Reading device

A reading device comprising:

• an antenna element;
• a substrate including a communication circuit configured to perform transmission and reception of radio signals with an RFID tag via the antenna element, and a ground plane configured to provide a reference potential of the antenna element;
• a connecting member protruding from the substrate in a thickness direction of the substrate and configured to electrically connect the communication circuit and the antenna element;
• and
• a casing configured to retain the antenna element, the substrate, and the connecting member, the casing having a plate-like outer shape whose dimension in the thickness direction is smaller than dimensions in a height direction and a width direction when viewed in the thickness direction,
• wherein the antenna element is arranged separately from the substrate toward one side in the thickness direction,
• wherein the casing includes a first surface portion that covers the substrate when viewed from the other side in the thickness direction, and
• wherein in a case where a distance in the thickness direction from a feed point at which the connecting member comes into contact with the antenna element to the ground plane is a first distance, and a distance in the thickness direction between the substrate and the first surface portion is a second distance, the first distance is greater than the second distance,
• wherein the casing includes a second surface portion that covers the substrate when viewed from the one side in the thickness direction, and
• wherein the antenna element is supported either (i) on a surface of the second surface portion at an inner side of the casing, or (ii) on a surface of the second surface portion at an outer side of the casing.