Light receiving element, and rotation detector

A light receiving element comprising:

• a plurality of first absolute light receivers that are arranged on a first circumference having a first radius and output a detection signal according to an absolute method;
• and
• a plurality of light receiver groups that output a detection signal according to an increment method, wherein:
• the plurality of light receiver groups are selectively arranged in a region having a radius greater than the first circumference, and are arranged on a second circumference concentric with the first circumference and having a second radius greater than the first radius,
• the plurality of first absolute light receivers do not overlap with the plurality of light receiver groups,
• the plurality of light receiver groups are arranged at a predetermined arrangement pitch in an arrangement direction along the second circumference,
• each of the plurality of light receiver groups includes a first light receiver and a second light receiver arranged at a position shifted by ¼ of the predetermined arrangement pitch in the arrangement direction with respect to the first light receiver,
• the first light receiver includes a first main phase portion and a first sub phase portion shifted in the predetermined arrangement direction by 1/12 of the predetermined arrangement pitch with respect to the first main phase portion,
• the first main phase portion includes a first main body portion and a first main separation portion arranged to be spaced apart from each other in the vertical direction,
• a width of the first main separation portion in the arrangement direction is less than ¼ of the predetermined arrangement pitch,
• the first main phase portion, as a whole, has a width of ⅓ of the predetermined arrangement pitch in the arrangement direction,
• the first sub phase portion includes a first sub body portion and a first sub separation portion arranged to be spaced apart from each other in the vertical direction,
• a width of the first sub separation portion in the arrangement direction is less than ¼ of the predetermined arrangement pitch,
• the first sub phase portion, as a whole, has a width of ⅓ of the predetermined arrangement pitch in the arrangement direction,
• the first sub separation portion is adjacent to the first main body portion,
• the first main separation portion is adjacent to the first sub body portion,
• the second light receiver includes a second main phase portion and a second sub phase portion shifted in the arrangement direction by 1/12 of the predetermined arrangement pitch with respect to the second main phase portion,
• the second main phase portion includes a second main body portion and a second main separation portion arranged to be spaced apart from each other in the vertical direction,
• a width of the second main separation portion in the arrangement direction is less than ¼ of the predetermined arrangement pitch,
• the second main phase portion, as a whole, has a width of ⅓ of the predetermined arrangement pitch in the arrangement direction,
• the second sub phase portion includes a second sub body portion and a second sub separation portion arranged to be spaced apart from each other in the vertical direction,
• a width of the second sub separation portion in the arrangement direction is less than ¼ of the predetermined arrangement pitch,
• the second sub phase portion, as a whole, has a width of ⅓ of the predetermined arrangement pitch in the arrangement direction,
• the second sub separation portion is adjacent to the second main body portion,
• the second main separation portion is adjacent to the second sub body portion,
• the first main body portion and the second main body portion are arranged in the arrangement direction, and a gap between the first main body portion and the second main body portion is less than ¼ of the predetermined arrangement pitch, and
• the first main separation portion and the second main separation portion are arranged in the arrangement direction, and a gap between the first main separation portion and the second main separation portion is less than ¼ of the predetermined arrangement pitch.