Diaphragm (optics)

In optics, a diaphragm is a thin opaque structure with an opening (aperture) at its center. The role of the diaphragm is to stop the passage of light, except for the light passing through the aperture. Thus it is also called a stop (an aperture stop, if it limits the brightness of light reaching the focal plane, or a field stop or flare stop for other uses of diaphragms in lenses). The diaphragm is placed in the light path of a lens or objective, and the size of the aperture regulates the amount of light that passes through 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.

Iris diaphragms versus other types

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 photographic lens is called an iris diaphragm.

Iris (1987 film)

Iris is a 1987 Netherlands film directed by Mady Saks and starring Monique van de Ven.

Plot

A young woman, Iris, runs away to the big city on her eighteenth birthday. She moves in with an architect and decides to become a veterinarian. With an inheritance she buys an existing clinic in a backwoods town where Iris is leered at by the men, scorned by the women. Cruel jokes and gossip eventually lead to violence.A local thug breaks in her house while she is out. When she returns home late night, he attacks her, drag her to the wooden stairs, ties her hands, stretch her legs wide apart and ties to the railing of stairs and rapes her brutally.

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Iris (EP)

Iris is Miranda Sex Garden's second release, and first EP.

Track listing

Girl +

Girl + is an EP by punk blues band Boss Hog.

Track listing

All songs written by Boss Hog and produced by Cristina Martinez. The Japan version includes the Action Box EP.

Band members

Additional musicians

Girl (The Time song)

"Girl" was the final single released from The Time's debut album. Like most of the album, the song was recorded in Prince's home studio in April 1981, and was produced, arranged, composed and performed by Prince with Morris Day later adding his lead vocals. The single reached number 49 on the U.S. R&B singles chart.

The tender ballad is built around the piano and synthesizers and features live drumming and bass. The emotional lyrics delivered by Day tell of a difficult breakup and that he is still in love with the song's subject. Prince's backing vocals are unmistakable, especially in the chorus.

The U.S. 7" single was backed with an edit of album track, "The Stick", a funky number which was written by Revolution member Lisa Coleman (uncredited), who also provided background vocals. Another uncredited Revolution member was Doctor Fink, who provided synthesizer solos for the track. A 12" single was not released.

Though not one of their biggest hits, "Girl" is often played in concert and a live version of the song recorded at the House of Blues in 1998 and was included on Morris Day's 2004 album, It's About Time.

Girl (1994 film)

Girl is a 1994 Australian film about four teenagers who enter a magazine photo competition.

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