一种集成图像处理功能的数字像元焦平面读出电路

A digital pixel focal plane readout circuit with integrated image processing function

摘要:

设计了一种像元级数字化焦平面读出电路，克服了传统模拟读出电路技术的电荷容量局限，实现了更大的动态范围和更低噪声的数字化图像读出；同时在像元内部进行数字化图像处理，可实现非均匀校正(NUC)、盲元补偿、数字时间延迟积分(TDI)、空间滤波等图像预处理功能。该电路采用40 nm CMOS工艺流片，面阵规格为640×512，像元步进为30 μm，全芯片尺寸约22 mm×19 mm。测试结果显示，该电路通过TDI、空间滤波功能可大幅降低(分别约90%和63%)输出图像空间噪声，提升成像质量。

Abstract:

A pixel-level digital focal plane readout circuit was designed to overcome the charge capacity limitations of traditional analog readout circuit technology, enabling a larger dynamic range and lower noise digital image readout. Additionally, digital image processing is performed internally at the pixel level, enabling functions such as Non-Uniformity Correction(NUC), dead pixel compensation, digital Time-Delay Integration(TDI), and spatial filtering for image preprocessing. The circuit was fabricated using a 40 nm CMOS process with an array specification of 640×512, a pixel pitch of 30 μm, and the overall chip size is approximately 22 mm×19 mm. Test results indicate that the circuit can significantly reduce(by approximately 90% and 63%, respectively) the spatial noise in the output image through TDI and spatial filtering functions, thereby enhancing the image quality.