An exposure apparatus for sequentially exposing an energy beam on a plurality of divided areas placed in the shape of a matrix on an object, and forming a pattern on each of the plurality of divided areas, the apparatus comprising: a movable body (WST1, WST2) for holding the object and arranged to move parallel to a predetermined plane; a position measurement system (70, 71) which has a plurality of heads (60, 60 2, 60 3, 60 4) provided on the movable body, and is arranged to obtain a positional information of the movable body, based on measurement results of a predetermined number of heads configured to irradiate a measurement beam on a measurement plane (21, 22) that has an opening partially and is placed facing the movable body and roughly parallel to the predetermined plane, to receive a return beam from the measurement plane, and to measure a position of the movable body in each measurement direction, the predetermined number of heads being of the plurality of heads; and a control system arranged to drive the movable body based on the positional information obtained by the position measurement system, wherein of the plurality of heads, a separation distance (A, B) of two heads set apart in a predetermined direction within the predetermined plane is larger than a size (a i, b i) of the opening in the predetermined direction, and wherein: on the measurement plane, a two-dimensional grating whose periodic directions are in two axial directions that are orthogonal to each other within the predetermined plane is formed, and at least one of the two axial directions serves as a measurement direction for each of the plurality of heads, characterized in that: the separation distance of the two heads set apart in the predetermined direction being larger than a sum of the size of the opening in the predetermined direction and a size (W, L) of one of the plurality of divided areas in the predetermined direction, and that the control system is arranged to switch at least one of the predetermined number of heads used to compute the positional information of the movable body to a different head according to a position of the movable body. a movable body (WST1, WST2) for holding the object and arranged to move parallel to a predetermined plane; a position measurement system (70, 71) which has a plurality of heads (60, 60 2, 60 3, 60 4) provided on the movable body, and is arranged to obtain a positional information of the movable body, based on measurement results of a predetermined number of heads configured to irradiate a measurement beam on a measurement plane (21, 22) that has an opening partially and is placed facing the movable body and roughly parallel to the predetermined plane, to receive a return beam from the measurement plane, and to measure a position of the movable body in each measurement direction, the predetermined number of heads being of the plurality of heads; and a control system arranged to drive the movable body based on the positional information obtained by the position measurement system, wherein of the plurality of heads, a separation distance (A, B) of two heads set apart in a predetermined direction within the predetermined plane is larger than a size (a i, b i) of the opening in the predetermined direction, and wherein: on the measurement plane, a two-dimensional grating whose periodic directions are in two axial directions that are orthogonal to each other within the predetermined plane is formed, and at least one of the two axial directions serves as a measurement direction for each of the plurality of heads the separation distance of the two heads set apart in the predetermined direction being larger than a sum of the size of the opening in the predetermined direction and a size (W, L) of one of the plurality of divided areas in the predetermined direction, and that the control system is arranged to switch at least one of the predetermined number of heads used to compute the positional information of the movable body to a different head according to a position of the movable body.