What are telecentric lenses?
Telecentric lens are specially design to adjust the parallax in the ordinary lens. Parallax means when the object’s distance changes, its magnification also does. Telecentric lenses are specialised lenses helpful in machine vision and imaging systems to boost performance and provide a highly accurate reading. A leading telecentric lens firm in India can provide standard parts, pre-engineered requirements, and totally custom lenses.
Functionality of telecentric lens:
- Telecentric lenses help create images that are independent of the distance between an object and the observer. When compared to ordinary lenses, telecentric lenses minimize the perspective error. That causes closer things to look larger than those farther away from the lens, boosting measurement accuracy.
- Digital image sensors, machine vision systems, metrology equipment, and microlithographic camera systems are all applications of telecentric optics.
Choose the lens from a good telecentric lens manufacturing company which provides variety of preliminary designs based on what best suits your needs.
Basic three types of telecentric Lenses:
Telecentric lenses are useful for image and projection systems to improve measurement precision. Object space and image space are two kinds of telecentricity.
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Object space telecentric lens
The entrance pupil of an object space telecentric lens is infinity. In object space, all primary rays are parallel to the optical axis. When a machine vision system uses an object-space telecentric lens, the picture magnification is independent of the object’s distance and position inside the field of view.
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Image space telecentric lens
An image space telecentric lens’ exit pupil is infinity. In picture space, the primary ray is parallel to the optical axis. These lenses can be employed in dimensioning systems to ensure that measurement accuracy is independent of the distance between the image sensor and the field of view.
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Bi-telecentric lens
Both pupils of a double telecentric or bi-telecentric lens are at infinity. The principal rays of this type of lens are parallel to the optical axis in both object and picture space. Magnification in both image and object space is independent of distance or position in the field of view with bi-telecentric lenses.
When are telecentric lens used?
- Conventional lenses perceive an object as larger when it is close and smaller when it is far, according to everyday experience. The difference can be crucial when measuring objects to within a few thousandth of an inch. Good telecentric lens can solve this problem. Magnification depth of field refers to how far an object’s distance can alter while still appearing to be the same size.
- Telecentric lenses are useful for a wide range of dimensional-gauging applications due to their large magnification depth of field. Threaded fasteners, machined parts, bottle geometry, are all common instances, as are any time you need to measure something with minimal or no perspective error, or at different distances.
- Sometimes all you want is for your camera to see everything in its field of view from the same perspective. A conventional lens would only be able to see clearly till a specific point. A telecentric lens, on the other hand, makes the job very simple.
How to choose the right telecentric lens?
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Requirement of more lens elements
Systems designers must be aware of the various types of telecentric lenses and their applications when selecting them. Doubly telecentric lens can have a lot of lens elements in their design. These lens systems are useful for precision measuring applications.
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Less lens elements and reduced costs
Many telecentric lens manufacturers and suppliers in India offer object-side telecentric lens systems, which are just telecentric on the object side, to reduce the cost of these lens systems. The focal length of the lens on the image side appears as it would in an ordinary camera. Furthermore, the design of camera is such that fewer lens elements are needed.
At a reputed telecentric lens company, customers can choose from a variety of preliminary designs based on what best suits their needs with the pre-engineered lenses.
Any advanced telecentric lens manufacturing company can quickly and economically provide high-performance telecentric lenses for a variety of applications, such as machine vision, inspection, metrology, image sensor tests, and projection systems with good price-to-performance ratio.
I hope you like this article on telecentric lenses, in future I also try to write some informational articles.
