custom tft lcd module free sample
Established in 2010, Topfoison has devoted itself to the manufacturing and development of high-quality products for the Wearable device, Smart Watch, VR, Medical device, Industrial LCD display including Color LCD modules/OLED/LCD display/Round lcd screen/Round AMOLED/ Square transflective lcd screen/ IPS full wide display/ 1080p fhd AMOLED and 2K 1440p lcd. Topfoison focus on1.22-7.0 inch small size displays, all the products produced in our company enjoys the most advanced production craft and technology as well as the strictly ISO quality management system.
1.What advantages do you have?A. Fast delivery time, can support sample services, products are in stock, can be supplied at any time, 24 hours online service, products have passed strict certification, and the buyer has good results.2.Q: How can I get the samples?A: Send inquiry → Offer quotation →Confirm quotation & pay tooling charge → Provide drawing → confirm drawing → make tooling & samples → Samples finished → Delivery via freight or sea collect.3.Q: How long can I expect to get the sample?A: Contour drawing: 2-4 days Sample time: 7-15 days.4.Q: Can you design the lcd in acccordance with our demand?A: Sure.We will give you the best tooling charge.5.Q: How to place orders ?A: If you confirm samples ok, Please send us your purchase order by Email or Fax , Then we will send you an Invoice for deposit payment. We need to know the following information of your order.
Our corporation puts emphasis about the administration, the introduction of talented staff, plus the construction of team building, attempting hard to improve the quality and liability consciousness of team members. Our organization successfully attained IS9001 Certification and European CE Certification of Touch Displays, Transparent Lcd, Small Touchscreen Monitor, With a fast development and our customers come from Europe, United States, Africa and all over the world. Welcome to visit our factory and welcome your order, for further inquires please do not hesitate to contact us!
Sticking for the belief of "Creating items of top of the range and creating buddies with people today from all over the world", we normally put the interest of shoppers in the first place for Factory Free sample Lcd Graphic Module - 2.47 inch 480×480 Custom Square Color TFT LCD Display – DISEN , The product will supply to all over the world, such as: Luxemburg, St. Petersburg, Bhutan, We have been making our products for more than 20 years . Mainly do wholesale , so we have the most competitive price , but highest quality. For the past years , we got very good feedbacks , not only because we provide good products , but also because of our good after-sale service . We are here waiting for you for your inquiry.
As a TFT LCD manufacturer, we import mother glass from brands including BOE, INNOLUX, and HANSTAR, Century etc., then cut into small size in house, to assemble with in house produced LCD backlight by semi-automatic and fully-automatic equipment. Those processes contain COF(chip-on-glass), FOG(Flex on Glass) assembling, Backlight design and production, FPC design and production. So our experienced engineers have ability to custom the characters of the TFT LCD screen according to customer demands, LCD panel shape also can custom if you can pay glass mask fee, we can custom high brightness TFT LCD, Flex cable, Interface, with touch and control board are all available.
Sticking towards the theory of "Super Good quality, Satisfactory service" ,We are striving to become a superb business enterprise partner of you for Tft Graphic Display, Wide Screen Tft, Touchscreen Monitor, If you are interested in any of our products, please feel free to contact us for more details. We hope to cooperate with more friends from all over the world.
We insist on offering high quality production with good business concept, honest sales and the best and fast service. it will bring you not only the high quality product and huge profit, but the most significant is to occupy the endless market for Factory Free sample Lcd Graphic Module - 2.47 inch 480×480 Custom Square Color TFT LCD Display – DISEN , The product will supply to all over the world, such as: azerbaijan, Bolivia, European, Welcome to visit our company, factory and our showroom where displays various products that will meet your expectation. Meanwhile, it is convenient to visit our website, and our sales staff will try their best to provide you the best service. Please contact us if you need more information. Our aim is to help customers realize their goals. We are making great efforts to achieve this win-win situation.
As a TFT LCD manufacturer, we import mother glass from brands including BOE, INNOLUX, and HANSTAR, Century etc., then cut into small size in house, to assemble with in house produced LCD backlight by semi-automatic and fully-automatic equipment. Those processes contain COF(chip-on-glass), FOG(Flex on Glass) assembling, Backlight design and production, FPC design and production. So our experienced engineers have ability to custom the characters of the TFT LCD screen according to customer demands, LCD panel shape also can custom if you can pay glass mask fee, we can custom high brightness TFT LCD, Flex cable, Interface, with touch and control board are all available.
