Project NiteVision - NiteMax + HUD + carputer

**Genesisfactor** · 08-11-2006, 09:07 PM

i want to know what film they used. the double image was our biggest problem and it seems to solve that.

**Peoples** · 08-11-2006, 09:43 PM

Originally Posted by Genesisfactor

i want to know what film they used. the double image was our biggest problem and it seems to solve that.

sounds like mirror tint. or something very similar.

**Yevmeister** · 08-11-2006, 09:53 PM

mild mirror tint is what they used, like i said since led's are bright they don't need anything strong, for lcd, we will need darker mirrow tint

Yev

**Genesisfactor** · 08-12-2006, 01:50 AM

ah i see, i was just curious on how they managed it.

**alpha_maverick** · 08-12-2006, 01:33 PM

http://www.mp3car.com/vbulletin/show...832#post744832

what are your thoughts on this?

**Genesisfactor** · 08-12-2006, 01:53 PM

Originally Posted by alpha_maverick

http://www.mp3car.com/vbulletin/show...832#post744832

what are your thoughts on this?

that being MY worklog...
...and linked to in my sig...

I think its a well written piece of work on a promising idea that is only not executed due to the loss of the car. The individual has some interesting ideas on a modular design and news to get ovver his accident induced ADHD and other newfound cognitive disorders to get his act together and finish his HUD, get the voice control on the AI and HTPC and PPC working properly, get the UI right

**alpha_maverick** · 08-12-2006, 02:48 PM

sorry, wrong link. I feel like an idiot. I am using Linux, so I just middle-clicked, thinking that this was the last thing I had highlighted.

in it, it says it uses 50/50 reflective combiner. I am pretty sure that this is the only way to get rid of the ghost image.

in order to get it to focus at some arbitrary distance, I believe that 3 lenses are required. set the assembly focal point to near the drivers head (after reflection) and fine tune it to get the apparent distance you want.

I am in the process of a motor swap, so I do not have the funds to attempt this right now, but I am fairly certain that it will work.

**Genesisfactor** · 08-12-2006, 03:52 PM

That is defintiely more interesting than your last link

. dont' worry we all make mistakes. If you can research this 50/50 combiner, that would be cool!

**shotgunefx** · 08-12-2006, 04:10 PM

Originally Posted by Genesisfactor

That is defintiely more interesting than your last link

. dont' worry we all make mistakes. If you can research this 50/50 combiner, that would be cool!

I don't think it's just a 50/50 "two way" mirror (which I'm planning to buy for experimenting btw), they use it for teleprompters, and samples are available on ebay cheap. I think under 10 bucks. Just search for "two way mirror" and you'll find the seller.

A few problems I see with the type of pictured system, it's big, in a passenger car, would most likely be a big hazard to someone's skull mounted on the ceiling.

You'll also have what amounts to a extremely bright flashlight shooting out of the windshield. Not a problem for the military, but for street use, I think it would get you lot's of unwanted attention.

I really think the only way you can project a hud on a budget (as opposed to reflecting one, which isn't such a bad idea and it's easy) is to oriented it such that the light source isn't viewable from your position, (ie from near the bottom) but then you have to worry about the image being distorted.

Though that would be an easier thing to work around. You'd basically have to scale the scanlines smaller as you reached the top of the screen. But at least the transorm is linear and there are plenty of optimized algorithims for scaling scanline "textures". I'm certain almost all gpus are optimized for this nowadays.

If you were using something like OpenGL or D3D, you could just paint the image frame on a plane and tilt it away from you.

**alpha_maverick** · 08-12-2006, 04:28 PM

a combiner is the same as a beamsplitter. 50/50 means that 1/2 is reflected and half is allowed to pass through. some are directional, meaning that from one direction, nothing (not much) is reflected, but from the other side, it's half and half. http://www.edmundoptics.com/onlineca...productid=2035

Reflected and projected are the same thing!!!! you are not focusing the image on the plate! you focus it on your retina (or near it)! you align the optics to reflect the light so that it is (relatively) square to your eye-level and adjust the focus so that the image appears at the end of the hood, etc. kinda like the focus knob of binoculars.

GTG, more later