Optical imaging module and mobile electronic equipment

Abstract

The invention relates to the technical field of optical imaging, and particularly provides an optical imaging module and mobile electronic equipment. The optical imaging module comprises a first imaging lens; the first imaging lens is configured to form a first visual image according to light in a first view field range; a second imaging lens; the second imaging lens is configured to form a second visual image according to light in a second view field range; wherein the target surface of the second imaging lens is smaller than that of the first imaging lens; the second view field range comprises the first view field range; and the processor is configured to perform distortion correction on the first visual image according to the second visual image so as to obtain a target image. According to the technical scheme provided by the invention, the thickness of the optical imaging module can be reduced to a certain extent, and meanwhile, the imaging quality is improved.

Description

Technical Field

[0001] This invention relates to the field of optical imaging technology, and in particular to an optical imaging module and a portable electronic device. Background Technology

[0002] With the rapid development of mobile electronic devices, such as smartphones, people are increasingly inclined to use the optical imaging modules on these devices to take photos and record their lives due to their portability. As a result, the current iteration and upgrading of these devices largely reflects the improvement of the imaging performance of the optical imaging modules.

[0003] To improve the imaging performance of optical imaging modules and pursue higher image quality, the use of large-area image sensors has become an effective approach in the smartphone industry. Larger image sensors have larger individual pixels, meaning a higher signal-to-noise ratio, which significantly improves image quality. However, larger image sensors inevitably lead to a larger overall length and volume of the optical imaging module. When mounted on a smartphone, this results in the optical imaging module protruding significantly from the smartphone body, reducing the overall aesthetic appeal of the product. Summary of the Invention

[0004] The optical imaging module and portable electronic device provided by the present invention improve the imaging quality of the optical imaging module while reducing the thickness of the optical imaging module.

[0005] In a first aspect, the present invention provides an optical imaging module, comprising: a first imaging lens; the first imaging lens being configured to form a first visual image based on light within a first field of view; a second imaging lens; the second imaging lens being configured to form a second visual image based on light within a second field of view; wherein the target surface size of the second imaging lens is smaller than the target surface size of the first imaging lens; the second field of view includes the first field of view; and a processor configured to perform distortion correction on the first visual image based on the second visual image to obtain a target image.

[0006] In one embodiment of the present invention, the second imaging lens includes a filter; the filter is used to project light within a preset wavelength range onto the image plane of the second imaging lens.

[0007] In one embodiment of the present invention, the second visual image is a grayscale image.

[0008] In one embodiment of the present invention, the second imaging lens includes a lens group; the lens group includes multiple lenses; each of the multiple lenses includes an objective lens and an image lens; light within the second field of view passes sequentially through the objective lens and the image lens of each lens and is then projected onto the image plane of the second imaging lens; wherein the multiple lenses are coaxially arranged.

[0009] In one embodiment of the present invention, the objective lens surface has at least one of the following surface types: spherical, aspherical, or freeform optical surface; and / or, the image mirror surface has at least one of the following surface types: spherical, aspherical, or freeform optical surface.

[0010] In one embodiment of the present invention, the lens group has 3 to 7 lenses, and the thickness of the lens group is less than or equal to 6 mm.

[0011] In one embodiment of the present invention, the half field of view of the second imaging lens is greater than or equal to 61°.

[0012] In one embodiment of the present invention, the total length of the first imaging lens is TTL_D, the image height is IMH_D, the field of view is FIE_D, and the aperture value is FNO_D; wherein, TTL_D / 2*IMH_D<0.6, IMH_D≥5.16 mm, and TTL_D≤5.8 mm.

[0013] In one embodiment of the present invention, the total length of the second imaging lens is TTL_X, the image height is IMH_X, the field of view is FIE_X, the absolute value of the maximum optical distortion is DIS_X, and the aperture value is FNO_X; wherein, TTL_X≤TTL_D, FIE_X≥FIE_D, DIS_X≤0.5%, IMH_X <IMH_D,IMH_X≥2.2mm,FNO_X≤FNO_D。

[0014] In one embodiment of the present invention, the distance between the second imaging lens and the first imaging lens is less than or equal to a preset threshold.

[0015] In a second aspect, the present invention provides a portable electronic device, the portable electronic device comprising the optical imaging module described in any of the preceding claims.

[0016] This invention provides an optical imaging module comprising a first imaging lens, a second imaging lens, and a processor. The target surface size of the first imaging lens is larger than that of the second imaging lens, resulting in higher imaging quality for the first visual image captured by the first imaging lens. However, the larger target surface size of the first imaging lens also means its overall length (thickness) is greater than that of the second imaging lens; in other words, the thickness of the first imaging lens determines the overall thickness of the optical imaging module. To reduce the overall thickness of the optical imaging module, the overall length (thickness) of the first imaging lens is compressed, resulting in greater distortion in the image captured by the first imaging lens. The smaller target surface size of the second imaging lens allows for a smaller overall length (thickness), thus ensuring that the thickness of the second imaging lens is no greater than that of the first imaging lens, while also confining the distortion of the second visual image within a smaller range. The processor then performs distortion correction on the first visual image based on the second visual image to obtain a target image. The target image possesses the high imaging quality characteristics resulting from the large target surface of the first imaging lens and the low distortion characteristics resulting from the small distortion of the second imaging lens. Therefore, the imaging quality of the optical imaging module can be improved to a certain extent while reducing the overall thickness of the optical imaging module. Attached Figure Description

[0017] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other embodiments based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of the structure of an optical imaging module provided in an embodiment of the present invention.

[0019] Figure 2 A schematic diagram of the structure of an image correction method provided in an embodiment of the present invention.

[0020] Figure 3 A schematic diagram of the structure of the second imaging lens provided in the first embodiment of the present invention.

[0021] Figure 4 This is a diagram showing the distortion parameters of the second imaging lens in the first embodiment.

[0022] Figure 5 A schematic diagram of the structure of the second imaging lens provided for the second embodiment of the present invention.

[0023] Figure 6 This is a diagram showing the distortion parameters of the second imaging lens in the second embodiment.

[0024] Figure 7-a A schematic diagram of a large-target-area, large-distortion imaging lens in the third embodiment of the present invention.

[0025] Figure 7-b This is a schematic diagram of a small-target-area, small-distortion imaging lens in the third embodiment.

[0026] Figure 8-a This is a graph showing the distortion rate of a large-target-area, large-distortion imaging lens as a function of the object-side field of view in the third embodiment.

[0027] Figure 8-b The image shows the transverse chromatic aberration of light with wavelengths of 650nm, 610nm, 555nm, 510nm, 470nm, and 435nm after passing through a large-target, highly distorted imaging lens in the third embodiment.

[0028] Figure 8-c This is an axial spherical aberration diagram of light with a wavelength of 555nm after passing through a large-target-area, highly distorted imaging lens in the third embodiment.

[0029] Figure 9-a This is a graph showing the distortion rate of a small-target-area, small-distortion imaging lens in the third embodiment as a function of the object-side field of view.

[0030] Figure 9-b The image shows the transverse chromatic aberration of light with wavelengths of 650nm, 610nm, 555nm, 510nm, 470nm, and 435nm after passing through a small-target-area, low-distortion imaging lens in the third embodiment.

[0031] Figure 9-c This is an axial spherical aberration diagram of light with a wavelength of 555nm after passing through a small-target-area, low-distortion imaging lens in the third embodiment.

[0032] Figure 10-a This is a schematic diagram of a large-target-area, large-distortion imaging lens in the fourth embodiment.

[0033] Figure 10-b This is a schematic diagram of a small-target-area, low-distortion imaging lens in the fourth embodiment.

[0034] Figure 11-a This is a graph showing the variation of distortion rate with object-side field of view for a small-target-area, small-distortion imaging lens in the fourth embodiment.

