tft display flickering made in china

They expose to various environments, especially now that COVID-19 spreading around the world. So it"s impossible to keep a screen clean all the time. When you are going to clean an LCD display，do you have the right steps in mind？Maybe what you"ve been doing is not right！

@pryankster I thought I may be able to help by trying a very similar looking display that I have never used before. This proved interesting as the only driver that worked was the S6D02A1_DRIVER. I have not used one of these displays since migrating projects to the ESP8266 and ESP32 so it was interesting to see how fast typical sketch screens get drawn on a smaller display. I also found this controller seems to run fine at 40MHz, but I have not expensively tested it:

I"ve got a chinese 1.44" TFT - very similar to AdaFruit"s. In fact, I think it"s the same and the Adafruit ST7735 library works great with it right away.

But I have a problem: the screen is too slow to update and flickers too much. Even if I only update it once per second the flickering is still very noticeable and prevents me from achieving visual smoothness, which I will need for my project.

Note that I have set up a timer using the TimerOne library, it"s currently set for 100 ms = 10 FPS. But as I said, the code speed is not the problem, I can get higher FPS. It"s flickering that"s the problem.

TFT LCD display flickering problem origins from vary sources. Topway"s technical support team worked with clients solved another screen flickering issue.

We have this customer, who uses Topway TFT LCD display on the new Programmable Electronic Loads project. An electronic load is a instrument that voltage and sinks current. Programmable electronic load, unlike passive resistive load, offers variety of voltage/current ranges and operates under multiple modes. It is an indispensable tool for functional test on batteries, solar cells, wind generator and other power sources.

During testing, customer observed serious screen flickering problem when the instrument operated in -10℃ environment. And the TFT LCD screen returned to normal after one minute in operation.

Topway"s support engineers joint customer"s project team immediately. The engineer group drew out a game plan to tackle the TFT LCD flickering problem.

Topway TFT LCD displays are designed to work in -20℃ to 70℃ environment. Stand-alone TFT LCD screen was lit up and put into below -10℃ room for 30 minutes. There was no flickering symptom observed. So the TFT LCD itself is not the culprit.

The engineers hooked up a monitor device on LCD screen"s power supply, saw no fluctuation in term of voltage and current. But LCD screen flickering persisted.

After analyzing Phase Locked Loop synthesizer output signal, engineers realized the frequency was set too high. Adjusting that solved the TFT LCD"s flickering issue.

Topway support team successfully help customer resolve the TFT screen issue. And the programmable electronic load device passed all the necessary tests.

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.

Troubleshooting CRTs versus LCDs begins with similar steps, but diverges due to the differing natures of the two display types. The first troubleshooting steps are similar for either display type: power down the system and display and then power them back up; make sure the power cable is connected and that the outlet has power; verify that the signal cable is connected firmly to both video adapter and display and that there are no bent pins; verify that the video adapter is configured properly for the display; try the problem display on a known-good system, or try a known-good display on the problem system; and so on. Once you"ve tried the "obvious" troubleshooting steps, if the problem persists, the next step you take depends on the type of display. The following sections cover basic troubleshooting for CRTs and LCDs.

CRTs seldom fail outright without obvious signs, such as a loud snap or a strong odor of burning electrical components. Most CRT problems are really problems with the power, video adapter, cable, or hardware/software settings. To eliminate the CRT as a possible cause, connect the suspect CRT to a known-good system, or connect a known-good display to the suspect system. It is worth noting, that older CRTs eventually wear out, and starts dimming. Common signs of a weak CRT are a dim picture, dysfunctional brightness and/or color controls, image smearing at high brightness, and in color CRTs, a tint towards a single color (Red Green Blue)

CRTs contain multiple filaments, which can be broken, or gas may have leaked into the vacuum inside the CRT. CRTs damaged this way are unrepairable without specialist equipment. With the display open. check if all three filaments are glowing bright orange. Excessive redness or purple arcing signifies gas has leaked in. There may also be an internal short inside the CRT, which is also unfixable without specialist equipment.

If you have ACPI or APM power management enabled, it may be causing the problem. Some systems simply refuse to wake up once power management puts them to sleep. We have seen such systems survive a hardware reset without restoring power to the CRT. To verify this problem, turn off power to the system and CRT and then turn them back on. If the CRT then displays an image, check the power management settings in your BIOS and operating system and disable them if necessary.

The horizontal and/or vertical deflection system has failed. The CRT tube itself is fine, but the circuitry driving the tube has failed. Replace the display.

There are two likely causes. First, you may be driving the CRT beyond its design limits. Some CRTs display a usable image at resolutions and/or refresh rates higher than they are designed to use, but under such abuse the expected life of the CRT is shortened dramatically, perhaps to minutes. To correct this problem, change video settings to values that are within the CRT"s design specifications. Second, the power receptacle may be supplying voltage lower than the CRT requires. To correct this problem, connect the CRT to a different circuit or to a UPS or power conditioner that supplies standard voltage regardless of input voltage.

The video card settings are likely outside the range supported by the CRT, particularly if you have just installed the CRT or have just changed video settings. To verify this, restart the system in Safe Mode (press F8 during boot to display the Windows boot menu and choose Safe Mode). If the system displays a VGA image properly, change your display settings to something supported by the CRT.

Most modern CRTs can display signals at many different scan frequencies, but this doesn"t mean that the CRT will necessarily automatically display different signals full-screen and properly aligned. Use the CRT controls to adjust the size and alignment of the image.

The CRT may need to be degaussed. A CRT that sits in one position for months or years can be affected even by the earth"s very weak magnetic field, causing distortion and other display problems. Exposing a CRT to a strong magnetic field, such as unshielded speakers, can cause more extreme image problems. Many modern CRTs degauss themselves automatically each time you cycle the power, but some have a manual degauss button that you must remember to use. If your CRT has a manual degauss button, use it every month or two. The degaussing circuitry in some CRTs has limited power. We have seen CRTs that were accidentally exposed to strong magnetic fields, resulting in a badly distorted image. Built-in degaussing did little or nothing. In that case, you can sometimes fix the problem by using a separate degaussing coil, available at RadioShack and similar stores for a few dollars. We have, however, seen CRTs that were so badly "magnet burned" that even a standalone degaussing coil could not completely eliminate the problem. The moral is to keep magnets away from your CRT, including those in speakers that are not video-shielded.

