Bi-telecentric prime lens

Abstract

The invention discloses a double-telecentricity fixed-focus lens. A first single positive spherical lens, a second single positive spherical lens, a third single negative spherical lens, a fourth single negative spherical lens, a fifth single negative spherical lens, a sixth single positive spherical lens and a seventh single positive spherical lens are successively arranged from an end of a tested object; the second single positive spherical lens and the third single negative spherical lens are combined into a bonding lens; the fifth single negative spherical lens and the sixth single positive spherical lens are combined into a bonding lens; and a diaphragm is positioned between the third single negative spherical lens and the fourth single negative spherical lens. The double-telecentricity fixed-focus lens reduces quantity of the lenses, lowers the manufacture cost, and enables the structure to be simple, smaller in volume and lighter in weight on the premise that the lenses are few, Meanwhile, the double-telecentricity fixed-focus lens is small in total length of the lens, big in an F value and big in a maximum imaging surface.

Description

technical field [0001] The invention relates to an industrial lens for precision industrial detection, in particular to a telecentric fixed-focus lens. Background technique [0002] With the wide application of machine vision systems in the field of precision inspection, ordinary industrial lenses have been difficult to meet the inspection requirements. This is due to the following restrictive factors in ordinary optical lenses, 1. Errors caused by image deformation and viewing angle selection; 2. Inappropriate The uncertainty of the boundary caused by the interference of the light source will affect the accuracy of the measurement. [0003] In order to make up for the shortcomings of ordinary lenses and meet the needs of precision inspection, telecentric lenses came into being. Based on its unique optical characteristics: high resolution, ultra-wide depth of field, ultra-low distortion, and unique parallel light design, the telecentric lens can enlarge the image within a c...

AI Technical Summary

Problems solved by technology

[0004] However, telecentric lenses currently on the market are generally heavy in weight, large in size, and high in production costs, which makes it difficult for telecentric lenses to be popularized in industrial inspections.

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