tft display vs capacitive display free sample

There are types of touch screen，such as resistive touch panel(RTP), capacitive touch panel (CTP), surface acoustic wave touch display, infrared touch screen. RTP and CTP are used more than others. Can you tell the difference between RTP and CTP? If not, you may want to read along.

Capacitive touchscreens, on the other hand, respond directly to the touch of your finger or an input device such as a stylus. On top of LCD panel, lies a thin layer of transparent electrodes. When a human finger touches the screen, some of the electrical charge travels from screen to user. The change of capacitance is then detected by sensors located at screen"s four corners, allowing controller determine the touched location.

Supporting of Multiple touches is a clear winner for capacitive touch screens (CTP). Thanks to smartphone and tablet, users are comfortable with using gesture on screen. And capacitive touch screen is what user is familiar with. In more specialized settings, such as multi-player gaming application, capacitiv e touch screens can support more than 10 inputs at a single time. Additionally, CTP needs no calibration and is highly accurate.

Resistive touch display cannot determine the location of a touch if more than one input is present. In terms of visibility, the film substrate commonly used as the top surface in resistive touch screens is less transmissive than glass. This leads to reduced brightness and a certain level of haze compared to touch screens with a top layer of glass. The film layer can also expand or contract based on temperature, which alters the distance between the two layers and affects touch accuracy. Additionally, the film substrates are susceptible to scratches and can start to wear away with repeated use, necessitating occasional recalibration or replacement over time.

Capacitive touch screens depend on variations in an electrical field to operate. While a passive stylus can activate this screen, a non-conductive tool like a pencil can"t. If cost is a top concern for a project, CTP may not align with budget limits. It is a more expensive technology than resistive screens, although it continues to grow more accessible in terms of price as the technology advances and improves.

A surface capacitive touchscreen uses a transparent layer of conductive film overlaid onto a glass sublayer. A protective layer is then applied to the conductive film. Voltage is applied to the electrodes on the four corners of the glass sublayer to generate a uniform electric field. When a conductor touches the screen, current flows from the electrodes to the conductor. The location of the conductor is then calculated based on the activity of the currents. Surface capacitive touchscreens are often used for large screen panels.

Projected capacitive touchscreens are extremely precise and quick responding and are typically found on smaller devices such as iPhones, iPod touches or iPads. Unlike the surface capacitive touchscreens, which use four electrodes and a transparent conductive film, the projected capacitive touchscreens use a vast amount of transparent electrodes arranged in a specific pattern and on two separate layers. When a conductor moves near the screen, the electrical field between the electrodes change and sensors can instantly identify the location on the screen. Projected capacitive touchscreens can accurately register multi-touch events.

The Transmissive polarizer is best used for displays that run with the backlight on all the time. This polarizer provides the brightest backlight possible. If you have a need for a bright backlight with lower power drain, transmissive is a good choice for this TFT LCD.

TheCapacitive touch panel is activated with anything containing an inductive load such as a finger or stylus. It allows for multi-touch options. When using the capacitive touch screen, the display needs a separate controller to interface with the touch panel. The display for capacitive touch is brighter since the touch panel is transparent.

Focus LCDs can provide many accessories to go with your display. If you would like to source a connector, cable, test jig or other accessory preassembled to your LCD (or just included in the package), our team will make sure you get the items you need.Get in touch with a team member today to accessorize your display!

Focus Display Solutions (aka: Focus LCDs) offers the original purchaser who has purchased a product from the FocusLCDs.com a limited warranty that the product (including accessories in the product"s package) will be free from defects in material or workmanship.

The Capacitive touch panel is activated with anything containing an inductive load such as a finger or stylus. It allows for multi-touch options. When using the capacitive touch screen, the display needs a separate controller to interface with the touch panel. The display for capacitive touch is brighter since the touch panel is transparent.

The Transmissive polarizer is best used for displays that run with the backlight on all the time. This polarizer provides the brightest backlight possible. If you have a need for a bright backlight with lower power drain, transmissive is a good choice for this TFT LCD display.

Focus LCDs can provide many accessories to go with your display. If you would like to source a connector, cable, test jig or other accessory preassembled to your LCD (or just included in the package), our team will make sure you get the items you need.Get in touch with a team member today to accessorize your display!

Focus Display Solutions (aka: Focus LCDs) offers the original purchaser who has purchased a product from the FocusLCDs.com a limited warranty that the product (including accessories in the product"s package) will be free from defects in material or workmanship.

