YouTuber Matthew Perks, AKA DIY Perks, Exhibiting self-made dual-layer LCD monitor Earlier this week. This is a naive answer to the LCD dimming problem, an attempt to improve contrast by deepening blacks in LCD displays. It utilizes a pair of LCD panels from a commercially available monitor.
There are several popular computer monitor technologies available today. First, there are LCD monitors with a full white backlight that covers the entire screen. In this type of monitor, the color and black are produced by the liquid crystal either passing colors that do not affect the backlight (white) or trying to block light (black). LCD IPS monitors usually appear as a distinct dark gray in the darkest areas, but LCD VA monitors do a little better in this regard. Also, LCDs can exhibit backlight bleed due to a perfectly bright white light behind the pixels. Modern LCDs may employ dimming zones where the backlight can be turned off for better contrast, and there are more zones that work with the monitor firmware for more sophisticated local dimming . There are also screens with more grainy backlight technology called mini LED displays and micro LED displays. We don’t need to go into them here, but we also mention OLED, where each screen pixel is its own light source. Therefore no backlight is required.
The first idea DIY Perks tried, in search of a more OLED-like display on a budget, was to have two identical monitors, place one panel in front of the other, and add black. It was to have a thickening effect. One monitor was left alone and the other was stripped to a very thin and delicate display panel (no backlight).
Unfortunately, on my first try, I found the 2-panel darkening effect to be so strong that I could not see the image at all. Undeterred, DIY Perks analyzed the problem and found that it was due to the overlapping polarizing layers. As a stopgap solution, he found that placing his paper tracings between panels could do much the same thing. After overcoming this hurdle, it was determined that the overall image quality was poor, not just the black areas.
The obvious next step in tackling the dim problem was to boost the monitor’s backlight. The source monitor used only backlighting from the edges, so Perks decided to create stronger backlighting by filling the entire background with a matrix of LEDs. Tracing paper was again used to avoid visible light peaks and valleys, but had to be placed slightly above the illumination array for the best diffusing effect.
For the new system to work, I had to take the remaining monitor’s LCD and place it on top of the other display (separated with tracing paper). Once this was done, the YouTuber did an admirable job of assembling the experimental dual monitor into a thick but practical case with a power supply, controller board, and ample cooling.
DIY Perks was very clear about the successes and limitations of his projects. The result is a mix of successes and shortcomings.
Upon initial launch, image contrast was said to be impressive, but when windows opened and text/UI elements were displayed on screen, a “weird softness” was observed. Softer text was attributed to dual monitors with dual tracing paper layers, described as a subtle drop shadow effect.
Moving on to one of the main purposes for which this monitor was designed: gaming, Perks was very pleased with the results. Admire the strong contrast and vivid colors. It’s hard to capture this kind of effect on camera and show it on media like YouTube (and screenshots), but the photos help show how the project worked.
DIY Perks admits that the main drawback of the two-tier design is power consumption. Apparently, the backlight array in this example uses 250W. Moreover, the peak brightness of the resulting monitor was slightly darker than the unmodified single sample.
If you want to build one of these DIY dual layer LCD monitors, check out the official DIY Perks forum. guidanceand even have suggestions on how to make it better than the video example. One of the most interesting suggestions could lead to removing at least one of the layers of tracing paper.
