Diaphragm (optics) bright spots, for example night cityscapes. Some cameras, such as the Olympus XA or lenses such as the MC Zenitar-ME1, however, use a two-bladed diaphragm with right-angle blades creating a square aperture. Similarly, out-of-focus points of light (circles of confusion) appear as polygons with the same number of sides as the aperture has blades. If the blurred light is circular, then it can be inferred that the aperture is either round or the image was shot "wide-open" (with the blades recessed into the sides of the lens, allowing the interior edge of the lens barrel to effectively become the iris).
Diaphragm (birth control) IUD and the combined oral contraceptive pill. In 1965, only 10% of U.S. married couples used a diaphragm for contraception. That number has continued to fall, and in 2002 only 0.2% of American women were using a diaphragm as their primary method of contraception. In 2014 Janssen Pharmaceuticals announced the discontinuation of the Ortho-All Flex Diaphragm, making it very difficult for women in the US to have that option as a birth-control method. The single-sized, silicone diaphragm was developed by PATH during the late 2000s. It was licensed to Kessel Marketing & Vertriebs GmbH of Frankfurt, Germany which began to