tft lcd monitor wiring diagram quotation

In this Arduino touch screen tutorial we will learn how to use TFT LCD Touch Screen with Arduino. You can watch the following video or read the written tutorial below.

As an example I am using a 3.2” TFT Touch Screen in a combination with a TFT LCD Arduino Mega Shield. We need a shield because the TFT Touch screen works at 3.3V and the Arduino Mega outputs are 5 V. For the first example I have the HC-SR04 ultrasonic sensor, then for the second example an RGB LED with three resistors and a push button for the game example. Also I had to make a custom made pin header like this, by soldering pin headers and bend on of them so I could insert them in between the Arduino Board and the TFT Shield.

Here’s the circuit schematic. We will use the GND pin, the digital pins from 8 to 13, as well as the pin number 14. As the 5V pins are already used by the TFT Screen I will use the pin number 13 as VCC, by setting it right away high in the setup section of code.

I will use the UTFT and URTouch libraries made by Henning Karlsen. Here I would like to say thanks to him for the incredible work he has done. The libraries enable really easy use of the TFT Screens, and they work with many different TFT screens sizes, shields and controllers. You can download these libraries from his website, and also find a lot of demo examples and detailed documentation of how to use them.

After we include the libraries we need to create UTFT and URTouch objects. The parameters of these objects depends on the model of the TFT Screen and Shield and these details can be also found in the documentation of the libraries.

So now I will explain how we can make the home screen of the program. With the setBackColor() function we need to set the background color of the text, black one in our case. Then we need to set the color to white, set the big font and using the print() function, we will print the string “Arduino TFT Tutorial” at the center of the screen and 10 pixels  down the Y – Axis of the screen. Next we will set the color to red and draw the red line below the text. After that we need to set the color back to white, and print the two other strings, “by” using the small font and “Select Example” using the big font.

tft lcd monitor wiring diagram quotation

The traditional mechanical instrument lacks the ability to satisfy the market with characters of favorable compatibility, easy upgrading, and fashion. Thus the design of a TFT-LCD (thin film transistor-liquid crystal display) based automobile instrument is carried out. With a 7-inch TFT-LCD and the 32-bit microcontroller MB91F599, the instrument could process various information generated by other electronic control units (ECUs) of a vehicle and display valuable driving parameters on the 7-inch TFT-LCD. The function of aided parking is also provided by the instrument. Basic principles to be obeyed in circuits designing under on-board environment are first pointed out. Then the paper analyzes the signals processed in the automobile

instrument and gives an introduction to the sampling circuits and interfaces related to these signals. Following this is the functional categorizing of the circuit modules, such as video buffer circuit, CAN bus interface circuit, and TFT-LCD drive circuit. Additionally, the external EEPROM stores information of the vehicle for history data query, and the external FLASH enables the display of high quality figures. On the whole, the accomplished automobile instrument meets the requirements of automobile instrument markets with its characters of low cost, favorable compatibility, friendly interfaces, and easy upgrading.

The digital instrument has functions of vehicle information displaying, chord alarming, rear video aided parking, LED indicating, step-motor based pointing, and data storage. The instrument adopts dedicated microcontroller MB91F599, a 7-inch LCD, and two step-motors to substitute for the traditional instrument. All the information generated by other ECUs can be acquired via not only the sample circuits but also the CAN bus.

The CAN bus interface and the 7-inch TFT-LCD make it more convenient to upgrade the instrument without changing the hardware. If the software needs to be upgraded, we need not bother to take the instrument down and program the MCU. Instead, we can upgrade the instrument via the vehicle’s CAN network without taking the instrument down, which makes the upgrading more convenient. Most of the information from other ECUs can be transmitted via the CAN bus; so, we do not have to change the hardware circuits if some of the ECUs’ signals are changed in different applications. Besides, since most of the driving parameters are displayed on the TFT-LCD, and the graphical user interface can be designed with great flexibility by programming, only the software needs to be revised to meet different requirements of what kind of driving parameters to display and so forth. These characters, together with the reserved interfaces, enhance the instrument’s compatibility in different applications.

