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Project NiteVision - NiteMax + HUD + carputer
Hey one and all,
I am creating a heads-up-display on my windshield (about 7"). What would the best thing be to do to get the brightest image out of a reflection off of the windshield? I have a 7" lilliput in combination with a polarizer on the windshield, but I am in need of more brightness. What would you advise?
One of the thing that I am trying to do is not mentioned in that forum. I want to have a set of lenses sit over my display so when it reflects through the windshield, I will be able to see the image a further distance away, but still see it with clarity. Does anyone have any insight on this problem?
Also, the thread referred to above doesn't really come to a conclusion as to a plausible solution for a HUD. Help?
and I think that's really where the project sits. I believe that post has the most information regarding the topic yet there's still no resolute solution that people have put in place and are consistently using.
I have put much thought to this and am hoping to achieve something very similar if not identical to what you want. However, there is a major sticking point with using a 7 inch display, you will need 'alot' of lenses and hence it will have to be mega bright! when you look at modern HUDs they have very high resolution and are ultra bright at the same time verey small, even more so for helmet mounted (obviously).
There is a really good site here that talks about helmet mounted displays I recommend you download the wholee thing and read it. It gets interesting when you can cacpture the image you are seeing too through combiners/prisms etc.
I have had a go at trying to design the optical system but it is a bit out of my depth. I know I will need a double convex lens at the start, but my calculations made it almost 30cm think. I don't think you will be able to reflect it of the windshield either as the laminate will causes several reflections due to the different refractive indexees of glass/plastic/glass etc.
I found some good paperes and boks but they were wawy too expensive for a mere hobbist like myself. the library here sucks and don't have any of them in.
and some papers
I am going to try using a pda screen and then upping the brightness considerably. My main reason for this is as I get oldere my eyes take longer to focus on the dials and then back to the road, I want something that hovers at infinite focus in my FOV so i don't need to re focus and detract my attention from the road!
To get infinite focus the light from the display must be collimated, hence it is much easier to achieve witha smaller or spherical display (crt). I have attached a simple pic of what we are trying to achieve, the focal length will be how far in front of the car you want the image to be in focus.