Custom TFT LCD services are made to meet users’ specific needs, which significantly increases productivity and efficiency. Therefore, Custom TFT LCD Display Modules have multiple potential benefits to the clients. The first benefit users get to enjoy is the choice of their display size. custom LCD Display modules vary in size and depending on your needs; you can choose large or smaller TFT LCD sizes. As a user, you are free to select portable displays or large displays that are viewed from far.
Custom TFT LCD display modules are designed to your satisfaction, which helps your brand to stand against competitors. The use of generic displays will not set you apart from the people. Therefore, it is imperative to use custom display modules designed with features unique to you or your business. Using unique features will give you a competitive advantage in a market as your displays will stand out.
The custom displays are operated in parallel as well as in series. These two aspects mean that you are at liberty to control how the monitors display items. In parallel, it means that all the screens will show similar adverts, whereas each screen shows different things in series. STONE’s customer support will help you with the technical know-how of how the two are set.
Using a custom LCD display will lower overhead costs because they are designed to operate in a way that suits your business. Besides, most custom display modules come with basic programs, which save hours of programming and installation, thus saving time and cost of labor.
STONE custom LCD Display modules are used in a number of applications such as automation, home appliances, medical devices, point of sale (POS), and factory automation products, among others. These LCD Display modules are uniquely designed to accommodate the environment they will be used in. For example, displays used in healthcare could be subjected to extreme temperature, moisture, and vibrations, which means they need to be enhanced with special coatings to improve durability. Therefore,custom LCD Display manufacturers should consider status in critical environments, especially when designing display modules meant for industrial and factory applications.
As STONE, we understand that every market has a unique set of requirements and functions undertaken on a day-to-day basis. Consequently, we have a wide range of customized TFT Display modules aimed to simplify those daily activities, be it personal or industrial applications. Our custom TFT displays differ in on-screen display size, color schemes, screen contrast, and appearance. For instance, some seek LCD Displays for indoor use under artificial light, whereas others might prefer LCD Displays for outdoor applications. Our high brightness TFT LCD Displays are designed to be sunlight readable. Therefore, STONE will customize your LCD depending on where you need to use them in your field. Additionally, STONE’s custom LCD screen modules are designed to offer optimum performance and excellent contrast and color quality for both indoor and outdoor environments.
Our LCD Display devices come in different sizes to suit your diverse needs. They each vary in cost, but they have high quality and effectiveness. All modules are RoHS and CE compliant with extensive graphics and system library functions.
Orient Display is a company that specializes in manufacturing LCD displays, touch panels, OLED displays with competitive prices. The company was founded in 1996 by specializing in fields of production, R&D, quality controls. Thanks for the management and employee’s continuous hardworking and enormous effort and shareholder continuous investment over years, Orient Display factory is now the world’s leading custom LCD manufacturer in flat panel industry and is listed as a public company in China stock market. Now, Orient Display factory has 2 production lines that can produce PMOLED and AMOLED custom display modules. Factories have complete quality and environment management system, ISO9001, ISO/IATF16949, ISO14001, IECQ QC080000. Orient Display takes around 18% market share in global automotive market and is No.1 in automotive capacitive touch screen.
Orient Display has supported customers with custom LCD displays for tens of thousands of types and models for automotive, appliances, medical, smart homes, point of sales, industrial advices, etc. Whether your design requires a small custom LCD display glass, or a fully customized LCD module, or custom monitors and displays equipped with complicated embedded control board with touch panels, our experienced engineers in North America, Europe or in China factory will assist you in designing your customized displays.
Orient Display customer service sends quotation to you (might come with technical suggestions according to your targeted applications). The time will depend on the complexity of the project and the time to source components, normally, it takes 1-3 days for custom LCD glass panels, 2-5 days for custom LCD display modules or touch panels.
Orient Display engineers provide custom LCD display counter-drawings for you to approve with your signature on the drawing. The drawings might be modified several times until the designs are fully achieved your technical requirements. There can be a lot of technical discussions at this stage. The time our engineers take to arrange drawings also depend on the complexity of the project. Normally, it takes 1-3 days for custom LCD glass panels, 2-5 days for custom LCD display modules or touch panels.
After your drawing approval, Orient Display will start to make samples or prototypes for you to test. The lead time also varies depending on the production complexity and component/material sourcing. Normally, it takes 4-6 weeks for custom LCD glass panels, 8-10 weeks for custom LCD display modules or touch panels.
