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Information and background knowledge.

We would like to offer you the opportunity to familiarize yourself with our products.
We are happy to share our knowledge with you and clarify unknown terms.

 

       
A B C D E F
AC Power Frequency Brightness Calibration Digital Signage   Frame Rate
  Brillance COB-LED DIP-LED    
    Color Temperature      
G H I J K L
Grey Scale   IP-Rating     LED
          Legal Advice
M N O P Q R
Mobile Solutions Narrowcasting  
(Explanation)
  Refresh Rate
      PFC-Power-Supply   Resolution
      Pixel    
      Pixel Pitch    
S T U V W X / Y / Z
SMD-LED Tipps to Permits   Videowall    
      Viewing Angle    
      Viewing Distance    
      Virtual Pixel    

  

 

   

AC Power Frequency (Frame Rate)

The frame rate is used to simulate a video wall with fine color and grayscale transitions through very short image sequences. A processor controls the switching on and off of the individual diodes (in nanoseconds). The human brain perceives this as a flowing course.

Unit: hertz / megahertz (Hz / MHz)

   

Brightness / Brillance

This simply indicates the brightness of a LED system.

Unit: NIT
EU Unit: cd/m² (Candela per square meter)


In the outdoor area, a good 5,000 NIT are common, as weather conditions can make the view of a video wall difficult. At present, up to 9,000 NIT are possible.

   

Calibration

When composing video walls from individual modules, they must be matched in terms of both color and brightness. This applies to screen walls and also to LED walls made of individual panels. Both, screens and LEDs, lose some of their brightness over time. In addition, different batches are not identical. This usually leads to problems when exchanging or buying individual displays or panels.

If you replace a single display within a video wall, this usually has to be recalibrated. There are different ways to do this. While on screen walls, each device is often measured individually with a spectrophotometer and corresponding calibration software, a camera is often used in the calibration of LED video walls. A manual adjustment is usually possible, but those results are not as good and you will see the differences of the individual devices.

If you want a professional calibration and, for example, studio-compatible, you should create your own ICC color profiles for each device. However, this requires appropriate equipment and experience.

We offer a recalibration for almost all devices and modules.

   

COB-LED

Chip-on-board (COB) technology attaches the LED chips directly to an aluminum circuit board. Due to the good heat transfer, many chips can be mounted in a confined space and generate enormous luminous flux. Likewise, they are very flat and therefore very space-saving.

   

Color Temperature

The color temperature (or light mood) is a measure for determining the respective color impression of a light source and is given in Kelvin. White light can be reddish-yellow (warm white) or bluish-white (daylight white). With a high proportion of red, white light looks warmer and a little darker. With a high proportion of blue, however, cooler and a lot brighter.

The following guideline values orientation:

warm white (<3.300 K - high red 
proportion. . . . . . . . . homely / cozy
neutral white (3.300 up to 5.300 K) 
. . . . . . . . . . . . . . . stimulating
daylight white (>5.300 K - high blue proportion) 
. . . . . . increasing concentration and performance

Living Room / Bedroom 
. . . . . . . . . . . . . . . . . . . . . . appx. 2.700 K
Kitchn / Bath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . appx. 3.000 K
Office 
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . appx. 4.000 K
Industry 
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . appx. 6.500 K
Specialists (for example photographers) 
. . . . . . . . . . . . appx. 8.000 K

   

Digital Signage

The term Digital Signage describes the use of digital media content in advertising and information systems. For example, electronic posters, traffic signs, in-store advertising, digital door signage or large screen projections.

   

DIP

The DIP-LEDs are currently the best known. Most commonly used are DIPs at 0.06 watts. DIP LEDs have a faster lumen decrease than the newer generations.

after 2.000 hours = ca. 15% lumen decrease
after 3.500 hours = ca. 20% lumen decrease

theoretical lifespan:  > 50.000 hours
actual lifespan: 10.000 – 15.000 hours

   

Grey Scale

Gray Scale describes the visually spaced gray tones between black and white. These differ only by the gradation of the color brightness.

   

IP-Rating

IP20

2 - protection against solid objects larger than 12,55 mm diameter
0 - no protection against water


IP21

2 - protection against solid objects larger than 12,55 mm diameter
1 - protection against falling dripping water


IP31

3 - protection against solid objects larger than 2,5 mm diameter
1 - protection against falling dripping water


IP40

4 - protection against solid objects larger than 1,0 mm diameter
0 - no protection against water


IP43

4 - protection against solid objects larger than 1,0 mm diameter
3 - protection against spraying water


IP54

5 - dust protection
4 - 
protection against splashing water


IP65

6 - dustproof
5 - protection against jet water

   

LEDs

LEDs are light emitting diodes. They have a lower power consumption than conventional bulbs and a longer lifespan. If an LED does not have the highest quality, the overall quality of a video wall suffers.

   

Mobile Solutions

In addition to permanently installed video walls - especially in the rental area - mobile devices can easily change the location if necessary.

   

Narrowcasting

On the Internet, narrowcasting is a service that is tailored precisely to a specific audience.

