Creating high-contrast optical mask?

[papaborat]

I hope this is the right forum; if not, I apologize in advance. I'm working on a 3d face scanner project, where I have a camera and a DLP projector very close to each other. This wikipedia entry titled "Structured Light 3D Scanner" explains very well what I'm trying to do.
Basically, I take a picture of the face and within 100ms take another picture but with a projected binary (stripes) pattern (using an optical mask).
The DLP projector has a visible light filter attached, so only near IR light is transmitted.
What I have done is printed a binary black/opaque pattern onto a transparent sheet. However, the black does not completely block the transmitted light.
Hence, I was wondering whether there is a chemical substance with which I can create a high-contrast optical mask (so the black is really black)? Or does anybody know of any commercial products? Thanks!

 

[chemisttree]

I would suggest a metal vapor-deposited mask. A thick enough metal foil deposited onto a sheet will block all of the light.

 

[quicknote]

Hello,

I would recommend exploring the use of materials such as carbon black or other light-absorbing pigments to create a high-contrast optical mask. These materials have high light absorption properties and can be incorporated into a transparent sheet to create a dark, opaque pattern. Additionally, you may want to consider using multiple layers of the material to increase the contrast and minimize any light leakage. Another option could be using a liquid crystal material that can switch between transparent and opaque states, allowing for precise control over the contrast of the mask.

In terms of commercial products, there are various companies that specialize in optical masks and light control materials for scientific and industrial applications. I would suggest researching and reaching out to these companies to see if they have any products that may meet your specific needs.

I hope this helps and good luck with your project!

Best,