After your sample / prototype approval, Orient Display is ready for production. Orient Display welcomes trial production between the prototypes to large scale production so that you have the opportunity to fully test the custom LCD display or touch panel to run well in your designed products.
Congratulations! You have accomplished the journey of the idea, design, prototype and production in the market. The journey can take from 3 months to 3 years. Whatever the voyage, Orient Display’s engineers, customer services are proud to be part of your design. Our happiness is based on your success.
Dimensions (Specification / Drawing / Sketch of the LCD, if available). If it is a drop-in replacement, it is great to provide files in dwg. or dxf. format.
LCD Mode Preference if you have an idea or let us to decide (TN Positive/Negative, STN Positive YG, STN Negative Blue, STN Positive Gray, FSTN Positive, FSTN Negative, FFSTN Negative);
Dimensions (Specification / Drawing / Sketch of the LCD module, if available). If it is a drop-in replacement, it is great to provide files in dwg. or dxf. format.
LCD Mode Preference if you have an idea or let us to decide (TN Positive/Negative, STN Positive YG, STN Negative Blue, STN Positive Gray, FSTN Positive, FSTN Negative, FFSTN Negative);
Fully custom made TFT LCD display module can be very expensive, the NRE ranges from $80,000 to $1M depending on the size and the resolution of the LCD display and the generation of the production line the LCD display to be produced. For over 99% of our projects, we are talking about the modifications of the standard TFT LCD display. There are a lot of standard color TFT displays available in the market. You are highly likely to find one matching your requirement. If you can’t find a suitable one on our website, please check with our engineers, we have a database in factory with much more types.
Dimensions (Specification / Drawing / Sketch of the LCD module, if available). If it is a drop replacement, it is great to provide files in dwg. or dxf. format.
Dimensions (Specification / Drawing / Sketch of the touch panel module, if available). If it is a drop replacement, it is great to provide dwg or dxf files.
The above information can be overwhelming. Actually, we design a lot of touch panel and LCD custom display projects without being provided detailed information. Our engineers and customer service can quickly decide the parameters based on the customer’s application. Please feel free to contact our engineers for details.
Dr Pan: Hello, Greg. TFT LCD module is one of the best LCD technology. We can simply consider it as TFT+LCD+LED backlight, and monochrome LCD module consists of LCD+LED backlight. An image on an LCD we can see is composed of pixels. TFT is the abbreviation for thin film transistor and it controls the R, G, B colors of each pixel respectively on the surface of LCD.
TFT LCD is a high standard product and it is not well customized as monochrome LCD. But still, it has a variety of options to meet the customers’ requirements.The sizes range from 1.44 inch to 130.0 inch;
KING TECH is a TFT LCD IPS supplier solution specialist since 2003, we are the group company combined byAn Innolux authorized LCD panel&IC distribution company
We Provide Different Kinds of Custom TFT Display ServicesIf needed we can make custom size tft displays for customers, we have a good relationship with original TFT display module factories, and we can negotiate with them to tool up an LCD panel mask. The tooling cost will be very high and paid by the end customer, and MOQ is at least 25K/lot.
We are capable to change every structure of the TFT display module. To increase backlight brightness and make it sunlight readable, the highest brightness we’ve ever reached was 6500cd/m2.To change the display FPC shape and length. To customize a resistive touch panel(RTP) or capacitive touch panel(CTP/PCAP), we have a long-term cooperation supplier to work with us on such tooling, for CTP, we can also make different shapes and thicknesses of cover glass, single touch, and multi-touch, AG/AR/AF is also available.
With our own PCBA hardware& software design company, we can design different kinds of TFT display modules for our customers, from simple convert boards to complete motherboards, from HDMI driver boards to Android controller boards, from non-touch function boards to capacitive touch function boards, they are all part of our working.
We have our own TFT display module panel and driver distribution department, if you want to switch to another structure of display, we can also help, cause we know which TFT display module panel and the driver is more match, and which suit’s supply is more stable, which one we can get the lowest price.
In order to give the customer the best support, Kingtech, as one of the best TFT LCD IPS suppliers in China, also can provide industrial solutions such as developing a mother board, serial port UART board, T-CON board, HDMI board, and monitor according to the customer"s requirements.
Kingtech also has existing industrial solutions for the PV135 motherboard, PV901 Linux board, and PV804 motherboard. They can be connected between Raspberry pi and our TFT display module, which can make them work together.
For serial port UART board, Kingtech has a 2.8inch 240x320 LCD with serial port UART board, 3.5inch 320x480 module with serial port UART board, 4.3inch 480x272 display with a resistive touch with serial port UART board, 7inch 800x480/1024x600 TFT with capacitive touch with serial port UART board.