An incorrect yoke may have been attached to the CRT. Unless you have a lot of spare time on your hands, this is usually not worth fixing. Replace the display.

If your LCD displays no image at all and you are certain that it is receiving power and video signal, first adjust the brightness and contrast settings to higher values. If that doesn"t work, turn off the system and LCD, disconnect the LCD signal cable from the computer, and turn on the LCD by itself. It should display some sort of initialization screen, if only perhaps a "No video signal" message. If nothing lights up and no message is displayed, contact technical support for your LCD manufacturer. If your LCD supports multiple inputs, you may need to press a button to cycle through the inputs and set it to the correct one.

First, try setting the optimal refresh rate as described above. If that doesn"t solve the problem and you are using an analog interface, there are several possible causes, most of which are due to poor synchronization between the video adapter clock and the display clock, or to phase problems. If your LCD has an auto-adjust, auto-setup, or auto-synchronize option, try using that first. If not, try adjusting the phase and/or clock settings manually until you have a usable image. If you are using an extension or longer than standard video cable, try connecting the standard video cable that was supplied with the display. Long analog video cables exacerbate sync problems. Also, if you are using a KVM switch, particularly a manual model, try instead connecting the LCD directly to the video adapter. Many LCDs are difficult or impossible to synchronize if you use a KVM switch. If you are unable to achieve proper synchronization, try connecting the LCD to a different computer. If you are unable to achieve synchronization on the second computer, the LCD may be defective. Finally, note that some models of video adapter simply don"t function well with some models of LCD.

If the screen is displaying a full, stable image, but that image is of poor quality, first verify that the display is not connected through a KVM switch or using an extension cable. If so, connect the display directly to the video adapter using the standard cable. If that is already the case, adjust the brightness, contrast, and focus controls. If you are unable to get a proper image using these controls, the problem is most likely a clock or phase mismatch, which you can cure by taking the steps described in the preceding item.

Your video card is supplying a video signal at a bandwidth that is above or below the ability of your LCD to display. Reset your video parameters to be within the range supported by the LCD. If necessary, temporarily connect a different display or start Windows in Safe Mode and choose standard VGA in order to change video settings.

This occurs when you run an LCD at other than its native resolution. For example, if you have a 19" LCD with native 1280x1024 resolution but have your display adapter set to 1024x768, your LCD attempts to display those 1024x768 pixels at full screen size, which physically corresponds to 1280x1024 pixels. The pixel extrapolation needed to fill the screen with the smaller image results in artifacts such as blocky or poorly rendered text, jaggy lines, and so on. Either set your video adapter to display the native resolution of the LCD, or set your LCD to display the lower-resolution image without stretching the display (a feature sometimes referred to as display expansion), so that pixels are displayed 1:1, which results in the lower resolution using less than the entire screen.

This is a characteristic of LCDs, particularly older and inexpensive models, caused by defective pixels. Manufacturers set a threshold number below which they consider a display acceptable. That number varies with the manufacturer, the model, and the size of the display, but is typically in the range of 5 to 10 pixels. (Better LCDs nowadays usually have zero dead pixels.) Nothing can be done to fix defective pixels. Manufacturers will not replace LCDs under warranty unless the number of defective pixels exceeds the threshold number.

Some people claim that leaving the unit powered off for a day or two will "erase" a persistent after-image. Others suggest leaving a neutral gray screen (like the one used for phase adjustment) up on the screen to "equalize" the display. I dunno. FWIW, I"ve seen this problem on older Samsung panels but never on the Sony or NEC/LaCie panels I use.

Again, this is a characteristic of LCDs, particularly older and inexpensive models. The after-image occurs when the display has had the same image in one place for a long time. The after-image may persist even after you turn the display off.

Use the brightness control to increase image brightness. If you have set brightness to maximum and the image is still too dim, contact the display manufacturer. The CCRTs used to backlight the screen have a finite lifetime and may begin to dim as they near the end of their life.

If one or more horizontal and/or vertical lines appear on the display, first power-reset the computer and display. If the lines persist, run the auto-setup function of your display. If that does not solve the problem, power the system and display down, remove the video cable, and verify that the video plugs and jacks on both computer and display ends do not have broken or bent pins. Even if all appears correct, try a different video cable. If the problem persists, contact the display manufacturer.

Because every point on the TFT LCD screen maintains that color and brightness after receiving the signal, it glows at a constant rate, rather than constantly refreshing the bright spots as the cathode ray tube display (CRT) does. As a result, the TFT LCD is of high quality and does not flicker, reducing eye fatigue to a very low level.

For displays of the same size, the visual area of the TFT LCD screen is larger. The visible area of the TFT LCD is the same as its diagonal size. Cathode ray tube display screen picture tube front panel around an inch or so of the border can not be used for display.

The original LCD screen is usually used in electronic watches and calculators because it is unable to display delicate characters. With the continuous development and progress of liquid crystal display technology, character display begins to be exquisite, but also supports the basic color display, and gradually used in liquid crystal TV, camera liquid crystal display.

The subsequent DSTN and TFT were widely made into liquid crystal display devices in computers, and DSTN LCD screens were used in early notebooks. TFT is used not only on laptops (most laptops now use TFT displays), but also on mainstream desktop displays.

The display material of the traditional display screen is phosphor, which is shown by the impact of the electron beam on the phosphor. The electron beam produces strong electromagnetic radiation in the moment it hits the phosphor. Although there are many display products in dealing with the radiation problem more effectively, as far as possible to reduce the amount of radiation to a very low, but to completely eliminate it is difficult. Relatively speaking, the TFT LCD screen has an innate advantage in preventing radiation because it does not exist at all.

