Photonics Dictionary

A lens blank is a piece of optical material in a raw, unfinished state, typically in the form of a disk or block, from which lenses are eventually fabricated. Lens blanks are made from various...

The concave portion of a surface, formed on a blank, on which the disk of higher refractive glass will be fused to form a multifocal spectacle lens.

A grating with very coarse rulings to match the long wavelengths in the far-infrared region. In the most efficient ruling method, grooves are cut in plane, solid aluminum alloy blanks.

In the optical shop, the process of positioning and marking a blank or lens before surfacing, cutting and edging.

The production of rough glass lens blanks that are pressed while red-hot to the approximate size and shape of the finished lens, ready for fine grinding and polishing. Large companies often do their...

A blank to which a piece of glass of a different refractive index will be fused to form a multifocal lens.

A blank whose basic surface curves are attained by heating and forming a given weight of raw glass; a rough glass blank resembling the finished lens in size and shape. After molding, a precision lens...

A block that can hold more than one lens or blank.

Optical glass refers to a type of glass specifically engineered and manufactured for use in optical components and systems, such as lenses, prisms, mirrors, and filters. Optical glass is...

The process whereby pitch is broken and the lenses or blanks are removed from the block.

A term used to describe a spectacle lens or blank with one surface totally finished.

A metal tool used to hold a number of lens blanks during grinding and polishing.

Fluid used to aid in examination of semifinished blanks.