For exisiting monitor products, Kingtech has 8inch 1280x800 IPS monitor, 10.1inch 1280x800 monitor, 15.6inch 1280x800 LCD monitor, 12.3inch 1920x720 IPS 850nit LCD monitor, 18.5inch 1366x768 1000nits LCD monitor.
For the HDMI board, Kingtech has a 1.39inch 454x454 AMOLED round with HDMI board, 3.34inch 320x320 TFT round with HDMI board, 3.4inch 800x800 TFT round with HDMI board, 5inch 1080x1080 TFT with HDMI board, 4.3inch 800x480 TFT with HDMI board, 5inch 800x480 LCD with HDMI board, 7inch 800x480/1024x600 LCD display with HDMI board, 10.1inch 1280x800 LCD module with HDMI board.
Above all TFT display modules with board products can be used for industrial equipment, medical, smart-home, or others. Kingtech can also have industrial custom TFT display solutions according to the customer’s requirements. Ware is welcome to contact us. If you are interested in any tft display module products, we can negotiate with you at a reasonable TFT LCD display price. Thank you.
TFT display module is a Thin Film Transistor, and AMOLED is Active-matrix organic light-emitting Display. The TFT display module is backlight-on the liquid crystal panel; AMOLED is a panel that emits light on its own; TFT display module structure is more thick and strong, AMOLED is very thin and also weak, TFT display module is used widely than AMOLED, AMOLED is used in consumer products the most, like a smartwatch, mobile phone, and TV.
IPS is In-Plane Switching, It is also known as free viewing angle, which means the viewing angle of the display on 4 sides is the same, a normal display has its best viewing angle like 6 o’clock or 12 o’clock. While the TFT display module contains normal viewing angles and IPS display,IPS display is a kind of TFT display module.
TFT display module belongs to LCD, LCD is Liquid Crystal Display, it contains mono(single color) LCD and color LCD, single color LCD is barely used now, and color LCD has STN and TFT two types. Therefore, TFT display module is a kind of LCD display.
OLED is Organic Light Emitting Display, it is a display that emits light on its own, and it does not need an extra backlight, so it requests lower power consumption than TFT display module but its lifetime is shorter than TFT(5000 hours), AMOLED is a kind of OLED but it is more colorful. TFT display module requests a backlight to light on and power consumption are higher than OLED, but its lifetime is much longer(20000 hours).
The LED display is working by lighting up the LED lights, the TFT display module is lighted up by the backlight and the liquid crystal starts to work and shows contents. TFT display module has brighter and more true color, and lower price and LED display has lower power consumption, smaller heat, and longer lifetime.
Compares to other types of display, TFT display module is the more widely used, it can be made in different shapes and sizes, from very small sizes to big sizes. The resolution now is higher and higher, and the price of custom TFT display modules is more and more competitive. Its lifetime is longer than the OLED display, and its color is brighter than OLED.
For over 20 years we"ve been helping clients worldwide by designing, developing, & manufacturing custom LCD displays, screens, and panels across all industries.
Newhaven Display has extensive experience manufacturing a wide array of digital display products, including TFT, IPS, character displays, graphic displays, LCD modules, COG displays, and LCD panels. Along with these products, we specialize in creating high-quality and affordable custom LCD solutions. While our focus is on high-quality LCD products, we also have a variety of graphic and character OLED displays we manufacture.
As a longtime leader in LCD manufacturing, producing top-quality LCD modules and panels is our highest priority. At Newhaven Display, we’re also incredibly proud to uphold our reputation as a trusted and friendly custom LCD manufacturing company.
As a custom LCD manufacturing company, we ensure complete control of our custom displays" reliability by providing the industry"s highest quality standards. Our design, development, production, and quality engineers work closely to help our clients bring their products to life with a fully custom display solution.
Our excellent in-house support sets Newhaven Display apart from other display manufacturers. Modifications in the customization process are completed at our Illinois facility, allowing us to provide an exceptionally fast turnaround time.
Customer support requests sent by phone, email, or on our support forum will typically receive a response within 24 hours. For custom LCD project inquiries, our response time can take a few days or weeks, depending on the complexity of your display customization requirements. With different production facilities and a robust supply chain, we are able to deliver thefastest turnaround times for display customizations.
