Shutter Glasses

[icr00]

Hello,

This is my first post on the forum and to be honest I know very little about electronics so I’m looking for a bit of help with something...

I want to create a special pair of glasses. They are too help someone with impaired vision improve his sight as a form of vision therapy.

The glasses should function like standard stereoscopic / 3D shutter glasses. That is, they should use LC lenses that can alternate on and off so that one lens is clear and the other opaque.

However, with these glasses I want to be able to control the alternating frequency with some kind of dial or knob. I want to be able to set the frequency within the range of about 0.2Hz - 20Hz or thereabouts.

The glasses are not to be used with a TV so no synchronization is required. All they have to do is alternate on and off at a controllable frequency.

Obviously I could start with a standard off-the-shelf pair of shutter glasses and then modify them. They don't have to look good - they can be very clunky so long as they work - and they only need to be worn for around 5 minutes at a time so aesthetics are not an issue.

My problem is that I don't have much of a clue about how to do this. I know that the lenses will turn opaque when I apply a voltage to them and then I guess that I need to convert a DC voltage into a square wave AC voltage with some kind of timing solution... but that’s about as far as it goes!

So I have a couple of questions:

1) Is this something that a novice could do without too much difficulty and if so could anyone provide any help with this?

2) Alternatively, would anyone consider building this for me (I would pay you, of course)?

Many thanks,

Iain

 

[Externet]

Welcome.
You can reach me via email at my username at inorbitdotcom, or direct messaging.

----> https://www.electro-tech-online.com/threads/rapid-alternating-occlusion-glasses.153653/#post-1324900
Post 9 at ----> https://www.scienceforums.net/topic...s-cross-eyed-see/?tab=comments#comment-902465

 

[duke37]

I would think this is well inside your capability but it may be easier to get someone else to do it who has the right tools and bits and is familiar with soldering.

A 555 chip can make an oscillator running in the frequency range you require and has a fairly powerful output stage which may drive the glasses directly. Presumably a battery would be used for power and a box would need to be made to house the gigger.

 

[Alec_t]

In the interests of safety, make sure that any user of these glasses does not suffer from epilepsy. Sudden light brightness variations at frequencies in that range are known to trigger epileptic seizures in susceptible people.

 

[Harald Kapp]

The glasses are not to be used with a TV so no synchronization is required. All they have to do is alternate on and off at a controllable frequency.

I think these should be used with sunlight only. When used with artificial lighting ugly aliasing artifacts called beat frequencies may occur (the link is about acustic beat frequencies, but the principle is the same for light - remember wagon wheels of stage coaches in old western movies seemingly turn backwards?).

 

[icr00]

Thanks for all the responses. I agree with the sunlight comment and also the person is not epileptic. I also want to stress that I would start at a very low shutter speed (eg. 3s between each cycle) and increase slowly over days/weeks.

The 555 chip looks like the right thing and yes I would want to power with just some small DC batteries.

However, I think it's currently beyond my skills at the moment, nor do I have any of the right tools etc.

So I think I'd be looking for someone to volunteer their services!

Cheers.

 

[duke37]

You could use LEDs to provide the light. A stabilised DC supply would be needed.

Where are you?
What voltages/currents are needed to switch the glasses?