Suruga Seiki F531-20 Adjustable Mirror Holder with Coated Optical Element

Japanese-made Suruga Seiki F531-20 compact optical mirror holder supplied with the circular coated optical element and mounting hardware shown. This precision mechanical mount provides two-axis angular adjustment for positioning an optic in an optical bench or laboratory assembly. The installed optic displays yellow-green and blue-violet coloration under the photographed lighting. Its individual manufacturer, optical function, coating specification, and substrate material have not been identified. The F531-20 designation applies to the holder. MANUFACTURER-PUBLISHED HOLDER SPECIFICATIONS The following are catalog specifications for the F531-20 holder, not measured or independently verified specifications for the installed optic: Nominal supported mirror diameter: 20 mm Supported mirror thickness: 3–6 mm Nominal optical-axis height: 25 mm Adjustment axes: θy and θz, providing two-axis angular positioning Catalog angular travel: ±3° Fine-adjustment screw pitch: 0.25 mm Catalog angular adjustment per screw revolution: 30 arcminutes, equivalent to 0.5° Holder construction: black-anodized aluminum Catalog holder weight: approximately 0.06 kg, excluding additional components VISIBLE ASSEMBLY DETAILS Two knurled manual adjustment knobs Spring-loaded adjustment mechanism Circular optical element installed in the holder Two front retaining collars secured with Phillips-head screws Base plate with threaded and counterbored mounting holes Open-back construction providing access behind the optic Suruga Seiki branding and “Made in Japan” marking Model marking: F531-20 Additional engraved identification: 11200554-12 INSTALLED OPTIC The circular optic has a reflective, colored surface appearance. It may be a coated mirror, optical filter, or beamsplitter; its precise function is unverified. Substrate material, coating type, operating wavelength, transmission/reflection ratio, surface flatness, focal properties, and laser-damage threshold are not specified. No claim is made that it is a focusing lens or that it is suitable for a particular laser wavelength or power level. CONDITION Pre-owned, with visible scuffs, scratches, finish wear, and dust or surface marks. Please examine the close-up photographs for the condition of the mount, retaining hardware, and optical surfaces. Optical performance and mechanical adjustment accuracy have not been verified. The item is not represented as calibrated or tested to manufacturer specifications. INCLUDED One Suruga Seiki F531-20 mirror-holder assembly Installed circular coated optic Attached base plate, adjustment hardware, and retaining hardware shown No additional optics, mounting posts, optical breadboard, tools, or documentation are included. ITEM SPECIFICS Brand: Suruga Seiki Model / MPN: F531-20 Type: Two-Axis Adjustable Optical Mirror Holder Nominal Holder Size: 20 mm Holder Material: Black-Anodized Aluminum Optical Element Material: Unconfirmed Country of Manufacture: Japan Quantity: One assembly You will receive the exact assembly pictured. Please verify dimensions and optical requirements for your intended application before purchase.