Video zoom optical lens

Abstract

The invention discloses a video zoom optical lens which is composed of a transmission group G1 with positive focal power, a transmission group G2 with negative focal power, an aperture diaphragm, a transmission group G3 with positive focal power, a transmission group G4 with positive focal power, an optical filter and an image plane which are sequentially arranged from an object space to an image space. The focal length can be changed through the movement of the transmission group G2 along the optical axis, and a position can be found through the matched movement of the transmission group G4 along the optical axis, so that the image surface position of the optical system is unchanged, and the imaging is clear. Compared with the prior art, the video zoom optical lens of the technical scheme can simultaneously realize clear imaging under the condition of matching a large image plane, so that the product performance and the appearance size are well matched, and the video zoom optical lens can be widely applied to the technical fields of video conferences and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of optical lenses, and in particular relates to a video zoom optical lens. Background Art

[0002] With the continuous development and progress of communication and video technology, in order to reduce the operating costs of enterprises, high-quality video conferencing systems have become an indispensable part of people's work and life. With the increasing size of chips and the decreasing size of pixels, the demand for high-quality and high-performance video conferencing systems is becoming more and more widespread. However, the existing video zoom optical lenses have the disadvantages of poor imaging quality and a small corresponding image surface. Therefore, there is an urgent need for a video zoom optical lens that can achieve the function of clear imaging while matching a large image surface. Summary of the invention

[0003] In order to overcome the above-mentioned shortcomings, the inventor of the present invention has continuously reformed and innovated through long-term exploration and attempts, multiple experiments and efforts, and proposed a video zoom optical lens, which can change the focal length by moving the transmission group G2 along the optical axis, and can find a position by coordinating the movement of the transmission group G4 along the optical axis, so that the image plane position of the optical system remains unchanged and the image is clear. Compared with the prior art, the video zoom optical lens of the technical solution can achieve clear imaging while matching the large image plane, so that the product performance and appearance size are well matched, and can be widely used in technical fields such as video conferencing.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is to provide a video zoom optical lens. It is composed of a transmission group G1 with positive focal length, a transmission group G2 with negative focal length, an aperture stop, a transmission group G3 with positive focal length, a transmission group G4 with positive focal length, a filter and an image plane, which are arranged in sequence from the object side to the image side. The transmission group G1 is composed of a first lens, a second lens and a third lens arranged in sequence from the object side to the image side, wherein the second lens and the third lens are positive lenses, and the first lens is a negative lens; The transmission group G2 is composed of a fourth lens, a fifth lens and a sixth lens arranged in sequence from the object side to the image side, wherein the sixth lens is a positive lens, and the fourth lens and the fifth lens are negative lenses; The transmission group G3 is composed of a seventh lens, an eighth lens and a ninth lens arranged in sequence from the object side to the image side, wherein the seventh lens and the eighth lens are positive lenses, and the ninth lens is a negative lens; The transmission group G4 consists of a tenth lens, an eleventh lens and a twelfth lens which are sequentially arranged from the object side to the image side, wherein the tenth lens and the eleventh lens are positive lenses, and the twelfth lens is a negative lens.

[0005] According to the video zoom optical lens of the present invention, a further preferred technical solution is: in the short focal position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (8.27, 8.62), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-1.78, -1.33), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (3.26, 5.13), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (3.27, 4.59); At the mid-focus position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (1.35, 2.01), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-0.66, -0.23), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (0.61, 1.11), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (0.58, 1.16); At the telephoto position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (0.69, 1.22), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-0.33, -0.09), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (0.21, 0.56), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (0.39, 0.50).

[0006] According to the video zoom optical lens of the present invention, a further preferred technical solution is: The surface of the first lens facing the object plane is convex, and the surface facing the image plane is concave; The surface of the second lens facing the object plane is convex, and the surface facing the image plane is flat; The surface of the third lens facing the object plane is convex, and the surface facing the image plane is concave; The surface of the fourth lens element facing the object plane is concave, and the surface of the fourth lens element facing the image plane is concave; The surface of the fifth lens element facing the object plane is concave, and the surface of the fifth lens element facing the image plane is concave; The surface of the sixth lens facing the object plane is convex, and the surface facing the image plane is concave; The surface of the seventh lens element facing the object plane is convex, and the surface of the seventh lens element facing the image plane is convex; The surface of the eighth lens facing the object plane is convex, and the surface facing the image plane is convex; The surface of the ninth lens facing the object plane is concave, and the surface facing the image plane is concave; The surface of the tenth lens facing the object plane is convex, and the surface facing the image plane is convex; The surface of the eleventh lens facing the object plane is convex, and the surface facing the image plane is convex; The surface of the twelfth lens facing the object plane is concave, and the surface facing the image plane is concave.

