4k high definition, low distortion and deformation, video conference lens

Abstract

This invention discloses a 4K high-definition, low-distortion, and distortion-free video conferencing lens, belonging to the field of lens technology. It comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially along the optical axis from the object plane to the image plane. The first, fourth, and eighth lenses are all glass spherical lenses, while the second, third, fifth, sixth, and seventh lenses are all plastic aspherical lenses. The focal lengths of the eight lenses are negative, negative, negative, positive, positive, negative, positive, and positive, respectively. This invention's 4K high-definition, low-distortion, and distortion-free video conferencing lens achieves a resolution of over 8 million pixels, a horizontal field of view greater than 120°, and distortion within 10%, meeting the requirements for good video conferencing applications.

Description

Technical Field

[0001] This invention relates to the field of lens technology, specifically a 4K high-definition, low-distortion, non-deformation video conferencing lens. Background Technology

[0002] Video conferencing refers to meetings where people in two or more locations conduct face-to-face conversations via communication devices and networks. However, business video conferencing by government agencies, enterprises, and public institutions requires stable and secure networks, reliable meeting quality, and a formal meeting environment, necessitating the use of specialized video conferencing equipment and the establishment of dedicated video conferencing systems.

[0003] Video conferencing lenses are a crucial component of image information acquisition subsystems, and they themselves are constantly iterating and upgrading during their development. Wide field of view, high-definition images, low distortion, and no distortion have become increasingly sought-after features. For example, patent document CN 112415725 A discloses a low-distortion wide-angle lens for video conferencing, comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged along the optical axis from the object plane to the image plane, and an image plane. This invention reduces cost and lens weight by rationally using cemented lenses and limiting the optical power of each lens, and by employing two glass lenses and four plastic aspherical lenses. The lens of this invention has high and uniform MTF resolution, compatible with chips of eight megapixels or higher; it has low and positive distortion, resulting in better image capture when installed on camera equipment. Patent document CN 204241811 U discloses a large-aperture, high-pixel video conferencing lens, comprising a lens barrel, a plurality of lenses sequentially arranged within the lens barrel, and a chip protective glass. The plurality of lenses consist of a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged sequentially from the object side to the imaging side. An aperture is provided between the first and second lenses. The two ends of the first lens are fixed inside the lens barrel by lens caps, which are L-shaped. During installation, one end of the lens cap is clamped to the lens barrel wall, and the other end is clamped to the object surface of the first lens at both ends. A sealing ring is provided between the two ends of the first lens and the lens barrel. A spacer is provided between the third and fourth lenses and separated by the spacer. This utility model has a simple structure, is easy to use, has strong versatility, and high pixel count. However, neither of the video conferencing lenses disclosed in the above two patent documents can meet the requirements for a large field of view, high definition, low distortion, and no deformation. Summary of the Invention

[0004] In view of this, the present invention addresses the shortcomings of the prior art by providing a 4K high-definition optical lens with a horizontal field of view greater than 120°, low distortion, no image distortion.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a 4K high-definition, low-distortion, and deformation-free video conferencing lens, comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially along the optical axis from the object plane to the image plane; the first lens, the fourth lens, and the eighth lens are all glass spherical lenses, and the second lens, the third lens, the fifth lens, the sixth lens, and the seventh lens are all plastic aspherical lenses; the focal lengths of the eight lenses are negative, negative, negative, positive, positive, negative, positive, and positive, respectively.

[0006] Furthermore, the mirror parameters of the first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, and eighth lens are as follows:

[0007]

[0008]

[0009] Furthermore, the aspherical coefficients of the second, third, fifth, sixth, and seventh lenses are:

[0010] Face number a2 a3 a4 a5 a6 a7 4 3.88E-03 -1.12E-04 2.56E-07 3.78E-08 -4.18E-10 5 3.72E-03 4.31E-04 -4.92E-05 2.35E-08 9.94E-08 -2.00E-09 6 1.68E-04 -1.12E-07 3.67E-06 -1.88E-08 -1.07E-08 -5.01E-11 7 1.59E-03 -8.40E-05 4.76E-05 3.37E-06 -8.75E-07 3.74E-08 11 -3.16E-04 -6.36E-03 5.97E-03 -2.03E-03 -1.71E-03 1.20E-03 12 5.18E-04 -1.30E-02 1.40E-02 1.30E-03 -6.99E-03 2.40E-03 13 -3.99E-02 1.69E-02 4.12E-03 -1.88E-03 -3.70E-03 1.96E-03 14 7.25E-03 7.21E-03 -1.95E-03 -8.48E-04 3.84E-04 -3.83E-05 15 -1.61E-03 6.62E-03 -2.23E-05 -9.74E-04 2.82E-04 -3.00E-05 16 -1.04E-02 5.03E-03 -1.02E-03 5.37E-05 5.79E-05 -1.03E-05

[0011] a2, a3, a4, a5, a6, and a7 are the aspheric coefficients of the 4th, 6th, 8th, 10th, 12th, and 14th degree terms of even-order aspheric surfaces.

