Donegan Thread Counter Linen Tester Magnifier

The Donegan thread counter and linen tester magnifier has a round optical-grade lens in a cubed shaped body that folds semi-flat, is available in a variety of lens sizes, and comes in multiple magnification power (X) at specified focal lengths, or distance from object. This magnifier enhances the size and resolution of an object or image, and is commonly used for a variety of applications such as linen inspection, graphic arts, engraving, jewelry-making, watch-making, needlework, artwork, electronic inspection, fly-tying, book-reading, print inspection, and stamp-collecting.

This magnifier features a round lens mounted on the top of a three-dimensional cube (which folds to a semi-flat shape), and has a hollow bottom and sides to allow for maneuverability and placement of an object below the magnifier. A square-framed bottom has interior measurement markings to help assist in the examination process. Its optical-grade lens (available in a variety of sizes) has been ground and polished into a prismatic lens, and is available in multiple magnification powers (X) at specified focal lengths, or distance from object. The magnifier has a one-year limited warranty.

Magnifiers are devices used to enlarge the visual appearance of an object or image. Magnifiers come in a variety of styles such as hand-held, headband, standing, clip-on, eye loupe, and those that hang in a necklace form, or fit in a trouser pocket. Magnifiers are commonly made of plastic or glass. They can have one or more lenses with varying magnification abilities, and can have a binocular configuration with a single lens, or two separate lenses. They are sometimes used with LED or fluorescent light sources to help control viewing capabilities. Magnifier ability is often expressed as magnification at a specific length. For example, 1.75X at 14” means that when a magnifier is held at 14” from a viewer’s eyes, the object will be magnified 1.75 times (X) its actual size. As magnification increases, viewing areas and focal length decrease. Magnifiers sometimes have a diopter number, expressed as + or -D, which is a measurement of strength (or power) of the lens. Some magnifiers are marked with a dioptric number on the lens. A high diopter number has a higher magnification than a low diopter number. Aspheric magnifiers, unlike spheric magnifiers, produce a sharp image to the edge of the lens for less distortion. Magnifiers are widely used in jewelry inspection and fabrication, watch-making, needlework, artwork, fly-tying, electrical inspection, reading, print inspection, and stamp-collecting.

Donegan Optical manufactures and distributes precision visual devices for hobbyists and professionals in industry, home, office and crafts applications. The company was founded in 1952 and is headquartered in Lenexa, Kansas.

What’s in the Box?

• Thread-counter and linen tester magnifier
• Vinyl carrying pouch
• Instruction manual