Telecentric lens is a type of optical lens, also known as television lens, or a telephoto lens. Through special lens design, its focal length is relatively long, and the physical length of the lens is usually smaller than the focal length. The characteristic is that it can represent distant objects larger than their actual size, so it can capture distant scenery or objects more clearly and in detail.
Telecentric lenses are widely used in scenes such as sports events, wildlife and nature photography, and astronomical observations, because these scenes often require shooting or observing objects from a long distance. Telecentric lenses can bring distant objects “closer” while maintaining the clarity and detail of the picture.
In addition, due to the long focal length of telecentric lenses, they can achieve background blur and shallow depth of field, making the subject more prominent when shooting, so they are also widely used in portrait photography.
The telecentric lens
The working principle of a telecentric lens is to use its special structure to disperse light evenly and project the image onto a sensor or film. This feature allows it to achieve better imaging results when shooting scenes far away from the subject. So, what are the characteristics of telecentric lenses?
The edge imaging of the telecentric lens will not bend. Even at the edge of the lens, the lines still maintain the same intersection angle with the central axis of the lens, so high-precision images can be taken.
Because of the orthogonal projection, the telecentric lens can maintain the proportional relationship of space, making the captured images have a strong three-dimensional sense.
Due to the special internal optical structure, the telecentric lens can keep the light entering the lens parallel at all positions, which means that the image lines captured by the lens will remain straight without bending or deformation.
Telecentric lenses are widely used in the following fields:
In fields such as computer vision that require image processing, telecentric lenses are widely used because of their high-precision imaging effects, which make image processing more precise.
Telecentric lenses are often used in some industrial inspections that require high-precision imaging.
In some professional photography, telecentric lenses are often used, such as architectural photography, product photography, etc.
In aircraft photography and telephoto photography, telecentric lenses can capture images with strong three-dimensionality and high precision, and are widely used.
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