In the aspect of electromagnetic wave prevention, TFT LCD screen also has its own unique advantages. It uses strict sealing technology to seal a small number of electromagnetic waves from the driving circuit in the display, while ordinary displays in order to emit heat. The internal circuit must be in contact with the air as much as possible so that the electromagnetic waves generated by the internal circuit "leak" outward in large quantities.

TFT LCD screens are digital and do not use analog interfaces like cathode ray tube color displays. In other words, with the TFT LCD, the graphics card no longer needs to convert the digital signal into an analog signal and output it as usual. In theory, this would make the color more accurate and perfect.

A traditional cathode ray tube display is always dragged behind a bulky ray tube. The TFT LCD breaks through this limit and gives a whole new feel. The traditional display screen emits electron beam to the screen, so the neck of the picture tube can not be very short, when the screen increases, it is necessary to increase the size of the whole display.

On the other hand, the TFT LCD screen controls the liquid crystal molecular state through the electrode on the display screen to achieve the display purpose. Even if the screen is enlarged, its volume will not increase in direct proportion, and its weight is much lighter than the traditional display with the same display area.

Compared with the traditional display screen, the TFT LCD screen starts with a pure flat glass panel, and its display effect is flat at right angles, giving people a refreshing feeling. And it is easier for LCD to achieve high resolution on a small screen. For example, a 17-inch LCD can achieve a good resolution of 1280 × 1024. On the other hand, the effect of using a resolution of more than 1280 × 1024 on an 18-inch CRT color display is not entirely satisfactory.

The traditional display screen is composed of many circuits. When these circuits drive the cathode ray picture tube, they need to consume a lot of power, and with the continuous increase of the volume, the power consumed by the internal circuit will certainly increase. In contrast, the power consumption of TFT LCD is mainly consumed by its internal electrode and driver IC, so the power consumption is much smaller than that of traditional display.

The reason for LCD Display flashing screen: shielding coil; Signal interference; Hardware; Refresh frequency setting; Monitor time is too long; Too high...

This screen is located on this site. Since overlays already exist for this display in the /boot/overlays directory, it will be supported with a simple configuration.

If you are using the GPIO controllers, you can instead change the GPIO pin configuration by using pin 4 or 5 to set the pin used, avoiding the pins used by your display. See here for details.

This 2.8" screen works well but may be too small and too expensive (35€) as far as Chinese clones are concerned. So let"s configure a 3.2" TFT screen from Waveshare that can be found on Banggood for less than 15€.

The screen is the following: a 3.2" TFT LCD touchscreen display module for the Raspberry Pi B+, B, A+. Its resolution is the same as the 2.8": 320x240. It is in fact a Waveshare screen.

Get the files waveshare35a-overlay.dtb and waveshare32b-overlay.dtb for the WaveShare 3.2" 320x240 display and the WaveShare 3.5" 320x480 display respectively. For the new version 4.4 kernels, we need to rename the dtb files to dtbo files to match the new overlay tree name. Rename waveshare35a-overlay.dtb to waveshare35a.dtbo and waveshare32b-overlay.dtb to waveshare32b.dtbo and copy them to the /boot/overlays directory.

If you are using the GPIO controllers, you can instead change the GPIO pin configuration by using pin 4 or 5 to set the pin used, avoiding the pins used by your display. See here for details.

This display cannot be used for arcade games with Recalbox. The SPI bus does not have enough bandwidth to handle this higher resolution of 480x320. If you increase the bus speed, the display becomes unstable (colors, flickering). During my tests, I could only get 20-25 FPS. This display is usable with an X server with a slow frame rate but not in arcade mode which requires a higher frame rate.

As described on this site, it is not recommended to use this screen for gaming. With twice as many pixels to push on the screen, the PiTFT 3.5" is significantly slower than its more compact brothers and we strongly advise against it for games. Now you know!

If you are using the GPIO controllers, you can instead change the GPIO pin configuration by using pin 4 or 5 to set the pin used, avoiding the pins used by your display. See here for details.

With the large influx of new displays into the market boasting ‘3D support’, we thought we would produce an article which outlines some of the key technologies being used, where they differ and how they work. We will look at the two main techniques being used today, those being active shutter and passive polarization technologies. We will also discuss the trends in desktop displays from a 3D point of view as well as looking at the other aspects being developed to support 3D, such as panel technology.

To begin with an explanation, a modern 3D display / monitor is capable of conveying a stereoscopic perception of 3D depth to the viewer. The basic requirement is to present offset images that are displayed separately to the left and right eye. Both of these 2D offset images are then combined in the brain to give the perception of 3D depth. Although the term “3D” is ubiquitously used, it is important to note that the presentation of dual 2D images is distinctly different from displaying an image in 3 full dimensions. The most notable difference is that the observer is lacking any freedom of head movement and freedom to increase information about the 3-dimensional objects being displayed. Holographic displays do not have this limitation, so the term “3D display” fits accurately for such technology. In modern displays the term 3D is actually an overstatement of capability and is referring to dual 2D images as being “3D”. The accurate term “stereoscopic” is more cumbersome than the common misnomer “3D”, which has been entrenched after many decades of unquestioned misuse.

Passive Stereo 3D – special films are applied to the screen instead to produce the 3D effect, and polarized glasses separate the images for the left and right eye. This is the standard solution for delivering stereo 3D to audiences of more than a small group of people and is becoming increasingly popular in desktop displays as well.

A great deal of innovation in display technologies related to Stereo 3D has taken place in the last few years. The re-use of existing terms and the introduction of conversions for formats and approaches have led to some confusion of how terms in the different stages are used. Particularly with the variety of display types, the image pairs may be prepared in some format but the display may treat and present them differently, hence the need to separate a discussion of these stages:

Once Stereo 3D image pairs have been created by the source, they have to be prepared for the stereo display device that is being used by the user and transmitted to that display over a display interface in a format that the display can interpret and use. Dual-link DVI, HDMI 1.4a and DisplayPort all have the ability to transmit stereo images although in some cases the resolution is limited. Where active shutter glasses are being used, a synchronization signal for these is also generated and transmitted

The presentation of the image pairs is the responsibility of the display device. Again, there has been a great deal of innovation in how this is achieved, but the main approaches, as briefly discussed before are as follows:

Active, frame sequential, display with shutter glasses – As discussed earlier, the display presents left and right eyes in sequence and shutter glasses are synchronized with that display.

