop 30 is L1, wherein 0.83mm ≦ L1 ≦ 10.02mm, and the distance between the side of the second lens group 200 facing the object side and the stop 30 is L2, wherein 0.35mm ≦ L2 ≦ 8.894mm. It should be noted that the two related technical features may be set at the same time or alternatively.

Specifically, in this embodiment, the zoom optical system further includes a photosensitive chip 40, the photosensitive chip 40 is disposed on a side of the second lens group 200 facing the image side, and a photosensitive surface of the photosensitive chip 40 is disposed facing the second lens group 200, so as to receive the object image on the image side, and the received object image is processed by the photosensitive chip 40.

Further, an optical filter 50 is disposed between the photosensitive chip 40 and the second lens group 200. The optical filter 50 can effectively filter stray light in a non-working waveband, so that optical noise is reduced, and difficulty in subsequent photoelectric module processing is reduced. The filter 50 can also be used to adjust the color saturation of the object image when it is finally imaged.

In the zoom optical system 1000, since the third lens 3 and the fourth lens 4 are bonded lenses, chromatic aberration of the lens can be effectively corrected, and infrared confocal is realized under the condition of controlling purple sides of the lens; the second lens 2 is a meniscus lens, and the meniscus shape of the plastic aspheric lens of the second lens 2 can reduce the lens distortion; meanwhile, the lens is matched with the first lens 1, and the chromatic aberration, the spherical aberration and the sine aberration at a high power position can be further corrected by the similar adhesion effect. The lenses of the second lens group 200 are matched, a glass aspheric lens is used behind the diaphragm 30, the aberration of the emergent light of the diaphragm 30 can be corrected, the stability of the resolution of the high-low temperature lens is ensured, the fifth lens 5 is a meniscus lens, and the meniscus shape of the fifth lens 5 can further reduce the distortion; and then, the arrangement of the rear lens is combined to form a perfect similar cemented structure (namely, the matching of negative, positive, negative and positive lenses of the focal powers of the sixth lens 6 to the eleventh lens 11 behind the diaphragm 30), so that the optimal correction of high-order aberration and chromatic aberration is realized. Meanwhile, each lens is provided with vignetting, so that peripheral stray light is blocked under the condition of not influencing illumination, and the center and the edge of the image surface guarantee the same resolution requirements.

Therefore, in order to realize the resolution definition of the system in high and low temperature environments (high temperature is 70 ℃, low temperature is 40 ℃ below zero), the system adopts a plastic material with small difference of high and low temperature corresponding refractive indexes, considers the variation of the refractive indexes and Abbe numbers of various lens materials, matches the surface type and the air interval variation, and ensures the positive and negative collocation of the variation of each element in the high and low temperature environments, thereby realizing the synchronization and the definition of the image surface in the high and low temperature environments.

The utility model relates to a monitoring camera equipment, monitoring camera equipment includes foretell zoom optical system, because monitoring camera equipment includes zoom optical system, this zoom optical system's specific structure refers to above-mentioned embodiment, because this monitoring camera equipment's zoom optical system has adopted the whole technical scheme of above-mentioned all embodiments, consequently has all beneficial effects that the technical scheme of above-mentioned embodiment brought at least, and here is not repeated repeatedly one by one again.

The above only be the preferred embodiment of the utility model discloses a not consequently restriction the utility model discloses a patent range, all are in the utility model discloses a conceive, utilize the equivalent structure transform of what the content was done in the description and the attached drawing, or direct/indirect application all is included in other relevant technical field the utility model discloses a patent protection within range.

Claims (10)

1. A zoom optical system comprising a plurality of lens groups arranged in order from an object side to an image side, the plurality of lens groups corresponding to each other to form an optical axis, wherein the plurality of lens groups comprises:

a first lens group including a first lens, a second lens, a third lens, and a fourth lens arranged in order from an object side to an image side; and the number of the first and second groups,

a second lens group including a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, and an eleventh lens arranged in order from an object side to an image side;

the first lens group and the second lens group are movably arranged along the extension direction of the optical axis respectively, and when the total optical length of the zooming optical system is controlled to be less than 45mm through the material, the refractive index, the Abbe number, the curvature and the core thickness of each lens in the first lens group and the second lens group, the multiplying power of the zooming optical system can be 4x.

2. The zoom optical system according to claim 1, wherein the first lens, the third lens, the fourth lens, the fifth lens, the seventh lens, and the tenth lens are made of glass.

3. The zoom optical system according to claim 1, wherein the second lens, the sixth lens, the eighth lens, the ninth lens, and the eleventh lens are made of plastic.

4. The zoom optical system of claim 1, wherein the first lens, the third lens, the fourth lens, the seventh lens, and the tenth lens are all spherical mirrors.

5. The zoom optical system of claim 1, wherein the second lens, the fifth lens, the sixth lens, the eighth lens, the ninth lens, and the eleventh lens are each aspherical mirrors.

6. The zoom optical system of claim 1, wherein the optical power of the first lens group is negative and the optical power of the second lens group is positive.

7. The zoom optical system according to claim 6, wherein an optical power of the fifth lens is positive, an optical power of the sixth lens is negative or positive, an optical power of the seventh lens is positive, an optical power of the eighth lens is negative, an optical power of the ninth lens is positive, an optical power of the tenth lens is negative, and an optical power of the eleventh lens is negative or positive.

8. The zoom optical system of claim 1, wherein the third lens and the fourth lens are cemented.

9. The zoom optical system according to claim 8, wherein a stop is disposed between the first lens group and the second lens group, a distance between a side of the first lens group facing the image side and the stop is L1, wherein 0.83mm ≦ L1 ≦ 10.02mm, a distance between a side of the second lens group facing the object side and the stop is L2, wherein 0.35mm ≦ L2 ≦ 8.894mm; and/or the presence of a gas in the gas,

the zoom optical system further comprises a photosensitive chip, the photosensitive chip is arranged on one side, facing the image side, of the second lens group, and a photosensitive surface of the photosensitive chip is arranged facing the second lens group; and/or the presence of a gas in the gas,

and an optical filter is arranged between the photosensitive chip and the second lens group.

10. A monitoring image pickup apparatus characterized by comprising the zoom optical system according to any one of claims 1 to 9.

Images