Slits, pinholes and iris diaphragms are useful in providing a defined or reduced physical aperture to allow only a specific amount of light through a system. The slits and pinholes are small enough that they will act as quasi-diffraction sources or spatial filters for a number of applications.

The pinhole apertures are precision etched in either stainless steel or copper foil. The copper foil version allows for higher power levels, as the copper is able to dissipate heat more effectively than the stainless steel versions. The mounted pinholes are mounted in a 16mm diameter metal disc marked with the pinhole diameter. These are stronger and fit directly into our pinhole mounts.

Diaphragms are made from a series of interlocking leaves which open and close in such a way that a quasi-circular aperture is formed. Diaphragms are extremely useful in empirically determining the need for aperture stops to reduce scatter and stray light. These iris diaphragms are made from tempered steel leaves mounted in a metal ring. They are fitted with an actuating lever. Each iris has a smooth and continuous operating range. The dual blade iris diaphragms can be closed down to zero aperture. These irises have a plain outer casing that is normally mounted in a housing with a slight push fit.

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Aperture Diameter

Pinhole Diameter

Slit Width



Precision Air Slit 10mm Slit Width

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Precision Air Slit 100mm Slit Width

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Precision Air Slit 150mm Slit Width

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Precision Air Slit 200mm Slit Width

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Precision Air Slit 25mm Slit Width

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Precision Air Slit 5mm Slit Width

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Precision Air Slit 50mm Slit Width

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Iris Diaphragm with 8mm Maximum Aperture

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Iris Diaphragm with 12mm Maximum Aperture

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Iris Diaphragm with 15mm Maximum Aperture

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Iris Diaphragm with 22mm Maximum Aperture

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Iris Diaphragm with 36mm Maximum Aperture

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