The donor materials based on ladder-type building blocks have been widely used in high-efficiency organic solar cells. The narrow absorption spectrum of corresponding polymer is the main reason that restricts the enhancement of photovoltaic performances. Recently, the Research Group for Organic Functional Materials designed a novel methylene-modified IDT building block (DMIDT), by introducing the sp²-hybridized bridged carbon atoms in the conjugated IDT main core. The polymer PDMIDT-TPD presents a broader and red-shifted absorption spectrum. After the preliminary optimization, a PCE of 8.26% is achieved by PDMIDT-TPD when blended with PC₇₁BM. This is the champion PCE result among the IDT-based polymer donors to the best of our knowledge. In the meantime, this polymer also presents good compatibility with non-fullerene acceptor. The corresponding research studies have been consecutively published on Macromolecules 2017, 50, 7984-7992. (SCI-Q1, IF = 5.835). The article was also selected as the most read article by the journal.