Ningbo Yejin Supply Chain Management Co.,Ltd , https://www.car-parts-accessories.com
Â
Â
Â
 
1.LED is the LIGHT EMITTING DIODE. The LED in the display industry specifically refers to the LED that can emit the visible band.
2. What is a pixel?
The smallest luminous unit of the led display has the same meaning as the pixel in the ordinary computer monitor.
3, what is the pixel pitch (point spacing)?
The distance between the centers of two adjacent pixels, the smaller the distance, the shorter the visual distance. The person in the industry usually abbreviates P to indicate the dot pitch.
4, what is the pixel density?
Also known as dot density, usually refers to the number of pixels per square meter of display.
5, what is the LED display module?
A minimum unit consisting of a number of display pixels that is structurally independent and can form a led display screen. Typical 8*8, 8*7 and so on.
6. What is DIP?
DIP is the abbreviation of DOUBLE IN-LINE PACKAGE, a dual-inline assembly.
7. What is SMT? What is SMD?
SMT is the surface mount technology (abbreviation of SURFACE MOUNTED technology) and is currently the most popular technology and process in the electronics assembly industry; SMD is a surface mount device (abbreviation for surface mounted device).
8, what is the LED display module?
A basic unit that has a circuit and a mounting structure, has a display function, and can realize a display function through simple assembly.
9, what is the led display?
Through a certain control method, a display screen composed of LED device arrays.
10. What are the advantages and disadvantages of a plug-in lamp module?
It refers to the DIP packaged lamp passing the lamp foot through the PCB board and filling the lamp hole with the solder. The module made by this process is the plug-in lamp module. The advantages are: high brightness and good heat dissipation. The disadvantage is that The pixel density is small.
11: What is a surface mount module? What are the advantages and disadvantages?
The surface mount is also called SMT. The SMT packaged lamp is soldered to the surface of the PCB board through the soldering process. The lamp leg does not need to pass through the PCB board. The module made of this process is called the surface mount module. The advantage is that the display effect is good. Pixel density, suitable for indoor viewing: The disadvantage is that the brightness is not high enough, the lamp itself is not good enough for heat dissipation.
12. What is a sub-adhesive module? What are the advantages and disadvantages?
Sub-SMT is a product between DIP and SMT. Its LED lamp has the same package surface as SMT, but its positive and negative pins are the same as those of DIP. It is also soldered through the PCB during production. The advantages are: high brightness and good display effect. The disadvantages are: complicated process and difficult maintenance;
13. What is 3 in one? What are its advantages and disadvantages?
It means that the SMT lamps encapsulated by three different colors of LED chips of different colors are vertically aligned along a certain distance. This not only has all the advantages of 3-in-1, but also can solve various shortcomings of 3-in-1: the process is complicated and maintenance is difficult. .
14, what is the three and one?
The RGB three individually packaged SMT lamps are vertically juxtaposed at a certain distance, which not only has the advantages of 3-in-1 but also solves the various shortcomings of 3-in-1.
15, what is a dual-color, pseudo-color, full-color display?
Through different colors of light-emitting diodes can form a different display, dual-color is composed of red, green or yellow-green color, pseudo-color is composed of red, yellow-green, blue three different colors, full-color is from red , pure green, pure blue three different colors.
16: What is the brightness?
The light intensity emitted by a led display unit area is expressed in units of CD/square meter, which is simply the light intensity emitted by a square meter display;
17: What is the brightness level?
The number of manually or automatically adjusted levels from full-brightness to full-brightness.
18, what is the gray level?
At the same brightness level, the number of technical processing levels from the darkest to the brightest
19, what is the maximum brightness?
Under a certain ambient illumination, the primary colors of the led display screen are at the maximum brightness and maximum gray scale;
20. What is Moire?
It is when shooting a full-color LED display at work that irregular water ripples appear on the led display screen. These water ripples are called “moles†in physics.
21, what is the PCB?
PCB is (printed circuit board abbreviation) printed circuit board
22. What is a cell board specification?
Refers to the size of the cell plate, usually expressed as a unit cell length multiplied by a wide expression, in millimeters. (48×244)
23, what is the resolution of the cell board?
Refers to how many pixels a cell board has, which is usually expressed by the number of rows of cell plate pixels multiplied by the number of columns. (eg: 64×32)
24. What is BOM?
BOM is (bill of material) BOM
25: What is white balance and what is the white balance adjustment?