Our excellent in-house support and custom display modifications set Newhaven Display apart from other LCD display manufacturers. From TFTs, IPS, sunlight readable displays, HDMI modules, EVE2 modules, to COG, character, and graphic LCDs, our modifications in the customization process are completed at our Illinois facility, allowing us to provide quality and fast turnaround times.
As a display manufacturer, distributor, and wholesaler, we are able to deliver the best quality displays at the best prices. Design, manufacturing, and product assembly are completed at our headquarters in Elgin, Illinois. Newhaven Display International ensures the best quality LCD products in the industry in this newly expanded facility with a renovated production and manufacturing space.
With assembly facilities in the US, manufacturing facilities in China, and distribution channels worldwide, we pride ourselves on delivering high-quality custom display solutions quickly to locations worldwide.
Focus Displays offers a wide range of standard full color TFT displays. 64 million unique colors, high brightness, sharp contrast, -30C operating temperature, and fast response time are all good descriptions of a TFT display. This is why TFT technology is one of the most popular choices for a new product.
Thin Film Transistor (TFT) display technology can be seen in products such as laptop computers, cell phones, tablets, digital cameras, and many other products that require color. TFT’s are active matrix displays which offers exceptional viewing experiences especially when compared to other passive matrix technologies. The clarity on TFT displays is outstanding; and they possess a longer half-life than some types of OLEDs and range in sizes from less than an inch to over 15 inches.
CCFL’s are still available, but are becoming a legacy (obsolete) component. TFT displays equipped with a CCFL require higher MOQs (Minimum Order Quantities) than displays with LED backlights.
The majority of TFT displays contain a touch panel, or touch screen. The touch panel is a touch-sensitive transparent overlay mounted on the front of the display glass. Allowing for interaction between the user and the LCD display.
Some touch panels require an independent driver IC; which can be included in the TFT display module or placed on the customer’s Printed Circuit Board (PCB). Touch screens make use of coordinate systems to locate where the user touched the screen.
Resistive touch panels are the lowest cost option and are standard equipment on many TFT modules. They are more common on smaller TFT displays, but can still be incorporated on larger modules.
Custom resistive touch screens are an option if the customer requires a seal or gasket to be in contact with the glass and not in contact with the touch panel.
Contrast ratio, or static contrast ratio, is one way to measure the sharpness of the TFT LCD display. This ratio is the difference between the darkest black and the brightest white the display is able to produce. The higher the number on the left, the sharper the image. A typical contrast ratio for TFT may be 300:1. This number ratio means that the white is 300 times brighter than the black.
TFT LCD displays are measured in inches; this is the measurement of the diagonal distance across the glass. Common TFT sizes include: 1.77”, 2.4”, 2.8”, 3”, 4.3”, 5”, 5.7”, 5.8”, 7”, 10.2”, 12.1 and 15”.
TFT resolution is the number of dots or pixels the display contains. It is measured by the number of dots along the horizontal (X axis) and the dots along the vertical (Y axis).
Certain combinations of width and height are standardized and typically given a name and a letter representation that is descriptive of its dimensions. Popular names given to the TFT LCD displays resolution include:
Transmissive displays must have the backlight on at all times to read the display, but are not the best option in direct sunlight unless the backlight is 750 Nits or higher. A majority of TFT displays are Transmissive, but they will require more power to operate with a brighter backlight.
A primary job of the driver is to refresh each pixel. In passive TFT displays, the pixel is refreshed and then allowed to slowly fade (aka decay) until refreshed again. The higher the refresh frequency, the sharper the displays contrast.
The TFT display (minus touch screen/backlight) alone will contain one controller/driver combination. These are built into the display so the design engineer does not need to locate the correct hardware.
If you do not see a Thin Film Transistor (TFT) Display module that meets your specifications, or you need a replacement TFT, we can build a custom TFT displays to meet your requirements. Custom TFTs require a one-time tooling fee and may require higher MOQs.
Ready to order samples for your TFT design? Contact one of our US-based technical support people today concerning your design requirements. Note: We can provide smaller quantities for samples and prototyping.
We"ve got thousands of LCD displays perfect for your design. Whether you need a TFT, LCD, OLED or ePaper display module, we carry them all. We also provide free world-class product support and a full complement of accessories; including touch screens, cables, development boards, and Arduino kits.
LCD Solutions Provider to all your requirements. If you have demands for CUSTOM LCD Products for Character, Graphic, and LCD Glass Panels, we are the best solution for your TFT LCD Modules requirement . We strive to provide uncompromising services to our customers by offering high quality products at very low prices.
