Astronomical spectrographs; Audiovisual receivers; Cable connectors; Data cables; Electron microscopes; Measuring rulers; Microscopes; Optical lens sights; Scanners; Signal processors; Telescopes; Audio speaker enclosures; Distance measuring apparatus; Downloadable computer software to enhance the audio-visual capabilities of multimedia applications, namely, for the integration of text, audio, graphics, still images, and moving pictures; Loud speaker systems; Optical devices, namely, eye piec...