Aspheric lens technology is currently one of the most popular topics.In fact, aspheric lens technology has been widely used for photographic purposes and was introduced into CCTV lenses about 10 years ago.So what is an aspheric lens?

In fact, aspheric lenses are usually spherical rather than flat to the naked eye.This is because the surface shape of the aspheric lens can be obtained by fine-tuning based on the spherical shape.From a mathematical point of view, spherical functions are quadratic functions, but non-spherical functions are functions of order 4 or higher, usually designed to be ten times larger, so non-spherical functions are more complicated.More clearly, the aspheric shape is based on the spherical shape and is manually controlled based on the spherical shape.Because the pre-designed fine surface shape is wavy, the surface shape of the lens shows a complex aspheric surface.Each aspheric opening has a different power.

It is generally believed that after passing through a convex lens (the most common spherical lens), the beam of light can be focused on a single point.For example, many people use magnifying glasses to collect sunlight and burn paper to play.However, from an optical point of view, a spherical convex lens cannot actually collect light to this point.What it collects is actually a highlight.Due to limited visibility, it is a bit visible to the naked eye.This is because the spherical mirror has a congenital defect, a defect called “spherical aberration", which cannot be overcome by a single spherical mirror.It is this abnormality that causes flares.This aberration has a significant impact on image quality.However, aspheric lenses can accurately converge light to a position greater than the spherical aberration, thereby greatly improving the imaging quality.So, what are the specific advantages of using aspheric lenses for lenses?

(1) The application of aspheric lenses makes the optical structure of the lens relatively simple, and it is easy to obtain a large aperture in the optical design and mechanical structure, thereby brightening the entire image.

(2) Aspheric lenses greatly improve image quality and enhance the clarity of images (especially edge images).

Applying aspheric surfaces to surfaces with higher primary light can also correct off-axis aberrations, such as astigmatism and distortion.This greatly improves off-axis imaging.This is very important in actual use.This can clearly express all the details of the image and avoid helpless situations where the image cannot be used as evidence.

(3) Aspheric lenses can replace a set of spherical lenses, so the size of the lens can be reduced by using aspheric lenses.

Using advanced optical software, the design of aspheric lenses is not difficult, but its manufacturing and processing require very high technology and craftsmanship.Therefore, few manufacturers have been able to complete the development and production of all aspheric lenses for CCTV lenses.The development and production technology of aspheric lenses has become the company's core technology.