Passive (polarizing) display and polarized glasses – As discussed earlier, the use of polarizing or wavelength-filtering glasses exist. Passive displays come in a few forms. Some passive displays are created using dual display technology. To achieve this, two displays present images with different polarization, and they are typically aligned with a half-mirror that permits the light from both displays to be presented together to the user’s eyes. This approach allows for full brightness and full resolution stereo to be presented to the user. Far more common is the single display method. Here typically a polarizing filter or film is added to the front glass of a display, carefully aligned to rows or columns of pixels (or some checkerboard pattern). Left and right images of a stereo pair are aligned to the corresponding pixels. This approach is attractive because of the lower cost of the display (than dual display).

A great deal of innovation has been taking place in Stereo 3D display technologies, leading to a fairly complex set of options for driving these displays, and a need for the user to understand the display type and select the corresponding preparation and transmission method. With the increasing popularity of Stereo 3D content for consumers (e.g. Blu-ray 3D, transmission to the home from various cable and satellite providers), display interfaces have been evolving. This is particularly important as we understand the question of how now-dominant Liquid Crystal Displays (LCD) can work with Stereo 3D.

HDMI 1.4a and DisplayPort now support transmission of Stereo 3D frames and offer ‘plug and play’ support for Stereo3D via communication of device capabilities and standard Stereo 3D transmission formats. A key point about these transmission approaches is that the matching-up of appropriate glasses (including synchronization of active shutter glasses, where appropriate) is driven by the displays supporting the standards, rather than directly by the GPU or system generating Stereo 3D content. This will further simplify Stereo 3D solutions by taking out the requirement of an understanding by the user of exactly which glasses to use with a given display type. We already see this with the availability of stereo glasses (active and passive) from the vendors of consumer TV sets, all of which support the HDMI 1.4a standard.

DisplayPort (particularly v1.2), with its significantly higher bandwidth does support 120Hz Stereo 3D, and displays supporting Stereo 3D over DisplayPort are now available. This is AMD’s preferred method of connectivity for their HD3D enabled displays.

On other desktop displays, including those supporting NVIDIA’s 3D vision, Dual-link DVI is used to allow the support of content up to 1920 x 1080 @ 120Hz although this is not standardised. This is fine for connection of PC graphics cards to drive 3D content, but of course is of no use for connecting external devices to the display. You would need to think about the availability of DisplayPort of HDMI 1.4a if you want to view 3D content from a non-PC device.

The first main stream method to reach the desktop LCD monitor market for delivering 3D content was active shutter technology using shutter glasses (SG). This is also sometimes referred to as time division switching. This 3D method is referred to as “active” since its glasses have an active role in the production of the 3D effect. It requires the use of liquid crystal shutter glasses (also called LC shutter glasses or active shutter glasses) to function. The special shutter glasses are used in conjunction with a certain type of 3D enabled display, graphics card and software package to create the illusion of a three dimensional image, an example of stereoscopy.

Each eye’s glass contains a liquid crystal layer which has the property of becoming dark when voltage is applied, being otherwise transparent. The glasses are controlled by a special transmitter connected to the display / PC that sends a timing signal that allows the glasses to alternately darken over one eye, and then the other, in synchronization with the refresh rate of the screen. Meanwhile, the display alternately displays different perspectives for each eye, using a technique called alternate-frame sequencing, which achieves the desired effect of each eye seeing only the image intended for it. So in simple terms, the glasses open and close at a very fast speed (60 times per second) and alternate between the right and left eye so that the image being viewed is only seen by one eye at a time. The synchronization of the glasses to the sequential left and right eye frames is typically accomplished using a VESA-standard 3-pin stereo connector on a GPU that connects either directly to the glasses or to an emitter that wirelessly communicates to the glasses.

SG technology has been widely used by many manufacturers and strongly promoted by NVIDIA who pioneered their “3D vision technology” for desktop LCD displays. AMD also offer a similar method using SG technology, and Samsung, Sony and Panasonic are key players in the LCD TV market and back the active shutter technology as their preferred method of delivering 3D to consumers. However, there is no industry standard defined at present which means each vendors methods (and glasses) may only work with a small set of compatible devices, and not when paired with other vendors equipment. While standardization is underway, it is important to bear this in mind when considering the purchase of a Stereo 3D solution that uses active shutter methods.

Historically, active Stereo 3D evolved in a world dominated by Cathode Ray Tube (CRT) displays. A typical refresh rate of 120Hz was chosen, corresponding to 60Hz of images to each eye. This stems from a need to ensure that with CRT displays, flicker caused by the fading of pixels (inherent in CRT technology) was not noticeable.

Since the shutter glasses are actively switching between each eye at a high frequency, you are only receiving half of the refresh rate / frame rate of the screen per eye. A normal LCD monitor would operate at 60Hz refresh rate and so that would actually provide very low refresh rates per eye if it was halved to 30Hz each. This would introduce a noticeable flicker and would not be usable on the most part. For SG technology on desktop LCD monitors there is a requirement for the screen to support a higher refresh rate of 120Hz which then matches the requirements previously outlined for older generation CRT displays. This is a true support of 120Hz input frequencies which has not been available in the past. This in turn can allow 60Hz per eye and a far higher frame rate is possible.

Not only will this allow you to use 3D content using SG methods, but it can also have uses in 2D gaming and applications. Since the screens can support a 120Hz input frequency, you can achieve double the frame rate of a traditional 60Hz screen which is important for people intending to run competitive or high end games on their display. It also helps improve perceived motion on an LCD screen, and will commonly help show smoother moving images.

