Diaphragm (optics) the lens. The centre of the diaphragm's aperture coincides with the optical axis of the lens system. Most modern cameras use a type of adjustable diaphragm known as an iris diaphragm, and often referred to simply as an iris. See the articles on aperture and f-number for the photographic effect and system of quantification of varying the opening in the diaphragm. A natural optical system that has a diaphragm and an aperture is the human eye. The iris is the diaphragm, and the opening in the iris of the eye (the pupil) is the aperture. An analogous dev in a
Diaphragm compressor properties and sufficient temperature resistance. A diaphragm compressor is the same as a membrane compressor. In the late 19th century William Burton started a workshop building pumps and air compressors at Nogent-sur-Oise, 60kM north of Paris, France. Henri Corblin, generally recognised as the inventor of the metallic diaphragm compressor, was based nearby in Paris itself and in 1923 he received a US patent for his invention and design work. The photograph included in this section depicts a three-stage diaphragm compressor used to compress hydrogen gas to 6,000 psi (41 MPa) for use in a prototype hydrogen and compressed natural gas