A more difficult problem to solve is the matching of the number and the size of the pixels of SLM and the CCD; the ideal situation would be that the number and the size of SLM pixels are the same as CCD pixels, but CCD pixel size is getting
smaller and smaller (4–5 μm), whereas the SLM pixel size is limited to around 10 μm due to the constraints of the LCD, thereby leading to a mismatch between the two.