Since the very operation of active shutter glasses requires the lenses to be switched continually on and off in sync with the displays refresh rate, some degree of flicker is introduced. Since the glasses are normally used in conjunction with high refresh rates (120Hz) the flicking of the lenses on and off is not visible as such. However, over time the flickering can lead to eye fatigue or sometimes dizziness and headaches. This flickering has really been one of the main issues with active shutter methods, and is also one of the key reasons why other manufacturers have switched instead to passive 3D solutions. Heavy and bulky active shutter glasses can also become uncomfortable and tiring over even short periods of time.

Some measures have been taken to help improve this area. In the desktop display market NVIDIA 3D LightBoost is a technology implemented in the monitor or notebook panel and works by controlling the panel backlight to only turn on when the LCD screen contains a ghost free-image. Since that is a short period of time, the NVIDIA GPU can turn the backlight on with higher energy which results in increasing 3D brightness. Older NVIDIA 3D Vision glasses can be used with these improved LightBoost compatible displays as well, although not to the full extent of the benefits of using the latest generation of NVIDIA Vision Glasses 2. It also works when connecting to the screen using HDMI 1.4 3D and so content from external Blu-ray players and PlayStation 3’s for instance will also benefit. Look out for monitors certified as supporting NVIDIA Lightboost.

The main manufacturer who seem to be backing passive 3D methods for monitors and TV’s is LG, and they are promoting their FPR, or ‘Film-type Patterned Retarder” technology to give it its full name. FPR is a technology which is being heavily developed by LG.Display, who are very prevalent in the desktop monitor panel market and are responsible for producing the majority of IPS panels which are increasingly popular and widely used.

LG.Display (LGD) first declared its ambition to command the global 3D market at the Launching Ceremony for FPR 3D, held on December 9 at the Paju plant in Korea. With 45 participants related to the FPR 3D project including president & CEO, Young Soo Kwon, the ceremony was held to reconfirm the ambitious goal of LGD to become No.1 in 3D and inspire determination to accomplish the goal no matter what. The first FPR display was then unveiled by LG.Display on December 15th 2010 in Beijing, which included demonstrations comparing their new FPR technology against the more established shutter glasses (SG) technology.

The CEO of LG.Display, Young Soo Kwon said in his speech at the event that “On behalf of LGD, I am greatly delighted to declare the beginning of ‘the era of FPR 3D’ in China, which is fast becoming the centre of the global TV market,” and added, “Even though LGD has been developing both SG and FPR 3D technology, LG Display will focus on FPR 3D products as we believe that FPR is superior in all aspects and represents genuine 3D technology better suited to consumers.”

FPR is also sometimes called “space division switching” or “passive polarization” due to the method in which it delivers 3D content to the end user. A FPR display sends left/right images at the same time, and then separates the left/right signals through a patterned retarder film that is attached to the panel. The polarizing glasses that the viewer wears deliver these images to the corresponding eye. The passive polarization will deliver half of the horizontal lines (vertical resolution) per eye, meaning 1920 × 540 pixels per eye. This is often viewed as an issue with FPR methods which we will discuss later on in this article.

Unlike SG methods which require 120Hz input signals to work (in order to deliver 60Hz per eye), an FPR display will only operate at 60Hz and does not give 120Hz support. Consumers need to be wary that “3D support” does not necessarily give you 120Hz input support, which some people are looking for in order to give them higher refresh rates and frame rates from their screens for regular 2D content.

Here we will discuss the various features and selling points of FPR as a 3D technology. Keep in mind much of this content is based on LG.Display’s perception of their technology.

Since existing SG type displays use glasses that alternately open and close the right/left lens, flickering can be a serious problem. This can lead to headaches, dizziness or eye fatigue if it is viewed for long periods of time. However, the FPR type realizes a ‘comfortable-to-eye 3D image’ without flicker. The glasses are not actively shutting the lenses in any way and so this flicker is eliminated.

At the LG.Display press event in Dec 2010 a presentation by the Research Institute of TV and Electro-Acoustics (which is a part of the Ministry of Industry and Information Technology of China) and the Beijing Ophthalmology Research Institute was made. This presented their test results on FPR products and concluded that, “After analyzing flickering, an occurrence in watching 3D TV, FPR panels are less tiring to the eyes compared to shutter glasses panels.”

The FPR displays a bright three-dimensional image by allowing sufficient amounts of light to pass through the open glasses. On the other hand, SG type TVs use liquid crystal lenses for their glasses that allow poor light penetration, it displays a much darker image than FPR generally. Recent improvements have been made to active shutter glasses as discussed earlier in this article. The higher brightness of FPR is still used as a reported benefit of this 3D method.

At the unveiling of the first FPR display in Dec 2010, audiences familiar with heavy and bulky SG system glasses were reportedly particularly impressed with the light and comfortable polarizer 3D glasses after trying them.

The core technology for a 3D display is ‘How accurately it can deliver left/right images to each eye to realize a vivid and clear image’. Due to complicated signal processing and shutter movement, SG type TVs cause screen overlapping (crosstalk) where the image intended for the opposite eye leaks in. Since FPR type TVs separate the left/right images more clearly, they are designed to realize a crisper and clearer three dimensional image.

One of the regularly cited ‘limitations’ of passive 3D methods like this is its supposed lack of support for true HD content. FPR technology, adopting space-division, displays both the left and right eye image at the same time by using lines of resolution. Of the 1,080 lines of resolution that make up Full HD (1920 x 1080), the left eye sees the odd lines while the right eye sees the even ones. This leads to the conclusion that only 1920 x 540 is being seen by each eye which is strictly correct. However this is sometimes wrongly interpreted to mean that an FPR display cannot display full 1080p resolution content. In the end, the viewer can see the Full HD image when the left image is combined with the right image, albeit with each eye seeing half lines of resolution.

