Olympus U-RLA Reflected Light Illuminator

The Olympus U-RLA is a reflected light vertical illuminator providing brightfield and darkfield epi-illumination for Olympus BX series upright microscopes. In a reflected light vertical illuminator, the tungsten-halogen lamp filament is positioned near the principal focal point of the collector lens, enabling Köhler-quality illumination of the specimen surface through the objective. Light travels down through the objective, strikes the specimen surface, and reflects back up through the same objective to the observer — producing even, high-quality reflected light images of opaque specimens. In brightfield mode, the directly reflected beam is collected for standard surface observation. In darkfield mode, the direct beam is blocked and only obliquely scattered light is collected, revealing surface defects, grain boundaries, scratches, and fine topographic features with high contrast against a dark background. The U-RLA is the brightfield/darkfield reflected light illuminator in the Olympus BX accessory range — distinct from the U-URA universal illuminator, which additionally supports fluorescence epi-illumination via a filter cube turret. Built to Olympus factory specifications (catalog number 5-UR300), the U-RLA delivers consistent reflected light performance for materials and industrial microscopy applications. This unit is in excellent condition at a significant discount from the list price.