Optical lens assembly, image capturing apparatus and electronic device

Abstract

This invention provides an optical lens assembly comprising, in order from an object side to an image side: a first lens element with negative refractive power having an image-side surface being concave in a paraxial region thereof; a second lens element having positive refractive power; a third lens element having an object-side surface being concave in a paraxial region thereof; and a fourth lens element having an object-side surface being convex in a paraxial region thereof and an image-side surface being concave in a paraxial region thereof, the image-side surface thereof having at least one convex shape in an off-axis region thereof; wherein the optical lens assembly has a total of four lens elements. With such configuration, the optical lens assembly of the present disclosure is characterized by a reduced size and a wide field of view.

Description

RELATED APPLICATIONS[0001]This application claims priority to Taiwan Application Serial Number 105110720, filed on Apr. 6, 2016, which is incorporated by reference herein in its entirety.BACKGROUNDTechnical Field[0002]The present disclosure relates to an optical lens assembly and an image capturing apparatus, and more particularly, to an optical lens assembly and an image capturing apparatus applicable to electronic devices.Description of Related Art[0003]With the miniaturization and diversification of electronic devices, the photographing module has a wide range of applications including various intelligent electronic devices, driving cameras, security surveillance cameras, 3D depth sensing devices (e.g. Time-of-Flight (TOF) cameras), and Human-Computer interaction (HCI) platforms. Accordingly, the demand for photographing modules with high-spec lens assemblies is increasing. Moreover, there is a trend in the market towards lens assemblies featuring a wide field of view and a compa...

AI Technical Summary

Benefits of technology

The patent text discusses the configuration of an optical lens assembly that allows for a wide field of view with a compact size. The first lens element with negative refractive power allows for light to enter the lens assembly at a larger angle, while the second lens element with positive refractive power ensures the lens assembly has sufficient convergent capability. The third lens element corrects astigmatism with its concave object-side surface and the fourth lens element corrects field curvature with its concave and convex object-side surfaces. The optical lens assembly is also balanced to facilitate assembly and has a reduced interference between the first and second lens elements. It enhances its ability to correct off-axis aberration and increases manufacturing yield by controlling the back focal length. Additionally, it achieves a wide field of view by adjusting the aperture stop position.

Problems solved by technology

However, a conventional lens assembly with a wide field of view generally requires a large number of lens elements to receive light in order to capture an image of a larger area.

As a result, the size of the product equipped with the conventional lens assembly with a wide field of view cannot be reduced easily.

Accordingly, the conventional lens assembly with a wide field of view usually fails to concurrently meet the requirements of a wide field of view and a short total track length because of its configuration.

Or, it is likely that the overwhelming stray light renders the image quality unsatisfactory, limiting the range of applications of the conventional lens assembly with a wide field of view.

Therefore, the conventional design can no longer support the specification and fulfill the needs in the future.

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