In the era of resistive touchscreens, there was always an air gap between the matrix and the sensor layer, which was one of the necessary elements of the technology. With the advent of capacitive technology, the need for an air gap disappeared, but manufacturers have been making device screens with the same air gap for a long time. Then, screens appeared on the market in which there was no air gap, and somehow it happened that at first the lack of air between the sensor layer and the matrix was the lot of expensive devices and flagships.
Now this difference has long been erased, and there are inexpensive devices on sale equipped with OGS-type screens, in which instead of air there is a transparent gel between the layers, so the image on such a screen looks clearer (there is no ghosting of the picture due to the reflection of the layers) and more colorful.
A long time ago, from the very first time I got to know OGS technology, I was tempted to try modifying an inexpensive two-piece display by filling a void with gel. However, as is often the case, years passed from idea to experiment. Now this experiment is almost meaningless, but sometimes it is worth doing something insignificant in order to then succeed in more serious matters.
Work front assessment
Today we will be removing the air gap from the inexpensive Teclast tablet, which is currently working as a navigator in the car. By the way, this tablet has already been the hero of one material, which describes the process of restoring the contact pads at the microUSB connector.
Despite the fact that, in an amicable way, the tablet is long overdue for a long time, it performs its function regularly, it makes no sense to throw it away, but for an experiment it just suits – it's not a pity.
The main goal of this experiment is to increase the contrast of the display, remove glare and highlights, thereby improving readability in bright sunlight, and at the same time to find out if the touch will fail after filling LOCA.
First, let's evaluate how the device's screen is behaving now. The image is typical for similar devices. It noticeably lacks contrast.
It is necessary to disassemble our ward to assess the scope and feasibility of work.
In this model, the matrix is also part of the supporting frame on which the board and battery are mounted. In addition, the matrix is separated from the touchscreen by a plastic edging, on which the matrix and the touchscreen are attached from different sides.
Considering this, you will have to cut off this very inner edging, since otherwise the glued touch and matrix cannot be installed in the tablet. Well, let's get started.
Cut off the edging so that the matrix can easily enter the body from the front side. In this way, we will then install the glued parts in place.
After that, we try on the display for free entry into the frame (in this case, just a design that is not very successful for such work), usually nothing has to be cut, since the matrix is most often held by a touchscreen and does not have such a complex design as here.
After trying on, it's time to pour. We take out LOCA.
We prepare surfaces, cleaning them from dust and lint. By the way, if you clean the surfaces with alcohol, you don't have to worry about small stains from alcohol – LOCA will perfectly hide them.
Having prepared the surfaces, we take out the UV oven.
Now you need to fill the touchscreen with glue. You need to fill it with 'fish', so that then the glue spreads evenly in all corners, leaving no unfilled edges.
I will fill in the frame in order to correctly center the display, since after the UV oven it will no longer be possible to correct the position of the matrix and our newly made module simply will not fit into the case. I turned the module over for photo only. Do not do this.
The main risk in this case is associated with the design feature LCD – displays. UV glue has a very high penetrating power (about like honey), so the biggest risk is to flood the backlight, or rather, a reflective layer, which will cause stains on the display later. This will not damage the matrix itself, but the reflective layer will have to be changed. Therefore, we pour glue not on the matrix, as is usually done, but on the touchscreen so that the matrix is on top and the glue does not flow into it. I hope everything works out.
We make sure that the glue spreads over the entire surface and does not leave non-glued areas (it was not possible to take a photo, since both hands were occupied …
If everything is in order, without removing the frames and without turning the module upside down, we grab the current position by putting the sandwich in the UV oven for a few seconds.
After the glue has set, remove the frame so as not to give the glue an extra opportunity to flow into the backlight. We remove excess glue around the edges and bake the resulting module in the oven.
After baking, it remains only to collect the resulting 'Frankenstein's beast' and check the performance of this cadaver.
The touch is not buggy, there are no phantom clicks, and the usual ones work out wonderfully. This is a success.
Unfortunately, I poured a little more glue than needed, and therefore the glue in the corner still flowed into the backlight. But just a little bit. Not scary. But invaluable experience was gained. Then you can disassemble and wipe with alcohol.
But the image does not double and it became noticeably more contrasting (it's a pity the photo does not convey the difference well).
As many will probably say, it was possible not to suffer and buy a normal tablet or a normal navigator. It was possible, but finding a navigator with an OGS display is not so easy. And the goal is not quite that. I wanted to check my guesses regarding the possibility of such an upgrade. This thought did not leave me for more than two years, but until now my hands somehow did not reach. This happens when you want something, but don't do it; over time, the action loses its relevance and it seems that you can not do it. That's just the realization that you could try and did not try, does not let go and makes you mentally return to this again and again, giving rise to a feeling of incompleteness that poisons life.
This experiment proved that such a decision has the right to life, since the result is visible with the naked eye. The picture has become more saturated, the colors brighter. The image has ceased to double, and the sun does not blind the screen so much, allowing you not to peer into it. Was it necessary? As an experiment with minimal risks, yes. Now, after 'running in the technology', my friend's Galaxy Mega 6.3 is next in line. We will increase the contrast, brightness and vibrant colors of the display.
P.S. By the way, I try to never use a smartphone as a navigator for a long time, since in this mode, due to a static picture and the need for external power, the battery and display degrade much faster.