Anyone starting to research an indoor LED display quickly runs into a wall of terms: P1.5 and P2.5, COB and SMD, 500×500 cabinets and 16:9 cabinets, all-in-one screens at 163 inches. These are not minor technical details. They determine image quality, the right viewing distance, the final size that can actually be built, and the overall cost of the project. This guide walks through the differences in a structured way so that your decision rests on a clear understanding.
1. How an Indoor LED Display Is Built
Unlike an LCD screen, an LED display is not a single panel. It is assembled from smaller units on three levels:
Pixel: A single light point made up of three light-emitting diodes: red, green and blue. Mixing their output produces every colour in the image.
Module: A circuit board carrying a fixed number of pixels. It is the smallest replaceable unit during maintenance. Common sizes include 320×160 mm, 250×250 mm and 300×168.75 mm.
Cabinet: A metal frame, usually die-cast aluminium, housing several modules along with the receiving card and power supplies. Cabinets are joined side by side to form the finished display.
This structure matters because the final size of any LED display must be a multiple of the cabinet size. You cannot build a screen 3.15 m wide from 500 mm cabinets; the nearest options are 3.00 m or 3.50 m.
2. Pixel Pitch: The Single Most Important Number
The figure after the letter P, such as P1.5 or P2.5, is the distance in millimetres from the centre of one pixel to the centre of the next. The smaller the number, the higher the pixel density and the sharper the image, and the higher the price.
| Category | Pixel Pitch | Pixels per m² (approx.) | Comfortable Viewing Distance | Typical Applications |
|---|---|---|---|---|
| Ultra-fine | P0.9 – P1.2 | 700,000 – 1,200,000 | 1 – 3 m | Control rooms, boardrooms, broadcast studios |
| Fine | P1.5 – P1.9 | 280,000 – 440,000 | 1.5 – 5 m | Meeting rooms, lobbies, sales galleries |
| Standard | P2.5 | 160,000 | 2.5 – 7 m | Showrooms, retail stores, event halls |
| Economy | P3 – P4 | 62,500 – 110,000 | 3.5 m and beyond | Mosques, large halls, high interior walls |
A practical viewing-distance rule: the closest acceptable distance in metres is roughly equal to the pitch in millimetres. A P2.5 display can be viewed comfortably from about 2.5 m, while the ideal distance is two to three times that figure. Any closer and viewers begin to see individual pixels.
It follows that specifying P1.2 for a screen viewed from 8 metres is money spent where it isn’t needed, and choosing P3 for a small meeting room gives an image that is uncomfortable to look at.
3. LED Packaging Technologies: SMD, GOB and COB
These differ in how the LEDs are mounted on the module and protected, which directly affects durability and viewing experience.
SMD (Surface Mounted Device)
The most widespread technology. Each pixel is a small package soldered onto the board surface. It offers good value and easy maintenance, but the LEDs are exposed and can be damaged by knocks during installation or cleaning, especially at fine pitches.
GOB (Glue On Board)
SMD with a layer of clear resin poured over the module. The layer protects the LEDs from impact, humidity and dust, and reduces reflections. A good fit for places where people get close to the screen or touch it, such as retail stores and exhibitions.
COB (Chip On Board)
The LED chips are bonded directly to the board and sealed under one continuous layer. The result is a smooth, very robust surface with higher contrast, wider viewing angles and lower heat. It is currently the preferred choice for ultra-fine pitches of P1.2 and below, and for control rooms running around the clock. It costs more, and servicing is usually done by replacing the whole module.
| Criterion | SMD | GOB | COB |
|---|---|---|---|
| Impact resistance | Low | High | Very high |
| Contrast and black levels | Good | Very good | Excellent |
| Suitability below P1.2 | Limited | Limited | Ideal |
| Ease of maintenance | High | Medium | Module replacement |
| Cost | Lowest | Medium | Highest |
4. Common Cabinet Sizes and Their Effect on Final Dimensions
The cabinet size dictates which dimensions can be built. The most common for indoor displays are:
500×500 mm and 500×1000 mm: Common in standard-pitch and rental/event displays. Flexible to configure, but they only produce an exact 16:9 ratio with specific cabinet counts.
600×337.5 mm (16:9 ratio): The most widely used standard today for fine-pitch displays in meeting rooms and control rooms. Any equal configuration, such as 4×4 or 6×6 cabinets, produces an exact 16:9 screen that fits video content with no black bars.
640×480 mm and 960×960 mm: Used in fixed-installation displays at standard and economy pitches. The larger size reduces cabinet count and installation time on big screens.
