A video zoom optical lens

Abstract

The present invention discloses a video zoom optical lens, which is composed of a transmissive group G1 with positive optical power, a transmissive group G2 with negative optical power, an aperture stop, a transmissive group G3 with positive optical power, a transmissive group G4 with positive optical power, a filter, and an image plane, which are sequentially arranged from the object side to the image side. The focal length can be changed by moving the transmissive group G2 along the optical axis, and at the same time, a position can be found through the coordinated movement of the transmissive group G4 along the optical axis, so that the image plane position of the optical system remains unchanged and the imaging is clear. Compared with the prior art, the video zoom optical lens of the present technical solution can achieve clear imaging while matching the condition of a large image plane, so that the product performance and the appearance size are well matched, and thus it can be widely applied to technical fields such as video conferencing.

Description

Technical Field

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

[0002] With the continuous development and progress of communication and video technologies, 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. Along 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 increasingly widespread. However, the existing video zoom optical lenses have the deficiencies of poor imaging quality and relatively small corresponding image planes. 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 plane. Summary of the Invention

[0003] To overcome the above-mentioned deficiencies, the inventor of the present invention has conducted long-term exploration and attempts, as well as multiple experiments and efforts, continuously reforming and innovating, and proposed a video zoom optical lens. It can change the focal length by moving the transmission group G2 along the optical axis, and at the same time, it can find a position through the cooperative movement of the transmission group G4 along the optical axis to keep the image plane position of the optical system unchanged and achieve clear imaging. 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 thus it can be widely applied to technical fields such as video conferencing.

[0004] The technical solution adopted by the present invention to achieve the above object is: to provide a video zoom optical lens, which 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 sequentially arranged from the object side to the image side.

[0005] 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;

[0006] 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;

[0007] 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;

[0008] 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. Among them, the tenth lens and the eleventh lens are positive lenses, and the twelfth lens is a negative lens.

[0009] For a video zoom optical lens according to the present invention, a further preferred technical solution is that when in the short focal position, the ratio range of the focal length of the transmission group G1 to the focal length of the entire optical system is (8.27, 8.62), the ratio range of the focal length of the transmission group G2 to the focal length of the entire optical system is (-1.78, -1.33), the ratio range of the focal length of the transmission group G3 to the focal length of the entire optical system is (3.26, 5.13), and the ratio range of the focal length of the transmission group G4 to the focal length of the entire optical system is (3.27, 4.59);

[0010] When in the medium focal position, the ratio range of the focal length of the transmission group G1 to the focal length of the entire optical system is (1.35, 2.01), the ratio range of the focal length of the transmission group G2 to the focal length of the entire optical system is (-0.66, -0.23), the ratio range of the focal length of the transmission group G3 to the focal length of the entire optical system is (0.61, 1.11), and the ratio range of the focal length of the transmission group G4 to the focal length of the entire optical system is (0.58, 1.16);

[0011] When in the long focal position, the ratio range of the focal length of the transmission group G1 to the focal length of the entire optical system is (0.69, 1.22), the ratio range of the focal length of the transmission group G2 to the focal length of the entire optical system is (-0.33, -0.09), the ratio range of the focal length of the transmission group G3 to the focal length of the entire optical system is (0.21, 0.56), and the ratio range of the focal length of the transmission group G4 to the focal length of the entire optical system is (0.39, 0.50).

