1. Strip screen
The strip screen is a rectangular screen composed of unit boards. It is also used to display text information. It can display text from left to right or from top to bottom. The most common display is from left to right. It is divided into single color, double color, indoor and semi-outdoor specifications. Indoor strip screens are used in places with dim light, such as airports, stations, hospitals, banks and other enterprises and institutions waiting for passengers or service halls to announce text information; semi-outdoor strip screens are mostly used in buses, house corridors, halls, bars and other bright places. A complete strip screen should include display body, power supply, control card and frame.
Unit board: The most common specifications of display unit board are: Φ 5 (244*488, 122*488), Φ 3.7 (152*304, 76*304). For specific specifications, see the indoor single and double color screen quotation table.
Dot matrix module: The specifications are divided into 788 (Φ 1.9), 1388 (Φ 3.0), 1588 (Φ 3.7), 1988 (Φ 4.8), 2388 (Φ 5.0). The commonly used ones are 1388, 1588 and 2388. It can also be divided into ordinary brightness, high brightness and super high brightness.
Frame: The thickness of the strip screen frame: the small screen frame (the screen body only displays one line of text is called a small screen) is 20mm; the large screen frame: (the screen body can display more than two lines of text is called a large screen) is 36mm. The large screen frame is ￥ 100.00 yuan/meter; the small screen frame is ￥ 85.00 yuan/meter, and the frame corner is ￥ 8.00 yuan/piece.
Power supply: The display screen commonly uses a 5V30A power supply, which has a power of 5V*30A = 150W. The power consumption of a Φ 5 unit board is 25W. Theoretically, one power supply can drive 6 unit boards. For the safety of the display screen, we also use one power supply with 5 unit boards. The Φ 3.7 specification can also be calculated in this way.
How to calculate the strip screen product required by the customer: Take the strip screen with a size of 0.3*1.5 (unit is m) required by the customer as an example. The calculation is as follows: For this size, the splicing of Φ 5 unit boards is closer to the requirements. Use three Φ 5 unit boards. The net size of the display is 0.244*1.464, and the frame thickness is 72mm (large screen frame). The total size of the strip screen can be calculated to be 0.316*1.536. It can meet the needs of customers well.
Products of other specifications are also calculated in this way.
2. Indoor and outdoor display screens
Single lamp
A single lamp is an LED light-emitting diode, which is a basic unit of LED display screens. It has perfect circle and oval, colored and colorless, transparent and colorless, with card and without card, with cap and without cap, flashing color, etc. It is used for various indications, displays, decorations, backlights, lighting and lighting. The white and white are best when the ratio of red, green and blue used in the display screen is 1:2:0.38 (in addition: red + green = yellow display).
Display screen
Display screen is a large screen used to display text, images, animations and other information. It is also divided into indoor and outdoor specifications, including single, dual-color and full-color. Among them, the indoor screen types include dot matrix single and dual-color screens, surface-mounted full-color screens, and full-color curtain wall screens; outdoor screens include single and dual-color semi-outdoor screens, outdoor single-color, dual-color, and full-color screens.
The composition of the display screen is the same as that of the strip screen, which is assembled from unit boxes one by one, but it is much more complicated than the strip screen, and the box is composed of modules one by one. A complete display screen consists of a unit box, a back cover, a fan, a power supply, an operating card, and a connecting U-shaped frame. The back cover and power supply are already configured when the full-color box leaves the factory, and the back cover of the single-color and double-color boxes needs to be configured according to customer requirements.
Driving mode: Scanning can reduce the number of chips and power consumption, and the brightness of the screen will also be reduced. Static driving is just the opposite. Similarly, outdoor screens are mostly statically driven and 1/4 scanned, while indoor screens are mainly 1/8 and 1/16 scanned.
Calculation of power consumption and brightness of lights in display screen:
Power: The power of one light is 5V20mA=0.1W, so the theoretical peak power consumption of a full-color screen with 3906 static points, two red, one pure green and one blue per square is: 3906*4*0.1=1.56KW. If it is 1/4, 1/8, 1/16 scanning, 4, 8, 16 should be divided from the total power to get the power consumption of the screen, and then the number of power supplies required is calculated on the power obtained (the power of one power supply is 150W).
Brightness: The overall brightness of the screen is integrated from the brightness of a single lamp. For example: 3906-dot 2R1PG1B (1/4 scan) outdoor full-color screen, Dalian Lumei tube core, the red tube brightness is 800mcd, the green tube brightness is 2300mcd, and the blue tube brightness is 350mcd. From this, a square theoretical brightness can be calculated as (800*2+2300+350) *3906/1000/4=4150cd.
Control card: The strip screen is controlled by an asynchronous card like the single and double color screen, and the full color display screen uses a universal grayscale synchronous control card. Type I card: for strip screens; Type II card: for single and double color screens; grayscale card: for full color screens. Detailed information can be obtained from relevant control card professional manufacturers.
In the LED industry, the relationship between the number of dots (i.e., pixels) and the dot spacing is as follows:
PH4=62500 dots PH4.7=44300 dots
PH6=27800 dots PH8 =15625 dots
PH10=10000 dots PH11.5=7500 dots
PH12=6400 dots PH12.5=6400 dots
PH16=3906 dots PH20=2500 dots
PH25=1600 dots PH31.25=1024 dots
PH37.5=711 dots PH40=625 dots
PH45=495 dots P50=400 dots
LED wavelength range:
Red: 625-630nm
Yellow-green : 568-572nm
Pure green: 520-530nm
Blue: 460-470nm
Yellow: 585-590nm
In addition, the indoor display screen (curtain wall screen) is directly installed on the wall by the light board without a cabinet.