Monocular head mounted display. I've got my beady eye on you.............................................................................................................
In 2009 I posted an Instructable on how to make a pair of glasses with a head up display to one eye, using a pair of Olympus Eye-Trek video glasses.
My reason for these projects is that I believe wearable displays will become very useful in hospital medicine, particularly anesthesiology.
UPDATE June 2014: Updated much smaller more compact version due very soon with 3D printed shell.
Since then there has been a lot of interest recently due to the current Google Glass project, which puts a head up display in front of one eye in a very neat package resembling a pair of glasses with nose-piece, top frame across over eyes, but no lenses or lens-frames.
Funnily enough monocular displays are much more expensive than binocular ones despite only having the one display as they are perceived as semi-professional devices. The military use rugged versions and also there is a big push to bring them into medical applications.
This is my attempt to make a much better version than last time, somewhat inspired by the Steve Mann Eye-Tap project and also inspired by Martin Magni who has previously hacked the video glasses I intended to use. Specifically the aims this time are:
a) Not built into a pair of glasses. Instead we have a nose-bridge to locate one end, then a springy strap runs around the back of the head to a small pad under the ear on opposite side. This arrangement is inspired by a recent concept version of the Eye-Tap (which also originally used a glasses type frame).
b) Several DIY projects out there hack a display from one side of a pair of video glasses then mount it in an arm on a glasses frame in some way, often with a lot of experimentation required to get the correct alignment with the eye. In this project, I simply keep the factory alignment of one side of the video glasses I have used.
c) As small as possible: Most video glasses blot out all forward view and light entering from above and below. I want the exact opposite, I want to wear these while doing other things, so I want to see with one eye, and with the "video" eye also be able to see in stereo if I look up or down.
Although the display looks very close to my eye, I can easily see what I am doing in stereo if I look down normally (not all the way down, just glance downwards is enough). This is the advantage of the very slim display.
Many video glasses because they are wide and block out light, can tend to have a flat circuit board running the full width of the part in front of the face. This makes hacking them to make a one-eye display not impossible but tricky.
The Myvu-Crystal glasses are great as they are essentially two displays, with a separate cable to each side, linked in centre over the nose. The quality is pretty good and yet each display is physically very small.
I have a 3D printer and original plan was to remove the electronics of the display units and embed one in a printed structure over my eye. However the more I thought about it, the more I realised that the Myvu-Crystal eyepieces look pretty good anyway, and certainly better than anything I could design and print.
The springy band around the back of the head is actually from a gaming headset which comes with a springy band with a pad on the end, a single headphone, and a small boom microphone.
With some hacking I joined the two together and made a really neat very comfortable minimalist monocular head mounted display.
Also, it comes with an i-Phone / i-Pad / i-PodTouch connector so I can download movies or TV programmes from for example BBC iPlayer, onto an i-PodTouch in my pocket and watch them on the move. If they come out with any decent augmented reality apps in the future, I can use them. Otherwise I will stick to watching films and TV.
Obviously this also might interest the wearable computing community too. Took about 3 hours to do which is vastly less than my first attempt in 2009.
What you need:
Myvu Crystal video glasses or something similar ideally with an iPodTouch / iPad type connection option:
A basic gaming headset, the sort with only one headphone on one side and a pad on the other side.
Dremel with a cutting disk or something similar.
Epoxy glue or a glue gun.
Optionally a very small nut and bolt