Iris Diaphragm

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iris diaphragm

[′ī·rəs ′dī·ə‚fram]

Iris Diaphragm


a type of stop that is often used in photographic lenses and other instruments to adjust the brightness of the image and to vary the depth of field. It consists of thin, opaque, crescent-shaped vanes that overlap one another, thus forming an approximately circular opening. By moving the stop ring on the lens or a lever connected to it, all the vanes are turned simultaneously, so that the objective’s opening (aperture ratio) is varied smoothly.

References in periodicals archive ?
The flexibility of the Iris Diaphragm and muscle valves shows that valve end users may benefit by looking beyond the obvious equipment.
These new exhibits will be supported by examples of their Kek Universal mills, Kek kibblers, traditional Mucon iris diaphragm and disc valves and Bridge Breaker silo discharge aids.
For food industry contractors and end-user companies alike, the company manufactures a variety of ancillary equipment which includes Mucon iris diaphragm valves, disc valves, Rotalog level indicators and Bridge Breaker discharge aids.