[0035] Figure 11-b The image shows the transverse chromatic aberration of light with wavelengths of 650nm, 610nm, 555nm, 510nm, 470nm, and 435nm after passing through a small-target-area, low-distortion imaging lens in the fourth embodiment.

[0036] Figure 11-c This is an axial spherical aberration diagram of light with a wavelength of 555nm after passing through a small-target-area, low-distortion imaging lens in the fourth embodiment.

[0037] Figure 12-a This is a schematic diagram of a large-target-area, large-distortion imaging lens in the fifth embodiment.

[0038] Figure 12-b This is a schematic diagram of a small-target-area, low-distortion imaging lens in the fifth embodiment.

[0039] Figure 13-a This is a graph showing the distortion rate of a small-target-area, small-distortion imaging lens as a function of the object-side field of view in the fifth embodiment.

[0040] Figure 13-b The image shows the transverse chromatic aberration of light with wavelengths of 650nm, 610nm, 555nm, 510nm, 470nm, and 435nm after passing through a small-target, low-distortion imaging lens in the fifth embodiment.

[0041] Figure 13-c This is an axial spherical aberration diagram of light with a wavelength of 555nm after passing through a small-target-area, low-distortion imaging lens in the fifth embodiment.

[0042] Figure 14 A schematic diagram illustrating image correction provided for the present invention.

[0043] Explanation of reference numerals in the attached figures

[0044] 100. Optical imaging module; 110. First imaging lens; 120. Second imaging lens; 121. Filter; 122. Lens group; aa. First direction. Detailed Implementation

[0045] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0046] Distortion is one of the various types of aberrations in optical lens imaging. It occurs because the magnification of the image changes with the field of view, causing the image to lose its resemblance to the object. This image distortion is called distortion. According to optical aberration theory, one characteristic of distortion is that it does not affect the sharpness of the image. By utilizing this characteristic, distortion constraints can be relaxed during lens design, allowing for a reduction in the overall length (thickness) of the lens while maintaining image quality or sharpness. The main trade-off is that the distortion of the image will increase.

[0047] Researchers have discovered that existing cameras in portable electronic products such as smartphones exhibit significant geometric distortion during image capture. This is primarily due to the limitations of smartphones' thin and light designs, resulting in small image sensors and a close proximity to the lens. Consequently, edge light rays are projected onto the sensor with a higher degree of offset, leading to image distortion.

[0048] In related technologies, there are two main technical approaches to image distortion correction. The first is based on correction algorithms using traditional optical models and camera parameters. This involves pre-calibrating the lens's intrinsic and distortion parameters, then calculating a reverse mapping to correct the image. However, this method heavily relies on the accuracy of the calibration parameters, and in practical applications, factors such as lens tolerances and environmental temperature variations can hinder achieving ideal results. Furthermore, this method struggles to effectively handle near-object distortion caused by perspective effects. The second approach is based on deep learning-based intelligent correction algorithms. These algorithms are trained using a large amount of data from distorted image correction to achieve the goal of correcting image distortion. However, this method is costly and lacks general optimization capabilities across different lenses. Additionally, this method puts pressure on the processing power of mobile devices; insufficient computing power can cause inter-frame jitter or lag in the video.

[0049] The methods described above primarily acquire information through a single sensor and rely on algorithms to estimate and compensate for distortion. Both approaches lack an objective, accurate physical reference that does not require logical reasoning or complex training to guide the distortion correction process.

[0050] Based on this, the present invention proposes an optical imaging module comprising a first imaging lens, a second imaging lens, and a processor. The target surface size of the first imaging lens is larger than that of the second imaging lens, resulting in higher imaging quality of the first visual image formed by the first imaging lens. However, the larger target surface size of the first imaging lens also means its total length (i.e., thickness) is greater than that of the second imaging lens; in other words, the thickness of the first imaging lens determines the thickness of the entire optical imaging module. To reduce the overall thickness of the optical imaging module, the total length (i.e., thickness) of the first imaging lens is compressed, resulting in greater distortion in the image formed by the first imaging lens. The smaller target surface size of the second imaging lens allows for a smaller total length (i.e., thickness), thus ensuring that the thickness of the second imaging lens is no greater than that of the first imaging lens, while also confining the distortion of the second visual image within a smaller range. Then, the processor performs distortion correction on the first visual image based on the second visual image to obtain a target image. The target image possesses the high imaging quality characteristics brought by the large target surface of the first imaging lens and the small distortion characteristics brought by the small distortion of the second imaging lens. Therefore, the imaging quality of the optical imaging module can be improved to a certain extent while reducing the overall thickness of the optical imaging module.

[0051] Please see Figure 1 , Figure 2 and Figure 4 The present invention provides an optical imaging module 100. The optical imaging module 100 includes a first imaging lens 110, a second imaging lens 120, and a processor.

[0052] A first imaging lens 110 is configured to form a first visual image based on light within a first field of view. A second imaging lens 120 is configured to form a second visual image based on light within a second field of view. The target surface size of the second imaging lens 120 is smaller than that of the first imaging lens 110, and the second field of view includes the first field of view.

[0053] The processor is configured to perform distortion correction on the first visual image based on the second visual image to obtain the target image.

[0054] In this embodiment, the first imaging lens 110 can be used to acquire light within a first field of view, and then form a first visual image based on the light within the first field of view. The first field of view determines the range of the scene that the lens can capture, and its size and angle affect the final imaging field of view. In actual shooting, when a user uses a device equipped with the optical imaging module 100 to take a picture, the first imaging lens 110 will collect and focus the light within its corresponding first field of view, converting this light into a first visual image. This first visual image contains rich scene information, but may have distortion problems due to the large field of view.

[0055] In some alternative embodiments, the first imaging lens 110 is a wide-angle lens or an ultra-wide-angle lens with a half-field of view of approximately 60°. It is understood that in other embodiments, the first imaging lens 110 may also be the main camera lens of a smart device.

[0056] In this embodiment, the second imaging lens 120 can be used to acquire light within a second field of view, and then form a second visual image based on the light within the second field of view. In practical applications, because the target surface size of the second imaging lens 120 is small, when the distortion of its imaging is limited to a very small range, the total length, i.e., the thickness, of the second imaging lens 120 can still be controlled to be less than the thickness of the first imaging lens 110. Furthermore, the second field of view includes the first field of view, which allows the second imaging lens 120 to acquire image information from a wider viewing angle, providing more data support for subsequent distortion correction.

[0057] In this embodiment, effective correction of image distortion is achieved through a unique dual-lens design, namely the first imaging lens 110 and the second imaging lens 120, and the collaborative work of the processor. The first imaging lens 110 is responsible for acquiring light within a first field of view and forming a first visual image. This image typically contains rich scene information, but suffers from significant distortion due to the compression of the lens's overall length and thickness. The second imaging lens 120 forms a second visual image based on light within a second field of view. Its target surface size is smaller than that of the first imaging lens 110, and the second field of view includes the first field of view. This design allows the second imaging lens 120 to acquire image information from a wider field of view, providing more data support for subsequent distortion correction. The processor, as the core of the entire system, performs distortion correction on the first visual image based on the second visual image to obtain the target image. In this way, the advantages of both lenses are fully utilized, compensating for the shortcomings of a single lens, reducing the degree of image distortion at large angles, and effectively improving image quality.

[0058] Please see Figure 2 In this embodiment, the method by which the processor 130 performs distortion correction on an image may include the following steps.

[0059] Step S110: Acquire a first visual image and a second visual image; wherein, the first visual image is formed by the first imaging lens 110 based on light within a first field of view, and the second visual image is formed by the second imaging lens 120 based on light within a second field of view; the second field of view includes the first field of view.

