We know that silicon is too shiny to absorb incoming light that's why anti-reflection coating is needed to make the incoming light stay inside the cell.
However, the problem is, even though the cell is covered with anti-reflection coating, the silicon material inside is still shiny and it still reflects the incoming light that passes through the anti-reflection coating so,
How come an anti-reflection coating be useful on a solar cell?
They explain that the coating has such a thickness that consecutive lights cancel each other that's why light waves do not go out, but canceling light waves mean that they were going out of the cell and they were canceled out. So lesser amount of light wave remains inside.
As they claim, how come light stays inside the cell?