Prescription Smart Glasses
Some companies have taken one additional step in the development of their smart glasses, and added prescription ground lenses. One of the questions often asked of smart glasses manufacturers is, “Can I use it with my glasses?”
Fig. 2.9 This is an integrated augmented commercial reality head-mounted device (Source: Atheer Labs)
As is mentioned later (Laforge, Sect. 6.1.4), as of this writing, only a few companies are offering consumer-class augmented reality eyewear with a normal look.
Rochester Optical, a renowned optical company founded in 1883 by William H. Walker  (1846-1917) has provided prescription lenses that can be used with other firms augmented reality glasses. In November, 2015, Hong Kong Optical Lens Co., LTD established a partnership with Rochester Optical in offering Smart Solutions for five types of smart glasses and providing optical corrections users. Rochester Optical had designed its Smart Solutions optimized for people who felt discomfort while wearing smart glasses. The company developed two types of prescription glasses. Very thin and light frames that can be used under augmented reality headsets (and virtual reality head-mounted displays too), and custom frames that can accept add-in augmented reality displays such as Recon, Vuzix, Epson, Atheer, and others.
Jins Mem also offers type of smart glasses in a conventional frame with prescription lenses. However, they do not have a camera, and connect to a companion application in a smartphone via Bluetooth. They’re equipped with a gyroscope, six-axis accelerometer, and electrooculography (EOG) sensors for tracking eye movement. The Meme smart glasses are designed for fitness tracking and can measure posture and identify when fatigue is setting in.
Fig. 2.10 This is an add-on augmented reality display device (Source: Garmin)
Blue Light Filters
Smartphones, tablets, and displays in augmented reality headsets are common sources of blue-violet light. Close proximity to users’ eyes intensifies the impact, and too much blue light exposure can contribute to eye fatigue, and potentially cause early-onset macular degeneration .
To combat this problem, lenses have been designed that can block harmful blue- violet light emitted by digital devices. Rochester Optical has made this a feature of their lens offerings. Laforge is also adding blue light to their lenses, in addition to UV filtering.
Add-on augmented reality display devices, like the Garmin Varia-Vision, can be attached to sunglasses or prescription glasses (Fig. 2.10).
Add-on displays, or retro-fit displays, are usually limited to monocular presentation. Interestingly, the suppliers seem to favor the right eye, possibly influenced by Google Glass. Steve Mann’s original EyeTap however, was worn over the left eye.
The other augmented reality devices such as contact lenses are discussed in the “Smart contact Lens,” section on Sect. 220.127.116.11.