What we call white balance refers to the white balance, which is the balance of the brightness ratios of the three RGB colors; the RGB three-color brightness ratio and the adjustment of the white coordinates are called white balance adjustments;
26: What is contrast?
Under a certain ambient illumination, the ratio of the maximum brightness of the led display to the background brightness.
27, what is the color temperature?
When the color emitted by the light source is the same as the radiated color of the black body at a certain temperature, the temperature of the black body is referred to as the color temperature of the light source.
28, what is the color difference?
The led display consists of three combinations of red, green, and blue to produce a variety of colors. However, these three colors are made of different materials. The viewing angle is different. The spectrum distribution of different LEDs are all changed. These differences that can be observed are called It is color difference. When observing the LED at a certain angle, the color of the LED changes, and the ability of the human eye to judge the color of the real picture (such as a movie picture) is better than that of the observation computer.
29. What is the frame change frequency?
The number of updates of the display screen information per unit time;
30. What is the refresh rate?
The number of times the display screen is repeatedly displayed in the display unit per unit time;
31: What is the perspective? What is the perspective? What is the best perspective?
The viewing angle is when the brightness of the viewing direction drops to 1/2 of the brightness of the normal to the led display screen. The angle between the two observation directions and the normal direction of the same plane. It is divided into horizontal and vertical viewing angles; the viewing angle is the angle between the direction of the image content on the display screen and the normal of the display screen. The best perspective is to be able to just see the contents of the display, and not flat, the angle between the direction of the clearest image content and the normal;
32: What is the best line of sight?
It is the vertical distance from the screen body that can exactly see the contents of the display screen, and is not flat and the most clear image content is relative to the screen body:
33: What is the out of control point? Several kinds?
Pixels that do not correspond to the lighting state and control requirements are divided into three categories: blind spot (also known as dead point), and constantly bright spot (or dark spot) flash point;
34, what is the static drive:? What is a scan driver? What is the difference between the two?
The "point-to-point" control from the output pin of the driver IC to the pixel is called static drive. The "point-to-column" control from the output pin of the driver IC to the pixel is called scan drive. He needs to control the circuit from: The driver board can be clearly seen: static drive does not need to control the circuit, the cost of teaching, but the display is good, good stability, brightness loss, teaching, etc.; scan drive it requires line control circuit, but the low cost, display Poor results, loss of brightness, etc.;
35. What is constant current drive? What is a constant voltage drive?
Constant current refers to the constant current output value specified in the allowable operating environment of the driver IC: Constant voltage refers to the voltage value specified in the constant output design within the allowable operating environment of the driver IC.
36, led display general aspect ratio is how much?
Graphic screen: Determined according to the displayed content; video screen: generally 4:3 or close to 4:3; ideal ratio is 16:9.
37, a control system can control the number of points?
Communication screen A card: monochrome, dual color 1024×64; communication screen B card: monochrome: 896×512 double color: 896×256; DVI dual color screen: 1280×768; DVI full color screen: 1024×512
38. What is a nonlinear correction?
If the digital signal output by the computer is displayed without correction on the led display, color distortion will occur. Therefore, in the system control circuit, the signal output from the original computer is calculated through a non-linear function to obtain the signal required by the display. Because the front and rear signals are nonlinear, we often call it a nonlinear correction.
39. What is the rated operating voltage? What is the operating voltage? What is the supply voltage?
The rated working voltage refers to the voltage when the voltage is working normally; the working voltage refers to the voltage value of the electric appliance within the rated voltage range during normal operation: the supply voltage is divided into AC and tributary supply voltages, and our actual AC supply voltage is both AC220V---240V, DC supply voltage is generally 5V DC12V Solar power supply is generally 12V
40. What is color distortion?
It means that the same object is displayed in nature and on the display, both of which have differences in the visual sense of the human eye.
41: What is a synchronous system and what is an asynchronous system?
Synchronous and asynchronous are relative to what the computer says. The so-called synchronous system refers to the led display control system that is displayed in synchronization with the display on the display screen of the computer. The asynchronous system means that the display data edited by the computer is stored in advance. In the display control system, the shutdown of the computer will not affect the normal display of the led display. Such a control system is an asynchronous control system.
42, what is the blind spot detection technology?
Through the upper software and the underlying hardware, the blind spot on the display (LED open circuit and short circuit) can be detected and a report can be formed to inform the LED screen administrator. Such a technology is called blind spot detection technology;
43, what is the power test?
Through the upper software and the underlying hardware, the working status of each power supply on the display screen can be detected, and a report can be formed to tell the LED panel manager. Such a technology is called power detection technology.
