Do you Want to Know the Differences? LCD display and LED display

Differences between the LCD display and LED display


We do believe that technology today is achieving incredible milestones. Every day we have new food for thought. The miracles of science and technology keep on surprising us regularly. Display technology is one such field where innovation is occurring rapidly. From the earliest display to present day LED signs, the display screens have gone through many transition phases. This article is really helpful for readers interested in knowing key differences between the LCD display and LED displays.


What is the LCD? A quick recap


LCD is an acronym of Liquid Crystal Display. An LCD panel mainly comprises liquid crystal molecules. Electricity is induced to excite them. The electrons once excited adopt different paths that can either restrict or allow the light to pass. There is always a light source behind the display panel that lit up the liquid crystals. The most commonly used backlight source for LCDs is Cold Cathode Fluorescent Lamps.

The LCD displays feature blue, red, and green sub pixels in every screen pixel. Each display screen is embedded with transistors. They are largely involved in controlling the direction of emitted light from each pixel. The light then passes through a blue, green, or red filter. Normally LCD displays show the content, be it images or text in the form of segments and dot matrix.


LCD- a fundamental technology


LCDs displays have become part and parcel of modern displays they have extensive application in televisions, computer monitors, smartphones, and tablets. Do you know that conventional televisions worked on cathode ray tubes? However, they were successfully replaced with LCD displays once the technology becomes affordable.


What is an LED?


led display



An LED is an acronym for a light emitting diode. These LEDs are semiconductor in nature. When an electric current passes through it, electrons get excited and thus emit visible light. They are extensively trending due to its efficiency, cost-effectiveness, and lower maintenance cost.


Differences between LCD and LED displays


Since the LED displays are the latest technology definitely it will have some improvements as compared to LCD displays. We will be discussing the differences between the two as follows


Material: LCD displays are made up of liquid crystals along with glass electrodes while LED displays are made up of Gallium arsenide phosphide.

Power required per digit: LED displays require more power around 10-100 mW than LCD displays for local dimming. Contrary to this LCD displays require less power i.e. around 100µW. actually, it is a trade-off between economical electricity bill and better picture quality. Less power requirement for LCD displays is because of plasma that requires very less power to boot up.

Operating voltage: LCD displays work on low to medium voltage. LED billboards can work well even on low operating voltages.

Speed: The speed of LCD displays is less. LED displays today feature nanosecond technology. They process at the spur of a second. Since the viewer can spare maximum 6seconds to LED billboards, promptness is very necessary.

Switching time: LCD displays have more switching time than LED displays. Talking in simple terms switching time is the activated /deactivated time of the displays.

Lifespan: LCD displays have relatively less life span. Investing in LED displays can bring you countless benefits. Their life span is relatively longer. The shelf life is normally 100,000 years or 11 years. However, they can even work beyond this time span.

Contrast ratio: The contrast ratio of the LCD display is 20:1 while for LED displays it is 10:1. LED displays offer better contrast and black level as compared to LCD displays. This is because liquid crystal is unable to prevent all backlight originating from cold cathode backlight. Therefore, when the black screen appears on the monitor, it is not 100% black. Conversely, as there is no backlight system in LED displays it shows true black color.

Resolution: LEDs have a better resolution power as compared to LCDs. Resolution means the total number of pixels on the display screen.

Ease of mounting: LED displays are the slimmest version of displays ever. They are intentionally kept lightweight for a number of reasons. Therefore, they offer ease of mounting. LCD displays are difficult to mount.

Mercury usage: LED displays do not employ mercury for its working. However, the earlier technology of LCD displays uses mercury in cathode tubes involved in backlighting. LED signs are more eco-friendly.

Effect of direct current: LED displays remain unaffected when exposed to direct current. But the case is opposite for LCD displays. Direct current exposure verily reduces their life span.

Price: Since LCD is an older technology now relative to LEDs, the LCD displays cost you less. LED displays are truly magical due to high resolution, high definition, and crisp quality of images. However, the technology is still unaffordable to masses. The slim trim body, perfect screen quality and hi-tech features are really hard to resist. LED billboards and LED digital signs are surely the attention grabber.

MOS compatibility: LCD displays offer MOS compatibility. LED displays offer MOS compatibility only for smaller versions.

Viewing angles: if the viewing angle exceeds 30degrees from the middle the contrast ratio of the appearing image is decreased in the LCD display. This put strain on the eyes. LED displays counter this problem well by offering wider angles. The image remains clear even if viewed from the sides.

Color accuracy: the color accuracy of LCD displays is more or less the same as direct or edge LED displays. However, RGB LEDs have an inherent color accuracy advantage above all others.

Colors of displays: LCD displays that show a colorful content should employ three sub-pixels compulsorily. These are blue, green, and red. We can extract 256 shades from each pixel just by careful control and slightly varying the applied voltage. If we combine all possible shades from each pixel, we have a diverse shade palette of 16.8million colors. But remember, LCD displays need a huge number of transistors. If any transistor goes dead it will lead to a monochrome bad pixel.