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, RinkyDinkElectronics.com 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.
Next we need to define the fonts that are coming with the libraries and also define some variables needed for the program. In the setup section we need to initiate the screen and the touch, define the pin modes for the connected sensor, the led and the button, and initially call the drawHomeSreen() custom function, which will draw the home screen of the program.
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 HowToMechatronics.com” using the small font and “Select Example” using the big font.
Now we need to make the buttons functional so that when we press them they would send us to the appropriate example. In the setup section we set the character ‘0’ to the currentPage variable, which will indicate that we are at the home screen. So if that’s true, and if we press on the screen this if statement would become true and using these lines here we will get the X and Y coordinates where the screen has been pressed. If that’s the area that covers the first button we will call the drawDistanceSensor() custom function which will activate the distance sensor example. Also we will set the character ‘1’ to the variable currentPage which will indicate that we are at the first example. The drawFrame() custom function is used for highlighting the button when it’s pressed. The same procedure goes for the two other buttons.
So the drawDistanceSensor() custom function needs to be called only once when the button is pressed in order to draw all the graphics of this example in similar way as we described for the home screen. However, the getDistance() custom function needs to be called repeatedly in order to print the latest results of the distance measured by the sensor.
Ok next is the RGB LED Control example. If we press the second button, the drawLedControl() custom function will be called only once for drawing the graphic of that example and the setLedColor() custom function will be repeatedly called. In this function we use the touch screen to set the values of the 3 sliders from 0 to 255. With the if statements we confine the area of each slider and get the X value of the slider. So the values of the X coordinate of each slider are from 38 to 310 pixels and we need to map these values into values from 0 to 255 which will be used as a PWM signal for lighting up the LED. If you need more details how the RGB LED works you can check my particular tutorialfor that. The rest of the code in this custom function is for drawing the sliders. Back in the loop section we only have the back button which also turns off the LED when pressed.
Let us start with the basics first; refresh the knowledge about TN and LCD displays in general, later we will talk about TFTs (Thin Film Transistors), how they differ from regular monochrome LCD displays. Then we will go on to the ghosting effect, so we will not only discuss the technology behind the construction of the TFT, but also some phenomena, like the ghosting effect, or grayscale inversion, that are important to understand when using an LCD TFT display.
Next, we will look at different technologies of the TFT LCD displays like TN, IPS, VA, and of course about transmissive and transflective LCD displays, because TFT displays also can be transmissive and transflective. In the last part we will talk about backlight.
Let us start with a short review of the most basic liquid crystal cell, which is the TN (twisted nematic) display. On the picture above, we can see that the light can be transmit through the cell or blocked by the liquid crystal cell using voltage. If you want to learn more about monochrome LCD displays and the basics of LCD displays, follow this link.
What is a TFT LCD display and how it is different from a monochrome LCD display? TFT is called an active display. Active, means we have one or more transistors in every cell, in every pixel and in every subpixel. TFT stands for Thin Film Transistor, transistors that are very small and very thin and are built into the pixel, so they are not somewhere outside in a controller, but they are in the pixel itself. For example, in a 55-inch TV set, the TFT display contains millions of transistors in the pixels. We do not see them, because they are very small and hidden, if we zoom in, however, we can see them in every corner of each pixel, like on the picture below.
On the picture above we can see subpixels, that are basic RGB (Red, Green, Blue) colors and a black part, with the transistors and electronic circuits. We just need to know that we have pixels, and subpixels, and each subpixel has transistors. This makes the display active, and thus is called the TFT display. TFT displays are usually color displays, but there are also monochrome TFT displays, that are active, and have transistors, but have no colors. The colors in the TFT LCD display are typically added by color filters on each subpixel. Usually the filters are RGB, but we also have RGBW (Red, Green, Blue, White) LCD displays with added subpixels without the filter (White) to make the display brighter.
Going a little bit deeper, into the TFT cell, there is a part inside well known to us from the monochrome LCD display Riverdi University lecture. We have a cell, liquid crystal, polarizers, an ITO (Indium Tin Oxide) layer for the electrodes, and additionally an electronic circuit. Usually, the electronic circuit consists of one transistor and some capacitors to sustain the pixel state when we switch the pixel OFF and ON. In a TFT LCD display the pixels are much more complicated because apart from building the liquid crystal part, we also need to build an electronic part.
