Abstract: An acoustic sensing element has a substrate that includes a back chamber, a vibration electrode plate that is provided in a surface of the substrate while being opposite an upper surface opening of the back chamber, and a fixed electrode plate that is provided opposite the vibration electrode plate, an acoustic hole being made in the fixed electrode plate. The acoustic sensing element outputs an electric signal based on an electrostatic capacitance change generated between the vibration electrode plate and the fixed electrode plate by a displacement of the vibration electrode plate. A lower surface of the back chamber is closed into a pouched shape by the substrate.

Abstract: An acoustic sensing element has a substrate that includes a back chamber, a vibration electrode plate that is provided in a surface of the substrate while being opposite an upper surface opening of the back chamber, and a fixed electrode plate that is provided opposite the vibration electrode plate, an acoustic hole being made in the fixed electrode plate. The acoustic sensing element outputs an electric signal based on an electrostatic capacitance change generated between the vibration electrode plate and the fixed electrode plate by a displacement of the vibration electrode plate. A lower surface of the back chamber is closed into a pouched shape by the substrate.

Abstract: Provided is a microlens having an inorganic compound layer directly formed on the surface of a base lens material that is resistant to cracking and wrinkling of the inorganic compound layer under high-temperature and high-humidity environment and also to cracking of the base lens material by repeated temperature fluctuation, and an optical device using the microlens. A microlens, comprising a hardened product obtained by polymerization of a polymerizable composition containing a polymerizable monomer and metal oxide fine particles having an average diameter of 1 to 80 nm as essential components and an inorganic compound layer coated on the surface thereof. An optical device equipped with the microlens.