Reading device setting reading start position by reading reference hole having l-shape

A reading device comprising:

• a light transmissive member having a front surface on which an original is placed, and a back surface;
• a peripheral member located adjacent to the light transmissive member, the peripheral member including a back surface in which a first reference hole and a second reference hole are formed, the first reference hole including a first edge, the second reference hole including a second edge, wherein an extended line of the first edge and an extended line of the second edge intersect with each other at an angle to form an angled-shape;
• a reading sensor assembly located to face the back surface of the light transmissive member and the back surface of the peripheral member, the reading sensor assembly being configured to read an image while moving over a range including the light transmissive member and the peripheral member;
• and
• a controller configured to perform:
• controlling the reading sensor assembly to read a reading range including the reference hole to obtain a read image;
• determining a reference position based on the read image obtained in the controlling, the reference position being determined to an intersection between the extended line of the first edge and the extended line of the second edge;
• and
• setting a reading start position based on the reference position in the reading range, the reading start position being a position from which the reading sensor assembly starts moving when the reading sensor assembly reads the original.