LG.Display are keen to re-emphasise these points through their newsletters and marketing. To support this further recently the vDE Association for Electrical, Electronic and Information Technologies e.v., one of Europe’s largest technical-scientific associations, verified through a strictly impartial picture quality analysis that FPR 3D TV displays full HD (1080p) resolution in 3D mode taking both eyes into account. Similarly in February, China Electronics Standard Institute announced that FPR 3D TVs meet full HD standards for both horizontal and vertical resolutions.

For FPR to work, a special film is applied to the front of the display which produces the 3D effect. The passive glasses filter the image so that the resolution is being split in affect vertically in two portions. The black bars which break the horizontal and vertical stripes on the passive filter can sometimes create visible stepping effects in an image and cause it to look jagged or appear interlaced. Indeed, the reduced horizontal resolution of the Passive 3D system has a screen texture that looks remarkably similar to older cathode ray tube TV sets. SG is often considered to offer a sharper image as a result, most notable on curving and diagonal edges.

FPR is an advanced “new generation 3D technology” according to LG.Display since the 3D effect is created through the screen itself as opposed to through the glasses. Glasses are still used of course, but the screen is creating the 3D effect. This will later lead on to non-glasses 3D screens with panel technology producing the 3D effect.

At the December 2010 launch event Dr. James Sheedy, Director of the Optometry Research Center at Pacific University in the U.S., delivered a lecture entitled “Vision and 3D Display.” Dr. Sheedy highly praised LGD’s FPR 3D panel saying that “Problems with the SG type panel included the weight of the glasses, power consumption and reduced brightness. However, LG Display’s FPR 3D panel has no flickering, produces minimal cross talk and delivers a bright screen. Also, the glasses can be made with curved lenses, like regular glasses, so it is superior in terms of protecting eyesight.”

Much of this section is taken from LG.Display’s website and documentation which serves as a Q&A to address common misconceptions and misunderstandings about FPR 3D technology. Of course take it with a pinch of salt but it is still helpful in understanding the positioning of their 3D technology:

A. The basic 3D technology is to make use of the binocular disparity caused by the distance between the left and right eye (6.5 centimetres on average). That is to say, a stereoscopic image can be created when a separate image is seen by the left and right eye sequentially. For this 3D effect, glasses with SG technology, adopting time-division, ceaselessly alternates the left and right image by blanking out one eye after the other rapidly. In other words, one eye sees the image while the other eye sees nothing, and thus, one eye sees the Full HD image while the other eye sees zero-resolution. on the other hand, FPR technology, adopting space-division, displays both the left and right eye image at the same time by using lines of resolution. Of the 1,080 lines of resolution that make up Full HD (1,920 x 1,080), the left eye sees the odd lines while the right eye sees the even ones. This leads to the conclusion that only 1920 x 540 is being seen by each eye which is strictly correct. However this is sometimes wrongly interpreted to mean that an FPR display cannot display full 1080p resolution content. However, in the end, the viewer can see the Full HD image when the left image is combined with the right image, albeit with each eye seeing half lines of resolution. Therefore, FPR and SG are only different in format, and thus it is logically wrong to say that FPR cannot deliver Full HD picture quality.

A. 42” or 47” FPR 3D panels’ viewing angles (up/down) may vary according to speculation, but currently, they are approximately 25~30 degrees. Therefore, in the general 3D environment or when watching TV at a distance of more than 1.5 meters from the display, viewers can enjoy the 3D effect. As for TVs ranging from 40” to 49”, ergonomically speaking, viewers can see a clear image without any crosstalk at a distance of more than 1.5 ~ 3 meters. Many ophthalmologists also warn that it is harmful to the eyes when watching TV at a distance of less than 1 meter. Moreover, when watching TV at too close a distance, viewers have no choice but to see a blurry image because the partial image on the screen is out of focus.

Early in 2011 saw the 3D battle heat up significantly with Samsung and LG exchanging heated words and aggressive marketing activity over which technology was superior, SG or FPR. LG.Display addresses this in their LG.Display’s monthly magazine (April 2011 issue) and covers some of their arguments about FPR’s superiority quite well:

On March 10, LG Twin Towers heated up with the fervour of some 120 reporters who came to cover LGD’s CEO press conference on “proving the superiority of FPR 3D technology.” Two days before the conference, a competing company had made groundless claims that FPR was inferior to that of their own—sparking up the controversy over the superiority of current 3D TV technologies—and the press were eager to find out how LGD would respond. President and CEO Young Soo Kwon began the conference by saying, “I would like to apologize to the consumers for having let the recent war of words between LG and Samsung go slightly out of hand,” and added, “We have therefore prepared this conference with the purpose of putting an end to the confusion as early as possible.” He went on to show respects to the competing company in a most sophisticated manner by saying that the competing company’s president was an admirable entrepreneur and he thought very highly of the company—who had been a friendly rival for a long time. However, he was resolute in his words when saying that he requested they refrain in the future from creating anymore slander advertising or holding unproductive and unnecessary debates.President and CEO Young Soo Kwon personally led the conference from the beginning by asserting that if SG (Shutter Glasses) technology is the first generation 3D technology, FPR is the technology of the next generation. Next in line came clear and organized refutes to the claims of the competing company, parading the advantages of FPR 3D. The first issue, and the biggest, was about providing full-HD images. President Kwon showed unwavering confidence on the matter, saying that FPR 3D TV’s capability in providing full-HD 3D images has already been validated by world-renowned certification bodies such as Intertek and China Electronics Standards Institute, and they will also receive such validation from all other authorities in the future. He went on to introduce the results of a “3D TV consumer evaluation,” conducted by an online media with IT power bloggers and some thirty twitterians participating, and revealed that FPR out-rated the competing technology in numerous aspects including 3D effects, flickering, resolution, and brightness. He also proposed to the competing company, which had abruptly refused to participate in the comparative demonstrations of the products promoted by the Korea Communication Commission and Daum Café, that they both participate and see who comes out on top. In addition, Kwon commented on the so-called “monkey advertisement,” published by the competing company, and made his position clear by saying that he hopes there will be no more slander advertising.

