What need to be considered when deciding the size of the LED display?
1) What is the minimum watching distance and then decide the size of the display according to the actual space.
2) Pixel pitch and resolution
3) The space for installation and maintainence
4) The angle from the display to the ground
What content do you want to show?
1) Text. Based on the size of the text and the resolution need.
2) Normal video.320 x 240 dot matrix
3) Number standard DVD display: ≥640 x 480 dot matrix
4) Complete computer video: ≥800 x 600 dot matrix
What are the requirements for the led display brightness according to the Environmental brightness?
General requirement for the brightness are as follows:
2) Semi indoor: >2000CD/㎡
3) Outdoor( not under sunshine):>4000 CD/㎡
4) Outdoor(under sunshine):>8000CD/㎡
Requirement for the brightness of RED, GREEN and BLUE when show white.
RED, GREEN, BULE plays different role when showing white. The fundamental reason is due to the human eye retina has different feeling for different wavelengths of light. After a large number of experiments and rest, we come to the following ratio for the reference: Simple red-green-blue light ratio: RGB 3:6:1 accurate brightness ratio: 3.0:5.9:1.1
Why the high quality led screen requires pure green led?
In the production of the led screen, we should use the trichromatic LED lamp with high lunimous efficiency and rich color. So that in the chromaticity diagram of color in the triangle area and near the tongue as far as possible in the color spectrum curve, to meet the needs of rich color and the issue of sufficient brightness and the tongue-shaped curve for the 515nm wavelength of light best, so high-end LED screen selected wavelength close to 515nm pure green LED light pipes, such as the choice of 520nm, 525nm or 530nm wavelength LED light tube.
Why choose DVI graphics card standard interface?
1) DVI graphics card interface is in line with international standards for the computer interface
2) No need to open the chassis, can be easily installed;
3) High-memory and strong dynamic screen display capability
4) Good compatibility of hardware and software
5) Supports all operating systems and application software
6) High-volume production, low cost, easy maintenance.
Can the display be controlled with Laptop?
The display can be controlled by the laptop with DVI port. DVI port is necessary.
Why it takes longer time to produce outdoor display?
1) procurement of raw materials: purchasing the led takes long time, specially when you have to import , it takes even longer time.
2) the complexity of production process: subject to PCB design, production casing, irrigation plastic, tune white balance, etc.;
3) the structure of demanding: the general design for the box, need to consider wind, rain, lightning and so on.
How to help customers choosing the right display?
1) what need to be shown?
2) viewing distance and viewing angle
3) resolution requirement
4) requirement of environment
5) cost control
What is the genaral ratio of width and hight for the display?
Picture and text: subject to what you want to show.
Video display: normmaly it is 4:3 or near this proportion. Ideal proportion is 16:9
How many pixels can one control system control?
For one linsn sending cards:
Communications screen Card A: single color, dual color 1024 x 64
Communications screen Card B: single color: 896x512, two color;896x 256
DVI dual color display: 1280x768. DVI full color led display: 1024x512
What are the factors to consider when design the size of the screen?
When design the size of the display, there are 3 factors very important.
1) the needs of displaying content
2) space limitation
3) according to the module size and resolution
Indicators display power consumption and power requirements of what?
Screen is divided into the average power consumption of the power consumption and maximum power consumption. Also known as the work of the average power consumption is usually the actual power consumption. Power consumption is the largest start-or full-bright at the time of extreme circumstances, such as power consumption, maximum power is AC power supply (wire, switches, etc.) must take into account the elements. Average power consumption is generally the largest power of 1/3. Display is a large-scale precision electronic equipment, safe use and reliable to work, its power supply input AC220V or AC220V power supply connected to the computer¡¯s input must be grounded. Note: The computer¡¯s power supply input AC220V grounding terminal connected with the computer chassis.
Display of the installation requirements?
power supply wiring should be in the body size of the screen 220V electricity power supply, FireWire grounding line 0 line; 380V electricity supply, the three 10-line ground line of fire line; the front lines with the 0-line the same wire cross-sectional area; more than 10 kilowatts buck should start screen equipment.
Communication distance is long for the definition of communication. Installed to display the type of communication lines used by the length of the standard to install communications lines. Prohibition of communication lines and power lines in the same pipe line alignment.
