In the process of industrial production towards intelligence and automation, industrial vision technology plays a pivotal role, from the production inspection of precision parts to the monitoring of complex assembly processes, are inseparable from its accurate “insight”. The lens, as the core component of the industrial vision system, like the human eye, directly determines the quality and breadth of the vision system to obtain information. Among the many types of lenses, industrial Varifocal Lens and Fixed Focus Lens play a key role in different industrial scenarios with their unique performance. How to make a choice between the two?

Principle Difference

( I ) Industrial Varifocal Lens

Industrial Varifocal Lens changes the focal length of the lens by changing the relative position between the lenses inside the lens. Simply put, when the lens internal lens group moves, the position where the light converges changes, thus realizing a continuous change in focal length. This design allows Varifocal Lens to zoom in or out to image the same object at different shooting distances in order to meet the needs of observing the details of objects and image acquisition in different scenes.

( II ) Principle of Fixed Focus Lens

A fixed-focus lens has a fixed focal length; it has only one fixed focal length value. Its imaging principle is based on the passage of light through a fixed position and combination of lens groups to form a clear image on the image sensor. Due to the fixed focal length, the optical structure of a fixed-focus lens is relatively simple, with less loss of light as it travels between the lenses, making it easier to obtain high-quality imaging.

Machine Vision Lens Advantages

( I ) Advantages of Industrial Varifocal Lens

1. High flexibility: you can capture objects of different distances and sizes by adjusting the focal length without changing the camera position. For example, in the production line inspection, not only can observe the overall appearance of the product, but also quickly pull the focus closer to view the local details of the product, without the need to frequently change the lens or adjust the camera position, greatly improving the inspection efficiency.

1. Wide range of applicable scenarios: applicable to the need for a variety of different sizes or distances from the object imaging scenarios. For example, in the field of security monitoring, it can not only monitor a large area of the scene, but also quickly varifocal to close-up the target when abnormalities are detected, meeting different monitoring needs.

( II ) Advantages of fixed-focus lenses

1. High image quality: due to the simple optical structure and relatively small number of lenses, problems such as aberration and chromatic aberration caused by light propagating between the lenses are easier to control, so it is possible to obtain higher resolution and clearer images. In the very high requirements for image quality of industrial inspection, such as electronic chip inspection, fixed-focus lens can clearly present the chip on the subtle circuit lines and defects, to ensure the accuracy of detection.

2. Lower cost: compared with the complex optical structure and manufacturing process of Varifocal Lens, the design and production of fixed-focus lens is less difficult, and the cost is more affordable. For some projects with limited budgets but with certain requirements for imaging quality, fixed-focus lenses are a cost-effective choice.

Machine Vision Lens Applications

（ I ）Industrial Varifocal Lens Applications

1. Intelligent Logistics Sorting: In logistics warehouses, industrial Varifocal Lens is installed on robotic arms to identify and locate parcels of different sizes and shapes. Through the varifocal function, the lens can quickly obtain the overall information of the parcels and barcode information, guide the robotic arm to accurately grab and sort the parcels, and improve the efficiency of logistics sorting.

1. Machine vision inspection: In the production line of automobile parts, it is necessary to measure the size and detect the defects of different types of parts. Industrial Varifocal Lens can flexibly adjust the focal length according to the size of the parts and the inspection requirements, and carry out comprehensive inspection of the parts to ensure that the product quality meets the standards.

（ II ）Fixed Focus Lens Applications

2. Electronic Manufacturing Inspection: In the manufacturing process of cell phone screens, fixed focus lenses are used to detect whether the pixel points on the screen have defects such as bad dots and bright spots. Due to the high imaging quality of the fixed focus lens, it can clearly distinguish tiny pixel defects and guarantee the production quality of cell phone screens.

2. Digital acquisition of cultural relics: In the field of cultural relics protection, high-precision digital acquisition of cultural relics is required to preserve the detailed information of cultural relics. With its excellent imaging capability, the fixed-focus lens can accurately restore the color and texture of cultural relics, providing high-quality data support for the digital protection of cultural relics.

Industrial Varifocal Lens and Fixed Focus Lens have their own advantages and disadvantages. If your application scenario requires frequent adjustments to the shooting angle and focal length, the pursuit of flexibility and wide applicability, then the industrial Varifocal Lens is a better choice; and if you pay more attention to the quality of the image, the sharpness of the image and the resolution of the requirements of the higher, and the application scenario is relatively fixed, fixed-focus lenses can meet your needs.