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 (birth control) White. Reflexions also manufactured a flat-spring diaphragm up until 2014. There are a number of variations. The SILCS diaphragm is made of silicone, has an arcing spring, and a finger cup is molded on one end for easy removal. The Duet disposable diaphragm is made of dipped polyurethane, pre-filled with BufferGel (BufferGel is currently in clinical trials as a spermicide and microbicide). Both the SILCS and Duet diaphragms are one-size-fits-all. Diaphragms usually come in different sizes and require a fitting appointment with a health care professional to determine which size a woman should wear. Single size diaphragms that do not