[0060] Step S120: Input the first visual image into the image generation network to obtain a corrected image; the image generation network is used to correct the distortion of the first visual image.

[0061] Step S130: Input the corrected image and the second visual image into the image discrimination network to obtain the first loss data of the corrected image and the second visual image.

[0062] Step S140: When the first loss data is greater than the first preset loss, update the parameters of the image generation network according to the first loss data, regenerate the corresponding corrected image according to the first visual image, until the first loss data is less than or equal to the first preset loss, and determine the current corrected image as the target corrected image.

[0063] In this embodiment, a first visual image is displayed on the image sensor of the first imaging lens. A second visual image is displayed on the image sensor of the second imaging lens. When taking a picture using a portable electronic device, the first imaging lens can be activated to capture light within a first field of view. Simultaneously, the second imaging lens is also activated to capture light within a second field of view.

[0064] In this embodiment, the image generation network takes a first visual image as input and generates synthetic data, i.e., a corrected image, through a series of fully connected layers, convolutional layers, and activation functions. The image generation network refers to the generator part of a generative adversarial network (GAN). The GAN generates a corrected image, which is then used by a discriminator to determine whether it conforms to the real data.

[0065] In this embodiment, the image discrimination network refers to the discriminator part in a generative adversarial network (GAN). The image discrimination network is used to determine the difference between the corrected image generated by the image generation network and the second visual image.

[0066] In this embodiment, the feedback information provided by the discriminator in a GAN is quite limited. When the original data is very complex and the discriminator cannot convey more detailed information, the generator naturally cannot generate convincing "fake data." To alleviate this problem and further improve the performance of the generative adversarial network (GAN) model, we can provide the generator or discriminator with second visual data to assist the model's adversarial performance. By calculating various feature differences in the image, we output first loss data to measure the similarity between the corrected image and the second visual image, providing a basis for subsequent optimization of the corrected image.

[0067] In this embodiment, the first loss data is the data obtained after inputting the corrected image and the second visual image into the image discrimination network. It quantifies the difference between the corrected image and the second visual image. The first loss data includes the sum of the losses of the image generation network and the image discrimination network. This data reflects the degree of inconsistency between the current corrected image after correction by the image generation network and the reference second visual image in terms of content, features, etc. The smaller the value, the more similar the two are, and the better the correction effect.

[0068] In this embodiment, through iterative optimization of the generation and discrimination networks until the first loss data meets preset conditions, the correction effect can be continuously optimized, ensuring that the final target corrected image has high correction accuracy. The image is determined when the total loss data of the corrected image is less than or equal to the first preset loss after repeated image generation and discrimination steps. At this point, after multiple rounds of optimization, the difference between this image and the reference image is small enough to meet the preset standard, its distortion is effectively corrected, and the imaging quality reaches the desired level, making it a high-quality final output image for user use.

[0069] In this embodiment, the parameters of the image generation network can be a random noise vector. This random noise vector is randomly generated based on the first visual image.

[0070] In some implementations, inputting the corrected image and the second visual image into an image discrimination network to obtain first loss data for the corrected image and the second visual image may include: segmenting the second visual image to obtain a second feature image; wherein the field of view corresponding to the second feature image is the same as the field of view of the first feature image; and inputting the corrected image and the second feature image into an image discrimination network to obtain first loss data for the corrected image and the second feature image.

[0071] In this embodiment, segmenting the second visual image to obtain the second feature image refers to cropping the portion of the larger mosaic image (the second visual image) that has the same field of view as the first visual image. This ensures that the field of view of the second feature image is identical to that of the first visual image, facilitating accurate comparison with the corrected image later. Specifically, for example, if the second visual image has a long side pixel count of 0-679 and a short side pixel count of 0-539, and the long side pixel count (13-659) and short side pixel count (13-529) are identical to the first visual image, then this portion is cropped out as the second feature image.

[0072] In some implementations, inputting the corrected image and the second feature image into an image discrimination network to obtain first loss data for the corrected image and the second feature image may include: performing downsampling processing on the corrected image to obtain a first feature image; wherein the first feature image and the second feature image have the same resolution; and inputting the first feature image into an image discrimination network to obtain first loss data for the first feature image and the second feature image.

[0073] In this embodiment, downsampling is like reducing a high-resolution image by a certain ratio, making the first feature image and the second feature image have the same resolution. This consistency in resolution between the two feature images facilitates accurate analysis and comparison by the image discrimination network. These image segmentation and feature extraction operations lay the foundation for subsequent accurate calculation of loss data and optimization of the correction image. Specifically, for example, in the above embodiment, if the resolution of the segmented second feature image is 650*520, then the resolution of the downsampled first feature image will also be 650*520.

[0074] In some embodiments, the image correction method may further include: comparing the similarity between the first feature image and the second feature image to obtain second loss data between the first feature image and the second feature image; the second loss data is used to represent the dissimilarity between the first feature image and the second feature image; adding the first loss data and the second loss data to obtain total loss data; correspondingly, the step of determining the current corrected image as the target image may include: repeating the above image generation step and image discrimination step until the total loss data is less than or equal to a second preset loss, and then determining the current corrected image as the target corrected image.

[0075] Please continue reading. Figure 2 In this embodiment, the first loss data is obtained by inputting the first feature image and the second feature image into the image discrimination network. It reflects the degree of difference between the corrected image and the processed second visual image (second feature image). At the same time, the first feature image and the second feature image are compared for similarity to obtain the second loss data. This second loss data is used to represent the dissimilarity between the first feature image and the second feature image, that is, the difference between the two.

[0076] Then, the first and second loss data are added together to obtain the total loss data. The total loss data comprehensively reflects the differences between the corrected image and the reference image (the second feature image) in various aspects. When determining the target corrected image, the image generation and image discrimination steps are repeated to continuously optimize the corrected image. Only when the total loss data is less than or equal to the second preset loss is the current corrected image determined as the target corrected image. This means that after multiple rounds of optimization, the difference between the corrected image and the reference image has become small enough to meet our preset standard, achieving the ideal correction effect.

[0077] By acquiring a first visual image and a second visual image, an image generation network is used to correct distortion in the first visual image. Then, an image discriminant network is used to analyze the differences between the corrected image and the second visual image, forming a complete and closed-loop correction optimization system. This approach can more accurately identify and correct distortions in images, significantly improving the accuracy and effectiveness of image correction compared to traditional methods.

[0078] In terms of cost reduction, this method avoids the high cost of training with large amounts of data in traditional deep learning-based correction algorithms. It cleverly utilizes the characteristics of different imaging lenses through a unique dual-image input and dual-network collaboration approach, reducing reliance on large-scale data training and thus lowering computational resource and time costs.

[0079] In terms of enhancing generalization ability, since this method does not rely entirely on training with a large amount of data for a specific lens, but is based on the comparison and processing of images with different fields of view, it has stronger adaptability to different lenses and scenes, and its generalization ability is significantly improved. By using a nearly distortion-free second visual image formed by the second imaging lens 120 to correct distortion in the first visual image, compared to directly correcting distortion in the first visual image using only deep learning algorithms, this method reduces the computing power required by the processor, improves the processor's efficiency in correcting distortion in the first visual image, and compensates for the real-time shortcomings of traditional distortion correction algorithms, thereby improving the user experience when using the optical imaging module 100 for shooting. Furthermore, the existence of a nearly distortion-free second visual image ensures better protection of the distortion correction effect on the first visual image.

[0080] Furthermore, since the first imaging lens 110 is the thickest part of the optical imaging module 100, in order to make the optical imaging module 100 thinner, the first imaging lens 110 needs to be designed to be thinner, thereby freeing up some distortion of the first imaging lens 110. Then, the distortion of the first visual image is corrected by the second visual image, so that even with a thinner overall optical imaging module 100, the target image it forms also has the characteristics of high resolution, wide field of view, and ultra-small distortion.