The issue about crosstalk and flicker were also raised. President Kwon said that these two issues were the main causes of headaches, dizziness, and eye fatigue, giving examples of the recommended 3D TV viewing-time, announced by the Japanese 3D consortium and Korea Communications Commission. He then revealed that many world-renowned authorities had announced SG products to be potentially harmful to the body because of flickering, adding that FPR 3D has already been validated as flicker-free by TÜV whereas SG 3D had failed to do so. In addition, he disclosed the information regarding crosstalk, where FPR (0.6%) was far more superior to that of SG (2.6~6.8%). At the conference, LGD had prepared a booth for actual demonstrations in order to help the press understand the difference better. Two different environments of natural light and night setting were created, and the company compared LG Electronics’ FPR 3D TV with the competing company’s latest SG 3D TV. The LG product displayed smooth 3D images even under fluorescent lighting, whereas the competing company’s product showed flickering from the interference created by the lighting. Most of the press acknowledged LGD’s statement to be true.

Last but not least was the viewing-angle issue. President Kwon introduced the results of a study, conducted in Japan, on reasonable TV viewing-angles. He emphasized the fact that FPR 3D TVs, which uses the IPS technology, display clear 3D images anywhere within the reasonable TV viewing-angle, whereas SG products start displaying dark images when the viewer tilts their heads to the side and nothing can be seen when the viewer lies down. In addition, he stated that the glasses used in SG technology make it unsuitable for many people to watch at the same time as it shows various problems, including weight, electromagnetic waves, eye fatigue, and inconvenience of use, while FPR glasses, which are similar to that of ordinary glasses, possess various advantages such as cheaper price, compatibility, and convenience. Lastly, President Kwon said that 3D technology has evolved from the 1st generation of SG, where glasses played a big role, to the 2nd generation of FPR, which has minimized the role of glasses, and projected that ultimately, it will become glasses-free. However, he added that commercialization of glasses-free 3D will take some time, due to the problem related to resolution as well as the involved cost, and therefore, FPR is the real 3D technology that reflects the needs of consumers, the technology that will revolutionize the market.At the Q&A session, held after the speech, President Kwon revealed that five Chinese companies are currently manufacturing or have plans to manufacture TVs using FPR 3D panels, and world-renowned companies in the US, Europe, and Japan have also begun purchasing FPR panels. In addition, he said that he also expects more monitors to be produced using FPR 3D panels, and he is confident that LG Group’s FPR 3D will become the new standard of the 3D market.

Within LG.Display’s newsletters, LG have also been quick to post results obtained from various evaluations. These are detailed below, but again keep in mind the source. The studies do seem to bring out some positives of FPR and passive type techniques however:

In the desktop 3D monitor market, NVIDIA are probably the biggest player. NVIDIA launched its 3D Vision technology back in January of 2009, giving consumer-level 3D gaming the biggest endorsement it had ever received. The past three years they have grown this technology into a central feature, exclusive to their GeForce graphics product line, and also further evolving into a triple-display capability they’ve dubbed “3D Vision Surround”. Their own NVIDIA 3D Vision technology is incorporated by many manufacturers and by many displays.

An NVIDIA 3D vision experience requires several elements as outlined above. You must have their proprietary active shutter glasses kit which comes with an IR sensor / emitter which connects to your PC. NVIDIA have created an end to end system for delivering 3D where the glasses are a big part and must be combined with 3D Vision certified displays and graphics cards.

The glasses themselves are designed to work with 3D Vision monitors and notebooks, but NVIDIA IR emitters cannot be used with most SG supporting 3D LCD TV’s or projectors. You must also have a 3D Vision ready display which supports 120Hz refresh rates. You also need a compatible graphics card and PC set-up, and of course relevant 3D content and (in-house supplied) drivers to display the stereo 3D images. The graphics cards from NVIDIA’s range commonly have a dual-link DVI output to be able to handle the full 1920 x 1080 resolution at 120Hz. As a result your display must feature DL-DVI to be able to use NVIDIA’s solution at its full potential.

A list of compatible displays, notebook PC’s, TV’s, projectors and graphics cards can be found on NVIDIA’s website (although not exhaustive). When you’re looking to build a 3D-capable gaming system, NVIDIA’s approach is considered simpler than the AMD HD3D option because you’re only looking for one proprietary certification, 3D Vision. You can also use multiple cards in SLI to boost performance, and that’s a nice option to have since stereoscopic 3D effectively halves frame rates, often demanding more potent graphics hardware for your favourite games.

The Samsung 2233RZ, BenQ XL2410T and more recently the BenQ XL2420T are three displays we have tested which are compatible with NVIDIA’s 3D Vision technology. Some screens will come bundled with the NVIDIA 3D vision kit (glasses and sensor) and some would require you to source them separately. The Asus VG278H is a 27” model with a built-in 3D Vision 2 emitter and a bundled pair of new glasses. NVIDIA also lists the Acer HN274HB and BenQ XL2420T / XL2420TX as 3D Vision 2-certified monitors which are new to the market or being released very soon.

AMD’s HD3D system is another alternative method for delivering 3D content in the desktop monitor market. AMD arrived in the 3D market a little later than NVIDIA in October 2010 and have adopted a slightly different approach. Unlike NVIDIA and instead of a proprietary system, AMD provides driver hooks to software developers and leaves 3D displays and glasses to third-party providers. Their graphics cards can be used with passive polarized 3D display and 120Hz active shutter display types alike. There is no glasses or monitor standard whatsoever.

Obviously the main component here is the AMD graphics card which must be capable of supporting 3D content. From there you will need a compatible display, whether that’s a desktop monitor, an LCD TV or a projector. For a desktop monitor you should have a DisplayPort connection ideally, as AMD have widely opted to use this as their high bandwidth interface instead of Dual-link DVI. This will allow you to use a full 1080HD (1920 x 1080) resolution at 120Hz as the bandwidth of DisplayPort can support that. Some desktop monitors have aligned themselves with either AMD or NVIDIA through their choice of either DisplayPort or DL-DVI really, so keep that in mind when selecting a screen. For an LCD TV or projector where DisplayPort is not offered you will need to have HDMI 1.4a available. However, due to bandwidth limitations you are only able to use this at 720 HD resolutions (1280 x 720) at 120Hz (i.e. 60 frames per eye). At a full 1080 HD resolution you are limited to 24 frames per eye. As DisplayPort becomes more popular in desktop monitors and other screens this limitation will be overcome and high bandwidths will be supported more easily.

