Electronic and optical apparatus and instruments that incorporate optical apparatus and devices, namely, optical transmitters, optical receivers, optical transceivers, optical reflectors, image intensifiers, optical condensers, optical filters, eye pieces for helmet mounted displays; apparatus for recording, transmission or reproduction of sound or images, incorporating optical apparatus and devices; data processing equipment, incorporating optical apparatus and devices; optical glasses; optical lenses; helmets incorporating optical apparatus and devices, namely, virtual reality head-mounted displays, augmented reality head-mounted displays; diffractive optical units, substrate-guided optical units, optical beam steering units, and light-guides for optical units and electronic apparatus, all being structural parts of apparatus for reproduction or transmission of images used in virtual reality and augmented reality applications; light transmittance and reflectance substrates being structural parts of optical lenses and optical glasses; image display devices, namely, near eye displays for use in displaying augmented reality and virtual reality images; head mounted displays in the nature of virtual reality headsets and augmented reality headsets; hand-held displays in the nature of hand-held video displays; optical beam and image expanders; optical switching units being structural parts of apparatus for reproduction or transmission of images used in virtual reality and augmented reality applications; optical polarizers; structural parts and fittings for the aforesaid goods