Abstract: A spinning disk assembly including a support sheet having a window area, a center point and a slit region and also a disk having a center coupled to that center point of the support sheet, an outer circumference and a mid circumference. The mid circumference is located between the center and the outer circumference with the area between the center and said mid circumference defining a window viewing band which corresponds to the window area of the support sheet. The area between the mid circumference and the outer circumference defines a slit viewing band which corresponds to the slit region of the support sheet, so that when the center of the disk is coupled to the center point of the support sheet, part of the window viewing band is seen through the window of the support sheet and part of the slit viewing band is viewed through the slit region of the support sheet.