Convex lens focus detection device

Abstract

The invention belongs to the field of optical detection, and particularly relates to a convex lens focal length detecting device. The convex lens focal length detecting device is used for judging whether the actual focal length of a convex lens to be detected is within the standard focal length range of a standard convex lens or not. The convex lens focal length detecting device comprises a light-emitting component which can emit infrared rays, a detecting box which can fix the convex lens, and an image collection module which can collect and display an image formed by the infrared rays. The image collection module and the light-emitting component are placed on the two sides of the convex lens respectively, the light-emitting component is fixed inside the detecting box and is placed at the optical center of the standard convex lens on the detecting box, the image collection module is used for detecting the image formed by the way that the light-emitting component penetrates through the convex lens to be detected, and therefore whether the focal length of the convex lens to be detected is within the standard focal length range or not can be judged. Operation is simple, convenient and fast, complex adjusting is avoided when the convex lens is assembled on an infrared detector, and the assembling efficiency of the infrared detector is greatly improved.

Description

technical field [0001] The invention belongs to the field of optical detection, in particular to a focal length detection device of a convex lens. Background technique [0002] The light emitted by the infrared emission tube in the active infrared detector is scattered light. In order to make the emitted light radiate farther, the scattered light needs to be turned into a parallel beam. [0003] At present, the scattered light is usually focused into a parallel beam by using an optical convex lens, and the infrared emitting tube is placed on the focal plane (focus position) of the convex lens so that the scattered light emitted by the infrared emitting tube passes through the convex lens and is focused into a parallel beam. In actual production, the size of the convex lens is deviated after injection molding, resulting in different focal lengths of the convex lens. In this way, when assembling active external detector products, it is necessary to carry out focusing work in ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the defects of the prior art, and provide a convex lens focal length detection device, aiming at solving the problem that the convex lens in the prior art has dimension deviation after injection molding, and when it is assembled into an active infrared detector, a special assembly environment is required. Complex operation and low assembly efficiency

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