Sensor having shield film covering main substrate for immunizing noise

A sensor comprising:

• a receptacle capable of being connected to an external plug;
• a second housing in which at least a part of the receptacle is accommodated;
• a main substrate on which an electronic component used for sensing is mounted;
• a shield film covering at least a part of the main substrate and shielding at least one of an electromagnetic wave emitted from the main substrate and an electromagnetic wave to penetrate the main substrate from an outside;
• a first housing in which at least a part of the main substrate and at least a part of the shield film are accommodated;
• a flexible connection member connecting the main substrate and the receptacle;
• and
• a protection member abutting on an end of the shield film from a side opposite to the main substrate, the end of the shield film facing the connection member.