Black level control for image sensors

摘要

An embodiment image sensor includes a pixel region spaced apart from a black level control (BLC) region by a buffer region. In an embodiment, a light shield is disposed over the BLC region and extends into the buffer region. In an embodiment, the buffer region includes an array of dummy pixels. Such embodiments effectively reduce light cross talk at the edge of the BLC region, which permits more accurate black level calibration. Thus, the image sensor is capable of producing higher quality images.

主权项

1. An image sensor, comprising:
a pixel region spaced apart from a black level control (BLC) region by a buffer region, the buffer region including an array of dummy pixels, wherein the buffer region is a microlens-free region; a metal grid over the pixel region and at least one dummy pixel, wherein the metal grid extends along opposing sides of the at least one dummy pixel in a plan view; and a light shield disposed over the BLC region and extending into the buffer region.