On the one hand, there are some automobile instruments which adopt 8-bit MCUs or 16-bit MCUs which have limited peripherals, so it is difficult for them to meet some requirements such as rearview video and high real-time data processing performance. And many extra components are needed if the designer wants to accomplish some functions such as video input. On the other hand, there are some advanced automobile instruments which adopt high performance MCUs (such as i.MX 53, MPC5121e, and MPC5123) and run Linux on them. They even use larger TFT-LCDs (such as the 12.3-inch TFT-LCD with a resolution of 1280 × 480 pixels) to display driving parameters. These automobile instruments show higher performances than the instrument in this paper. However, they are more expensive than this automobile. This instrument is able to provide almost all the functions of the advanced automobile instrument with a lower cost.

The instrument receives signals from other ECUs via the sampling circuits or the CAN bus interface. It can also receive commands from the driver via the button interface. The signals are then processed by the MCU, after which the MCU may send the vehicle information to the LCD or light the LEDs and so forth, according to the results. Therefore, the automobile instrument can be viewed as a carrier of the information flow. And the design of the system can be viewed from two aspects: the hardware system and the information flow based on it.

Since the FLASH size of the microcontroller is only 1 MB which is limited for the storage of pictures displayed on the LCD, external FLASH is needed to store different kinds of meaningful pictures such as the background of the dial. Two S29GL256N chips with a memory capacity of 256 Mb are chosen for picture data storage for their high performance and low power consumption. The application circuits of the chips are provided in their datasheets, so it is unnecessary to go into the details of them here.

The 7-inch TFT-LCD has a resolution of pixels and supports the 24-bit for three RGB colors. The interface of the 60-pin TFT-LCD can be categorized into data interface, control interface, bias voltage interface, and gamma correction interface.

The data interface supports the parallel data transmitting of 18-bit (6 bits per channel) for three RGB colors. Thus, a range of colors can be generated. The control interface consists of a “horizontal synchronization” which indicates the start of every scan line, a “vertical synchronization” which indicates the start of a new field, and a “pixel clock.” This part is controlled by the graphics display controller which is integrated in the MB91F599. We just need to connect the pins of the LCD to those of the microcontroller correspondingly.

Bias voltages are used to drive the liquid crystal molecules in an alternating form. The compact LCD bias IC TPS65150 provides all bias voltages required by the 7-inch TFT-LCD. The detailed circuit is also provided in the datasheet of TPS65150.

The greatest effect of gamma on the representations of colors is a change in overall brightness. Almost every LCD monitor has an intensity to voltage response curve which is not a linear function. So if the LCD receives a message that a certain pixel should have certain intensity, it will actually display a pixel which has intensity not equal to the certain one. Then the brightness of the picture will be affected. Therefore, gamma correction is needed. Several approaches to gamma correction are discussed in [20–22]. For this specific 7-inch LCD, only the producer knows the relationship between the voltage sent to the LCD and the intensity it produces. The signal can be corrected according to the datasheet of the LCD before it gets to the monitor. According to the datasheet, ten gamma correction voltages are needed. These voltages can be got from a resistive subdivision circuit.

For this instrument, the LED indicators, the backlight, and the chord alarm need to be supplied with a voltage of +12 V; the CAN transceiver, the EEPROM, and the buttons need to be supplied with a voltage of +5 V; the video buffer circuit, the external FLASH, and the data interface of the LCD need to be supplied with a voltage of +3.3 V. Besides, the microcontroller needs to be supplied with voltages of +5 V and +3.3 V simultaneously. Figure 8 offers a detailed block diagram of the power supply for the automobile instrument.

The main task for the program is to calculate the driving parameters of the vehicle and display them on the TFT-LCD. The calculation is triggered by the input signals via the sampling circuits or the CAN bus. The main program flow chart of the system is shown in Figure 10.

The design scheme of a TFT-LCD based automobile instrument is carried out form aspects of both the hardware and the main program flow chart. The MB91F599 simplifies the peripheral circuits with its rich on-chip resources and shows high performance in real-time data processing. The automobile instrument is capable of displaying the velocity of the vehicle, the engine speed, the cooling water temperature, the oil pressure, the fuel volume, the air pressure, and other information on the TFT-LCD, which contributes a lot to driving safety and satisfies drivers’ aesthetics. Besides, the rearview video makes the parking and backing easier and safer for the driver. Moreover, the CAN bus interface and TFT-LCD make it easier for the upgrading of the instrument without changing the hardware, thus saving the cost.

tft lcd monitor wiring diagram quotation

I"m using the below code to test a 2.2" TFT (ILI9341 based). When I use software SPI the display works but very slow. Whne I switch to hardware SPI, the backlight is ON but the display does not show anything.

tft lcd monitor wiring diagram quotation

Hi guys, welcome to today’s tutorial. Today, we will look on how to use the 1.8″ ST7735  colored TFT display with Arduino. The past few tutorials have been focused on how to use the Nokia 5110 LCD display extensively but there will be a time when we will need to use a colored display or something bigger with additional features, that’s where the 1.8″ ST7735 TFT display comes in.