Capacitive touch technology is increasingly used in user interfaces for a variety of devices. A capacitive touch display is created by attaching a capacitive layer on top of a glass panel substrate. These components are then covered with a protective outer layer, and the surface of the device will maintain a static charge. As a person’s finger or a stylus touches the surface, the charge will transfer from the panel surface to the device or finger. This allows the capacitive device to register the touch location.

Thin-film transistor (TFT) LCD capacitive touch screens have become a popular choice when compared to the other leading touch screen technology – resistive touch. While resistive touch screens have been around for a longer time and can be built at a lower cost, capacitive touch displays offer several significant advantages over other display technologies. In this post, we’ll explore what makes capacitive touch technology unique and how it performs across several parameters.

Capacitive touch technology offers excellent screen sensitivity when used with a finger or stylus. The surface of these devices will respond to varying degrees of pressure, as opposed to a resistive touch screen where firm and direct pressure must be used. A TFT LCD capacitive touch screen is also sensitive enough to be used only with fingers without the need for a stylus.

Capacitive stylus devices can be used for added precision and niche applications such as digital drawing. Another related benefit is support for multi-touch operation using multiple fingers simultaneously. This includes advanced gestures such as pinch-zoom that is a popular feature in many device applications today.

TFT LCD capacitive displays are known for their excellent optical quality. The glass substrate that sits below the electrode film transmits most of the available light to the surface resulting in crisp sharpness and display contrast. These screens are also known for outstanding color fidelity that supports the viewing of high-quality images, video, and software content. This also has a positive impact on the user experience when integrated into larger kiosks and interactive displays.

Capacitive touch devices are very stable, with little to no shift in the image being transferred to the screen. This is an important advantage over other display types, as image shift can get worse over time and require manual correction with other types of displays. A capacitive touch device, therefore, does not require the periodic calibrations that are commonly necessary with many older display technologies. Maintaining a stable image is an essential requirement in high-performance display applications, such as those found in the broadcasting and entertainment industries.

The glass substrate of a capacitive touch display is very strong, and the protective layer helps prevent scratches and other marks. Like most displays, a capacitive touch screen can crack if dropped or exposed to significant pressure. It should be noted that a cracked resistive touch screen most often ceases to operate, while a cracked capacitive device will usually maintain some functionality. This has made capacitive screens popular for commercial applications that are exposed to significant wear and tear.

The screen of a capacitive touch device can be completely sealed, preventing contaminants from entering the seams on the outer edges of the display. Preventing dust and condensation from getting inside the display is important for long-term use. This also makes a capacitive touch display easy to clean. Due to the ease of cleaning and other advantages, capacitive touch technology is often used for public digital displays in high-traffic areas.

The sensitivity of a capacitive touch display also contributes to excellent response times. As a user touches the screen at different locations, the surface can register these movements with a high degree of accuracy. A capacitive touch screen also performs very well when the user’s finger or stylus is dragged across the surface. This makes capacitive touch a preferred choice for graphic design and audio-visual applications.

One final advantage of capacitive touch technology is false touch rejection. A resistive display can be easily confused if multiple fingers touch the screen at the same time, making it unable to register accurate movement. The improved sensitivity of a capacitive display increases the ability of the surface to differentiate between multiple points of contact. In addition to enabling the custom gestures, sliding motions, and light touches mentioned above, this also eliminates the potential for a missed touchpoint.

Capacitive touch is a relatively new touchscreen technology that is having a significant impact on the display industry. With several advantages over competing design options, the use of TFT LCD capacitive touch technology is expected to grow significantly in the coming years. This will be an important trend for device manufactures, designers, and end-users to follow as an opportunity to improve product quality and performance.

This 10.1 inch TFT LCD display has a 1024x600 resolution screen with IPS technology, which delivers sunlight readable brightness, better color reproduction, better image consistency, and better optical characteristics at any angle. For extra protection, this 24-bit true color TFT also includes an EMI filter on the input power supply line. This 10.1" display is RoHS compliant with RGB interface, and has a capacitive touchscreen. This 10.1" IPS display has been designed with the same mechanical footprint and pinout and includes the same HX8282 driver IC as the TN display, making this a compatible replacement option for the TN models.

Enhance your user experience with capacitive or resistive touch screen technology. We’ll adjust the glass thickness or shape of the touch panel so it’s a perfect fit for your design.

Choose from a wide selection of interface options or talk to our experts to select the best one for your project. We can incorporate HDMI, USB, SPI, VGA and more into your display to achieve your design goals.

