Projection pattern forming method and scanner

The invention discloses a method for forming a projection pattern and a scanner, and the method comprises the steps: obtaining an original projection pattern which comprises a plurality of adjacent rectangular regions in a first direction, and defining two adjacent rectangular regions as a first rectangular region and a second rectangular region, the first rectangular area and the second rectangular area have a first common edge, the first rectangular area has a first display state, the second rectangular area has a second display state, and the first display state is different from the second display state; in the first rectangular area, defining and forming a first boundary area away from the second rectangular area from the first common edge in the first direction, and defining at least a part of area adjacent to the outside of the first boundary area in the first rectangular area as a non-boundary area; and setting the display state of the non-boundary area to include the first display state and the secon