[0012] Furthermore, 4K high-definition, low-distortion, and distortion-free video conferencing lenses have a horizontal field of view greater than 120° and distortion within 10%.

[0013] Furthermore, the resolution of 4K high-definition, low-distortion, and non-deformation video conferencing lenses reaches over 8 million pixels.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. This invention simplifies costs through a 3G5P glass-plastic hybrid structure; at the same time, by selecting the materials of each lens and correcting the shape and coefficient of the aspherical surface, it not only expands the horizontal field of view but also achieves high pixel count, with a resolution of over 8 million pixels.

[0016] 2. This invention utilizes multiple plastic aspherical lenses. By selecting the material of the first lens (i.e., a glass spherical lens) and correcting the shape and coefficient of the second and third plastic aspherical lenses, distortion is reduced to within 10%. At the same time, the magnification remains consistent across different positions of the image. This optimization of distortion and magnification achieves both distortion-free and constant magnification effects.

[0017] 3. This invention achieves passive heatless operation by allocating optical power to each lens and selecting lens materials. Appropriate metal spacers and SOMA sheets are matched according to the shape of each lens to ensure structural stability. This invention achieves defocus-free operation in high and low temperature environments (high temperature +80℃, low temperature -40℃), vibration, and thermal shock through precise coordination of structure and optics. Attached Figure Description

[0018] Figure 1 This is a structural schematic diagram of an embodiment of the present invention;

[0019] Figure 2 This is a curve showing the spherical aberration and axial chromatic aberration of the 4K high-definition, low-distortion, deformation-free, and video conferencing lens of this invention.

[0020] Figure 3 This is a curve of the image scattering of the 4K high-definition, low-distortion, non-deformation, video conferencing lens of this invention.

[0021] Figure 4 This is the lateral chromatic aberration diagram of the 4K high-definition, low-distortion, deformation-free video conferencing lens of this invention;

[0022] Figure 5 This is the MTF curve of the 4K high-definition, low-distortion, deformation-free video conferencing lens of this invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0024] Example 1

[0025] like Figure 1 As shown, a 4K high-definition, low-distortion, and deformation-free video conferencing lens includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, and an eighth lens 8 arranged sequentially along the optical axis from the object plane to the image plane; the first lens 1, the fourth lens 4, and the eighth lens 8 are all glass spherical lenses, while the second lens 2, the third lens 3, the fifth lens 5, the sixth lens 6, and the seventh lens 7 are all plastic aspherical lenses; the focal lengths of the eight lenses are negative, negative, negative, positive, positive, negative, positive, and positive, respectively.

[0026] The mirror parameters of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7, and the eighth lens 8 are as follows:

[0027]

[0028] EVENASPH: Even-order aspherical surface

[0029] STANDARD: Standard surface (spherical surface).

[0030] The aspherical coefficients of the second lens 2, the third lens 3, the fifth lens 5, the sixth lens 6, and the seventh lens 7 are:

[0031] Face number a2 a3 a4 a5 a6 a7 4 3.88E-03 -1.12E-04 2.56E-07 3.78E-08 -4.18E-10 5 3.72E-03 4.31E-04 -4.92E-05 2.35E-08 9.94E-08 -2.00E-09 6 1.68E-04 -1.12E-07 3.67E-06 -1.88E-08 -1.07E-08 -5.01E-11 7 1.59E-03 -8.40E-05 4.76E-05 3.37E-06 -8.75E-07 3.74E-08 11 -3.16E-04 -6.36E-03 5.97E-03 -2.03E-03 -1.71E-03 1.20E-03 12 5.18E-04 -1.30E-02 1.40E-02 1.30E-03 -6.99E-03 2.40E-03 13 -3.99E-02 1.69E-02 4.12E-03 -1.88E-03 -3.70E-03 1.96E-03 14 7.25E-03 7.21E-03 -1.95E-03 -8.48E-04 3.84E-04 -3.83E-05 15 -1.61E-03 6.62E-03 -2.23E-05 -9.74E-04 2.82E-04 -3.00E-05 16 -1.04E-02 5.03E-03 -1.02E-03 5.37E-05 5.79E-05 -1.03E-05

[0032] a2, a3, a4, a5, a6, and a7 are the aspheric coefficients of the 4th, 6th, 8th, 10th, 12th, and 14th degree terms of even-order aspheric surfaces.