Equip your display with a custom cut cover glass to improve durability. Choose from a variety of cover glass thicknesses and get optical bonding to protect against moisture and debris.

Capacitive touch screen to help the emergence of iPhone has changed the world, its principle is to determine the specific location of one or more fingers by detecting the capacitive touch screen surface changes, including support for complex gestures, complete multi touch function, the reaction speed is extremely sensitive, for the user to bring extraordinary experience.

As digital signage supplier committed to digital signage solutions,and founded in 2004. We are major in produce Digital signage player and Digital signage displays,to match the requirement of our customers in the human-computer interface applications,advertising display and customer customized display equipment;

Spice up your Arduino project with a beautiful large touchscreen display shield with built in microSD card connection. This TFT display is big (5" diagonal) bright (18 white-LED backlight) and colorful 800x480 pixels with individual pixel control. As a bonus, this display has a capacitive touch panel attached on screen by default.

This display shield has a controller built into it with RAM buffering, so that almost no work is done by the microcontroller. You can connect more sensors, buttons and LEDs.

With the integration of Bridgetek’s next generation EVE3 BT815/BT816 Embedded Video Engine IC, Matrix Orbital EVE3 SPI TFT"s deliver clean, crisp, full color TFT screens for interactive menus, graphing, graphics and even video.

Point of Sales Machines, Multi-function Printers, Instrumentation, Home Security Systems, Graphic touch pad – remote, dial pad, Tele/Video Conference Systems, Phones and Switchboards, Medical Appliances, Breathalyzers, Gas chromatographs, Power meter, Home appliance devices, Set-top box, Thermostats, Sprinkler system displays, GPS / Satnav, Vending Machine Control Panels, Elevator Controls, and many more....

TFT (Thin Film Transistor) LCD (Liquid Crystal Display) dominates the world flat panel display market now. Thanks for its low cost, sharp colors, acceptable view angles, low power consumption, manufacturing friendly design, slim physical structure etc., it has driven CRT(Cathode-Ray Tube) VFD ( Vacuum Fluorescent Display) out of market, squeezed LED (Light Emitting Diode) displays only to large size display area. TFT LCD displays find wide applications in TV, computer monitors, medical, appliance, automotive, kiosk, POS terminals, low end mobile phones, marine, aerospace, industrial meters, smart homes, handheld devices, video game systems, projectors, consumer electronic products, advertisement etc. For more information about TFT displays, please visit our knowledge base.

There a lot of considerations for how to choose a most suitable TFT LCD display module for your application. Please find the check list below to see if you can find a right fit.

It is the start point for every project. There aretwo dimensions to consider: outside dimension (width, height, thickness) and AA (active area or pixel area). Orient Display’s standard product line ranges from 1.0” to 32”. Our OLED size can go down to 0.66” which fit for wearable devices.

Resolution will decide the clearance. Nobody likes to see a display showing pixel clearly. That is the reason for better resolution, going from QVGA, VGA to HD, FHD, 4K, 8K. But higher resolution means higher cost, power consumption, memory size, data transfer speed etc. Orient Display offers low resolution of 128×128 to HD, FHD, we are working on providing 4K for our customers. For full list of resolution available, please see Introduction: LCD Resolution

TFT screen brightness selection is very important. You don’t want to be frustrated by LCD image washout under bright light or you drain the battery too fast by selecting a super brightness LCD but will be used indoor only. There are general guidance listed in the table below.

Orient Display offers standard brightness, medium brightness , high brightness, and high end sunlight readable IPS TFT LCD display products for our customers to choose from.

If the budget is tight, TN type TFT LCD can be chosen but there is viewing angle selection of either 6 o’clock or 12 o’clock. Gray scale inversion needs to be taken of carefully. If a high-end product is designed, you can pay premium to select IPS TFT LCD which doesn’t have the viewing angle issue.

It is similar to viewing angle selection, TN type TFT LCD has lower contrast but lower cost, while IPS TFT LCD has much high contrast but normally with higher cost. Orient Display provides both selections.

Normal TFT LCD displays provide wide enoughtemperature range for most of the applications. -20 to 70oC. But there are some (always) outdoor applications like -30 to 80oC or even wider, special liquid crystal fluid has to be used. Heater is needed for operating temperature requirement of -40oC. Normally, storage temperature is not an issue, many of Orient Display standard TFT display can handle -40 to 85oC, if you have any questions, feel free to contact our engineers for details.