[0012] For a video zoom optical lens according to the present invention, a further preferred technical solution is:

[0013] The surface of the first lens facing the object surface is convex, and the surface facing the image surface is concave;

[0014] The surface of the second lens facing the object surface is convex, and the surface facing the image surface is flat;

[0015] The surface of the third lens facing the object surface is convex, and the surface facing the image surface is concave;

[0016] The surface of the fourth lens facing the object surface is concave, and the surface facing the image surface is concave;

[0017] The surface of the fifth lens facing the object surface is concave, and the surface facing the image surface is concave;

[0018] The surface of the sixth lens facing the object surface is convex, and the surface facing the image surface is concave;

[0019] The surface of the seventh lens facing the object surface is convex, and the surface facing the image surface is convex;

[0020] The surface of the eighth lens facing the object surface is convex, and the surface facing the image surface is convex;

[0021] The surface of the ninth lens facing the object surface is concave, and the surface facing the image surface is concave;

[0022] The surface of the tenth lens facing the object surface is convex, and the surface facing the image surface is convex;

[0023] The surface of the eleventh lens facing the object surface is convex, and the surface facing the image surface is convex;

[0024] The surface of the twelfth lens facing the object surface is concave, and the surface facing the image surface is concave.

[0025] For a video zoom optical lens according to 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.

[0026] For a video zoom optical lens according to the present invention, a further preferred technical solution is 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.

[0027] For a video zoom optical lens according to the present invention, a further preferred technical solution is that: the first to twelfth lenses are all spherical lenses.

[0028] Compared with the prior art, the technical solution of the present invention has the following advantages / beneficial effects:

[0029] In the video zoom optical lens of the present invention, the focal length is changed by the movement of the transmission group G2 along the optical axis. At the same time, a position can be found through the cooperative movement of the transmission group G4 along the optical axis, so that the image plane position of the optical system remains unchanged and the imaging is clear. Compared with the prior art, the video zoom optical lens of this technical solution can achieve clear imaging while matching the large image plane condition, so that the product performance and the appearance size are well matched, and thus it can be widely applied to technical fields such as video conferencing. Description of the Drawings

[0030] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for the embodiments will be briefly introduced below. It should be understood that the following accompanying drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related accompanying drawings can also be obtained based on these drawings.

[0031] Figure 1 It is a schematic structural diagram of a video zoom optical lens of the present invention.

[0032] Figure 2 It is a fan diagram of the short focal length of an embodiment of the video zoom optical lens of the present invention.

[0033] Figure 3 It is a fan diagram of the medium focal length of an embodiment of the video zoom optical lens of the present invention.

[0034] Figure 4 It is a fan diagram of the long focal length of an embodiment of the video zoom optical lens of the present invention.

[0035] Figure 5 It is a spot diagram of the short focal length of an embodiment of the video zoom optical lens of the present invention.

[0036] Figure 6 It is a spot diagram of the medium focal length of an embodiment of the video zoom optical lens of the present invention.

[0037] Figure 7 It is a spot diagram of the long focal length of an embodiment of the video zoom optical lens of the present invention.

[0038] The marks in the figure are respectively: 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. Specific Embodiments

[0039] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention.

[0040] It should be noted that like reference numerals and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it may not be further defined or explained in subsequent figures.

[0041] Embodiment 1:

[0042] As Figure 1 shown, a video zoom optical lens is composed of a transmissive group G1 with positive optical power, a transmissive group G2 with negative optical power, an aperture stop, a transmissive group G3 with positive optical power, a transmissive group G4 with positive optical power, a filter, and an image plane, which are sequentially arranged from the object side to the image side.

[0043] The transmissive group G1 is composed of a first lens, a second lens, and a third lens sequentially arranged in the direction from the object side to the image side, where 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 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.

[0044] The transmissive group G2 is composed of a fourth lens, a fifth lens, and a sixth lens sequentially arranged in the direction from the object side to the image side, where 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 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.

[0045] The transmissive group G3 is composed of a seventh lens, an eighth lens, and a ninth lens sequentially arranged in the direction from the object side to the image side, where 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 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.

[0046] The transmissive group G4 is composed of a tenth lens, an eleventh lens, and a twelfth lens sequentially arranged in the direction from the object side to the image side, where 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.

[0047] The transmission groups G2 and G4 are moving groups, and the transmission groups G1 and G3 are fixed groups. The focal length is changed by the movement of the transmission group G2 along the optical axis. Meanwhile, a position can be found through 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 imaging is clear.