AMD are also working with major ISVs like Roxio to enable Blu-Ray 3D playback through their technology and are working with various glasses manufacturers as well. They feel that there should be industry standards for stereo 3D support and want interoperability between different products from different manufacturers. They are also incorporating 3D support via DisplayPort interfaces as well as HDMI 1.4a.

A list of supported hardware including graphics cards and monitors is provided by AMD on their website. Recent monitor releases including the Samsung 750 and 950 series feature AMD compatible 120Hz SG technology and a DisplayPort interface suitable for use with HD3D at full resolution.

Another aspect of 3D content is of course movies. We have looked already at the various methods of displaying 3D stereoscopic content and the technology involved. Obviously there are a wide range of ways you can gave in 3D, whether you convert traditional 2D content or play games supporting native 3D modes. The other popular use of 3D is in movies, where it is already becoming far more common in cinemas and now also in the home. To support 3D content, the Blu-ray file format is now commonly used, although you will also find various pieces of 3D content in other formats online, or in downloadable format. These are often very large in file size which is why the storage capacity of Blu-ray is ideal for delivering 3D movies and content.

Looking briefly now specifically at desktop displays, I wanted to touch on the current associations between support of 3D content and panel technologies. When 3D support first started to appear in the mainstream desktop monitor market (ignoring older pro / specialist screens), it was exclusively linked to TN Film panels. Initially the main method for delivering 3D was using SG methods and active glasses and even now, all of the current desktop monitors with SG technology are based on TN Film panels. There has been a significant development from panel manufacturers in this regard, working to develop their TN Film modules to offer support of SG 3D and also of the all-important 120Hz refresh rate. Most of the main panel manufacturers now offer 120Hz compatible modules based on TN Film technology. As a result you will see many models in the market using TN Film and offering 3D /120Hz support. This has also been done to help keep costs down, and also tap in to the inherent responsiveness of TN Film technology, since the primary use of many of these screens is gaming. TN Film has been exclusively linked with SG active 3D methods at the moment, and no passive alternatives.

LG.Display as we have discussed are not backing SG methods for 3D delivery, and are instead investing heavily in FPR and passive 3D methods. As such, we have not seen any IPS panels (LG.Display manufacturer nearly all the IPS panels in the market) which will support 120Hz refresh rates needed for SG 3D. Instead, we have started to see some IPS panels emerge with FPR support, and so IPS does offer 3D support, just not using 120Hz refresh rates and SG. Uptake of these panels by monitor manufacturers has only been quite recent but we are starting to see more IPS + 3D models emerge. It is unlikely that LG.Display would also develop a 120Hz compatible IPS panel (for SG methods) but I would not rule it out completely.

Samsung are the other panel manufacturer who currently supply common alternatives to the technologies already mentioned. They manufacturer and produce their own PVA and new PLS technologies. The latter is very recent and has only been used in a couple of monitors so far such as the Samsung S27A850D. This was designed as an alternative to LG.Display’s IPS and so if successful we would expect it to perhaps become their primary alternative technology (other than TN Film). At the moment we have not heard of any plans to combine PVA or PLS with 3D methods, although I suspect a 3D PLS panel may emerge at some point in the future. It remains to be seen whether that would use SG or passive methods, but given Samsung’s direction in the LCD TV market I would expect it to be an active method.

3) Connect the TF card to the Raspberry Pi, start the Raspberry Pi. The LCD will display after booting up, and then log in to the Raspberry Pi terminal,(You may need to connect a keyboard and HDMI LCD to Pi for driver installing, or log in remotely with SSH)

Do you know lcd display advantages ? The appearance of the LCD liquid crystal display can be traced back a long time ago. At the end of the 19th century, Austrian botanists discovered liquid crystals. Subsequently, British scientists used the electro-optical effect of liquid crystals to create the first LCD liquid crystal display. Nowadays, LCD screens are used in video surveillance (security) for more than 50%, and they are widely used in public services, transportation, energy resources, finance, and other industries. The following Proculus will introduce you to the five advantages of the LCD display module.

LCD Display includes lcd android and uart lcd display. The display principle of the lcd monitor module is to realize the restoration of the picture by twisting the deflection angle of the liquid crystal molecules in the liquid crystal pixel. The LCD liquid crystal display does not have internal ultra-high voltage components like CRT, so there will be no X-ray excess due to high pressure. Moreover, the structure and circuit of the machine screen are simple. Modularization and high integration of the chip are sufficient to minimize the electromagnetic radiation generated when the circuit is working. This design directly reduces the power consumption and heat generation of the circuit. Although the liquid crystal display module may produce slight electromagnetic radiation when it is working, this problem can be solved by shielding the circuit. As the CRT display screen considers heat dissipation, it is not allowed to drill holes in the shielding cover to cause radiation leakage.

It is the appearance of the liquid crystal display module that made the invention of the portable computer possible. Similarly, although desktop LCD screens are larger in size and weight than laptop computers, they are insignificant compared to bulky and heavy CRT screens. Compared with a 15-inch display screen, the depth of a CRT display screen is generally close to 50 cm. With the changes in consumer opinions and living environment, people have higher and higher requirements for the volume and weight of household electric screen products. The LCD display module has become the most likely display device to break the monopoly of CRT display due to its inherent advantages of slimness and lightness.

The LCD display module adopts the direct digital addressing display mode. It can directly correspond to the video signal on the screen one by one according to the address signal in the signal level after AD conversion of the video signal output by the graphics card. Displayed on the liquid crystal pix