LED displays are available in monochrome, dual color or full-color (tricolors) features. Monochrome was the earliest form of LED display and only display the message. Technological improvements led to the discovery of dual color and full color LED displays. Tri-color LED displays are the recent and the most trending displays. They can display any form of content including graphics, text, images, alphanumeric content, and event animation videos.

Display size: There is a limitation on LCD display size due to quality control problems. To stretch the display size manufacturers need to add more transistors and pixels in operation. While extrapolating transistors and pixels there is a probability of including malfunctioning or bad transistor. Normally 40% of LCD panels undergo rejection coming off from the assembly line. The rejection escalates the LCD display price. Why? Because selling LCDs will also include the cost incurred on rejected panels. The only way to lower LCD price is incorporation of technology and lower rejection score.


The display size of LED billboards and LED signs can go at any length. Digital display manufacturers like DAKCO offer great flexibility in customizing your own LED displays. Now you decide what you actually want. However, the best Led billboard or LED sign need a few considerations. Optimum viewing angle, distance, pitch, pixel density and of course budget all require due consideration. If you are still confused you can discuss with the congenial staff of DAKCO for further guidance. LED video displays or LED video walls offer amazing size displays. It looks superb when crystal clear images and video run flawlessly on giant size screens. Actually, these walls are composed of enormous LED screens integrated together. The bezels are tight to give a seamless appearance.


Evolving technologies of LCD displays


Technological advancements are also taking place in the field of LCD displays. There are many variations of LCD displays as well. Hence, it’s to time to know something new about liquid crystal technology.

Super twisted Nematic displays (STN): scientists discovered the basic idea about Super twisted Nematic displays in the early 1980s. Main idea was that if the twist angle of liquid crystal in increased about 180 degrees to 270 degrees, the row which appears contain a larger number of pixels and exhibit superior characteristics.

Dual scan twisted Nematic displays (DSTN): it is an improved version of STN passive matrix LCD. The screen splits in two halves. Each half undergo scanning process simultaneously. As a result, the total number of lines that are refreshing per second simply double. Therefore, sharper images are formed.

Ferroelectric liquid crystal (FLC): This display technology accounts for the ferroelectric characteristics of chiral smectic, a liquid crystal


Evolving types of LEDs


LED signs have undergone extensive innovation. Today you can easily find varying types of LED displays. To make your purchase final you will be choosing either of these three LED types. These LED displays are segregated according to the placement of LEDs behind or around the screen.


Edge-lit LED


As the name indicates, in this form of LED displays the LEDs are grouped around display rim at the backside of LED display panel pointing in the direction of the screen. Because of this, the display width remains slim, also, fewer LED will reduce the overall cost of the display. The light reflects evenly across the display screen and create a well-defined image. Some users however report that Edge-lit LED displays are brighter on points closer to LEDs. So, some area might appear relatively darker. But remember, if you are dealing with the right digital display manufacturer like DAKCO all your issue will be fixed.


Full-array LED


This LED display encompass LED lights grid behind the display screen. When an electric current passes, these LEDs emit light and forms an even and bright image. Full-array LED displays exhibit all the benefits of LEDs. To produce the best quality image, full-array LEDs can works on the principle of local dimming. It simply means that LEDs are easy to switch on/off as and when needed. It will greatly help in adjusting the brightness. Full-array LEDs are also termed as FALD LED displays.


Read more: Recent Outdoor LED Display Market Trend



Normally we consider that LEDs radiate white light. However, the reality is bit different. They actually produce light near to yellow shade than pure white. Therefore, you might have experienced a color shift while viewing displays. To settle the situation reliable digital manufacturers like DAKCO use RGB LEDs instead of white LEDs. Digital signs with tri-color LEDs emit white light and normally vivid colors throughout the spectrum. Incorporation of RGB LEDs is not easy because it requires more number of LEDs along with advance programming and electronics.


Which display is safe for eyes?


LED displays are actually an extension of LCD displays. However, LED signs or billboards employ LEDs for the purpose of back lighting. In conventional LCD displays, fluorescent tubes were the backlighting source. And they radiate Ultra violet rays too. Besides this modern LED displays are usually back-lit or edge-lit by LEDs, therefore they are not hazardous for eyes at all. They are the safest option for sure.


Cylindrical LED is the new talk of the town


led cylinder



Cylindrical LED is another worthy invention of scientists. They have come up with something that is both functional and aesthetically appealing. A 3D cylindrical LED will simply blow your mind. It involves laser cut interlocking segments that integrate together to form the frame of the display. In the absence of a laser cutter, the same design can be achieved via 3D printed parts. Strips of LEDs are placed inside the cylinder lengthwise. This arrangement lines up an equal distance from the central point. The exterior wall is modified using Micro WOOD.

You may inquire about what micro wood is. It is actually a thin wood of veneer. It gives a perfect gentle glow. The overall look is so fresh and organic because of veneer wood grain. Of course, a sophisticated software will be driving the overall functions. While connecting with the system and using certain software it is possible to see how the display will appear if flattened