One approach is transparency. Using that approach, there are two main head-worn
display technologies developed in the industry today:
- • Non-Transparent: Most of the display choices are non-transparent. The display device generates an image and then the image is reflected or routed to the user’s eye. Examples in this category include projectors, retinal image lasers, liquid crystal displays (LCDs), ferroelectric liquid crystals on silicon (FLCoS), and liquid crystal on silicon (LCoS). There are also direct-view OLED microdisplays.
- • Transparent: Transparent displays are OLEDs and possibly contact lens with micro light-emitting diodes (LEDs).
Another approach is by the type of technology used. For example, microdisplays and flat panels and/or reflective versus emissive. Most augmented reality see- through headsets use microdisplays and most virtual reality headsets use flat panels. The exception is the Meta 2 which uses a large OLED flat panel and then very large optics (essentially dual spherical combiners like are used in some HUD displays).
Even OLED that could be see-through are used as non-see-through devices. Therefore, his distinction may not get the reader anywhere.