What is the advantage about monochrome lcd display? Why we still need monochrome lcd display even color tft lcd is more and more popular, And do you know how many technology types for monochrome lcd display? Let’s introduce in the following:
Advantage of monochrome lcd:
Monochrome lcd could be in the simple interface such as in I2C interface, SPI interface, 6800/8080 parallel interface, that is we could connect it to the cheaper MCU, and make our system in cost competitive.
On the other hand, monochrome lcd is the better in power saving, it is easily to make the transflective lcd display that most suitable for outdoor application or for battery power devices.
The monochrome lcd have the TN display lcd and STN LCD, and the new monochrome tft lcd mode.
What is TN lcd display:
TN lcd means twisted nematic LCD, the namatic liquid crystal elements inside the lcd glass cell,its twisted angle is 90 degree, intergrated the front and rear polarizes on the lcd, the polarized angle is also in 90 degree in cross, it control the light transmission and make the tn lcd display on and off.
TN lcd display is based on the precisely controlled realignment of liquid crystal molecules between different ordered molecular configurations under the action of an applied electric field. This is achieved with little power consumption and at low operating voltages.
What is STN LCD?
STN lcd is super-twisted nematic lcd display, it is a type of monochrome lcd display, it is also passive liquid crystal display (LCD). compare to TN lcd, STN LCD twist angle is 240 degree, instead of 90 degree of TN LCD, so we call it STN LCD. STN lcd have yellow-green display mode, gray,black-white mode, blue display mode, available. The yellow-green STN LCD means the lcd background with yellow-green mode, but its display characters is black. While the blue mode STN lcd, its background is blue mode with white display pixels. Black-white lcd means the white background with black display pixels (positive mode) or black background with white display colors.
Monochrome tft lcd display:
The monochrome tft lcd is the monochrome type of tft lcd screen, compare to color tft lcd, it is without RGB color filter inside the tft lcd cell, so it display in monochrome type. But because tft lcd is active lcd display type, it is without cross-talk problem as TN or STN lcd, monochrome tft lcd could achieve higher display contrast that traditional monochrome TN or STN lcd display.
TN lcd means (twisted nematic) LCD, the namatic liquid crystal elements inside the lcd glass cell,its twisted angle is 90 degree, intergrated the front and rear polarizes on the lcd, the polarized angle is also in 90 degree in cross, it control the light transmission and make the tn lcd display on and off. TN display is based on the precisely controlled realignment of liquid crystal molecules between different ordered molecular configurations under the action of an applied electric field. This is achieved with little power consumption and at low operating voltages.
What STN display:
STN lcd is super-twisted nematic lcd display, it is a type of monochrome passive-matrix liquid crystal display (LCD). compare to TN lcd, STN LCD twist angle is 240 degree, instead of 90 degree of TN LCD, so we call it STN LCD, This new type of LCD was invented at the Brown Boveri Research Center, Baden, Switzerland, in 1983
1. Outline sizes of custom lcd (length, width, thickness) : as we talked before, because the monochrome custom lcd mother glass always would be in 14”x16”, so the custom lcd panel sizes would not be exceed 14”x16” at the max, actually, regarding the evenness of lcd panel, ideally, one unit of lcd size would not exceed 1/2 of 14”x16”, if bigger than this size, the lcd production ratio would be decreased to very low, we don’t suggest to make the size exceed 1/2 of 14”x16”.
2. Viewing area of custom lcd screen: Mots of time, the custom lcd display viewing area is up to the electronic device’s cover, and also up to the custom lcd frame inside the lcd cell, because there would be at least 1.2~1.5mm distance from the lcd inner frame to lcd edge, so it is necessary to cover this inner frame by the device’s frame, so the distance from viewing area to lcd edge would be at least 1.2~1.5mm.
3. Display pattern of custom lcd screen(graphic display or icon display): of course, the display pattern is decided by the whole devices application, if the custom lcd display screen would be used inside an Automotive’s audio display, some display icons such as “ Play” ,”stop”, “return” etc… button would be needed in the display pattern.so a segment custom lcd display or icon lcd would be suitable. If you like to display text in the monochrome lcd display, custom graphic lcd is necessary, such as 128x32 graphic COG lcd module, 128x64 dots matrix lcd module, 240x160 pixels, or 320x240 pixels graphic lcd module. The more characters or pictures you would like to display, or higher DPI you would like, then you would need more pixels inside the custom lcd screen. But if you only display some simple characters or simple icons in the custom lcd module, you don’t need to use graphic lcd, a icon display or a 16x2 characters lcd or 20x4 characters is enough for your application. Otherwise, you choose the graphic lcd module, you have to pay more cost on your custom lcd screen.
4. Display mode of custom lcd display (TN or STN display mode): The display mode of custom monochrome lcd, at the first, we could choose TN display mode or STN display based on the display patterns or the dots of graphic lcd, if for icon display, a TN display mode should be enough for your application.
built with ST7789V controller IC, it support MCU 8 bit interface. RGB interface is also possible.
1.54’’ square tft display description:
|
Display Size |
1.54 inch square tft (Diagonal) |
|
Resolution |
240(RGB)X 240 |
|
Module Dimension |
31.50(W)x 35.00(H)x1.80(T) mm |
|
Active Display Area |
27.72(W)×27.72 (H) mm |
|
Viewing Direction |
All |
|
LED Backlight Color |
White LEDx3 |
|
Driver IC |
ST7789V |
|
Interface |
MCU |
|
Luminance |
250 nits |
|
Touch screen |
Optional PCAP |