Free-form Lens
At the end of October, Huawei officially brings the Mate 40 Series mobile phones to China. Huawei Mate 40 series continued the Mate axis symmetrical design, the introduction of a very futuristic “starring design” as through the door of the stars. Explore the beauty of the future with a unique and instantly recognizable style.
Among them, the Huawei Mate 40 Pro+ comes with a 50-megapixel crown camera, 20-megapixel ultra-wide-angle lens, ToF lens, 8-megapixel 10X periscope, and 12-megapixel telephoto camera, which offers 17x optical zoom when compared to the ultra-wide-angle.
Besides, the new Huawei Mate 40 Pro+ phone’s ultra-wide-angle camera uses the industry’s first free-form lens, with a 20-megapixel ultra-wide-angle free-form camera that drastically reduces the deformation at the edges of the image to further recreate the real world as you see it.
The designer of Free-form Lens of Huawei
According to the information released by the Hangzhou University of Electronic Science and Technology, Huawei’s new mobile phone’s ultra-wide-angle camera uses the industry’s first free-form lens, which, according to Huawei Consumer CEO Richard Yu, “solves the problem of photo distortion, captures the true shape of the object, and can take the best portrait”. It is understood that the prototype designer of this free-form lens, Hou Changlun, associate professor of electronic information school of the university.
What is Freeform Lens?
Unlike traditional spherical and aspheric optics, optical-free-form surfaces are non-axisymmetric, irregular, and complex. By introducing freeform surfaces in an optical system, the optical system can be made more compact, lighter in weight, and have fewer optical-elements; and it can better correct the aberration of the optical system and improve the imaging quality. Smartphones have a broad market, which makes it possible for high-end devices to use cutting-edge optical components to enhance the user’s photographic experience.
Dr. Hou Changlun graduated from the Department of Optoelectronics, Zhejiang University, majoring in measurement technology and instrumentation, and has nearly 20 years of research experience in micro-optics, optical imaging, and optical inspection. He believes that low-precision freeform surfaces have been widely used in optical lighting systems to improve lighting uniformity and energy efficiency; with the rapid development of high-precision freeform surface processing and inspection technology, the application of freeform surfaces in high-precision imaging optical systems will become more and more widespread.
With the rapid development of high-precision freeform processing and inspection technology, the application of freeform optics in high-precision imaging optical systems will become more and more widespread. Freeform optical products have greatly expanded the application space and market demand will grow rapidly. Huawei mobile phone has become the “crab eater” of the use of freeform lenses, and Dr. Changlun Hou’s research.
It is understood that Changlun Hou has been involved in Huawei’s design since 2018. The first phase mainly verified the application research of free-form surfaces in ultra-wide-angle mobile phone lenses, focusing on the ability of free-form surfaces to correct the distortion of ultra-wide-angle mobile phone lenses, and through nearly a year of theoretical design and simulation, the expected goal was achieved: by introducing a free-form lens, a distortion-free ultra-wide-angle lens was designed.
The second phase mainly applied the research results of the first phase to the mass-produced Huawei’s Mate 40 mobile phone model, participated in the mass production of ultra-wide-angle lenses as a technical advisor to Huawei, and verified the parameters of the mass-produced ultra-wide-angle lenses, and communicated with the lens manufacturer about the free-form lens design processing and manufacturing technology. “Fortunately, the prototype design of the free-form lens we made can be put into application, and the specifications and parameters developed can be adopted,” Hou Changlun said.
In general, there is always a distance from technology development to industrial applications. But Huawei always maintains a high sensitivity to the frontier of technology and seizes the opportunity to transform technology into an upgraded user experience, creating higher value for users.
Benefits of Free-form Lens
The ultra-wide-angle lens in Huawei Mate 40 phones, thanks to the introduction of free-form surfaces. The image quality of the lens is very high, the optical distortion of the system is notably less, without the need to go through software distortion correction can be obtained without distortion of high-definition images, due to the required to correct the distortion, users can get and display the high-definition photos taken faster. It can achieve ultra-wide-angle lens distortion-free HD high-resolution video output, the ultra-wide-angle lens of other mobile phones due to the existence of optical distortion, shooting ultra-wide-angle HD video, can not real-time software to correct the video distortion and make the output video with obvious distortion. “This is a perfect link between research and engineering,” Dr. Changlun Hou said.
Huawei Free-form Lens 
Future uses of Free-form Lens
Besides exploring the application of freeform lenses in ultra-wide-angle lenses, Changlun Hou’s research team is also exploring the application of freeform surfaces in the built-in optical zoom system of mobile phones, and the research results have formed a series of papers: “Ultra-thin optical zoom system based on freeform surfaces” in IEEE Photonics Journal, “Ultra-thin optical zoom system based on freeform surfaces” in Optical Engineering of “Optical zoom system based on lateral movement of Alvarez free-form lenses”.