[0033] Figure 2 This is a curve of spherical aberration and axial chromatic aberration of the optical system of this invention. The main parts are corrected to within ±0.02mm. The spherical aberration is well corrected within the spectral bandwidth, achieving a balance between the inner and outer apertures, which can increase the cleanliness of the actual image captured by the lens.

[0034] Figure 3 This is a graph of the astigmatism and field curvature of the optical system of the present invention. Due to the use of multiple plastic aspherical lenses, astigmatism and field curvature can be corrected to a suitable range, so that the resolving power in the meridional direction can be close to the resolving power in the sagittal direction.

[0035] Figure 4 This is the chromatic aberration diagram of the optical system of this invention. The chromatic aberration of f, d, and c rays relative to the chromatic aberration of ...

[0036] Figure 5 This is the MTF curve of the optical system of the present invention. As can be seen from the MTF curve, the lens has excellent resolution and high sharpness at a spatial frequency of 160 cycles / mm within the center field of view and the 0.9 field of view.

[0037] Expanding the horizontal field of view presents challenges in correcting distortion and magnification. Furthermore, this invention requires ensuring that the first lens is a glass spherical lens. By selecting the material for the first lens and modifying the shape and coefficients of the second and third plastic aspherical lenses, a horizontal field of view greater than 120° is achieved, with distortion within 10%, while maintaining consistent magnification across different positions on the image.

[0038] When correcting distortion and magnification parameters using the first lens 1, second lens 2, third lens 3, and fourth lens 4, other aberrations are introduced as little as possible. Through the allocation of optical power and aberration correction using the fifth lens 5, sixth lens 6, seventh lens 7, and eighth lens 8, the final resolution reaches over 8 million pixels.

[0039] Example 2

[0040] The 4K high-definition, low-distortion, non-deformation, video conferencing lens of this embodiment differs from that of Embodiment 1 in that: a plastic lens barrel 9 for fixing optical elements and adjusting optical lenses is provided on the outside of the first lens 1, second lens 2, third lens 3, fourth lens 4, fifth lens 5, sixth lens 6, seventh lens 7, and eighth lens 8; a first metal spacer 10 is provided between the third lens 3 and the fourth lens 4; a second metal spacer 11 is provided between the fourth lens 4 and the fifth lens 5; a third metal spacer 12 is provided between the seventh lens 7 and the eighth lens 8; and an SOMA sheet is provided between the fifth lens 5 and the sixth lens 6. The metal spacers and SOMA sheets play a role in sinking and blocking light in the overall structure of the lens.

[0041] In this embodiment of the invention, since one of the difficulties of glass-plastic hybrid lenses is stability and reliability, the present invention adopts passive calorimetry to achieve non-defocusing operation in high and low temperature environments (high temperature +80℃, low temperature -40℃). Passive calorimetry is achieved by distributing the optical power of the lens and selecting the lens material.

[0042] This invention ensures that there is no blurring due to vibration and thermal shock by using component fitting process and planar support. Appropriate gaskets and SOMA sheets are matched according to the shape of each lens to ensure structural stability, thereby resisting the damage to the lens caused by vibration and thermal shock.

[0043] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A 4K high-definition, low-distortion, non-deformation video conferencing lens, characterized in that: The system includes a first lens (1), a second lens (2), a third lens (3), a fourth lens (4), a fifth lens (5), a sixth lens (6), a seventh lens (7), and an eighth lens (8) arranged sequentially along the optical axis from the object plane to the image plane; the first lens (1), the fourth lens (4), and the eighth lens (8) are all glass spherical lenses, while the second lens (2), the third lens (3), the fifth lens (5), the sixth lens (6), and the seventh lens (7) are all plastic aspherical lenses; the optical power of the eight lenses is negative, negative, negative, positive, positive, positive, negative, positive, positive, positive in sequence; The mirror parameters of the first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5), the sixth lens (6), the seventh lens (7), and the eighth lens (8) are as follows: The aspherical coefficients of the second lens (2), the third lens (3), the fifth lens (5), the sixth lens (6), and the seventh lens (7) are: a2, a3, a4, a5, a6, and a7 are the aspheric coefficients of the 4th, 6th, 8th, 10th, 12th, and 14th degree terms of even-degree aspheric surfaces; 4K high-definition, low-distortion, distortion-free video conferencing lenses with a horizontal field of view greater than 120° and distortion within 10%; The 4K high-definition, low-distortion, and distortion-free video conferencing lens has a resolution of over 8 million pixels.

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