The ST7735 TFT display is a 1.8″ display with a resolution of 128×160 pixels and can display a wide range of colors ( full 18-bit color, 262,144 shades!). The display uses the SPI protocol for communication and has its own pixel-addressable frame buffer which means it can be used with all kinds of microcontroller and you only need 4 i/o pins. To complement the display, it also comes with an SD card slot on which colored bitmaps can be loaded and easily displayed on the screen.

Due to variation in display pin out from different manufacturers and for clarity, the pin connection between the Arduino and the TFT display is mapped out below:

We will use two libraries from Adafruit to help us easily communicate with the LCD. The libraries include the Adafruit GFX library which can be downloaded here and the Adafruit ST7735 Library which can be downloaded here.

We will use two example sketches to demonstrate the use of the ST7735 TFT display. The first example is the lightweight TFT Display text example sketch from the Adafruit TFT examples. It can be accessed by going to examples -> TFT -> Arduino -> TFTDisplaytext. This example displays the analog value of pin A0 on the display. It is one of the easiest examples that can be used to demonstrate the ability of this display.

The first thing, as usual, is to include the libraries to be used after which we declare the pins on the Arduino to which our LCD pins are connected to. We also make a slight change to the code setting reset pin as pin 8 and DC pin as pin 9 to match our schematics.

Next, we create an object of the library with the pins to which the LCD is connected on the Arduino as parameters. There are two options for this, feel free to choose the most preferred.

tft lcd monitor wiring diagram quotation

Hi guys, over the past few tutorials, we have been discussing TFT displays, how to connect and use them in Arduino projects, especially the 1.8″ Colored TFT display. In a similar way, we will look at how to use the 1.44″ TFT Display (ILI9163C) with the Arduino.

The ILI9163C based 1.44″ colored TFT Display, is a SPI protocol based display with a resolution of 128 x 128 pixels. It’s capable of displaying up to 262,000 different colors. The module can be said to be a sibling to the 1.8″ TFT display, except for the fact that it is much faster and has a better, overall cost to performance ratio when compared with the 1.8″ TFT display. Some of the features of the display are listed below;

TheTFT Display, as earlier stated, communicates with the microcontroller over SPI, thus to use it, we need to connect it to the SPI pins of the Arduino as shown in the schematics below.

Please note that the version of the display used for this tutorial is not available on fritzing which is the software used for the schematics, so follow the pin connection list below to further understand how each pin of the TFT display should be connected to the Arduino.

In order to allow the Arduino to work with the display, we need two Arduino libraries; the sumotoy TFT ILI9163C Arduino library which can be downloaded from this link and the popular Adafruit GFX Arduino library which we have used extensively in several tutorials. Download these libraries and install them in the Arduino IDE.

For today’s tutorial, we will be using the bigtest example which is one of the example codes that comes with the sumotoy ILI9163C Arduino library to show how to use the TFT display.

The example can be opened by going to File–>Examples–>TFT_ILI9163c–>bigtest as shown in the image below. It should be noted that this will only be available after the sumotoy library has been installed.

Next, an object of the ILI9163c library named “display” was created with CS and DC parameter as inputs but due to the kind of display being used, we need to include the pin of the Arduino to which the A0 pin of the TFT display is connected which is D8.

tft lcd monitor wiring diagram quotation

A thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display that uses thin-film-transistor technologyactive matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven (i.e. with segments directly connected to electronics outside the LCD) LCDs with a few segments.

