Last time we talked about some basic specifications of LCD.
5 Things You Need to Know When Choosing LCD screen – mSLA/LCD 3d printers
Today I am going to show you what’s different between the normal RGB screen to the monochrome LCD screen.
As we said the original panels come from professional manufacturers such as BOE、Sharp、JDI、Tianma、LG Display etc, they start making screens for 3D printing now.
Normal RGB LCD
UV light transmission is the core factor in mono LCD. We adjust many elements aim to improve this specification.
- The color filter and blacklight are removed.
- The polarizer improved to suit for monochrome 3D printing.
- The aperture ratio improved which works directly on the transmission rate.
LCD Generation
LCDs, along with OLED displays, are manufactured in cleanrooms using large sheets of glass whose size has increased over time. You can check Wiki here
Several displays are manufactured at the same time and then cut from the sheet of glass, also known as the mother glass. The increase in size allows more displays or larger displays to be made. The glass sizes are as follows:
Most 5.5 inch and 6 inch screens are from GEN 4/4.5 include current Sharp04 and the 6inch monochrome screen. You can also find most LCD screens over the world from this website：https://www.panelook.com/
These manufacturers are focus on the bigger generation with OLED, You can find high-resolution screen use on VR/AR products, which is not used on our printer now, our screen is TFT-LCD.
Below is BOE’s generation with the screen type, the large size LCD mainly uses on TVs, Monitors, Laptops, and mobiles. But I do believe there will be more option for 3D printers in the soon future.
LCD Aperture Ratio
Aperture ratio is the ratio of the area of the light transmission part of the pixel (or sub-pixel) (the area available for display) to the total area of the pixel (or sub-pixel).
As shown in below. The aperture ratio of TFT-LCD is about 50 ∼ 80%. Generally, the larger the aperture ratio, the higher the optical utilization rate of the liquid crystal display, and the higher the brightness of the display.
55% Aperture ratio
80% Aperture ratio
The increase in aperture ratio is mainly determined by the design scheme and process capability.
In the manufacturing process, the alignment accuracy of the array substrate and the color filter substrate will also have a decisive influence on the aperture ratio.
We remove the color filter on the monochrome screen, In the current market, there are two kinds of 6inch monochrome screens.
One is Duobond 5.96 inch, another is Dongxingqiang 6.08 inch(DXQ608/ZXQ608)
RGB LCD screen Pixels
You can see there is no sub-pixel on the monochrome screen anymore.
In the beginning, there was some mono screen have the sub-pixel which make the real image is x3 compare to original setting.
Polarizer Film
Optical performance includes three main indicators: polarization, transmittance, and hue. The higher the degree of polarization and transmittance, the higher the display efficiency of the LCD display device and the lower the energy consumption.
For conventional iodine-dyed polarizers, the degree of polarization and transmittance are a pair of contradictions. The higher the degree of polarization, the lower the transmittance, and it is also restricted by the color tone.
for normal RGB LCD screen the degree of polarization of ordinary polarizers is between 90% and 99%, and the transmittance is between 41% and 44%.
However, the monochrome won’t affect by color tone, we can make more adjustments to improve the transmittance.
Advantages of Monochrome LCD
The printing speed:
This actually talks about decrease exposure time, because the UV transmission can reach 6% on a monochrome screen, and RGB LCD is about 1%. Below you can see ELEGOO Saturn is much faster than Mars.
The lifespan:
The manufacture upgrades the materials to protect the screen better from UV light and adjust the structure a little.
We were told the monochrome can work over 10K hours.
UV light source
The UV light source also needs an upgrade to work with monochrome LCD. It requests more vertical & parallel light to make sure the quality. There will come out the new UV LED for the mono screen soon and CBD-Tech will keep an update.
The ChiTu systems board has supported most mono screen yet and keep providing a better solution.
If you are interested in upgrade your RGB screen to monochrome LCD, Take a look at ChiTu systems online store, and we also the original RGB color screens for mars and photon.