That is why TFT LCD display technologies are very expensive to manufacture. If you are familiar with electronics, you know that the transistor is a kind of switch, and it allows us to switch the pixel ON and OFF. Because it is built into the pixel itself, it can be done very quickly and be very well controlled. We can control the exact state of every pixel not only the ON and OFF states, but also all the states in between. We can switch the light of the cells ON and OFF in several steps. Usually for TFT LCD displays it will be 8-bit steps per color, so we have 256 steps of brightness for every color, and every subpixel. Because we have three subpixels, we have a 24-bit color range, that means over 16 million combinations, we can, at least theoretically, show on our TFT LCD display over 16 million distinct colors using RGB pixels.
Now that we know how the TFT LCD display works, we can now learn some practical things one of which is LCD TFT ghosting. We know how the image is created, but what happens when we have the image on the screen for a prolonged time, and how to prevent it. In LCD displays we have something called LCD ghosting. We do not see it very often, but in some displays this phenomenon still exists.
Another issue present in TFT displays, especially TN LCD displays, is grayscale inversion. This is a phenomenon that changes the colors of the screen according to the viewing angle, and it is only one-sided. When buying a TFT LCD display, first we need to check what kind of technology it is. If it is an IPS display, like the Riverdi IPS display line, then we do not need to worry about the grayscale inversion because all the viewing angles will be the same and all of them will be very high, like 80, 85, or 89 degrees. But if you buy a more common or older display technology type, like the TN (twisted nematic) display, you need to think where it will be used, because one viewing angle will be out. It may be sometimes confusing, and you need to be careful as most factories define viewing direction of the screen and mistake this with the greyscale inversion side.
We know already that TN (twisted nematic) displays, suffer from grayscale inversion, which means the display has one viewing side, where the image color suddenly changes. It is tricky, and you need to be careful. On the picture above there is a part of the LCD TFT specification of a TN (twisted nematic) display, that has grayscale inversion, and if we go to this table, we can see the viewing angles. They are defined at 70, 70, 60 and 70 degrees, that is the maximum viewing angle, at which the user can see the image. Normally we may think that 70 degrees is better, so we will choose left and right side to be 70 degrees, and then up and down, and if we do not know the grayscale inversion phenomena, we may put our user on the bottom side which is also 70 degrees. The viewing direction will be then like a 6 o’clock direction, so we call it a 6 o’clock display. But you need to be careful! Looking at the specification, we can see that this display was defined as a 12 o’clock display, so it is best for it to be seen from a 12 o’clock direction. But we can find that the 12 o’clock has a lower viewing angle – 60 degrees. What does it mean? It means that on this side there will be no grayscale inversion. If we go to 40, 50, 60 degrees and even a little bit more, probably we will still see the image properly. Maybe with lower contrast, but the colors will not change. If we go from the bottom, from a 6 o’clock direction where we have the grayscale inversion, after 70 degrees or lower we will see a sudden color change, and of course this is something we want to avoid.
We will talk now about the other TFT technologies, that allow us to have wider viewing angles and more vivid colors. The most basic technology for monochrome and TFT LCD displays is twisted nematic (TN). As we already know, this kind of displays have a problem with grayscale inversion. On one side we have a higher retardation and will not get a clear image. That is why we have other technologies like VA (Vertical Alignment), where the liquid crystal is differently organized, and another variation of the TFT technology – IPS which is In-Plane Switching. The VA and IPS LCD displays do not have a problem with the viewing angles, you can see a clear image from all sides.
Apart from the different organization of the liquid crystals, we also organize subpixels a little bit differently in a VA and IPS LCD displays. When we look closer at the TN display, we will just see the subpixels with color filters. If we look at the VA or IPS display they will have subpixels of subpixels. The subpixels are divided into smaller parts. In this way we can achieve even wider viewing angles and better colors for the user, but of course, it is more complicated and more expensive to do.
The picture above presents the TN display and grayscale inversion. For IPS or VA technology there is no such effect. The picture will be the same from all the sides we look so these technologies are popular where we need wide viewing angles, and TN is popular where we don’t need that, like in monitors. Other advantages of IPS LCD displays are they give accurate colors, and wide viewing angles. What is also important in practice, in our projects, is that the IPS LCD displays are less susceptible to mechanical force. When we apply mechanical force to the screen, and have an optically bonded touch screen, we push the display as well as squeeze the cells. When we have a TN display, every push on the cell changes the image suddenly, with the IPS LCD displays with in-plane switching, different liquid crystals organization, this effect is lesser. It is not completely removed but it is much less distinct. That is another reason IPS displays are very popular for smartphones, tablets, when we have the touchscreens usually optically bonded.
