Time-series high-accuracy photometry is very important for research in stellar variability. For a long time photometry made by a photomultiplier was the only instrument for high precision stellar photometry. To overcome the atmospheric variation and instrumental problems, we must choose at least one stable star as a comparison star and move the telescope quickly between the targets. So the real efficiency is very low and one only can do it on photometric nights. To overcome this limitation, since 1989 we began to cooperate with the team of the STEPHI network. We used the Chevreton four-channel photometer which can observe the variable, two comparison stars and a chosen sky background simultaneously. The multi-channel photometer is much better than normal single channel photometer as we can see from the several STEPHI results. Now the very high quantum efficiency CCD becomes more and more popular, so we are trying to change to use CCDs. Here we give some general description of a large field high accuracy bright star CCD photometer being prepared for the Beijing Astronomical Observatory (BAO).