Kern OKO 178 Metallurgical Microscope, Trinocular, 5x to 50x, Reflected and Transmitted Light

Metals and surfaces are examined under reflected light, whilst transparent specimens are examined under transmitted light. The Kern OKO 178 combines both in a single instrument: LED reflected light and LED transmitted light of 5 watts each, separately dimmable, plus infinity optics, Köhler illumination and a simple polarisation unit, all included as standard. Kern describes the microscope as professional and versatile, designed for the inspection of metals and surface analysis.

Objectives with space for a fifth

The standard objectives are 5x, 10x, 20x and 50x, all of Infinity Semi-Apochromatic quality. The revolver has five positions, one of which remains free. With the HWF-10x eyepieces (22 mm field of view, anti-fungus, high eye point), this gives a magnification range of 50x to 500x. For the free position, Kern offers as accessories a 100x oil immersion objective with an aperture of 1.25 (OBB-A1241), an 80x objective with a long working distance and an aperture of 0.8 (OBB-A1530), as well as other semi-apochromatic objectives. Kern classes the 80x objective as an objective with a long working distance.

Reflected light, transmitted light and polarisation

Both reflected light and transmitted light illumination have a power of 5 watts each. The Abbe condenser with an aperture of 1.25 is centring and height-adjustable; it also features an aperture diaphragm and a field diaphragm for full Köhler illumination. The simple polarisation unit, comprising an analyser and a polariser, is part of the standard equipment. A blue filter is included as standard; accessories available include a polariser for transmitted light illumination, as well as yellow, green and grey filters.

Head and stage

The Siedentopf tube is trinocular, inclined at 30 degrees and rotatable. The interpupillary distance can be adjusted between 50 and 75 mm, and dioptre adjustment is available on both sides. The open mechanical stage has a travel range of 77 x 52 mm. An object holder for two slides and an extension plate for the stage are available as accessories. The coaxial coarse and fine adjustment mechanisms operate in increments of 0.002 mm. The microscope measures 472 x 211 x 440 mm (W x D x H), has a net weight of 11 kg and is powered by a mains adaptor (100 to 240 V, 50/60 Hz, 0.3 A, protection class III).

Documentation with a camera

The third tube port carries a camera. Kern offers C-mount adaptors with 0.5x (adjustable focus) and 0.75x magnification, as well as an adaptor for trinocular models, and the ODC 825, 832, 841 and 854 microscope cameras and the ODC 241 tablet camera.

OKO 178 or a biology microscope

The OBN 135 is intended for brightfield transmitted light on specimens; the OBN 141 is intended for use with fluorescence. The OKO 178 is the choice when reflected light is needed, for example when examining metals and surfaces.

Typical applications

Kern describes the OKO 178 as being suitable for the inspection of metals and for surface analysis. As a combination of LED reflected light and LED transmitted light, it covers both opaque and transparent samples.

• Inspection of metals
• Surface analysis using reflected light
• Transmitted light examinations
• Polarisation observations using the supplied unit

Regulatory information

As an electrical device, the microscope falls under the ElektroG. The manufacturer Kern & Sohn GmbH is registered under the WEEE registration number DE 80821200. How to return old appliances is described on the page Environment and disposal.

Frequently Asked Questions

What is the magnification of the OKO 178? The objectives provide magnifications of 5x, 10x, 20x and 50x. With the 10x eyepieces, this gives a total magnification of 50x to 500x.

Is a polarisation unit included? Yes, a basic unit comprising an analyser and a polariser is included in the scope of delivery.

Can I add a 100x oil objective? Yes, Kern offers a 100x objective (oil, 1.25 aperture) as an accessory. There is a free position on the revolver.

Can the reflected and transmitted light be controlled separately? Yes, both 5 W LED light sources can be dimmed independently of one another.

How long is the warranty? According to Kern & Sohn, this device comes with a 3-year warranty. Kern grants 3 years on products with a list price of €500 or more and 2 years on products below that and on components; wear parts such as batteries and rechargeable batteries are excluded. Warranty repairs are carried out by Kern or by a Kern dealer.

Technical details

Scope of delivery

• OKO 178 metallurgical microscope
• Simple polarisation unit (analyser and polariser)
• HWF 10x eyepiece with 0.1 mm scale
• Blue filter
• Dust cover
• Eyecups
• Operating instructions (multilingual)

Individual requirements and procurement service

We can arrange a 100x oil immersion objective, additional objectives, filters, eyepieces, an object holder, a camera with a C-mount adapter or a cleaning set for the OKO 178 on request. Please use our procurement service for this.