[0007] According to the video zoom optical lens of the present invention, a further preferred technical solution is that the transmission group G2 and the transmission group G4 are moving groups, and the transmission group G1 and the transmission group G3 are fixed groups.

[0008] According to the video zoom optical lens described in the present invention, a further preferred technical solution is: the first lens and the second lens form a cemented lens group, the fifth lens and the sixth lens form a cemented lens group, the eighth lens and the ninth lens form a cemented lens group, and the eleventh lens and the twelfth lens form a cemented lens group.

[0009] According to the video zoom optical lens of the present invention, a further preferred technical solution is that the first to twelfth lenses are all spherical lenses.

[0010] Compared with the prior art, the technical solution of the present invention has the following advantages / benefits: In the video zoom optical lens of the present invention, the focal length is changed by moving the transmission group G2 along the optical axis, and a position can be found by the coordinated movement of the transmission group G4 along the optical axis, so that the image plane position of the optical system remains unchanged and the image is clear. Compared with the prior art, the video zoom optical lens of the present technical solution can achieve clear imaging while matching a large image plane, so that the product performance and appearance size are well matched, and can be widely used in technical fields such as video conferencing. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 The present invention is a structural schematic diagram of a video zoom optical lens.

[0013] Figure 2 This is a light fan diagram of a video zoom optical lens embodiment of the present invention at short focal length.

[0014] Figure 3 This is a light fan diagram of a video zoom optical lens embodiment of the present invention at mid-focus.

[0015] Figure 4 This is a light fan diagram of a video zoom optical lens embodiment of the present invention at a long focal length.

[0016] Figure 5 The figure is a point diagram of a video zoom optical lens embodiment of the present invention at short focal length.

[0017] Figure 6 The point diagram of a video zoom optical lens embodiment of the present invention at mid-focus.

[0018] Figure 7 The point diagram of a video zoom optical lens embodiment of the present invention at a telephoto focus.

[0019] The markings in the figure are: 1. first lens, 2. second lens, 3. third lens, 4. fourth lens, 5. fifth lens, 6. sixth lens, 7. seventh lens, 8. eighth lens, 9. ninth lens, 10. tenth lens, 11. eleventh lens, 12. twelfth lens, 13. filter, 14. image plane. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. Therefore, the detailed description of the embodiments of the present invention provided below is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention.

[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and thus, once an item is defined in one drawing, it may not be further defined or explained in the subsequent drawings.

[0022] Embodiment 1: like Figure 1 As shown, a video zoom optical lens is composed of a transmission group G1 with positive optical power, a transmission group G2 with negative optical power, an aperture stop, a transmission group G3 with positive optical power, a transmission group G4 with positive optical power, a filter and an image plane, which are arranged in sequence from the object side to the image side. The transmission group G1 is composed of a first lens, a second lens and a third lens arranged in sequence from the object side to the image side, wherein the second lens and the third lens are positive lenses, and the first lens is a negative lens; the surface of the first lens facing the object plane is a convex surface, and the surface facing the image plane is a concave surface; the surface of the second lens facing the object plane is a convex surface, and the surface facing the image plane is a flat surface; the surface of the third lens facing the object plane is a convex surface, and the surface facing the image plane is a concave surface; The transmission group G2 is composed of a fourth lens, a fifth lens and a sixth lens arranged in sequence from the object side to the image side, wherein the sixth lens is a positive lens, and the fourth lens and the fifth lens are negative lenses; the surface of the fourth lens facing the object plane is a concave surface, and the surface facing the image plane is a concave surface; the surface of the fifth lens facing the object plane is a concave surface, and the surface facing the image plane is a concave surface; the surface of the sixth lens facing the object plane is a convex surface, and the surface facing the image plane is a concave surface; The transmission group G3 is composed of a seventh lens, an eighth lens and a ninth lens arranged in sequence from the object side to the image side, wherein the seventh lens and the eighth lens are positive lenses, and the ninth lens is a negative lens; the surface of the seventh lens facing the object plane is a convex surface, and the surface facing the image plane is a convex surface; the surface of the eighth lens facing the object plane is a convex surface, and the surface facing the image plane is a convex surface; the surface of the ninth lens facing the object plane is a concave surface, and the surface facing the image plane is a concave surface; The transmission group G4 is composed of the tenth lens, the eleventh lens and the twelfth lens arranged in sequence from the object side to the image side, wherein the tenth lens and the eleventh lens are positive lenses, and the twelfth lens is a negative lens. The surface of the tenth lens facing the object plane is convex, and the surface facing the image plane is convex; the surface of the eleventh lens facing the object plane is convex, and the surface facing the image plane is convex; the surface of the twelfth lens facing the object plane is concave, and the surface facing the image plane is concave.

