Display device and detection device

A display device comprising:

• a first substrate;
• a second substrate opposed to the first substrate;
• a display functional layer arranged between the first substrate and the second substrate to display an image in a display region;
• a first electrode layer that is arranged in the display region of the second substrate and includes a plurality of first electrodes for detecting contact or proximity of an external object;
• a second electrode arranged between the first substrate and the second substrate to be opposed to the first electrodes;
• a plurality of third electrodes that are arranged between the first substrate and the second substrate and receive a pixel signal;
• and
• an insulating layer covering the first electrode layer, wherein
• in the insulating layer, a relative dielectric constant of a portion superimposed on the first electrodes is different from a relative dielectric constant of a portion not superimposed on the first electrodes at least in the display region,
• the insulating layer including a first insulating layer having a first relative dielectric constant and a second insulating layer having a second relative dielectric constant larger than the first relative dielectric constant,
• contact or proximity of the external object is detected based on a change in capacitance generated between the first electrodes and the second electrode, and
• in the insulating layer, the first insulating layer is arranged at a portion superimposed on the first electrodes and the second insulating layer is arranged at a portion not superimposed on the first electrodes,
• a distance from an upper surface of the first insulating layer to an upper surface of the second substrate is substantially constant and substantially the same as a distance from an upper surface of the second insulating layer to the upper surface of the second substrate.