Table 1

Specifications and features of the two video magnification head mounted devices currently available in the UK (manufacturer/supplier data)

Maximum magnification∼10.5× (for distance)∼19×
∼15× (for near) ∼60× as a CCTV
Maximum field of view∼50° horizontally∼25° horizontally
∼40° vertically∼20° vertically
Video displayBinoc (CRT)Binoc (LCD)
Vertical display resolution (TV lines)250200
Contrast/edge enhancementyesyes
Contrast reversalyesyes
Image stabilisationnoyes
Refractive correctionadjust device opticsspectacle prescription worn
Headset weight (g)∼1133∼651
Approximate cost (£)40003000
  • The LVIS requires auxillary plus lenses in order to achieve maximum magnification at near.