[0023] The transmission group G2 and the transmission group G4 are moving groups, and the transmission group G1 and the transmission group G3 are fixed groups. The focal length is changed by moving the transmission group G2 along the optical axis, and a position can be found by the coordinated movement of the transmission group G4 along the optical axis, so that the image plane position of the optical system remains unchanged and the image is clear.

[0024] The first lens and the second lens form a cemented lens group, the fifth lens and the sixth lens form a cemented lens group, the eighth lens and the ninth lens form a cemented lens group, and the eleventh lens and the twelfth lens form a cemented lens group. Of course, the cemented lens is a way of combining two lenses. The cementation of the present invention is only a combination means, and other similar reasonable means can be used.

[0025] The first to twelfth lenses are all spherical lenses. The lenses are spherical, which has low manufacturing costs and can significantly reduce their sales prices. They are easy for consumers to accept and have good sales prospects.

[0026] At the short focal position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (8.27, 8.62), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-1.78, -1.33), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (3.26, 5.13), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (3.27, 4.59); At the mid-focus position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (1.35, 2.01), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-0.66, -0.23), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (0.61, 1.11), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (0.58, 1.16); At the telephoto position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (0.69, 1.22), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-0.33, -0.09), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (0.21, 0.56), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (0.39, 0.50).

[0027] Embodiment 2: On the basis of Example 1, a video zoom optical lens is proposed herein, wherein the ratio of the focal length of the lens group G1 to the focal length of the entire optical system at short focus is 8.42, the ratio of the focal length of the lens group G1 to the focal length of the entire optical system at focus is 1.68, and the ratio of the focal length of the lens group G1 to the focal length of the entire optical system at long focus is 0.84.

[0028] The ratio of the focal length of lens group G2 to the focal length of the entire optical system at short focus is -1.57, the ratio of the focal length of lens group G2 to the focal length of the entire optical system at medium focus is -0.32, and the ratio of the focal length of lens group G2 to the focal length of the entire optical system at long focus is -0.16.

[0029] The ratio of the focal length of lens group G3 to the focal length of the entire optical system at short focus is 3.92, the ratio of the focal length of lens group G3 to the focal length of the entire optical system at medium focus is 0.78, and the ratio of the focal length of lens group G3 to the focal length of the entire optical system at long focus is 0.39.

[0030] The ratio of the focal length of lens group G4 to the focal length of the entire optical system at short focus is 4.28, the ratio of the focal length of lens group G4 to the focal length of the entire optical system at medium focus is 0.86, and the ratio of the focal length of lens group G4 to the focal length of the entire optical system at long focus is 0.42.

[0031] The physical parameters of each lens meet the data requirements shown in Table 1: Table 1 Physical parameters of each lens in this embodiment The optical system provided by a video zoom optical lens in this embodiment has the following optical technical indicators: Working band: 435 nm-656 nm; Focal length f: 6mm (W)-60 mm (T); Field of view: 69.3°(W)-6.7°(T); Maximum aperture: 28mm; Image size: 7mm.

[0032] Note: W stands for short focal length and T stands for long focal length.