Power consideration can be critical in some hand-held devices. For a TFT LCD display module, backlight normally consumes more power than other part of the display. Dimming or totally shutdown backlight technology has to be used when not in use. For some extreme power sensitive application, sleep mode or even using memory on controller consideration has to be in design. Feel free to contact our engineers for details.

Genetic Interfaces: Those are the interfaces which display or touch controller manufacturers provide, including parallel, MCU, SPI(,Serial Peripheral Interface), I2C, RGB (Red Green Blue), MIPI (Mobile Industry Processor Interface), LVDS (Low-Voltage Differential Signaling), eDP ( Embedded DisplayPort) etc. Orient Display has technologies to make the above interface exchangeable.

High Level Interfaces: Orient Display has technologies to make more advanced interfaces which are more convenient to non-display engineers, such as RS232, RS485, USB, VGA, HDMI etc. more information can be found in our serious products. TFT modules, Arduino TFT display, Raspberry Pi TFT display, Control Board.

Touch panels have been a much better human machine interface which become widely popular. Orient Display has been investing heavy for capacitive touch screen sensor manufacturing capacity. Now, Orient Display factory is No.1 in the world for automotive capacitive touch screen which took around 18% market share in the world automotive market.

Based on the above three types of touch panel technology, Orient Display can also add different kinds of features like different material glove touch, water environment touch, salt water environment touch, hover touch, 3D (force) touch, haptic touch etc. Orient Display can also provide from very low cost fixed area button touch, single (one) finger touch, double finger (one finger+ one gesture) touch, 5 finger touch, 10 points touch or even 16 points touch

Considering the different shapes of the touch surface requirements, Orient Display can produce different shapes of 2D touch panel (rectangle, round, octagon etc.), or 2.5D touch screen (round edge and flat surface) or 3D (totally curved surface) touch panel.

Considering different strength requirements, Orient Display can provide low cost chemical tampered soda-lime glass, Asahi (AGC) Dragontrail glass and Corning high end Gorilla glass. With different thickness requirement, Orient Display can provide the thinnest 0.5mm OGS touch panel, to thickness more than 10mm tempered glass to prevent vandalizing, or different kinds of plastic touch panel to provide glass piece free (fear) or flexible substrates need.

Of course, Orient Display can also offer traditional RTP (Resistive Touch Panel) of 4-wire, 5-wire, 8-wire through our partners, which Orient Display can do integration to resistive touch screen displays.

If you can’t find a very suitable TFT LCD Display in our product line, don’t be discouraged. The products listed on our website is only small part of standard products. We have thousands of standard products in our database, feel free to contact our engineers for details.

If you like to have a special display, Orient Display is always flexible to do partial custom solution. For example, to modify the FPC to different length or shape, or use as fewer pinouts as possible, or design an ultra-bright LCD display, or a cover lens with your company logo on it, or design an extreme low power or low cost TFT display etc. our engineers will help you to achieve the goals. The NER cost can start from hundreds of dollars to Thousands. In rare case, it can be tens of thousands of dollars.

A fully custom TFT LCD panel can have very high NRE cost. Depending on the size of the display, quantity and which generation production line to be used. The tooling cost can start from $100,000 to over $1M.

1. Professional Manufacturer in LCD Display: Hongxian Technology Co., Ltd. specializes in customizing high-end LCD display, which is widely used in military industry, security, vehicle audio-visual, medical, reverse rearview mirror, industrial control equipment, smart home, visual doorbell, building elevator advertising, SIP telephone and so on.2. Accept Customization Order:We aim to provide customers with great product solutions. In order to better serve our valuable customers, we accept the customization order of the driver board, touch screen of AV, VGA, MCU, etc.

Touchscreens have changed the way people expect to interact with their devices. When it comes to smartphones and tablets, touch is the way to go. Even handheld game consoles, laptops, and car navigation systems are moving towards touch. Manufacturers of these devices need to give their respective consumers the responsiveness these consumers are looking for. Selecting the right TFT-LCD display to use for different devices is important.

For touch-sensitive displays, two types of technologies are used: resistive and capacitive. The main difference is in how they respond to touch. Mobile phone comparison site Omio indicates that resistive technology is more accurate but capacitive technology is more responsive.

Capacitive touchscreens, on the other hand, offer more responsiveness with better optical clarity and multi-touch performance. They detect more complex finger gestures. These qualities are shown to be more important for general interaction so it’s more dominant in smartphones and tablets, as well as in other devices with small to medium screen sizes.