   

PFC Power Supply

Power Factor Correction / Power Factor Compensation

An active or passive power factor correction filter is an electrical / electronic circuit which increases the power factor to remain within a regulated range. Applications: Electronic consumers with switched-mode power supplies connected to the public power grids.

   

Pixel

Pixels are the smallest unit for defining a pixel. Each unit (pixel) consists of 3 LEDs in the primary colors red, yellow and blue (RGB). The higher the number of pixels, the higher the resulting image resolution of a video wall.

 

   

Pixel Pitch / Pixel Distance (P)

The pixel pitch results in the resolution of a video wall. The distance arises from the gap between the center of one diode to the center of the next adjacent diode. This distance currently has a bandwidth of approximately 1.50 mm to 25.00 mm. The smaller the distance between the individual LEDs, the higher the resolution and the finer the image.

 

Pixel_Pitch_Darstellung_00

 

 

 _________ P4 _________________ P7 ________________ P10 _______________ P12 ______________ P18 ___________

Wiki-Pitch-Darstellung

   

Refresh Rate

The refresh rate is the number of displayed individual frames per second.

   

Resolution

We divide LED video walls into four categories.
Here, the format and the maximum resolution of the LED wall determines in which category we classify it.

  1. Info

    LED walls in category "INFO" usually have a resolution that is below the quality of a normal TV picture. This means that detailed images or videos, as well as small texts will be displayed poorly or not at all. These LED walls are suitable for displaying large letters and marquees. An example of this would be the perimeter advertising board in a stadium.

     
  2. Video

    LED walls in category "VIDEO" have a picture quality that corresponds approximately to a TV picture. You can display videos and also texts in good quality. Simplified, you can say that from a sufficient distance a video wall of the type "VIDEO" looks exactly as if you have a normal (not HD) television picture.

     
  3. Poster

    Of course, LED walls of the "POSTER" category can also play videos in high quality. Here the picture quality is comparable with a HD TV picture. But it can also represent smaller writings very well. This is necessary, for example, if you want to present an advertisement or information for which you would otherwise have printed a poster.

     
  4. Presentation

    Videowalls of the category "PRESENTATION" have the highest resolution and can be within the range of Full HD or above. Everything can be displayed perfectly on these LED walls. The videos in most cases even surpass the quality of good cinemas. However, they are often used in conference rooms or studios. Here they often show PowerPoint presentations with very small numbers and letters. Quite often, such presentations contain excerpts from Excel spreadsheets. These have extremely small fonts and fine lines. To display such information clearly requires very high resolutions.
     

SMD

SMD LEDs consist of 3 diodes each, which are soldered together by surface mounting on a circuit board in a housing. Conventional diodes, however, are inserted individually with wires on the board.

The SMDs allow a smaller pixel pitch and thus gives a high image quality. This is especially good for indoor devices, because there is less viewing distance.

Constantly evolving in terms of brightness and durability, SMDs are increasingly being used outdoors as well.


Most used:

- 5050 SMD
- 3028 SMD

SMDs have a better heat conduction, as well as higher light output (high lumen flux). Thus, they have a longer lifespan - of about 50,000 hours (low lumen decrease) - than the DIP LEDs.

   

Video Wall

A video wall (or video wall, LED wall, LED wall, LED scoreboard, ect.) Is nothing more than a large digital display area for displaying video and image material.

Video walls can be used in a variety of ways. As perimeter advertising boards in sports stadiums, digital billboards, or for presentation purposes at trade shows and other events.

They are either composed of several displays (with a small web width) or of individual panels (seamless transition without a gap). In any case, the size of the entire video wall depends on the size of the individual displays and panels, and they can be arranged individually.

The intended use distinguishes between indoor and outdoor.

Indoor: Sichtabstand geringer – feinere Auflösung ist von Vorteil
Outdoor: Allwettertauglichkeit – Helligkeit und Kontrastverhalten wichtig

   

Viewing Angle

As well as the viewing distance, the angle of view (viewing angle) are taken into account. In stadiums, video walls have a viewing angle between 120° and 160°. For viewers outside of this angle, the image is no longer optimally displayed and looks distorted.

     

Viewing Distance

Each video wall has an ideal viewing distance.

This depends, among other things, on the size of the video wall. Everyone knows the effect of sitting too close to the screen in the cinema. In the first row you often have problems to perceive the whole picture. However, digital images always consist of individual pixels. This is similar to a mosaic. For LED walls, each dot is represented by one LED. These LEDs can have different sizes and distances to each other. If you come too close to the LED wall, you no longer see the overall picture, but the individual LEDs.

The larger the distance between the LEDs (pixel pitch), the larger the viewing distance should be. The values ​​given by us are recommendations. The minimum distance indicates how far away the viewer should be at least, in order to be able to see the entire image well. The maximum distance tells you how far you have to go to be able to see the wall well. Of course, this is always a relatively subjective assessment and not least dependent on the eyesight of the beholder.

     

Virtual Pixel

With virtual pixels, a much finer image appearance can be achieved with a larger pixel pitch. The software control calculates the image based on 4 LEDs per pixel (instead of 3 LEDs) with an additional red diode. This creates virtual pixels (not physically existing ones).