[0048] 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 cementing in the present invention is only a combination means, and other similar reasonable means can be adopted.

[0049] The first to twelfth lenses are all spherical lenses. The lenses being spherical has a low manufacturing cost, can significantly reduce its selling price, is easily acceptable to consumers, and has good sales prospects.

[0050] At the short focal length position, the ratio range of the focal length of the transmission group G1 to the focal length of the entire optical system is (8.27, 8.62), the ratio range of the focal length of the transmission group G2 to the focal length of the entire optical system is (-1.78, -1.33), the ratio range of the focal length of the transmission group G3 to the focal length of the entire optical system is (3.26, 5.13), and the ratio range of the focal length of the transmission group G4 to the focal length of the entire optical system is (3.27, 4.59);

[0051] At the medium focal length position, the ratio range of the focal length of the transmission group G1 to the focal length of the entire optical system is (1.35, 2.01), the ratio range of the focal length of the transmission group G2 to the focal length of the entire optical system is (-0.66, -0.23), the ratio range of the focal length of the transmission group G3 to the focal length of the entire optical system is (0.61, 1.11), and the ratio range of the focal length of the transmission group G4 to the focal length of the entire optical system is (0.58, 1.16);

[0052] At the long focal length position, the ratio range of the focal length of the transmission group G1 to the focal length of the entire optical system is (0.69, 1.22), the ratio range of the focal length of the transmission group G2 to the focal length of the entire optical system is (-0.33, -0.09), the ratio range of the focal length of the transmission group G3 to the focal length of the entire optical system is (0.21, 0.56), and the ratio range of the focal length of the transmission group G4 to the focal length of the entire optical system is (0.39, 0.50).

[0053] Embodiment 2:

[0054] Based on Embodiment 1, a video zoom optical lens is proposed here. The ratio of the focal length of 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 lens group G1 to the focal length of the entire optical system at medium focus is 1.68, and the ratio of the focal length of lens group G1 to the focal length of the entire optical system at long focus is 0.84.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] The physical parameters of each lens meet the data requirements shown in Table 1:

[0059] Table 1 Physical parameters of each lens in this embodiment

[0060]

[0061] The optical system provided by a video zoom optical lens in this embodiment has the following optical technical indicators:

[0062] Working wavelength range: 435 nm - 656 nm;

[0063] Focal length f: 6 mm (W) - 60 mm (T);

[0064] Field of view: 69.3° (W) - 6.7° (T);

[0065] Maximum aperture: 28 mm;

[0066] Image plane size: 7 mm.

[0067] Note: W represents short focus, and T represents long focus.

[0068] Such as Figures 2 - 4As shown, the RayFan diagrams of the video zoom optical lens at short focus, medium focus, and long focus are respectively given. In the diagrams, the unit of the legend is μm, where ex represents the x-component of the ray aberration, ey represents the y-component of the ray aberration, px represents the x-coordinate of the entrance pupil, and py represents the y-coordinate of the entrance pupil. It can be seen that the meridional aberration and sagittal aberration within the entire focal length range of the video zoom optical lens are both small.

[0069] As Figures 5 - 7 shown, the SpotDiagram diagrams of the video zoom optical lens at short focus, medium focus, and long focus are respectively given. The unit of the legend in the diagrams is μm. It can be seen that the image spots within the entire spectral range and the entire field of view of the video zoom optical lens at short focus, medium focus, and long focus are all small.

[0070] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is 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 should not be construed as a limitation to the present invention.

[0071] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include direct contact between the first and second features, or may include the first and second features not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over", and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below", "beneath", and "underneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0072] The above are only the preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as a limitation to the present invention, and the protection scope of the present invention should be subject to the scope defined by the claims. For those of ordinary skill in the art in this technical field, without departing from the spirit and scope of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as within 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; 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).

2. 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.

3. 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.

4. 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.

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

Images