Olympus OM system close-up and macro equipment

Aperture Iris Diaphragm

Introduction

The Aperture Iris Diaphragm was designed for use with the Trans-Illuminator Base X-DE. It is shown in brochures and instruction manuals for the Olympus X and X-Tr stereo microscopes, and it is listed and illustrated as an optional accessory in some SZ-III stereo microscope brochures. It was still available as an accessory for microscopes for several years after the Olympus OM system was introduced in 1972, so it is surprising that it was not officially included in the OM macrophoto group.

It allows you to control the diameter of the beam of transmitted light, and it can also provide oblique illumination. The aperture iris has 17 blades and can be adjusted between 2 mm and 40 mm, and it can be offset by up to 5 mm.

Some of the microscope brochures describe it as fitting on or over the trans-illuminator base, but the only place where it can be attached is underneath the top plate of the base.

Aperture Iris Diaphragm

Turning the X-DE upside-down makes it easier to attach the iris apparatus.

Aperture Iris Diaphragm attached to X-DE base

Aperture Iris Diaphragm

The iris apparatus is attached to the under side of the top of the X-DE with four screws. The iris frame 55 protrudes above the top plate of the X-DE, and the iris positioning lever 54 passes through the small hole in the front of the top.

To attach the iris apparatus to the X-DE, carefully locate it with the iris positioning lever 54 passing through the small hole in the front of the top of the X-DE, and the iris frame 55 seated in the large hole in the top of the X-DE. Position the four screws above the four threaded holes, and tighten the screws.

If the iris apparatus is not seated properly, it can restrict adjustment of the mirror.

The three iris clamp screws 51 can be loosened so that the iris frame 55 can be rotated, to adjust the position of the aperture lever 53.

The aperture of the iris can be adjusted from 2 mm to 40 mm by using the aperture lever 53. For oblique illumination, pull and push the iris positioning lever 54; the maximum offset is 5 mm.

Versions

Only one version is known

Instructions

D-4 Iris Apparatus (Optional Accessory)

Aperture Iris Diaphragm

The iris apparatus is an accessory to control the beam of trans-illumination or to provide oblique illumination. It is set underneath the top of the sub-stage base. First set the slide rail and the iris sleeve at the appropriate position, insert the iris frame from below, then tighten the iris clamp screws 51. The iris may be opened or closed by horizontal movement of the aperture lever 53, producing an aperture adjustable from 2 mm to 40 mm in diameter. By pulling and pushing (not rotating) the iris positioning lever 54, desired oblique illumination can be obtained.

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Olympus OM system close-up and macro equipment