The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 29, 2018
Filed:
Dec. 12, 2014
Tianjin University, Tianjin, CN;
Suying Yao, Tianjin, CN;
Zhiyuan Gao, Tianjin, CN;
Jiangtao Xu, Tianjin, CN;
Zaifeng Shi, Tianjin, CN;
Jing Gao, Tianjin, CN;
Tianjin University, Tianjin, CN;
Abstract
The present invention relates to a CMOS image sensor. The present invention provides a digital pixel sensor capable of maintaining consistency between two reference voltage changing rates. To this end, the invention proposes a technical solution in which a digital pixel exposure method by using multiple ramp voltage as reference voltage is provided. Said method includes the following steps: by means of PWM pixel array, a PWM pixel is composed of a photodiode PD, a reset transistor MRST, a pixel or column level comparator, and a pixel or column or array level memory; the two input ends of the pixel level comparator are connected with PD node voltage and a predefined reference voltage V; after being reset, the PWM type digital pixel undergoes an exposure period; the exposure time includes a reset sampling period Tand an integration sampling period T; in resetting sampling period, reference voltage Vlinearly rises from Vto V; The integration sampling period is divided into several sub periods. The present invention mainly applies to design and manufacture of CMOS image sensors.