Symmetric wide-angle pinhole lens

Abstract

The invention discloses a symmetric wide-angle pinhole lens. The lens comprises a first group of high-temperature-resistant glass flat plates L1, a second group of large-view-field positive lenses L2and L3, a third group of positive lenses L4, and a fourth group of positive lenses L5 and L6; and light emitted by an aperture diaphragm K0 sequentially passes through the first group of the high-temperature-resistant glass flat plates L1, the second group of the large-view-field positive lenses L2 and L3, the third group of the positive lenses L4, and the fourth group of the positive lenses L5 and L6 to be imaged on an imaging surface P7. The symmetric wide-angle lens disclosed by the invention can meet the imaging requirements in a high-temperature environment, remarkably solves the shadow and distortion problems of imaging, and has the beneficial effects of being small in size, compact in structure, free of aspheric surface design, low in cost and high in imaging quality.

Description

technical field [0001] The invention relates to a symmetrical wide-angle lens, in particular to a pinhole-type wide-angle lens for a furnace endoscope in a high-temperature-resistant environment. It can also be widely used in pinhole camera (monitoring) equipment. Background technique [0002] The wide-angle lens is the core component of the high-temperature furnace monitoring equipment: the scene in the furnace can be imaged on the CCD or other devices in real time through the lens, and then output to the user's display device. [0003] At present, the existing lenses used in high-temperature furnace monitoring equipment on the market are wide-angle, but have obvious defects: [0004] 1. The output image of the existing lens is severely distorted; [0005] 2. The shadow around the image is obvious; [0006] 3. The asymmetric structure design is adopted, and the processing and installation cost is too high. Contents of the invention [0007] To solve the above problems...

AI Technical Summary

Problems solved by technology

[0004] 1. The output image of the existing lens is seriously distorted;

[0005] 2. The shadow around the image is obvious;

[0006] 3. Adopt asymmetric structure design, the cost of processing and installation is too high

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