In February 1957, John Wallmark of RCA filed a patent for a thin film MOSFET. Paul K. Weimer, also of RCA implemented Wallmark"s ideas and developed the thin-film transistor (TFT) in 1962, a type of MOSFET distinct from the standard bulk MOSFET. It was made with thin films of cadmium selenide and cadmium sulfide. The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968. In 1971, Lechner, F. J. Marlowe, E. O. Nester and J. Tults demonstrated a 2-by-18 matrix display driven by a hybrid circuit using the dynamic scattering mode of LCDs.T. Peter Brody, J. A. Asars and G. D. Dixon at Westinghouse Research Laboratories developed a CdSe (cadmium selenide) TFT, which they used to demonstrate the first CdSe thin-film-transistor liquid-crystal display (TFT LCD).active-matrix liquid-crystal display (AM LCD) using CdSe TFTs in 1974, and then Brody coined the term "active matrix" in 1975.high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.

The circuit layout process of a TFT-LCD is very similar to that of semiconductor products. However, rather than fabricating the transistors from silicon, that is formed into a crystalline silicon wafer, they are made from a thin film of amorphous silicon that is deposited on a glass panel. The silicon layer for TFT-LCDs is typically deposited using the PECVD process.

Polycrystalline silicon is sometimes used in displays requiring higher TFT performance. Examples include small high-resolution displays such as those found in projectors or viewfinders. Amorphous silicon-based TFTs are by far the most common, due to their lower production cost, whereas polycrystalline silicon TFTs are more costly and much more difficult to produce.

The twisted nematic display is one of the oldest and frequently cheapest kind of LCD display technologies available. TN displays benefit from fast pixel response times and less smearing than other LCD display technology, but suffer from poor color reproduction and limited viewing angles, especially in the vertical direction. Colors will shift, potentially to the point of completely inverting, when viewed at an angle that is not perpendicular to the display. Modern, high end consumer products have developed methods to overcome the technology"s shortcomings, such as RTC (Response Time Compensation / Overdrive) technologies. Modern TN displays can look significantly better than older TN displays from decades earlier, but overall TN has inferior viewing angles and poor color in comparison to other technology.

The transmittance of a pixel of an LCD panel typically does not change linearly with the applied voltage,sRGB standard for computer monitors requires a specific nonlinear dependence of the amount of emitted light as a function of the RGB value.

Initial iterations of IPS technology were characterised by slow response time and a low contrast ratio but later revisions have made marked improvements to these shortcomings. Because of its wide viewing angle and accurate color reproduction (with almost no off-angle color shift), IPS is widely employed in high-end monitors aimed at professional graphic artists, although with the recent fall in price it has been seen in the mainstream market as well. IPS technology was sold to Panasonic by Hitachi.

Less expensive PVA panels often use dithering and FRC, whereas super-PVA (S-PVA) panels all use at least 8 bits per color component and do not use color simulation methods.BRAVIA LCD TVs offer 10-bit and xvYCC color support, for example, the Bravia X4500 series. S-PVA also offers fast response times using modern RTC technologies.

A technology developed by Samsung is Super PLS, which bears similarities to IPS panels, has wider viewing angles, better image quality, increased brightness, and lower production costs. PLS technology debuted in the PC display market with the release of the Samsung S27A850 and S24A850 monitors in September 2011.

TFT dual-transistor pixel or cell technology is a reflective-display technology for use in very-low-power-consumption applications such as electronic shelf labels (ESL), digital watches, or metering. DTP involves adding a secondary transistor gate in the single TFT cell to maintain the display of a pixel during a period of 1s without loss of image or without degrading the TFT transistors over time. By slowing the refresh rate of the standard frequency from 60 Hz to 1 Hz, DTP claims to increase the power efficiency by multiple orders of magnitude.

Due to the very high cost of building TFT factories, there are few major OEM panel vendors for large display panels. The glass panel suppliers are as follows:

External consumer display devices like a TFT LCD feature one or more analog VGA, DVI, HDMI, or DisplayPort interface, with many featuring a selection of these interfaces. Inside external display devices there is a controller board that will convert the video signal using color mapping and image scaling usually employing the discrete cosine transform (DCT) in order to convert any video source like CVBS, VGA, DVI, HDMI, etc. into digital RGB at the native resolution of the display panel. In a laptop the graphics chip will directly produce a signal suitable for connection to the built-in TFT display. A control mechanism for the backlight is usually included on the same controller board.