As you can see, capacitive screens get general usage while resistive screens cater to more specific applications. With this, TFT-LCD module manufacturers, like Microtips Technology, focus on continuously improving capacitive screen technology.

Electronic Design states that many technological advances can be used to integrate touch sensors directly into the display. In some, manufacturers stack-up the touch sensors and integrate the controller with the display driver ICs. These advances allowed thinner and smarter capacitive touchscreens – a trend that you see in many devices today. For example, Windows phones originally worked exclusively with resistive touchscreen technology but later on moved over to capacitive. If the continuous development of capacitive touchscreen technology becomes successful, these screens may soon have abilities they don’t possess at the moment, such as hover support, non-finger support, and many more.

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.

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.

Touchscreen displays are everywhere! Phones, tablets, self-serve kiosks, bank machines and thousands of other devices we interact with make use of touchscreen displays to provide an intuitive user interface.

Today we will learn how touchscreens work, and how to use a common inexpensive resistive touchscreen shield for the Arduino.  Future videos and articles will cover capacitive touchscreens, as well as a touchscreen HAT for the Raspberry Pi.

Eric A Johnson, a researcher at the Royal Radar Establishment in Malvern UK is credited for describing and then prototyping the first practical touchscreen. HIs device was a capacitive touchscreen, and it’s first commercial use was on air traffic control screens. However, the touchscreens used then were not transparent, instead, they were mounted on the frame of the CRT display.

In 1972, a group at the University of Illinois filed for a patent on an optical touchscreen. This device used a 16×16 array of LEDs and phototransistors, mounted on a frame around a CRT display. Placing your finger, or another solid object, on the screen would break two of the light beams, this was used to determine the position and respond accordingly.

In 1982 theUniversity of Toronto’sInput Research Group developed the first multi-touch touchscreen, a screen that could interpret more than one touch at the same time.  The original device used a video camera behind a frosted piece of glass. Three years later the same group developed a multi-touch tablet that used a capacitive touchscreen instead.

The first commercial product to use a touchscreen was a point-of-sale terminal developed by Atari and displayed at the 1986 COMDEX expo in Las Vegas. The next year Casio launched theCasio PB-1000 pocket computerwith a touchscreen consisting of a simple 4×4 matrix.

LG created the world’s first capacitive touchscreen phone, theLG Pradaused a capacitive touchscreen and was released in early 2007. A few weeks later Apple released its first iPhone.

Most early touchscreen devices were resistive, as this technology is generally less expensive than capacitive screens. However, nowadays capacitive screens are more common, being used in the majority of smartphones and tablets.

Although they were invented after capacitive touchscreens, resistive touchscreens are probably the most common type used by hobbyists. The reason for that is the price and performance, resistive touchscreens are cheaper than capacitive ones and they are generally more accurate.

This is the most inexpensive method of designing a resistive touchscreen. The touchscreen display that we will be working with today uses this arrangement.

Capacitive touchscreens are actually older technology than resistive displays.  They are commonly used in phones and tablets, so you’re probably familiar with them.

The capacitive touchscreen makes use of the conductivity of the human body. The touchscreen itself consists of a glass plate that has been treated with a conductive material.

The surface capacitive touchscreen is the most inexpensive design, so it is widely used. It consists of four electrodes placed at each corner of the touchscreen, which maintain a level voltage over the entire conductive layer.

This is a more advanced touchscreen technique. In a projected capacitive touchscreen transparent electrodes are placed along the protective glass coating and are arranged in a matrix.

You can also just use the shield as an LCD display and ignore the two other components, however, if you intend on doing that it would be cheaper just to buy an LCD display without any touchscreen features.

This is a TFT orThin Film Transistordevice that uses liquid crystals to produce a display.  These displays can produce a large number of colors with a pretty decent resolution.

You do need to be looking directly at the display for best color accuracy, as most of these inexpensive LCD displays suffer from distortion and “parallax error” when viewed from the side. But as the most common application for a device like this is as a User Interface (UI) this shouldn’t be a problem.

The microSD card socket is a convenience, it’s normally used for holding images for the display but it can also be used for program storage.  This can be handy for holding things like calibration settings and favorite selections.

The last paragraph regarding the microSD card may make you think that an Arduino Uno is the best choice for the Touchscreen Display Shield.  And it you require the microSD card then it probably is a good choice.

As there are three devices on the shield you will need libraries for each of the ones you want to use.  TheSD Libraryis already installed in your Arduino IDE, so you will just need libraries for the display and touchscreen.

