How much the reflection of the black color in print and paint?
Hello to all optical designers and signboard builders who require anti-reflective black color. I'm Teppei and we develop and sell ultra black anti-reflective sheet "FineShut" at KOYO Orient JAPAN.
It's sudden, but have you ever thought about how the black level for the black painting or black printing on signboards is evaluated?
We are evaluating black level by the index of " Total reflection".
According to its result, the total reflectance of black paint on signboards is from 3% to 10% or so on.
Even the total reflectance of 3% to 10% is good enough for general use, so usually it is no problem.
But there are some applications where you want to suppress the overexposure caused by the reflection.
For example, take the 2D barcode. If any part of it is missing due to the overexposure, accurate information cannot be conveyed.
In addition, target markers for calibration use must be clearly visible without overexposure at any lighting environment.
Our FineShut SP has a total reflectance of 1.2% in visible light. So, it is far less reflective and is a more black color compared with black painting. Here are examples of improvements by using FineShut as a seal instead of printing or painting. Because the following is based on the actual project, it has been modified a little, then please consider it as only a reference.
Solved the problem of 2D code sign overexposure
Today's client looks worried about something.
This company has an automatic patrol device using cameras which recognize 2D code signs.
Although it is instruced action by printed 2D code signs, but sometimes recognition errors occur.
It seems that these errors are caused by the overexposure light reflection from the room light.
All right let's solve it by FineShut!!
Let's make Non-reflective signboard !
I can't show the actual 2D code sign, so I made a QR code signboard for my example. I asked for a non-glossy finish print to a major printing service company.
Well, here is the non-glossy panel sample by typical print.
The same pattern is lined up so that you can compare with FineShut added version and no-added version.
The problem without the FineShut is ....
its reflection. It has so much overexposure, then it can't be recognized as a QR code.
This is caused by the LED light on the ceiling.
So, we will make the right side of this panel to Anti-reflection type by putting on our FineShut.
First, we convert the illustrator file (or DXF or PDF with vector data) of the artwork to machining data for the laser cutting.
Considering making it thinner, we selected the combination of FineShut SP0.2 (t=0.2mm) and thin double-sided tape this time.
The total thickness is 0.27mm. Appearance after laser cutting is like this.
Half cutting was done to the transparent PET separator of the double-sided tape, so this is just tied together by the separator.
From here, stick the necessary parts onto the panel as a seal.
Sorry for forgetting to take photos, but we use water sticking method when we stick them. With this sticking method, we use the water which is added dishwashing detergent in, so it makes the adhesiveness reduce for easy positioning.
Because the seal stickiness is low when it is wet, we can easily re-apply putting them to the correct position at many times.
Ban, Ba, Bang!
Here the one. The right side is treated with Anti-reflective treatment by FineShut seal. eh? Can't see the difference?
It will be obvious if you incline it. Finally, anti-reflective signboard that can protect the light reflection has been made.
The thickness of Anti-reflection area is only 0.27mm, so it seems it is no problem even if you see in a diagonal direction.
I also took a video for easier understanding.
Now the overexposure problem of 2D code has been solved!
This is also the best solution for making AR marker such as ArUco codes.
Anyone who are in trouble with light reflection by printing or painting method, we recommend you use our anti-reflective solution "FineShut".
We offer One-stop support from sheet selection to design, cutting and pasting.
Please contact us by e-mail or contact form for your quotation!