CMOS imaging array with improved noise characteristics

An image sensor comprising:

• a two-dimensional array of CMOS pixel cells organized as a plurality of rows and columns, said pixel sensors in each column being connected to a corresponding bit bus, and each of said pixel sensors in each row being connected to a corresponding row select line, each pixel cell comprising:
• a photodiode;
• a floating diffusion node;
• a transfer gate that couples said photodiode to said floating diffusion node in response to a first gate signal;
• a shielding electrode that shields said floating diffusion node from said first gate signal, said shielding electrode being held at a constant potential while said transfer gate couples sais photodiode to said floating diffusion node;
• and
• an output stage that generates an output signal related to a charge on said floating diffusion node and couples that output signal to said corresponding bit bus in response to a row select signal on said row select line corresponding to that pixel cell;
• and
• a row decoder that generates said row select signal on a selected one of said row select lines in response to a row address being coupled thereto.