Loupe

A loupe (pronounced loop), is a type of magnification device used to see things one is looking at more closely. In this respect, they are simply a form of a modified microscope, allowing the user to be able to better apply the phenomenon of microscopy to his or her trade.

Commercial uses of loupes
Loupes are used in a number of different of industries, notably the jewelry trade, photography, printing, ophthalmology and dentistry.

Jewelers
Jewelers typically use a monocular, handheld loupe in order to magnify gemstones and other jewelry that they wish to inspect. A 10x magnification is good to use for inspecting jewelry. A 10x loupe is the standard instrument used to determine a diamond's clarity grade in the gemological industry. While higher-power magnification devices may be used to examine the stone, inclusions (internal flaws) and blemishes (surface irregularities) are not factored into the stone's final clarity grade if they are small enough to be undetectable when the stone is examined under 10x magnification.

Electronics
For many soldering applications engineers and technicians will use a loupe to inspect a printed circuit board with small surface components on it.

Printing
Offset printing sees frequent use of loupes in order to carefully analyze how ink lays on paper. Strippers use loupes in order to register film separations to one another. Pressmen use them to check registration of colors, estimate dot-gain, and diagnose issues with roller pressure and chemistry based on the shape of individual dots and rosettes.

Photography
Photographers use loupes to review, edit or analyze negatives and slides on a light table.Photographers using large format cameras also use loupes for viewing the ground glass image to aid focussing

Dentistry
Many dentists will use loupes to better scrutinize the entities within their patients' mouths in order to make a better diagnosis, for example, to determine how far a crack proceeds along the surface of a tooth. Loupes are also used in order to perform on a more precise level; while dentists drill teeth on a millimeter scale, magnification can enlarge the dentists' view of the teeth, perhaps making it easier to inspect teeth for decay and/or see things that ordinarily would not be seen without magnification.

Specialties of dentistry, such oral surgery and periodontics, may benefit from the use of loupes as well. Even though they may be performing surgical procedures on the gingiva or bony structures of the oral cavity, the oral cavity is notorious for being a place containing small entities with limited access. Magnification can be very helpful when suturing a flap.

Because dentists use both of their hands while performing dental procedures, dental loupes are binocular and usually take on the form of a pair of glasses. Some dental loupes are flip-types, which take the form of two small cylinders, one in front of each lense of the glasses. Other types are inset within the lense of the glasses. A typical magnification for use in dentistry is 2.5x, but dental loupes can be anywhere in the range from 2x to 5x.

Together with proper access to the oral cavity, light is an important part of performing precision dentistry. Because a dentist's head often eclipses the overhead dental lamp, loupes may be fitted with a light source. This light source, emanating from in front of the loupes, cannot be blocked by the position of the dentists' head, and so provides for a continuous source of light during the extent of dental procedures. Loupe-mounted lights used to be fed by fiber optic cables that connected to either a wall-mounted or table-top light source, and often introduces a limiting range for the dentist, as he or she would be required to remain close to the wall or table, respectively. Additionally, the fiber optic cord can be damaged by excess flexing or crushing, such as would occur should the cord be rolled over by a chair. Newer models feature an LED lamp within the loupe-mounted light and an electric cord coming from either the conventional wall-mounted/table-top light source or a belt clip rechargeable battery pack. Options for loupe-mounted cameras and video recorders are also available.