[0081] In some embodiments, the second imaging lens 120 includes a filter 121; the filter 121 is used to project light within a preset wavelength range onto the image plane of the second imaging lens 120.

[0082] In this embodiment, in some shooting scenarios, only light of a specific wavelength may be needed to participate in imaging. The filter 121 can block other unwanted light, making the light projected onto the image surface purer, thereby providing a more reliable data foundation for the processor and further optimizing the distortion correction effect of the image.

[0083] In this embodiment, the filter 121 differs from the filter 121 in a conventional optical imaging module 100. While the conventional optical imaging module 100 images light in the visible light band (approximately 390nm-770nm), the filter 121 in this invention is designed to allow only a narrower wavelength band (e.g., around 850nm) of light to pass through. This wavelength band effectively avoids most ambient light interference, and the image sensor also has good sensitivity to this wavelength band, which is beneficial for image quality.

[0084] In this embodiment, please refer to Figure 2 and Figure 3 The filter 121 is located between the lens group 122 and the imaging surface of the imaging sensor. It is understood that in some other embodiments, the filter 121 may also be located between the object and the lens group 122, or between any two lenses in the lens group 122.

[0085] In some implementations, the second visual image is a grayscale image.

[0086] In this embodiment, the second visual image is a grayscale image. This reduces the bandwidth requirements for data transmission and the computational burden on the processor during image transmission and processing, thereby improving processing efficiency. Simultaneously, grayscale images possess unique advantages in edge detection and image recognition, facilitating image analysis and processing by the processor. When performing distortion correction on the first visual image, these characteristics of grayscale images help the processor more quickly and accurately identify key information in the image, thus more effectively correcting distortion and improving the quality of the target image.

[0087] In some embodiments, the second imaging lens 120 includes a lens group 122; the lens group 122 includes a plurality of lenses; each of the plurality of lenses includes an objective lens and an image lens; light within the second field of view passes sequentially through the objective lens and the image lens of each lens and is then projected onto the image plane of the second imaging lens 120; wherein the plurality of lenses are coaxially arranged.

[0088] In this embodiment, the second imaging lens 120 includes a lens group 122 composed of multiple coaxially arranged lens groups 122. Light passes sequentially through the objective lens and image lens of each lens before being projected onto the image plane. This structural design ensures the stability and accuracy of light propagation, enabling the second imaging lens 120 to accurately capture light and form a clear image. The coordinated operation of multiple lenses allows for multiple refractions and focusing of light, thereby better correcting aberrations and improving image quality.

[0089] In this embodiment, the lens group 122 included in the second imaging lens 120 consists of multiple lens groups 122. These lenses cooperate with each other during operation to jointly complete the task of refracting and focusing light. All the lenses are coaxially arranged, which ensures that light always propagates along the same optical axis when passing through each lens, thereby ensuring the accuracy and stability of the image. For example, when light enters the lens group 122 from the object side, it passes through the objective and image surfaces of each lens in sequence. During this process, each lens affects the direction of light propagation and the degree of focusing, ultimately ensuring that the light is accurately presented on the image plane of the second imaging lens 120.

[0090] In some embodiments, the objective lens surface has at least one of the following shapes: spherical, aspherical, or freeform optical surface; and / or, the image mirror surface has at least one of the following shapes: spherical, aspherical, or freeform optical surface.

[0091] In this embodiment, the surface shapes of the objective lens and image mirror have a significant impact on the optical performance of the lens. The objective lens surface shape includes at least one of the following: spherical, aspherical, or freeform optical surface, and the same applies to the image mirror. A spherical surface is a common type, possessing a simple geometry and being relatively easy to manufacture. Aspherical surfaces can better correct aberrations and improve image quality, especially excelling in optical systems with large field of view and large aperture. Freeform optical surfaces have more complex shapes and can be customized to meet specific optical requirements, further optimizing the performance of the optical system. Different surface shapes can be selected and combined according to the actual application scenario and image quality requirements to achieve the best optical effect.

[0092] Specifically, for example, lens group 122 includes three lenses: lens 1, lens 2, and lens 3. Among them, the objective lens of lens 1 has an aspherical surface and the image lens has a freeform optical surface; the objective lens and the image lens of lens 2 both have spherical surfaces; and the objective lens and the image lens of lens 3 both have freeform optical surfaces.

[0093] In some embodiments, the lens group 122 has 3 to 7 lenses, and the thickness of the lens group 122 is less than or equal to 6 mm.

[0094] In this embodiment, the lens group 122 has 3 to 7 lenses. This design ensures that the lens group 122 has sufficient optical correction capability without making the structure too complex and resulting in excessive cost.

[0095] In this embodiment, the thickness of the lens group 122 is controlled within a range of 6mm, which can reduce the volume occupied by the optical imaging module 100 in the portable electronic device. Within a limited space, by reasonably controlling the thickness of the lens group 122, the size of the optical imaging module 100 can be effectively reduced, making it easier to integrate into mobile electronic devices such as smartphones, while meeting the requirements of optical performance.

[0096] In some embodiments, the second imaging lens 120 has a half field of view greater than or equal to 61°.

[0097] In this embodiment, the second imaging lens 120 has a half-field of view greater than or equal to 61°, which enables the second imaging lens 120 to acquire wider scene information and provide more comprehensive data support for distortion correction of the first visual image. In actual shooting, a larger half-field of view can capture more information about the surrounding environment, helping the processor to more accurately determine the distortion in the image and perform more effective correction.

[0098] In this embodiment, the half-field of view of the first imaging lens 110 is typically about 60°, and the half-field of view of the second imaging lens 120 is slightly larger than that of the first imaging lens 110. By incorporating this feature, the second field of view can encompass the first field of view. That is, the environmental range captured by the second visual image includes the environmental range captured in the first visual image.

[0099] In some embodiments, the total length of the first imaging lens 110 is TTL_D, the image height is IMH_D, the field of view is FIE_D, and the aperture value is FNO_D; wherein, TTL_D / 2*IMH_D<0.6, IMH_D≥5.16mm, and TTL_D≤5.8mm.

[0100] In this embodiment, TTL_D / 2*IMH_D < 0.6. This ratio is set to control the size and performance balance of the first imaging lens 110 while ensuring a certain image quality. IMH_D ≥ 5.16 mm ensures that the first imaging lens 110 can acquire a sufficiently large image to guarantee image detail and information content. TTL_D ≤ 5.8 mm limits the length of the first imaging lens 110 to prevent it from being too long, which would make the optical imaging module 100 too large and affect the overall design and portability of the device.

[0101] In addition, the total length of the first imaging lens also directly affects the size of the camera module. When the total length of the first imaging lens is relatively small, when it is mounted on a smart device, the first imaging lens does not protrude from the body of the smart device or only slightly protrudes from the body of the smart device, making the smart device look more aesthetically pleasing as a whole. In addition, it can also make the smart device more portable.

[0102] In some embodiments, let the total length of the second imaging lens 120 be TTL_X, the image height be IMH_X, the field of view be FIE_X, the absolute value of the maximum optical distortion be DIS_X, and the aperture value be FNO_X; where TTL_X ≤ TTL_D, FIE_X ≥ FIE_D, DIS_X ≤ 0.5%, IMH_X < IMH_D, IMH_X ≥ 2.2 mm, FNO_X ≤ FNO_D.

