Lens is the core component of optical imaging in image measurement program, it is responsible for imaging the object on the image sensor, telecentric lens and zoom lens are commonly used lenses in image measurement program. Whether to choose a telecentric lens or a zoom lens depends mainly on the specific measurement needs and application scenarios.

Telecentric Lens Mainly used to correct the parallax of conventional industrial lenses, they are able to maintain the consistency of the image magnification within a certain object distance, which does not change due to a change in the object distance, and therefore does not produce a situation where the nearer is bigger and the farther is smaller. This makes telecentric lenses very useful in measuring situations where the object to be measured is not on the same object plane. Telecentric lenses have excellent imaging qualities such as high telecentricity, no perspective error, and near-zero distortion, making them ideal for high-precision dimensional measurements and defect detection. For example, dual-side telecentric lenses combine the advantages of both object-side telecentric lenses and image-side telecentric lenses, which can complete the observation of large workpieces in one go, and are suitable for a wide range of scenarios, such as cell phone appearance size inspection, hardware measurement, glass container measurement, and automotive parts inspection.

Zoom Lenses on the other hand, it is an optical lens whose magnification can be continuously and infinitely adjusted within a certain range. Its focal length can be continuously changed, and the magnification of the lens can be changed without changing the object distance. This means that the shooter does not need to adjust the distance of the scene to be photographed to change the field of view and the size of the image. This characteristic of the zoom lens gives it a unique advantage in certain specific measurement scenarios, such as those that require wide-ranging adjustments to the field of view or the size of the object.

If the measurement task requires a very high degree of accuracy and stability, especially if the object to be measured is not on the same object plane, a telecentric lens may be a better choice. Whereas if the measurement task requires a wide range of field of view or target size adjustments and the accuracy requirements are not particularly high, then a zoom lens may be more appropriate.

Whether to choose a telecentric lens or a zoom lens in an image measurement program needs to be decided based on specific measurement needs and application scenarios. In the selection, the lens interface type, working distance, field of view, spectral characteristics, aberration rate and mechanical structure size and other factors should also be considered to ensure that the selected lens can meet the needs of the measurement program.