The technical advancements in the production of the microscopes has enabled scientists that study the cells to observe more and more complex features of the cell.
When the cell was first observed in the 17th century, the scientist studying it, Antoan vaan Lewenhuk could only see the shape and the outline of the cell.
With further advancements in the magnifying power and clarity of the microscopes scientists can now observe more than just the outline of the cell. They can observe the differences between different cell types, the miniature parts of the cells, organelles and even observe cell processes like meiosis in real time. Without the modern microscopy technology that would be impossible and our of the cell will be very limited.