[0103] In this embodiment, TTL_X ≤ TTL_D ensures that the length of the second imaging lens 120 does not exceed that of the first imaging lens 110, which helps to control the volume of the entire optical imaging module 100. FIE_X ≥ FIE_D makes the field of view range of the second imaging lens 120 greater than or equal to that of the first imaging lens 110, so as to provide data support with a broader perspective for the distortion correction of the first visual image. DIS_X ≤ 0.5% strictly controls the maximum optical distortion of the second imaging lens 120 to ensure the accuracy and stability of its imaging. IMH_X < IMH_D, that is, the image height of the second imaging lens 120 is less than that of the first imaging lens 110, making the field of view range of the second imaging lens 120 greater than that of the first imaging lens 110. IMH_X ≥ 2.2 mm ensures that the second imaging lens 120 can form an image with a certain size and amount of information. FNO_X ≤ FNO_D makes the light passing amount of the second imaging lens 120 not lower than that of the first imaging lens 110 to meet the light requirements for imaging.

[0104] In some embodiments, the distance between the second imaging lens 120 and the first imaging lens 110 is less than or equal to a preset threshold.

[0105] In this embodiment, the distance between the second imaging lens 120 and the first imaging lens 110 is less than or equal to a preset threshold. In other words, the distance between the two parallel lines—the optical axis of the first imaging lens 110 and the optical axis of the second imaging lens 120—is kept as close as possible to the preset threshold. This design helps reduce the parallax between the imaging results of the first imaging lens 110 and the second imaging lens 120, resulting in a higher correlation between the image information acquired by the two lenses. When performing distortion correction on the first visual image, the information in the second visual image can be better utilized, improving the accuracy and effectiveness of distortion correction. Simultaneously, the smaller lens spacing also helps reduce the overall size of the optical imaging module 100, making it more compact and easier to integrate into mobile electronic devices.

[0106] In this embodiment, the first imaging lens 110 and the second imaging lens 120 are arranged sequentially along the first direction aa. It is understood that in other embodiments, the first imaging lens 110 and the second imaging lens 120 are arranged sequentially along a direction that is not in the same direction as the first direction aa.

[0107] In this embodiment, the first imaging lens 110 and the second imaging lens 120 are adjacent to each other. It is understood that in other embodiments, the distance between the first imaging lens 110 and the second imaging lens 120 is less than or equal to 10 mm.

[0108] In one specific embodiment, when the first imaging lens 110 starts working, the second imaging lens 120 is turned on simultaneously and provides the processor with a nearly distortion-free grayscale image (second visual image) generated by the second imaging lens 120. The processor can call a distortion correction algorithm to correct the first visual image according to the second visual image and display it on the display module of the portable electronic device in real time.

[0109] Another embodiment of the present invention provides a portable electronic device including the optical imaging module described in the above embodiments.

[0110] The optical imaging module of the aforementioned portable electronic device achieves effective image distortion correction through a unique dual-lens design: a first imaging lens and a second imaging lens, working in conjunction with the processor. The first imaging lens acquires light within a first field of view and forms a first visual image. This image typically contains rich scene information but suffers from significant geometric distortion due to its large field of view. The second imaging lens, on the other hand, forms a second visual image based on light within a second field of view. Its target surface is smaller than that of the first imaging lens, and the second field of view encompasses the first field of view. This design allows the second imaging lens to acquire image information from a wider angle, providing more data support for subsequent distortion correction. The processor, as the core of the system, performs distortion correction on the first visual image based on the second visual image to obtain the target image. In this way, the advantages of both lenses are fully utilized, compensating for the shortcomings of a single lens, reducing the degree of image distortion at large angles, and effectively improving image quality.

[0111] The optical imaging module of the aforementioned portable electronic device, by relaxing the distortion characteristics of the first imaging lens, reduces the thickness of the first imaging lens, thereby reducing the overall thickness of the optical imaging module. When mounted on a portable electronic device, it may not protrude from the device's body, or may only protrude slightly, making the device more aesthetically pleasing and portable.

[0112] The aforementioned portable electronic device has seen a significant improvement in its shooting capabilities. Through the dual-lens design of the optical imaging module and the distortion correction function of the processor, the portable electronic device can capture clearer, more accurate images with less distortion, meeting users' demands for high-quality imaging. Whether for everyday recording or professional photographic creation, users can obtain a better shooting experience with this portable electronic device. In travel photography, users can utilize its wide field of view and distortion correction function to capture expansive yet undistorted landscape photos; in portrait photography, it also ensures the true proportions of the subject's face and body, presenting a more natural effect.

[0113] When the first imaging lens starts working, the second imaging lens is turned on simultaneously and provides the processor with a nearly distortion-free grayscale image (second visual image) generated by the second imaging lens. The processor can call a distortion correction algorithm to correct the first visual image based on the second visual image and display it on the display module of the portable electronic device in real time.

[0114] Figure 3This is a schematic diagram of the structure of the second imaging lens provided in the first embodiment of the present invention. The optical imaging system includes, in sequence along the optical axis from the object side to the image side: a first lens L1, a second lens L2, a third lens L3, an aperture stop ST, a fourth lens L4, a fifth lens L5, a sixth lens L6, a filter, and an imaging plane IM. In this embodiment, the first imaging lens is a wide-angle lens; its parameters are not specifically described here.

[0115] The first lens L1 has negative optical power, with a convex object-side surface and a concave image-side surface. The second lens L2 has negative optical power, with both its object-side and image-side surfaces concave. The third lens L3 has negative optical power, with both its object-side and image-side surfaces concave. The fourth lens L4 has positive optical power, with a convex object-side surface and a concave image-side surface. The fifth lens L5 has positive optical power, with both its object-side and image-side surfaces convex. The sixth lens L6 has positive optical power, with both its object-side and image-side surfaces concave. The filter IR has both an object-side surface and an image-side surface. Light from the object passes sequentially through surfaces 1 to 15 and is ultimately imaged on the imaging plane IM.

[0116] As shown in Table 1, it is Figure 4 The table below shows the basic parameters of the optical imaging system in the representative embodiment, where the units for radius of curvature, thickness distance, and focal length are all millimeters (mm).

[0117] The FNO size of this embodiment is 2.5, and the half field of view (FOV) is 61°.

[0118] Table 1 Second Imaging Lens of the First Embodiment

[0119]

[0120] As shown in Table 2, it contains aspherical data from the embodiments represented in Table 1. This data can use the aspherical surface shown in Formula 1. However, the present invention is not limited to the aspherical polynomial form of this formula.

[0121] (Formula 1)

[0122] Where c is the paraxial curvature of the aspheric surface; k is the conic constant; r is the radial coordinate, representing the radial distance from the optical axis; z is the aspheric surface's elevation at a radial distance r along the optical axis. Ai is the i-th order aspheric coefficient.

[0123] Table 2 Aspheric coefficients of each lens surface in the second imaging lens of the first embodiment

[0124]

[0125] Figure 4The diagram shown is a distortion diagram of the embodiment represented in Table 1. The overall distortion is less than 0.3%, and the distortion at this scale is difficult to detect with the naked eye during actual imaging.

[0126] Figure 5 This is a schematic diagram of the structure of the second imaging lens provided in the second embodiment of the present invention. The optical imaging system includes, in sequence along the optical axis from the object side to the image side: a first lens L7, a second lens L8, an aperture stop ST, a third lens L9, a fourth lens L10, a fifth lens L11, a filter, and an imaging plane IM. In this embodiment, the first imaging lens is a wide-angle lens, and its parameters are not specifically described here. Therefore, the almost distortion-free second visual image generated by this second imaging lens can be used to correct the distortion of the first visual image.

