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Knight Optical’s iris diaphragms offer dynamic control of beam width and light throughput in optical systems. These sprung steel leaf diaphragms are available in fully closing and part closing types with open apertures up to 300mm. Each aperture is supplied in a high quality blackened brass body to absorb unwanted light and reduce the impact of reflection on the rest of the system.

Stainless steel leafed iris diaphragms are supplied with high quality stainless steel leaves for improved lifespan and accuracy.

These iris diaphragms are perfect for manual control of the input beam. For fixed aperture sizes we recommend Knight Optical's range of high precision pinhole and slit apertures that offer improved repeatability and accuracy.

Knight Optical also offers an extensive custom optic service thanks to our many years of experience in the industry. Our apertures can be manufactured to any size or shape to suit your application. More information is available by contacting our technical sales team directly.

Max. aperture tol.
Min. aperture tol. (may be smaller)
Outer diameter tol.
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(zero min aperture thk +/-0.15mm)
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Smaller and larger size iris diaphragms available.
Mounting options available.

8 Items

Name Maximum Aperture (mm) Minimum Aperture (mm) Outer Diameter (mm) Thickness (mm) Number of Leaves Pin Length (mm) Price Buy
GIS7050 50 2.8 70 7.5 16 15
GIS5337 37 1.9 53 6 16 12.5
GIS5036 36 1.9 50 6 16 12.5
GIS3725 25 1.4 37 5.5 14 12.9
GIS3020 20 1.2 30 5.5 12 13.2
GIS2415 15 1.2 24 5 12 11.3
GIS2012 12 1 19.8 5 10 11.5
GIS1508 8 0.8 14.8 4.5 8 7

8 Items


Stainless Steel Leaves

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