The low level interface of STN, DSTN, or TFT display panels use either single ended TTL 5 V signal for older displays or TTL 3.3 V for slightly newer displays that transmits the pixel clock, horizontal sync, vertical sync, digital red, digital green, digital blue in parallel. Some models (for example the AT070TN92) also feature input/display enable, horizontal scan direction and vertical scan direction signals.

New and large (>15") TFT displays often use LVDS signaling that transmits the same contents as the parallel interface (Hsync, Vsync, RGB) but will put control and RGB bits into a number of serial transmission lines synchronized to a clock whose rate is equal to the pixel rate. LVDS transmits seven bits per clock per data line, with six bits being data and one bit used to signal if the other six bits need to be inverted in order to maintain DC balance. Low-cost TFT displays often have three data lines and therefore only directly support 18 bits per pixel. Upscale displays have four or five data lines to support 24 bits per pixel (truecolor) or 30 bits per pixel respectively. Panel manufacturers are slowly replacing LVDS with Internal DisplayPort and Embedded DisplayPort, which allow sixfold reduction of the number of differential pairs.

Kawamoto, H. (2012). "The Inventors of TFT Active-Matrix LCD Receive the 2011 IEEE Nishizawa Medal". Journal of Display Technology. 8 (1): 3–4. Bibcode:2012JDisT...8....3K. doi:10.1109/JDT.2011.2177740. ISSN 1551-319X.

K. H. Lee; H. Y. Kim; K. H. Park; S. J. Jang; I. C. Park & J. Y. Lee (June 2006). "A Novel Outdoor Readability of Portable TFT-LCD with AFFS Technology". SID Symposium Digest of Technical Papers. AIP. 37 (1): 1079–82. doi:10.1889/1.2433159. S2CID 129569963.

tft lcd monitor wiring diagram quotation

The transmission (luminance) versus the applied voltage characteristic is shown in Fig. 11. The shown characteristic is for normal viewing angle and indicates that grayscale levels can be achieved by varying the voltage across the LCD. Unfortunately, the transmission – voltage curve is viewing angle dependent, leading to grayscale errors and color shift in a display when it is viewed from significant angles to the display normal.

The equivalent circuit with the parasitic elements of a pixel cell and a typical TFT-LCD pixel layout are shown in fig. 12. The pixel consists of a switch TFT device, with the gate electrode connected to the row driver lines and the source electrode connected to the column driver lines. Furthermore, a storage capacitor is connected in parallel to the LC pixel capacitance.

The aperture part is the light transparent part and it is designated for the placement of the liquid crystal while the TFT, voltage lines and storage capacitor areas are non-light transparent. The ratio between the transparent portion of a pixel and its surrounding electronics is called aperture ratio or fill factor. Furthermore, in the shown layout design, the storage capacitor is connected to an adjacent row line resulting in the maximization of the aperture ration but the load capacitance of the row lines is, also, increased. The counter electrode of the LC pixel capacitor is the common ITO electrode on the opposite substrate (Den Boer, 2005). For large displays, this configuration is difficult to be used due to the large RC delay time of the row lines. In order to overcome this problem, a common storage bus can be placed in the aperture area which reduces the load capacitance of the row lines, but also reduces the aperture ration of the pixel.

A full color LCD display can be generated by incorporating red, green and blue color filters at the pixels. In order to produce the desirable color tone, the pixel is divided into three sub-pixels each one having red, green and blue color filter, respectively. The three sub-pixels have the same dimensions and the proper combination of each color tone; by applying the right voltages to the liquid crystals, the desired pixel emissive colour will be produced. The width of each sub-pixel is three times smaller than the sub-pixel length and when the three sub-pixels are very closely placed in parallel, a square full color pixel is produced. Figure 14 shows a full colour square pixel.

tft lcd monitor wiring diagram quotation

Vin: PWB input voltage (12V)VDD: ASIC, source IC, gate IC driving power (3.3v)VGH: TFT component switching voltage (~30V)VGL: TFT component turn-off voltage (~ -6v)VAA: step control voltage (~17V)VCOM: liquid crystal reversal reference voltage (~7V)

4. #Press the LCD glass side of the panel, if the vertical lines disappear or reappear, it can be judged that the cause of poor contact, OM checking should be able to find the poor contact.

