How to choose the right COB small pitch LED display products?

LED semiconductor lighting network in recent years, the development of small-pitch LED display is very fast, LED small spacing has been widely used in intelligent monitoring, high-end conferences, studios and other fields. There are many types of LED small pitch products on the market. COB LED small pitch products are a new product that has recently emerged. Many people are very strange about the concept of COB and small pitch. It is often unknown to buy a display screen. So, how to choose the right COB small pitch LED display products?

1, select the screen size according to the viewing distance

The limit of view of the human eye is about 150 degrees in the vertical direction and 230 degrees in the horizontal direction. If the screen is in this range of view, it will give us an immersive feeling. But the angle is too big, the eyeballs need to keep following the video while watching, and it will be fatigued and dazzled for a long time. In fact, when the vertical angle of view of the image is 20 degrees and the horizontal angle of view is 36 degrees, there is a very good sense of visual presence, and it is not caused by frequent turning of the eyeball.

The viewing distance and screen size can be roughly selected using the formula below. (16:9 screen size is column)

Maximum screen size (inches) = viewing distance (cm) ÷ 3.736

Minimum screen size (inches) = viewing distance (cm) ÷ 6.227

3.4m<90 inch<5.6m

4.1m<110 inch<6.9m

5m<133 inch<8.3m

6.2m<165 inch<10m

Know the distance, the distance of the screen width [(L/ 3.3736) / 1.1473] *0.0254> D> [(L/6.227)/1.1473]*0.0254

2, select the pixel spacing according to the viewing distance

The reciprocal of the angle of view θ (resolution angle) of the nearest two points that the human eye can distinguish from the observed scene (image) is called the resolution of the human eye.

From a physiological point of view, when the human eye observes a still image at medium and medium relative resolution, the resolution angle θ is about 1 minute to 1.5 minutes, which can be calculated from the mathematical point of view:

L=3438*d (mm) and L=3438*d/1.5=2292d (mm)

[L=3438*d/2=1719d (mm)]

d/(2*3.1416*L)= θ /(360*60)

θ = 3438 * d / L resolution = 1 / θ.

When observing still images at medium and medium relative resolutions, θ is approximately 1 minute to 1.5 minutes.

P1.58 best viewing distance: 5.4m>p1.58>3.6m

P1.875 optimal viewing distance: 6.5m>p1.875>4.3m

P1.9 best viewing distance: 6.6m>p1.9025>4.4m

P2.37 best viewing distance: 8.1m>p2.37>5.4m

P2.5 optimal viewing distance: 8.6m>p2.5>5.7m

The pixel pitch of the liquid crystal display panel is about 0.6 mm.

LCD viewing distance: 2.06m>p0.6>1.37m.

3, viewing distance and character height relationship

The maximum line of sight does not have the spatial color mixture distance and the overall integrity of the display information, so the maximum distance can be accurately recognized as long as the smallest distance between the displayed minimum symbol and the text can be accurately recognized. Especially for text-based display screens, the definition of maximum line of sight has important application guidance.

The measurement of the maximum line of sight is based on the character height. The most common rule standard is:

Maximum viewing distance: L=1.58mm*8 (one character 8 pixels high)*600=7.58m

L=1.875mm*8*600=9m L=1.9025mm*8*600=9.1m

L=2.37mm*8*600=11.4m L=2.5mm*8*600=12m

The pixel pitch of the liquid crystal display panel is about 0.6mm, and the liquid crystal optimal viewing distance is:

Maximum line of sight: L = 0.6mm * 8 (a text 8 pixels high) * 600 = 2.88m