In today's era of high-tech development, the emergence of flexible scrolling LED displays is a reflection of current technological progress. It can achieve arbitrary curved changes in the screen's up, down, left and right, meeting various irregular needs in reality, and is ideal for places such as shopping malls, street advertising, corporate meeting rooms, exhibition halls, and large classrooms in schools.
In the LED display field, "viewing angle" is one of the standards for evaluating the quality of a LED display product.
The viewing angle of a rolling LED screen refers to the angle at which the user can clearly see all the content on the screen from different directions. The viewing angle can also be understood as the maximum or minimum angle at which the image can be seen clearly.
Although, the viewing angle is only a reference value. However, in general, the rolling LED screen display screen view angle has two indicators: horizontal and vertical.
For example, the general LED display technical parameters have this description (viewing angle: 140°/140°); this means that the Z viewing angle is 140°, and the horizontal and vertical Z viewing angle is 140°. If you exceed 140°, you either have a bad viewing angle or a blind spot.
The horizontal viewing angle indicates the vertical normal of the rolling LED screen (i.e. the vertical hypothetical line of the LED display). The display image can still be viewed normally at a certain angle perpendicular to the left or right side of the normal. This angular range is the horizontal viewing angle of the rolling LED screen. Similarly, when using the horizontal normal as a reference, the up and down viewing angle is called the vertical viewing angle. Generally speaking, the viewing angle is based on the change in contrast. The greater the viewing angle, the lower the contrast of the displayed image seen from that position. When the angle is increased to a certain point and the contrast ratio reaches 10:1, this angle is the size viewing angle of the rolling LED screen.
The larger the viewing angle the better, but the size of the viewing angle is mainly determined by the way the tube core is encapsulated, so the viewing angle is largely determined when encapsulating the tube core, this depends on the flexible scrolling LED display manufacturer.
Viewing angle and distance, but now the rolling LED screen manufacturers are unified, in the production process are designed in accordance with the prescribed distance, the same chip, the larger the viewing angle, the lower the brightness of the rolling LED screen.
Grayscale is one of the very important parameters in the process of using the rolling LED screen. Grayscale, also known as halftone, is mainly used for transmitting pictures with 16, 32 and 64 levels respectively. It uses matrix processing to process the pixels of the file into 16, 32 and 64 levels in order to make the transmitted image sharper. To display an image or animation, whether on a monochrome, bicolor or tricolor screen, it is necessary to adjust the grayscale of the light emitted by each of the LEDs that make up the pixels, and the fineness of the adjustment is often referred to as grayscale.
Change the current flowing through them
Change the current flowing through the LEDs, generally allow continuous working current of about 20 mA, in addition to the LEDs appear red saturation phenomenon, other LED gray scale is basically proportional to the current flowing through.
Adjust the pulse width
We can use the visual inertia of the human eye, the use of rolling LED screen pulse width modulation method to achieve grayscale control, that is, periodically change the width of the light pulse (i.e., duty cycle). As long as the repeated lighting cycle is short enough (i.e., refresh frequency is high enough), the human eye will not feel the jitter of the light-emitting pixels.