About the level of the installation screen, do not allow the dumping after the lifting rod to regulate the installation of up and down before the installation of wall mounted hook falling forward landing position to increase support for the installation of bolts.
What issues should be considered for outdoor screen design and installation?
The main issues of outdoor screens are as follows:
1) Screen installed in the outdoor sun and rain often, the wind dust cover, the work environment. Electronic equipment to be wet or damp can cause serious short-circuit or even fire, and even lead to failure of fire, resulting in losses;
2) Screen may be caused by strong electric lightning attack Magnetic;
3) Significant changes in ambient temperature. Display the work itself should have a certain amount of heat, if the ambient temperature and the heat is too high and non-performing, integrated circuits may not work correctly, and even burned down, so that shows that the system does not work;
4) Wide audience, require line-of-sight distance requirements of wide field of vision; ambient light changes, in particular, may be subject to direct sunlight.
The special requirements of the above, outdoor display must be:
1) Screen body and the screen body and architecture must be strictly waterproof junction leakage; screen body in order to provide good drainage measures, in the event of a smooth water emissions; (2) and building on the screen to install lightning protection devices. The main screen and the casing to maintain a good grounding, grounding resistance is less than 3 ohms, so that high current caused by lightning discharge in time;
3) The installation of ventilation to cool the screen so that the internal body temperature of -10 ℃ ~ 40 ℃ between. Screen behind the body above the axial fan is installed, from the heat;
4) Choice of working temperature -40 ℃ ~ 80 ℃ industrial level integrated circuit chip, the temperature is too low to prevent the winter so that the screen could not be activated. ;
5) In order to ensure a strong ambient light in the case of remote visualization, we must choose ultra-high brightness light-emitting diodes;
6) Shows that the new optional wide angle medium tube, wide angle, color pure, consistent coordination, more than 100,000 hours life. Show that the outer packaging for the media the most popular along with over a square cylinder, silicone sealed, non-metal assembly; its refined aesthetic appearance, sturdiness and durability, with the anti-direct sunlight, dust-proof, waterproof, anti-high temperature, anti-short-circuit the "Five Anti" feature.
Whole screen does not work (black screen)
1) Check power supply
2) Check signal connection (cat5,DVI cable) (synchronous screen)
3) If synchronous screen, check the green led of sending card and receiving card whether it is twinkling or not.
4) Check the monitor of PC whether it is protected as black,or screen display area is black or pure blue. (Synchronous screen)
Whole LED module does not work (black module)
1) Successive modules in horizontal do not work, please check the ribbon cable between the normal unit module and unnormal unit module whether it is connectted or not, or replace the first module from right side when facing the screen.
2) Successive moudels in vertical do not work,please check the power supply of all the modules.
One row lamps of module does not work.
1) Check this row whether connecting to output pin of 4953.
2) Check 138 encoder.
3) Check 4953.
4) Check Vcc and GND of 4953.
5) Check output of 74HC138 and 4953's controlling pin whether connectted or not.
Unit module doesn't work.
1) Check 595 normal or not.
2) Checking the up and down moudle corresponded common pin connect or not.
3) Check 595 output pin to moudle pin connect or not.
One color lacked in half or whole LED panel.
1) Check 245 R, G, B data output.
2) Check normal 595 output pin and unmormal 595 input pin whether it is connectted well or not.
What is the difference of SMD and DIP ?
SMD also named SMT (surface mounted technology),through the SMT technology encapsulating diode, soldering this lamp on the PCB board surface. Widely used for indoor projects.
DIP LED are throught the DIP ( Dual in-line package) technology, after soldering the LED lamp’s feet to stable it on the PCB., so it names of DIP LED. Mainly used for outdoor projects.
The comparison of SMD and DIP.
SMD with RGB 3 colors in 1 LED cup technology, with better colors uniformity, and wider viewing angle, usually, SMD can be done the small pitch pixels, so for some high resolution LED screen, SMD is the best choice.
DIP technology with LED feets in PCB board, then the heat dissipation is better than SMD, and higher brightness, even under the sunshine, DIP LED screen can also show the contents well. That is the reason why people like DIP for outdoor used.
For the energy saving influence, SMD is a new technolog, with high luminous efficientcy.compare
With DIP,it is 30% energy saving.