Scale pattern in a scale of an optical encoder includes a first scale mark that blocks a first light from being guided to an image capturer and guides a second light to the image capturer, and a second scale mark that guides the first light and the second light to the image capturer. Second scale mark is arranged in an ABS pattern and the first scale mark is arranged in an INC pattern by incorporating the second scale mark. Image capturer includes a first image capturing section that captures an image of the ABS pattern from the first light that arrives via the second scale mark, and a second image capturing section that captures an image of the INC pattern from the second light that arrives via the first scale mark and the second scale mark. Calculator calculates a position of a head relative to the scale.