[0127] The first lens L7 has negative optical power, with a convex object-side surface and a concave image-side surface. The second lens L8 has positive optical power, with a convex object-side surface and a concave image-side surface. The third lens L9 has positive optical power, with a concave object-side surface and a convex image-side surface. The fourth lens L10 has negative optical power, with a concave object-side surface and a convex image-side surface. The fifth lens L11 has positive optical power, with a convex object-side surface and a concave image-side surface. The filter IR has an object-side surface and an image-side surface. Light from the object passes sequentially through surfaces 1 to 15 and is finally imaged on the imaging surface IM.

[0128] As shown in Table 3, it is Figure 5 The table below shows the basic parameters of the optical imaging system in the representative embodiment, where the units for radius of curvature, thickness distance, and focal length are all millimeters (mm).

[0129] The FNO size of this embodiment is 2.8, and the half field of view (FOV) is 61°.

[0130] Table 3 Second Imaging Lens in the Second Embodiment

[0131]

[0132] In the embodiments represented in Table 3, aspherical surfaces were used on any surface of any lens. Table 4 shows the aspherical data for the embodiments represented in Table 3. It includes the conic coefficients and aspherical coefficients of each order for each aspherical surface.

[0133] Table 4 Aspheric coefficients of each lens surface in the second imaging lens of the second embodiment.

[0134]

[0135] Figure 6The diagram shown in Table 3 illustrates the distortion of the embodiment represented by the image. The overall distortion is less than 0.3%, a level of distortion that is practically imperceptible to the naked eye during actual imaging. Therefore, the almost distortion-free second visual image generated by this second imaging lens can be used to correct the distortion of the first visual image.

[0136] The third embodiment of the present invention provides an optical imaging module 100, including a first imaging lens 110 (a large-area, large-distortion imaging lens) (e.g. Figure 7-a (as shown) and the second imaging lens 120 (small target surface, smaller distortion imaging lens) (as shown) Figure 7-b As shown in the figure, the images from the two lenses are fused using the image correction method described in the above embodiment, thereby enabling the optical imaging module to obtain a high-quality image with minimal distortion.

[0137] In this embodiment, the large-target-area, large-distortion imaging lens comprises five lenses, arranged sequentially from the object side to the image side as follows: aperture D1ST1, first lens D1L1, second lens D1L2, third lens D1L3, fourth lens D1L4, fifth lens D1L5, filter D1F1, and image sensor D1S1. The first lens D1L1 has positive optical power, with a convex object side and a concave image side; the second lens D1L2 has negative optical power, with a convex object side and a concave image side; the third lens D1L3 has positive optical power, with a concave object side and a convex image side; the fourth lens D1L4 has positive optical power, with a concave object side and a convex image side; the fifth lens D1L5 has negative optical power, with a concave object side and a concave image side; and the filter D1F1 has both an object side and an image side. Light from the object passes sequentially through the surfaces of the lens group and is eventually imaged onto the imaging surface of the image sensor D1S1.

[0138] The small-target-area, low-distortion imaging lens also comprises five lenses, arranged sequentially from the object side to the image side: aperture X1ST1, first lens X1L1, second lens X1L2, third lens X1L3, fourth lens X1L4, fifth lens X1L5, filter X1F1, and image sensor X1S1. The first lens X1L1 has positive optical power, with a convex object side and a concave image side; the second lens X1L2 has negative optical power, with a convex object side and a concave image side; the third lens X1L3 has positive optical power, with a concave object side and a convex image side; the fourth lens X1L4 has positive optical power, with a concave object side and a convex image side; the fifth lens X1L5 has negative optical power, with a concave object side and a concave image side; and the filter X1F1 has both an object side and an image side. Light from the object passes sequentially through the surfaces of the lens group and is ultimately imaged onto the imaging surface of the image sensor X1S1.

[0139] The large-target-area, large-distortion imaging lens has a total length of TTL_D1, an image height of IMH_D1, an object-side field of view of FIE_D1, and an aperture of FNO_D1. The small-target-area, small-distortion imaging lens has a total length of TTL_X1, an image height of IMH_X1, an object-side field of view of FIE_X1, and an aperture of FNO_X1.

[0140] In this embodiment, TTL_D1=5.80mm, IMH_D1=5.38mm, FIE_D1=88.56°, FNO_D1=1.77; TTL_X1=3.32mm, IMH_X1=2.65mm, FIE_X1=88.56°, FNO_X1=1.77.

[0141] As can be seen, the ratio of the total length of a large-area, high-distortion imaging lens to the diagonal length of its image sensor is TTL_D / 2*IMH_D = 0.539, while the ratio of the total length of a small-area, low-distortion imaging lens to the diagonal length of its image sensor is TTL_X / 2*IMH_X = 0.626. In related technologies, the ratio of the total length of the lens to the diagonal length of its image sensor is generally greater than 0.65. In this embodiment, the lens design relaxes the distortion index to reduce the total length of the lens, thereby meeting the requirements for thinner and lighter portable electronic devices.

[0142] In this embodiment, the object-side field of view and aperture value of both lenses are designed to be the same. This is to facilitate the later use of distortion correction algorithms. Generally, the following relationships can be held: FIE_D1≤FIE_X1, FNO_D1≥FNO_X1. That is, the field of view of the smaller target-area, smaller distortion imaging lens should cover the field of view of the larger target-area, larger distortion imaging lens, and the aperture value of the smaller target-area, smaller distortion imaging lens should be smaller than the aperture value of the larger target-area, larger distortion imaging lens. The purpose of the smaller target-area, smaller distortion imaging lens covering the field of view of the larger target-area, larger distortion imaging lens is to enable distortion correction for the entire field of view imaged by the larger target-area, larger distortion imaging lens. The aperture value of a small-aperture, smaller-distortion imaging lens is no greater than that of a large-aperture, larger-distortion imaging lens. This means that a small-aperture, smaller-distortion imaging lens has a larger aperture than a large-aperture, larger-distortion imaging lens, and can capture more details of the imaged object during imaging. Therefore, it can be better used to correct distortion of images captured by large-aperture, larger-distortion imaging lenses.

[0143] In addition, TTL_D1 is required to be greater than TTL_X1, which means that the total length of the small target surface with smaller distortion imaging lens is not greater than the total length of the large target surface with larger distortion imaging lens. This ensures that the thickness of the entire imaging module does not exceed the thickness of the large target surface with larger distortion imaging lens, thereby achieving an ultra-thin design for the entire optical imaging module.

[0144] For convenience, the aspherical surfaces of the above-mentioned lens surfaces are as shown in the calculation formula 2 below. However, this embodiment is not limited to the aspherical polynomial form represented by the calculation formula 2.

[0145] (Formula 2)

[0146] Where k is the conic coefficient, A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 are aspheric coefficients, c is the curvature at the center of the optical surface, r is the perpendicular distance between a point on the aspheric curve and the optical axis, z is the aspheric depth, which is the perpendicular distance between a point on the aspheric surface at a distance r from the optical axis and a tangent surface at the vertex of the aspheric optical axis.

[0147] Table 5 is... Figure 7-a Detailed data for medium-to-large target surface imaging lenses with significant distortion are provided, where the units for radius of curvature, thickness, and focal length are in mm, and surfaces 0-14 sequentially represent the surfaces from the object side to the image side. Table 6 shows... Figure 7-a The aspherical data of each lens surface in the large-scale target-surface large-distortion imaging lens, where k represents the conic coefficient in the aspherical curve calculation formula (2), and A13-A30 represent the 13th-30th order aspherical coefficients of each surface.

[0148] Table 7 is... Figure 7-b Detailed structural data for small-to-medium target surface imaging lenses with smaller distortion are provided, where the units for radius of curvature, thickness, and focal length are mm, and surfaces 0-14 sequentially represent the surfaces from the object side to the image side. Table 8 shows... Figure 7-b The aspherical data of each lens surface in the small-target-area small-distortion imaging lens, where k represents the conic coefficient in the aspherical curve calculation formula (2), and A13-A30 represent the 13th-30th order aspherical coefficients of each surface.

