The main parameters of the Line scanning lens include the following key indicators:
Resolution
Resolution is a critical parameter for evaluating a lens's ability to capture fine image details, typically expressed in line pairs per millimeter (lp/mm). Lenses with higher resolution can produce clearer imaging results. For example, a 16K line scan lens may have up to 8,192 horizontal pixels and a resolution of 160 lp/mm. Generally, the higher the resolution, the smaller the object that can be distinguished, resulting in sharper images.
Pixel Size
Pixel size is measured in micrometers (μm) and directly influences lateral resolution. It refers to the maximum sensor size or the dimensions of the image plane that the lens can cover. When using a line scan lens, it is essential to select one that matches the camera sensor size to fully utilize the effective pixels and achieve high-quality images. For instance, a lens with a pixel size of 3.5 μm is capable of preserving more detail during scanning, whereas a 5 μm pixel size is more suitable for applications requiring a larger scanning range.
Optical Magnification
The optical magnification of line scanning lenses typically ranges from 0.2x to 2.0x, depending on the lens design. Specific magnification values, such as those ranging from 0.31x to 0.36x, are suitable for various inspection tasks.
Focal Length
Focal length determines the field of view and imaging range. Fixed-focus lenses require careful selection based on the working distance, while zoom lenses offer flexibility by allowing adjustment of the focal length to accommodate different application scenarios.
Interface Type
Common lens interfaces include C-mount, CS-mount, F-mount, and V-mount. These must be compatible with the camera interface to ensure proper installation and functionality. For example, F-mount lenses are commonly used in industrial inspection equipment.
Working Distance
Working distance refers to the distance between the front of the lens and the surface of the object being imaged. This parameter varies significantly across different lens models and should be selected according to the specific application. For instance, a scanning head with a maximum working distance of 500 mm is ideal for non-contact measurement tasks.
Depth of Field
Depth of field indicates the range in front of and behind the object within which a sharp image is maintained. It is typically influenced by factors such as aperture, focal length, and shooting distance. For example, a depth of field extending up to 300 mm can ensure high measurement accuracy.
Recommendations for Selecting Line Scanning Lenses:
1. Clarify Imaging Requirements: Determine key parameters such as resolution, field of view, maximum image area, and working distance based on the intended application. For example, high-resolution line scanning lenses are recommended for applications requiring detailed imaging, while lenses with a wider field of view are suitable for capturing large objects.
2. Understand Object Dimensions: Select an appropriate scanning length based on the size of the object being inspected.
3. Imaging Speed: Choose a line scan lens that supports the required imaging speed. In high-speed applications, lenses capable of supporting high frame rates should be selected.
4. Environmental Conditions: Consider environmental factors such as temperature, humidity, and dust levels, and choose a lens that meets these operational requirements.
Additional Parameters to Consider:
Conjugate Distance: This refers to the total distance from the object to the lens and from the lens to the image sensor. A shorter conjugate distance results in a smaller imaging range.
Relative Illuminance: This parameter represents the ratio of optical transmittance across different areas of the lens. It significantly affects the uniformity of image brightness and optical distortion.
In conclusion, selecting an appropriate line-scan lens requires a comprehensive evaluation of multiple technical specifications and application-specific requirements. Choosing the most suitable lens for the intended use case enhances imaging quality and system efficiency, ultimately leading to optimal imaging performance.
Post time: Jul-28-2025