5. Calculating Resolution from Dimensions
The formula is simple:
Horizontal pixels = screen width in mm ÷ pixel pitch
Vertical pixels = screen height in mm ÷ pixel pitch
A screen 4,000 mm wide by 2,250 mm high at P2.5 gives 1600×900 pixels. The same screen at P1.5 gives roughly 2667×1500 pixels.
Since most content is produced in Full HD or 4K, it helps to know the size that delivers each resolution at each pitch:
| Pitch | Size for Full HD (1920×1080) | Size for 4K (3840×2160) |
|---|---|---|
| P0.9 (0.9375) | 1.80 × 1.01 m | 3.60 × 2.03 m |
| P1.2 (1.25) | 2.40 × 1.35 m | 4.80 × 2.70 m |
| P1.5 (1.5625) | 3.00 × 1.69 m | 6.00 × 3.38 m |
| P1.8 (1.875) | 3.60 × 2.03 m | 7.20 × 4.05 m |
| P2.5 | 4.80 × 2.70 m | 9.60 × 5.40 m |
The table highlights a point many people miss: a small screen with a large pitch will not reach Full HD. A P2.5 screen 3 m wide has a resolution of only 1200×675 pixels. That is fine for viewing from a distance, but not for spreadsheets or small text in a meeting room.
6. Types of Indoor LED Displays by Application
1. Fixed Installation
Mounted permanently on a wall with a steel substructure. The standard choice for halls, lobbies and control rooms. The key consideration is access: front-service displays can sit flush against the wall with modules removed magnetically from the front, while rear-service displays need a maintenance corridor behind them, typically at least 60 to 80 cm.
2. All-in-One LED Displays
LED screens in predefined sizes such as 108, 136, 163 and 216 inches, supplied with built-in control, speakers and mounting, and operated much like a very large TV. Ideal for meeting rooms because they install quickly with no custom engineering. For example, a 163-inch model is roughly 3.60 × 2.03 m at Full HD.
3. Rental and Event Displays
Lightweight cabinets with quick locks and handles, designed for repeated assembly and dismantling. They withstand transport, support flying and ground stacking, and are used at conferences, exhibitions and on stage.
4. Flexible Displays
Modules on soft, bendable boards used to wrap cylindrical columns, curved surfaces and creative shapes. They require a supporting structure made to match the surface.
5. Transparent Displays
Spaced LED strips that let viewers see through the screen, with transparency typically between 50% and 90%. Used on glass shopfronts and in exhibitions without blocking views or daylight.
6. Floor LED
Built to carry loads and be walked on; some models are interactive and respond to footsteps. Used in theatres, entertainment centres and immersive experiences.
7. Creative and Ceiling Displays
Special configurations such as ceiling screens that simulate the sky, corner screens, cubes and ribbon displays. They use the same cabinets with custom structural design and content.
7. Other Specifications That Make a Difference
Brightness: Indoors, 500 to 1,200 nits is sufficient. Excess brightness in an enclosed room strains the eyes and consumes more power for no benefit. Spaces with glass façades and strong daylight need the upper end of the range.
Refresh rate: Preferably no lower than 3,840 Hz, especially if the screen will appear on camera for broadcast or filming, as lower rates cause moving scan lines in recorded footage.
Grayscale: The higher it is, such as 14 or 16 bit, the smoother gradients appear at low brightness without banding.
Calibration: Quality displays undergo point-by-point factory calibration of every pixel so that no colour differences appear between cabinets.
Power consumption: Usually quoted as two figures, maximum and average. The average figure is the closer guide to the actual electricity bill; the maximum is the reference for designing the electrical supply.
8. How to Choose the Right Display: Practical Steps
- Define the nearest and farthest viewing positions. This sets the appropriate pitch range.
- Define the content type. Video and advertising tolerate a larger pitch; text, tables and data dashboards need higher resolution.
- Measure the available space accurately, then choose the closest size that results from cabinet multiples.
- Calculate the resulting resolution and check that it suits the content source.
- Decide on the maintenance method based on whether a rear corridor is available.
- Select the packaging technology according to audience proximity and continuous-operation requirements.
- Review power, ventilation and structural requirements before approving the location.
Conclusion
There is no universally “best” LED display. The right display is the one where pitch matches viewing distance, dimensions match cabinet multiples, technology matches the application, and resolution matches the content. When these elements are considered together, the result is a clear image, a well-planned budget and a display that performs reliably for years.
At Fast Vision, we help clients across all regions of Saudi Arabia select, design and install the right display, as an authorised dealer for global brands including Samsung, Barco, Absen, Hikvision and LG. For a consultation or a study of your project, contact us at yasser@fv.sa