This useful resource contains code, libraries and datasheets for a wealth of LCD displays, both touchscreen and non-touchscreen. You’ll also find code for some common OLED displays as well.

I ran my touchscreen through all of the code samples I obtained from the LCD Wiki. It’s an interesting exercise, and by examining the sketch for each demo you can learn a lot about programming the display.

This test does not make use of any of the extra libraries, it drives the LCD directly. It is only a test of the LCD display, it does not make use of the touchscreen membrane.

This example does use the custom libraries, and is a very good way to learn how to use them.  You’ll note that theLCDWIKI_GUI.hlibrary is loaded, which is the graphics library for the LCD display.

This sketch uses a number of functions from theLCDWIKI_GUI.hlibrary, along with some custom functions to draw geometric shapes. It then displays a cycle of graphs, shapes, and patterns on the LCD display.

One way in which this sketch differs is that most of the graphics routines are executed in the Setup function, so they only run once. The loop then displays some text with a selection of colors and fonts. The orientation is changed as it cycles through the loop.

This example makes use of a second file that contains fonts. The Display Scroll sketch illustrates a number of different methods of scrolling characters, in different fonts, colors and even languages.

One interesting thing about this test is that it illustrates how to display text in different “aspects”, Portrait and Landscape, Right side up and Reversed.

Unlike the previous examples that put the text in with a number of graphics, this example is a pretty simple one with just a block of text in different sizes and colors.  This makes it very simple to understand how the text is positioned on the display.

The result of running the sketch is the display screen fills with rows of hexadecimal values while the background alternates between blue and black and the orientation (or “aspect”) changes.  If you stand back to see the “big picture” you’ll note that the color values form “number patterns”.

The Display Phone Call sketch draws a mockup telephone keypad. Pressing one of the keys will display the result on a line of text at the top.  There is also a key to delete your entries, as well as ones to send and disconnect the call – the latter two are “dummy” functions of course as it’s only a demo.

As its name would imply, this sketch displays a bitmap image on the display. The images need to be placed onto the root of a microSD card, which in turn is plugged into the socket on the display shield.

The images will show off the display resolution, which is reasonably impressive. You’ll also note that to see them at their best, you need to be directly in front of the display, viewing the display at an angle causes the display to distort colors.

This example draws some small “switches” on the display. The switches are active and respond to touch.  There are slide switches, a push button, some radio buttons and some text-based expandable menus to test with.

After calibration, the sketch will display a number of calibration values for the resistive touchscreen. These values can be used in your future sketches to make the touchscreen more accurate.

The digital I/O connector at the back of the Mega is still accessible even when the touchscreen display shield is installed, so I used three of those connections for the LEDs. I hooked up each LED anode through a 220-ohm dropping resistor and connected them as follows:

The sketch is based upon the telephone keypad sketch. I modified it to eliminate the other functions and just display three buttons.  Then I added code to toggle the LEDs.

TheAdafruit GFX Libraryis a comprehensive graphics library that can be used in a variety of display applications.  It is a “core library”, meaning that it is called by other Adafruit libraries.

TheAdafruit TFTLCD Libraryis used. It uses the previous library to provide an easy method of drawing on the LCD display.  It works with LCD displays that use driver chips like the ILI9325 and ILI9328.

TheMCUFRIEND_kbvlibrary is also included in the software you obtained for your display shield. It takes care of supplying the correct hardware information for your display shield to the other libraries.

Next, we define some touchscreen parameters. You can ‘fine-tune” your code here by using parameters from your own display, which you can obtain from the Calibration Sketch we ran from the sample code.  Otherwise, just use the values here and you should be fine.

Next, we reset the display and try to identify it. This will run through a list of display chip drivers in the MCUFRIEND_kbv library and will attempt to select the correct one.

Now, still in the Setup, we set up the LCD display rotation and fill the background in black. Next step is to draw our buttons. Once we are done that the Setup is finished, and our screen should be displaying the three buttons on a black background.

We then need to reset the pin modes for two of the touchscreen pins back to outputs. This is done as these pins get shared with other LCD display functions and get set as inputs temporarily.

Touchscreen interfaces are used in a number of products, and now you can design your own devices using them. They can really make for an intuitive and advanced display and will give your project a very professional “look and feel” if done correctly.

This is not the only time we will look at touchscreen displays. Next time we’ll examine a capacitive touchscreen and we’ll explore the Adafruit Graphics libraries further to create some very fancy displays with controls and indicators.