URI
Notation
681.7
Caption
Optical apparatus and instruments
Including
Lenses. Fibre-optic devices. Magnifiers. Microscopes. Spectacles. Telescopes. Binoculars
Application Note
Details of optical instruments by 62-1/-9
See also
520Astronomical instruments and techniques
535Optics
617.7Ophthalmology. Eye disorders and treatment
666.1Glass industry. Glass technology. Glass manufacture in general. Glass in the comprehensive sense
77Photography and similar processes
Broader class
681  Precision mechanisms and instruments