[0149] Table 5. Large-area lens with significant distortion in the third embodiment.

[0150]

[0151] Table 6 Aspheric coefficients of each lens surface in the large-target-area, large-distortion lens of the third embodiment.

[0152]

[0153]

[0154]

[0155] Table 7. Small Target Surface and Small Distortion Lens in the Third Embodiment

[0156]

[0157] Table 8 Aspheric coefficients of each lens surface in the small-target-area, small-distortion lens of the third embodiment.

[0158]

[0159]

[0160] Figure 8-a The graph shows the distortion rate of a large-area, large-distortion imaging lens as a function of the object-side field of view. It can be seen from the graph that the distortion rate of the large-area, large-distortion imaging lens increases monotonically with the increase of the field of view, but at the maximum field of view, the distortion rate still does not exceed 5%. Figure 9-a The graph shows the distortion rate of a small-aperture, low-distortion imaging lens as a function of the object-side field of view. It can be seen that the distortion rate of the small-aperture, low-distortion imaging lens increases monotonically with the increase of the field of view, but at the maximum field of view, the distortion rate still does not exceed 0.5%, which is an order of magnitude smaller than that of a large-aperture, high-distortion imaging lens. This ultra-low distortion characteristic of the small-aperture, low-distortion imaging lens is beneficial for us to use algorithms to correct the distortion of images formed by large-aperture, high-distortion imaging lenses in later stages, thereby ultimately obtaining a high-quality image with ultra-low distortion.

[0161] Figure 8-b The diagram shows the transverse chromatic aberration of light with wavelengths of 650nm, 610nm, 555nm, 510nm, 470nm, and 435nm after passing through a large-area, highly distorted imaging lens. Figure 8-c It also shows the axial spherical aberration diagram after light with a wavelength of 555nm passes through a large-surface, highly distorted imaging lens. Figure 9-b The diagram shows the transverse chromatic aberration of light with wavelengths of 650nm, 610nm, 555nm, 510nm, 470nm, and 435nm after passing through a small-target, low-distortion imaging lens. Figure 9-c The image also shows the axial spherical aberration after light with a wavelength of 555nm passes through a small-target imaging lens with minimal distortion. As can be seen from the image, the variations in transverse chromatic aberration and axial spherical aberration, whether in the first or second imaging lens, are very small and can be ignored across different fields of view.

[0162] When the distortion of a small-target-area, small-distortion imaging lens is relatively small, the distortion rate of the generated second-view image is also relatively small. Using this as a guide, the distortion of a large-target-area, large-distortion imaging lens is corrected. That is, the first-view image is corrected using a second-view image with almost no distortion. This can also reduce the distortion rate of the large-target-area, large-distortion imaging lens to a certain extent, thus enabling the optical imaging module to generate images with high quality and low distortion.

[0163] The fourth embodiment of the present invention provides an ultra-thin, ultra-small distortion, high-performance optical imaging module, including a large target surface and a large distortion imaging lens (such as...). Figure 10-a (as shown) and a small-target, smaller-distortion imaging lens (such as) Figure 10-b As shown, the image from the two lenses is fused using an algorithm, thus enabling the acquisition of a high-quality image with minimal distortion through this ultra-thin, ultra-small distortion, high-performance optical imaging module.

[0164] In this embodiment, the large target area and large distortion imaging lens is the same as that in the first embodiment, and will not be described again here.

[0165] The small target surface and small distortion imaging lens also includes 6 lenses, which are arranged from the object side to the image side as follows: first lens X2L1, second lens X2L2, aperture X2ST1, third lens X2L3, fourth lens X2L4, fifth lens X2L5, sixth lens X2L6, filter X2F1 and image sensor X2S1. The first lens X2L1 has negative optical power, with a concave object-side surface and a convex image-side surface; the second lens X2L2 has negative optical power, with a convex object-side surface and a concave image-side surface; the third lens X2L3 has positive optical power, with a convex object-side surface and a convex image-side surface; the fourth lens X2L4 has positive optical power, with a convex object-side surface and a convex image-side surface; the fifth lens X2L5 has negative optical power, with a concave object-side surface and a convex image-side surface; the sixth lens X2L6 has negative optical power, with a concave object-side surface and a concave image-side surface; the filter X2F1 has both an object-side surface and an image-side surface. Light from the object passes sequentially through the surfaces of the lens group and is finally imaged onto the imaging surface of the image sensor X2S1.

[0166] The total length of the small-target-area, low-distortion imaging lens is TTL_X2, the image height is IMH_X2, the object-side field of view is FIE_X2, and the aperture value is FNO_X2. In this embodiment, TTL_X2 = 5.5mm, IMH_X2 = 2.61mm, FIE_X2 = 88.5 degrees, and FNO_X2 = 1.77.

[0167] Therefore, we have: FIE_X2=FIE_D1, FNO_X2=FNO_D1, TTL_X2<TTL_D1, which meets the design requirements.

[0168] Table 9 is... Figure 10-b Detailed data for small-to-medium target surface imaging lenses with smaller distortion, where the units for radius of curvature, thickness, and focal length are mm, and surfaces 0-16 sequentially represent the surfaces from the object side to the image side. Table 10 shows... Figure 10-bThe aspherical data of each lens surface in the small-to-medium-sized target surface with small distortion imaging lens, where k represents the conic coefficient in the aspherical curve calculation formula (2), and A13-A30 represent the 13th to 30th order aspherical coefficients of each surface.

[0169] Table 9. Fourth embodiment: small target area, smaller distortion lens

[0170]

[0171] Table 10 Aspherical coefficients of each lens surface in the small target area and small distortion lens of the fourth embodiment

[0172]

[0173]

[0174]

[0175] Figure 11-a The graph shows the distortion rate of a small-aperture, low-distortion imaging lens as a function of the object-side field of view. It can be seen that the distortion rate of the small-aperture, low-distortion lens increases monotonically with the increase of the field of view, but at the maximum field of view, the distortion rate still does not exceed 0.03%, which is two orders of magnitude smaller than that of a large-aperture, high-distortion imaging lens. This ultra-low distortion characteristic of the small-aperture, low-distortion lens is beneficial for us to use algorithms to correct the distortion of images formed by large-aperture, high-distortion lenses in later stages, thereby ultimately obtaining a high-quality image with ultra-low distortion.

[0176] Figure 11-b The diagram shows the transverse chromatic aberration of light with wavelengths of 650nm, 610nm, 555nm, 510nm, 470nm, and 435nm after passing through a small-target, low-distortion imaging lens. Figure 11-c It also shows the axial spherical aberration map after light with a wavelength of 555nm passes through a small-target, low-distortion imaging lens.

[0177] The fifth embodiment of the present invention provides an ultra-thin, ultra-small distortion, high-performance optical imaging module, including a large target surface and a large distortion imaging lens (such as...). Figure 12-a (as shown) and a small-target, smaller-distortion imaging lens (such as) Figure 12-b As shown, the image from the two lenses is fused using an algorithm, thus enabling the acquisition of a high-quality image with minimal distortion through this ultra-thin, ultra-small distortion, high-performance optical imaging module.

[0178] In this embodiment, the large target area and large distortion imaging lens is the same as that in the first embodiment, and will not be described again here.

