An imaging portion of an imaging apparatus according to the present invention has a cover glass adhered by an adhesive to an imaging surface side of a CCD in a state of sandwiching leads (adhesion area B.sub.1), and has a slight airtight air gap formed on the imaging surface side of the CCD so as to render a circumference of the cover glass larger than the CCD. As for a circuit board, a concave portion for accommodating the CCD is formed, and a periphery of the cover glass is adhered to a top surface of the circuit board by the adhesive (adhesion area B.sub.2). Thus, the air gap is doubly sealed so that its airtightness is improved and influence of temperature change is reduced so as to prevent condensation on a back side of the cover glass and so on.