[0033] like Figure 2-Figure 4 As shown in the figure, the ray fan diagram RayFan of the video zoom optical lens at short focus, medium focus and long focus are given respectively. In the figure, the unit of the legend is μm, ex: ray aberration x component, ey: ray aberration y component, px: entrance pupil x coordinate, py: entrance pupil y coordinate. It can be seen that the meridional aberration and sagittal aberration of the video zoom optical lens are both small within the full focal length.

[0034] like Figure 5-Figure 7 As shown in the figure, the spot diagrams of the video zoom optical lens at short focus, medium focus and long focus are given respectively, and the unit of the legend in the figure is μm. It can be seen that the image spot of the video zoom optical lens in the full spectrum and full field of view at short focus, medium focus and long focus is small.

[0035] In the description of the present invention, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0036] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0037] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A video zoom optical lens, characterized in that: The optical system is composed of a transmission group G1 with positive power, a transmission group G2 with negative power, an aperture stop, a transmission group G3 with positive power, a transmission group G4 with positive power, a filter and an image plane, which are sequentially arranged from the object side to the image side. The transmission group G1 is composed of a first lens, a second lens and a third lens sequentially arranged from the object side to the image side, wherein the second lens and the third lens are positive lenses, and the first lens is a negative lens. The transmission group G2 is composed of a fourth lens, a fifth lens and a sixth lens arranged in sequence from the object side to the image side, wherein the sixth lens is a positive lens, and the fourth lens and the fifth lens are negative lenses; the transmission group G3 is composed of a seventh lens, an eighth lens and a ninth lens arranged in sequence from the object side to the image side, wherein the seventh lens and the eighth lens are positive lenses, and the ninth lens is a negative lens; the transmission group G4 is composed of a tenth lens, an eleventh lens and a twelfth lens arranged in sequence from the object side to the image side, wherein the tenth lens and the eleventh lens are positive lenses, and the twelfth lens is a negative lens.

2. The video zoom optical lens according to claim 1, characterized in that: At the short focal position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (8.27, 8.62), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-1.78, -1.33), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (3.26, 5.13), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (3.27, 4.59); At the mid-focus position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (1.35, 2.01), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-0.66, -0.23), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (0.61, 1.11), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (0.58, 1.16); At the telephoto position, the ratio of the focal length of the transmission group G1 to the focal length of the entire optical system is in the range of (0.69, 1.22), the ratio of the focal length of the transmission group G2 to the focal length of the entire optical system is in the range of (-0.33, -0.09), the ratio of the focal length of the transmission group G3 to the focal length of the entire optical system is in the range of (0.21, 0.56), and the ratio of the focal length of the transmission group G4 to the focal length of the entire optical system is in the range of (0.39, 0.50).

3. The video zoom optical lens according to claim 1, characterized in that: The surface of the first lens facing the object plane is convex, and the surface facing the image plane is concave; The surface of the second lens facing the object plane is convex, and the surface facing the image plane is a plane; The surface of the third lens facing the object plane is convex, and the surface facing the image plane is concave; The surface of the fourth lens facing the object plane is concave, and the surface facing the image plane is concave; The surface of the fifth lens facing the object plane is concave, and the surface facing the image plane is concave; The surface of the sixth lens facing the object plane is convex, and the surface facing the image plane is concave; The surface of the seventh lens facing the object plane is convex, and the surface facing the image plane is convex; The surface of the eighth lens facing the object plane is convex, and the surface facing the image plane is convex; The surface of the ninth lens facing the object plane is concave, and the surface facing the image plane is concave; The surface of the tenth lens facing the object plane is convex, and the surface facing the image plane is convex; The surface of the eleventh lens facing the object plane is convex, and the surface facing the image plane is convex; The surface of the twelfth lens facing the object plane is concave, and the surface facing the image plane is concave.

4. The video zoom optical lens according to claim 1, characterized in that: The transmission group G2 and the transmission group G4 are moving groups, and the transmission group G1 and the transmission group G3 are fixed groups.

5. The video zoom optical lens according to claim 1, characterized in that: The first lens and the second lens form a cemented lens group, the fifth lens and the sixth lens form a cemented lens group, the eighth lens and the ninth lens form a cemented lens group, and the eleventh lens and the twelfth lens form a cemented lens group.

6. The video zoom optical lens according to claim 1, characterized in that: The first to twelfth lenses are all spherical lenses.

Images