44, what is the brightness test? What is brightness adjustment?
The brightness in the brightness detection refers to the brightness of the environment in which the led display screen is located. Through the light sensor, the brightness of the display screen is detected. This detection method is called brightness detection; the brightness in the brightness adjustment refers to the led display screen. The brightness sent out, the detected data feedback to the led display control system or control computer, and then adjust the brightness of the display according to this data, called brightness adjustment;
45. What is a real pixel? What is a virtual pixel? What are the virtual pixels? What is pixel sharing?
The real pixel refers to the relationship between the number of physical pixels on the display screen and the actually displayed pixels. The actual number of points on the display screen can only show how many points of image information. The virtual pixel refers to the relationship between the physical pixel number of the display screen and 1:N (N=2, 4) of the actually displayed pixel points. The image pixels that can be displayed are 2 or 4 times more than the actual pixels of the display screen. Pixels can be divided into virtual modes according to their virtual modes: software virtual and hardware virtual: divided into 2 times virtual and 4 times virtual according to multiple relations, and divided into 1R1G1B virtual and 2R1G1B virtual according to the mode of row lights on a module;
46. ​​What is remote control? Under what circumstances?
The so-called remote is not necessarily a long distance. The remote control includes the main control end and the controlled end in a local area network, but the space distance is not far; and the main control end and the controlled end are in two kinds of distances within a relatively long distance. The customer request or according to the customer control position exceeds the optical fiber directly Control distance, then use remote control;
47. What is fiber optic transmission? What is a cable transmission?
Optical fiber transmission is the use of transparent glass fiber for the transmission of electrical signals into optical signals. Transmission of electrical wires is the use of metal wires for the direct transmission of electrical signals.
48, under what circumstances with network cable? Under what circumstances with fiber?
When the distance between the display screen and the control computer is less than 100 meters, the cable is used for transmission. When the distance between the two is less than 500 meters and greater than 100 meters, the multimode optical fiber is used. When the distance is more than 500 meters, the single-mode optical fiber is used.
49. What is LAN control? What is Internet Control?
In a local area network, through a computer to control another computer or connect to other external devices, the main controller achieves the purpose of control through the IP address of the controller in the INTERNET network, which is called Internet control;
50. What is DVI? What is VGA?
DVI is the abbreviation of Digital Video interface, namely digital video interface. It is now a universal digital video signal interface.
51. What is a digital signal? What is a digital circuit?
The digital signal means that the amplitude of the signal is discrete, the amplitude is limited to two finite values ​​of 0 and 1, and the circuit for processing and controlling the west signal is called a digital circuit.
52, what is the analog signal, what is the analog circuit?
Analog signal means that the value of signal amplitude is continuous in time; the circuit that processes and controls this signal is called analog circuit.
53. What is a PCI slot?
The PCI slot is an expansion slot based on a PCI local bus (PEDPHERD component interconnect). The PCI slot is the main expansion slot of the motherboard. By plugging in different expansion cards, almost all external functions that the computer can achieve can be achieved:
54, what is the AGP slot?
Accelerated graphics interface. AGP is an interface specification that can be displayed at a faster speed on ordinary personal computers using 3D graphics. AGP is an interface designed to transfer 3D graphics faster and more smoothly. He uses the main memory of an ordinary personal computer to refresh the images displayed on the monitor, and supports 3D graphics technologies such as texture mapping, zero buffering, and alpha blending.
55. What is GPRS and what is GSM? What is CDMA?
GPRS is a new bearer service developed on the existing GSM system through the packet radio service (General Packet Radio Service), which is mainly used for radio communication; GSM is the “Global System For Mobile†unifiedly launched by the European Standardization Committee in 1992. "Abbreviation for Communication" (Global System for Mobile Communication), which uses digital communication technology and a unified network standard to ensure the quality of communications and to develop more new services for users. CODE DIVISION MULTIPLE ACCESS: A new and mature wireless communication technology based on spread spectrum technology.
56. What is the use of GPRS technology for display screens?
In the GPRS data network based on mobile communication, the data of our LED display screen is used for data communication through the GPRS transceiver module, which can realize remote point-to-point small-scale data transmission, achieving the purpose of remote control;
57, what is the USB interface
The English acronym for USB is UNIVERSAL SERIALBUS, translated into Chinese: Universal Serial Bus. Also known as Universal Serial Interface, it supports hot-plugging and can connect up to 127 PC external devices: USB 1.0 and USB 2.0 interface standards.