How to design a telecentric lens

The design purpose of a telecentric lens is to eliminate variations in magnification due to inconsistent distances between the measured object (or CCD chip) and the lens. This ensures uniform magnification regardless of distance. The design principles and applications of telecentric lenses can be understood through three classifications:

1. Object-Side Telecentric Design Principle and Purpose

In this design, the principal rays from the object side are parallel to the optical axis, with the point of convergence at infinity on the image side. This is called an "object-side telecentric optical path." Its purpose is to eliminate reading errors caused by inaccurate focusing on the object side.

2. Image-Side Telecentric Design Principle and Purpose

Here, the principal rays from the image side are parallel to the optical axis, with the point of convergence at infinity on the object side. This is termed an "image-side telecentric optical path." Its purpose is to eliminate measurement errors introduced by inaccurate focusing on the image side.

3. Dual-Side Telecentric Design Principle and Purpose

This design combines the benefits of object-side and image-side telecentricity, offering a dual effect. It is primarily used in visual measurement and inspection fields.

Telecentric lenses by FALenses Technology make full use of optical imaging characteristics, designed with high precision to consider light's effect during imaging. These lenses are widely used in machine vision for precision measurement and high-accuracy inspection. The dual telecentric design minimizes errors and provides consistent magnification across varying distances, crucial in fields where precise measurement is essential.