[0179] The small target surface and small distortion imaging lens comprises 6 lenses, which are arranged from the object side to the image side as follows: first lens X3L1, second lens X3L2, aperture X3ST1, third lens X3L3, fourth lens X3L4, fifth lens X3L5, sixth lens X3L6, filter X3F1 and image sensor X3S1. The first lens X3L1 has negative optical power, with both its object-side and image-side surfaces being concave. The second lens X3L2 has positive optical power, with both its object-side and image-side surfaces being convex. The third lens X3L3 has positive optical power, with both its object-side and image-side surfaces being convex. The fourth lens X3L4 has positive optical power, with both its object-side and image-side surfaces being convex. The fifth lens X3L5 has negative optical power, with both its object-side and image-side surfaces being concave. The sixth lens X3L6 has positive optical power, with both its object-side and image-side surfaces being convex. The filter X3F1 has both an object-side and an image-side surface. Light from the object passes sequentially through the surfaces of the lens group and is ultimately imaged onto the imaging surface of the image sensor X3S1.

[0180] The total length of the small-target-area, low-distortion imaging lens is TTL_X3, the image height is IMH_X3, the object-side field of view is FIE_X3, and the aperture value is FNO_X3. In this embodiment, TTL_X3 = 5.5 mm, IMH_X3 = 2.4 mm, FIE_X3 = 120 degrees, and FNO_X3 = 1.77.

[0181] Therefore, we have: FIE_X3 > FIE_D1, FNO_X3 = FNO_D1, TTL_X3 < TTL_D1, which meets the design requirements.

[0182] Table 11 is... Figure 12-b Detailed data for small-to-medium target surface imaging lenses with smaller distortion, where the units for radius of curvature, thickness, and focal length are mm, and surfaces 0-16 sequentially represent the surfaces from the object side to the image side. Table 12 shows... Figure 12-b The aspherical data of each lens surface in the small-to-medium-sized target surface with small distortion imaging lens, where k represents the conic coefficient in the aspherical curve calculation formula (2), and A13-A30 represent the 13th to 30th order aspherical coefficients of each surface.

[0183] Table 11. Lens with smaller target area and less distortion in the third embodiment.

[0184]

[0185] Table 12 Aspheric coefficients of each lens surface in the small-target-area, low-distortion lens of the third embodiment.

[0186]

[0187]

[0188]

[0189] Figure 13-a The graph shows the distortion rate of a small-aperture, low-distortion imaging lens as a function of the object-side field of view. It can be seen that the distortion rate of the small-aperture, low-distortion imaging lens increases monotonically with the increase of the field of view, but at the maximum field of view, the distortion rate does not exceed 0.3%, which is an order of magnitude smaller than that of a large-aperture, high-distortion imaging lens. This ultra-low distortion characteristic of the small-aperture, low-distortion imaging lens is beneficial for us to use algorithms to correct the distortion of images formed by large-aperture, high-distortion lenses in later stages, thereby ultimately obtaining a high-quality image with ultra-low distortion.

[0190] The second imaging lens in the above embodiment needs to be used in conjunction with the adjacent first imaging lens. Because the second imaging lens only needs to acquire a reference image with almost no distortion, its overall size can be designed to be small, occupying less space in mobile devices. Subsequently, a background algorithm performs distortion correction on the image from the first imaging lens and processes the parallax between the two to obtain a high-quality image with minimal distortion. Please refer to [link to relevant documentation]. Figure 14 , Figure 14 The image shows a clear and distortion-free target image (c) obtained by a processor after the distortion correction process of a first visual image (a) with distortion but clear, obtained by a first imaging lens and a second visual image (b) with lower clarity but almost no distortion, obtained by a second imaging lens.

[0191] It should be noted that the term "comprising" and its variations used in the embodiments of this invention are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "a plurality" mentioned in the embodiments of this invention are illustrative and not restrictive, and those skilled in the art should understand that unless explicitly indicated otherwise in the context, they should be understood as "one or more".

[0192] The user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in the embodiments of this invention are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0193] In this invention, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "height," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of simplifying the description of this application and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. In other words, they should not be construed as limitations on this application.

[0194] In this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating the relative importance of the indicated features or the number of indicated technical features. Therefore, a feature defined as "first" or "second" can explicitly include at least one of that feature. In this application, "a plurality of" means at least two, such as two, three, etc.; "several" means at least one, such as one, two, three, etc., unless otherwise explicitly specified.

[0195] In this invention, unless otherwise explicitly defined, the terms "installation," "connection," "linking," "fixing," and "setting," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can also refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0196] In this invention, unless otherwise explicitly defined, the terms "above," "on top of," "over," "above," "below," "below," "below," or "below" for "first feature above second feature" can refer to the first and second features being in direct contact, or to the first and second features being in indirect contact through an intermediate medium. Furthermore, "above," "over," and "below" for "first feature above second feature" can mean the first feature is directly above or diagonally above the second feature, or simply indicates that the horizontal height of the first feature is higher than the horizontal height of the second feature. Similarly, "below," "below," and "below" for "first feature below second feature" can mean the first feature is directly below or diagonally below the second feature, or simply indicates that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0197] It should be understood that the above embodiments are exemplary and are not intended to include all possible embodiments covered by the claims. Various modifications and changes can be made to the above embodiments without departing from the scope of this disclosure. Similarly, the various technical features of the above embodiments can be arbitrarily combined to form other embodiments of this application that may not be explicitly described. Therefore, the above embodiments only illustrate several embodiments of this application and do not limit the scope of protection of this patent application.

Claims

1. An optical imaging module, characterized in that, include: First imaging lens; The first imaging lens is configured to form a first visual image based on light within a first field of view; Second imaging lens; The second imaging lens is configured to form a second visual image based on light within a second field of view; wherein the target surface size of the second imaging lens is smaller than the target surface size of the first imaging lens; and the second field of view includes the first field of view. A processor configured to perform distortion correction on the first visual image based on the second visual image to obtain a target image.

2. The optical imaging module according to claim 1, characterized in that, The second imaging lens includes a filter; the filter is used to project light within a preset wavelength range onto the image plane of the second imaging lens.

3. The optical imaging module according to claim 2, characterized in that, The second visual image is a grayscale image.

4. The optical imaging module according to claim 1, characterized in that, The second imaging lens includes a lens group; The lens group includes multiple lenses; each of the multiple lenses includes an objective lens and an image lens; light within the second field of view passes sequentially through the objective lens and image lens of each lens and is then projected onto the image plane of the second imaging lens; wherein, the multiple lenses are coaxially arranged.

5. The optical imaging module according to claim 4, characterized in that, The objective lens surface shape includes at least one of the following: spherical, aspherical, or freeform optical surface; and / or, The surface shape of the image mirror includes at least one of the following: spherical, aspherical, or freeform optical surface.

6. The optical imaging module according to claim 4, characterized in that, The lens group has 3 to 7 lenses, and the thickness of the lens group is less than or equal to 6 mm.

7. The optical imaging module according to claim 1, characterized in that, The second imaging lens has a half field of view greater than or equal to 61°.

8. The optical imaging module according to claim 1, characterized in that, Let the total length of the first imaging lens be TTL_D, the image height be IMH_D, the field of view be FIE_D, and the aperture value be FNO_D; Among them, TTL_D / 2*IMH_D<0.6, IMH_D≥5.16mm, and TTL_D≤5.8mm.

9. The optical imaging module according to claim 1, characterized in that, Let the total length of the second imaging lens be TTL_X, the image height be IMH_X, the field of view be FIE_X, the absolute value of the maximum optical distortion be DIS_X, and the aperture value be FNO_X; Where TTL_X ≤ TTL_D, FIE_X ≥ FIE_D, DIS_X ≤ 0.5%, IMH_X <IMH_D,IMH_X≥2.2mm,FNO_X≤FNO_D。 10. The optical imaging module according to any one of claims 1 to 9, characterized in that, The distance between the second imaging lens and the first imaging lens is less than or equal to a preset threshold.

11. A portable electronic device, characterized in that, The portable electronic device includes an optical imaging module as claimed in any one of claims 1 to 10.

Images