The reflector (110) can be a fixed orifice plate or an adjustable aperture.

The static orifice (22) is located downstream of the valve closing body (11) in order to prevent cavitation.

The diaphragm is fixed relative to the image plane.

A magnet (52) is secured to the diaphragm switching module (54) is secured within one of the chamber at a position spaced from the diaphragm.

The reflector (110) can be a fixed orifice plate or an adjustable aperture.

The layer is deposited via a number small of openings in the back-plate, the diaphragm and/or between the diaphragm and the back-plate.

The diaphragm chamber is formed between a fixed wall and a flexible diaphragm, which can be deflected and expanded from its neutral position into a diaphragm housing.

A vibration diaphragm (8) is mounted between the first fixed plate (1) and the second fixed plate (2).

A DC voltage is applied between the diaphragm and a fixed electrode to cause the diaphragm to deflect to simulate an effective pressure.

The vibrating diaphragm covers the top of the main body, and the peripheral part of the vibrating diaphragm connects with the main body fixedly.

The capacitive transducer structure (100) comprises a conductive movable diaphragm (106), a fixed counter electrode (107), and a predetermined air gap (109) between said diaphragm (106) and electrode (107).

The static distance between the diaphragm and the back-plate of the microphone is smaller than 10 νm.

The activator (13) includes a pin (14) that is fixedly positioned to the diaphragm.

The rubber frame (10) fixedly presses the optical diaphragm (40), so as to fix the optical plate (30) and the optical diaphragm (40).

The static orifice (22) is located downstream of the valve closing body (11) in order to prevent cavitation.