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tft lcd monitor wiring diagram quotation

The DT022BTFT uses the same connections as the DT022CTFT, with the exception of the backlight (which has connections shown in the Displaytech datasheet).

Note that the WR pin becomes the D/CX signal in serial mode. CS is used to initiate a data transfer by pulling it low. At the end of the data transfer, pull the CS pin high to complete the transaction. The timing diagram indicates that you can pull the CS pin high in between the command byte and data bytes within a transfer, but it is unlikely needed if the display is the only device on the SPI bus. To keep things simple, we suggest to leave it low during the entire transaction.

The D/CX pin tells the ILI9341 that the current byte is either command or data. Pull the D/CX pin low when the current byte is a command, and pull high when it is data. The timing diagram indicates only needing to set D/CX on the last bit of a byte, but it is much simpler to just leave it high or low during the entire byte.

tft lcd monitor wiring diagram quotation

Note that the WR pin becomes the D/CX signal in serial mode. CS is used to initiate a data transfer by pulling it low. At the end of the data transfer, pull the CS pin high to complete the transaction. The timing diagram indicates that you can pull the CS pin high in between the command byte and data bytes within a transfer, but it is unlikely needed if the display is the only device on the SPI bus. To keep things simple, we suggest to leave it low during the entire transaction.

The D/CX pin tells the ILI9341 that the current byte is either command or data. Pull the D/CX pin low when the current byte is a command, and pull high when it is data. The timing diagram indicates only needing to set D/CX on the last bit of a byte, but it is much simpler to just leave it high or low during the entire byte.

tft lcd monitor wiring diagram quotation

The monitor is shock and vibration-proof, automatically adjusts the brightness of the image to the ambient light, has a mirror-image correction and offers the ability to add mark lines per camera on the image for optimum assessment of the distance between the machine or the vehicle and any objects.

tft lcd monitor wiring diagram quotation

Ambu® aView™ is a portable high resolution monitor that is compatible with all of Ambu´s single-use flexible scopes including Ambu® aScope™ 4 Broncho and Ambu® aScope™ 4 RhinoLaryngo.

tft lcd monitor wiring diagram quotation

The CPX1 -27 square rackmount LCD displays offer all the features you need for your harsh environment application. This extremely rugged, military-grade display is engineered to meet MIL-S-901E and MIL-STD-810G. The LCD is best in class offering revision controlled long product availability. It can be driven from multiple video sources including DVI-D, HDMI, DisplayPort or optionally 3G HD-SDI. It supports Picture-In-Picture or Picture-By-Picture to allow multiple video streams to be viewed at once. It is designed for the harshest of environments constructed off aircraft grade aluminum, optically bonded LCD cover glass and locking stainless steel hardware.

Display26.5″ Square LCD1920×1920 Resolution5mm Bonded Cover Glass StandardAnti-Reflective Coating on Cover GlassContrast Ratio: 1000: 1Brightness: 300 cd/m2Picture-in-Picture and Split Screen

tft lcd monitor wiring diagram quotation

Thin-Film Transistor Liquid Crystal Displays use thin-film transistors to control the voltage applied to the liquid crystal layer at a sub-pixel level. The structure of TFT LCDs consists of a TFT “sandwich” and a BLU (Backlight Unit). A typical configuration is shown in the schematic diagram below.

Firstly, between the back and front polarizers, TFT LCD cells are made with two glass substrates – one for color filters, the other for a TFT array – and a liquid crystal layer sandwiched in between.

For normally black TFT LCDs, if we follow along a piece of light setting off from its backlight source, it will bea)guided uniformly by LGP;b)reflected and enhanced by BEF and DBEF;c)polarized by the back polarizer;d)polarization changed by twisted LC under the voltage applied by TFT arrays;e)“tinted” red/green/blue by corresponding color filter of the subpixel;f)let through the front polarizer by matched polarization; andg)finally, it will reach the surface and appears in viewer’s eyes.

Normally black LCDs have higher contrast and wider viewing angles without grayscale inversion phenomenon compared to their normally white relatives. And whether TFT LCDs are normally black or white depends on their LC switching mode:

Schematic diagram of the (a) TN mode, (b) VA mode, (c) FFS mode, and (d) IPS mode. *LC orientations shown are under applied voltages. C/F stands for the color filter.