Single focus lens

Abstract

The single focus lens with the advantage of wide view field includes the first optical module with weak refraction index, the second optical module with positive refraction index, the third optical module with negative refraction index, the fourth optical module with positive refraction index, the fifth optical module with positive refraction index and one image sensing unit successively arranged from the object space to the image space. The single focus lens meets the following conditions: 0<f23 / f1<0.12; where f23 is the combination focus length of the second optical module and the third optical module and f1 is the focus length of the first optical module.

Description

technical field [0001] The invention relates to a single-focus lens, in particular to a single-focus lens applicable to a handheld camera. Background technique [0002] The miniaturization and the increase of the pixels of the image sensing unit make the requirements for the camera lens more and more stringent. At the same time, low-cost and wide-viewing-angle visual optical systems are increasingly used in products such as monitors, vehicle lenses, and interior mirrors. Japanese Laid-Open Patent Application No. Sho 61-035,414 discloses a wide viewing angle interior lens, which has four optical components and a crescent lens adjacent to the imaging end. [0003] However, although the internal viewing lens disclosed in Japanese Patent Application Laid-Open No. 61-035,414 can correct the distortion aberration, it cannot make all the light incident on the lens from the object end enter the CCD vertically, so shadows will be generated. [0004] Japanese Laid-Open Patent Public...

AI Technical Summary

Problems solved by technology

However, this design makes the entire optical system more complicated

[0005] Japanese Laid-Open Patent Publication No. 05-107,470 discloses an objective optical system, but it still cannot solve the problem of shadows

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