Now, let us look at the backlight types. As we see here, on the picture above, we have four distinct types of backlight possible. The most common, 95 or 99 per cent of the TFT LCD displays on the market are the transmissive LCD display type, where we need the backlight from the back. If you remember from our Monochrome LCD Displays lecture, for transmissive LCD displays you need the backlight to be always on. If you switch the backlight off, you will not see anything. The same as for monochrome LCD displays, but less popular for TFT displays, we have the transflective LCD display type. They are not popular because usually for transflective TFT displays, the colors lack in brightness, and the displays are not very practical to use. You can see the screen, but the application is limited. Some transflective LCD displays are used by military, in applications where power consumption is paramount; where you can switch the backlight off and you agree to have lower image quality but still see the image. Power consumption and saving energy is most important in some kind of applications and you can use transflective LCD displays there. The reflective type of LCD displays are almost never used in TFT. There is one technology called Low Power Reflective Displays (LPRD) that is used in TFT but it is not popular. Lastly, we have a variation of reflective displays with frontlight, where we add frontlight to the reflective display and have the image even without external light.
Just a few words about Low Power Reflective Displays (LPRD). This kind of display uses environmental light, ambient light to reflect, and produce some colors. The colors are not perfect, not perfectly clear, but this technology is becoming increasingly popular because it allows to have color displays in battery powered applications. For example, a smartwatch would be a case for that technology, or an electrical bike or scooter, where we can not only have a standard monochrome LCD display but also a TFT LCD color display without the backlight; we can see the image even in
strong sunlight and not need backlight at all. So, this kind of TFL LCD display technology is getting more and more popular when we have outdoor LCD displays and need a low power consumption.
On the picture above, we have some examples of how transmissive and reflective LCD displays work in the sunlight. If we have a simple image, like a black and white pattern, then on a transmissive LCD display, even with 1000 candela brightness, the image probably will be lower quality than for a reflective LCD display; if we have sunlight, we have very strong light reflections on the surface of the screen. We have talked about contrast in more detail in the lecture Sunlight Readable Displays. So, reflective LCD displays are a better solution for outdoor applications than transmissive LCD displays, where you need a really strong backlight, 1000 candela or more, to be really seen outdoors.
To show you how the backlight of LCD displays is built, we took the picture above. You can see the edge backlight there, where we have LEDs here on the small PCB on the edge, and we have a diffuser that distributes the light to the whole surface of LCD screen.
In addition to the backlight, we have something that is called a frontlight. It is similar to backlight, it also uses the LEDs to put the light into it, but the frontlight needs to be transparent as we have the display behind. On the example on the picture above we can see an e-paper display. The e-paper display is also a TFT display variation, but it is not LCD (liquid crystal), it is a different technology, but the back of the display is the same and it is reflective. The example you see is the Kindle 4 eBook reader. It uses an e-paper display and a frontlight as well, so you can read eBooks even during the night.
Displaying a custom image or graphic on a LCD display is a very useful task as displays are now a premium way of providing feedback to users on any project. With this functionality, we can build projects that display our own logo, or display images that help users better understand a particular task the project is performing, providing an all-round improved User Experience (UX) for your Arduino or ESP8266 based project. Today’s tutorial will focus on how you can display graphics on most Arduino compatible displays.
The procedure described in this tutorial works with all color displays supported by Adafruit’s GFX library and also works for displays supported by the TFTLCD library from Adafruit with little modification. Some of the displays on which this procedure works include:
For this tutorial, we will use the 2.8″ ILI9325 TFT Display which offers a resolution of 320 x 340 pixels and we will display a bitmap image of a car.
To demonstrate how things work, we will use the 2.8″ TFT Display. The 2.8″ TFT display comes as a shield which plugs directly into the Arduino UNO as shown in the image below.
Image2Code is an easy-to-use, small Java utility to convert images into a byte array that can be used as a bitmap on displays that are compatible with the Adafruit-GFX or Adafruit TFTLCD (with little modification) library.
To reduce the amount of code, and stress involved in displaying the graphics, we will use two wonderful libraries; The GFX library and the TFTLCD library from Adafruit.
As usual, we start writing the sketch by including the libraries required. For this procedure, we will use the TFTLCD library alone, since we are assuming you are using a display that is not supported by the GFX library.
The last section of the code is the drawBitmap function itself, as earlier mentioned, to use the drawbitmap() function with the Adafruit TFTLCD library, we need to copy the function’s code and paste into the Arduino sketch.