HOME Case Studies COB Beta P1.5 Sand Table — Shanghai
Case Study 2025 · Shanghai, China

COB Beta P1.5 Sand Table Display in Shanghai

A corporate showroom operator in Shanghai needed an L-shaped immersive digital sand table — 9.6 meters wide, combining a 30.72 m² floor display with a 23.04 m² LED wall. The challenge: P1.5 SMD modules at this scale are notoriously fragile. Every assembly cycle risks dead pixels from finger pressure, tool contact, or crowd proximity. The solution? COB Beta's epoxy encapsulation — turning 1,050 modules into 1,050 impact-resistant boards that survive frequent teardown and rebuild without a single casualty. Driven by 3 × NovaStar MCTRL4K processors synchronized across 37 Ethernet ports.

Final design render of the 53.76-square-meter L-shaped P1.5 COB Beta sand table display and LED wall planned for Shanghai corporate showroom
Project Scope
53.76 m²
Floor 30.72 + Wall 23.04 · L-Shaped
Pixel Pitch
P1.5
COB Beta · 5H Hardness
Video Processor
3×MCTRL4K
+ Sync Card · 37 Ports
Total Pixels
≈24M
≈ 3 × 4K Resolution
Delivered by DOIT VISION Engineering Team · · Reviewed by Kris Liang, Co-Founder · August 2026
CE · EMC · RoHS
15 Engineers · 60-Person Shenzhen Team
55+ Countries · NovaStar · Colorlight
Contour PCB + FlexibleMooncell + ResolumePoka-Yoke Assembly
Project Overview

At a Glance

Client
Corporate Showroom Operator
Shanghai, China
Display Technology
P1.5 COB Beta
5H epoxy · Impact-resistant
Video Processors
3 × MCTRL4K
Sync card · 37 Ethernet ports
Structure
Magnetic Direct Mount
Zero custom cabinets
Protection
COB Epoxy Encapsulation
Zero SMD fragile lamp beads
Module Count
1,050 Modules
Floor 600 + Wall 450
Key Challenge
Frequent Assembly Cycles
SMD would fail · COB survives
Timeline
≈ 3 Weeks
Production → Installation
01 — The Brief

A 54 m² Sand Table Where Fine Pitch Meets Crowds

The question wasn't whether P1.5 could deliver the visual quality. It was whether P1.5 could survive the installation — and the re-installation after that.

A corporate showroom operator in Shanghai wanted an L-shaped digital sand table — 9.6 meters wide, consisting of a 30.72 m² floor display and a 23.04 m² LED wall rising behind it. The brief was straightforward: an immersive digital canvas where the floor layer renders GIS maps, floor plans, and 3D terrain models, while the vertical wall plays brand narratives synchronized with the sand table content.

But here's the rub: P1.5 at 54 m² means roughly 24 million pixels spread across 1,050 individual LED modules. Each module is a palm-sized board covered in tiny LED chips spaced 1.5 millimeters apart. At this density, a single LED die is barely visible to the naked eye — and just as fragile. SMD modules at P1.5 are notorious for losing pixels during assembly. A technician's fingertip pressing on the wrong spot, a screwdriver slipping, or modules stacked face-to-face during transport — any of these can shear off multiple LED chips in an instant.

And this client's showroom operates on a rotating exhibition schedule. The sand table would be assembled, disassembled, and reassembled multiple times. Each cycle with SMD would be a dice roll on dead pixel count. Each dead pixel requires removing the module, desoldering the broken chip, soldering a replacement, and recalibrating — a process that, repeated across a thousand modules, turns maintenance into a full-time job.

Macro close-up of COB Beta module epoxy encapsulation surface showing 5H hardness and smooth protective layer with coin size reference
02 — Material Decision

COB vs SMD: The Fragility Equation

SMD modules at P1.5 are precision optical instruments. The problem is they're treated like building blocks.

To understand why we specified COB Beta for this project, you need to understand what happens to an SMD P1.5 module during a single assembly cycle:

  • Finger PressureTechnicians handle modules by their edges during installation, but accidental contact with the LED surface is inevitable at scale. An SMD lamp bead at P1.5 measures roughly 0.5mm across — pressing a thumb onto the surface can crush multiple chips simultaneously.
  • Tool ContactDuring magnetic mounting or alignment, a screwdriver, pry tool, or even a fingernail can nick exposed SMD lamp beads. At P1.5 density, one slip can disable a cluster of 4–6 pixels.
  • Transport StackingModules are transported face-to-face with foam separators. SMD lamp beads protrude from the PCB surface; any pressure concentration during stacking — a grain of debris, an uneven foam sheet — creates a point load on the exposed chips.
  • Crowd ProximityEven after installation, the sand table sits in a high-traffic exhibition zone. Visitors lean over the display, point at details, and occasionally brush against the surface with watches, rings, or bags — all of which can damage exposed SMD chips.
Why COB Beta Eliminates These Risks

COB (Chip-on-Board) encapsulates every LED chip under a continuous layer of epoxy resin. The surface is a single, seamless, 5H-hardness shield — not thousands of individual exposed lamp beads. When a technician presses the surface, the force distributes across the epoxy plane. When a visitor's watch brushes against it, there's nothing to shear off. The module is effectively a solid-state optical panel, not a fragile PCB covered in bare micro-components. And critically, COB Beta delivers this durability at P1.5 — a pitch where SMD fragility becomes the dominant maintenance cost driver.

03 — System Architecture

3 × MCTRL4K Driving 24 Million Pixels

53.76 m² at P1.5mm pitch generates approximately 24 million pixels — the equivalent bandwidth of three simultaneous 4K streams running at 60Hz. A single standard LED sending card handles at most 8.84 million pixels (one MCTRL4K), so the math dictated a minimum of three units.

But raw pixel count isn't the only bottleneck. Each gigabit Ethernet output from a sending card maxes out at roughly 650,000 pixels under standard 8-bit/60Hz conditions. For 24 million pixels:

/* PIXEL-TO-PORT CALCULATION */
[1] Total pixels: 24,000,000
[2] Per-port capacity: ≈ 650,000
[3] Ports required: 24,000,000 ÷ 650,000 ≈ 37
[4] MCTRL4K ports: 16 per unit
[5] Units needed: 37 ÷ 16 ≈ 2.3 → 3 units
[6] Total ports: 3 × 16 = 48 (11 spare)

We deployed three NovaStar MCTRL4K processors with a sync card to maintain frame-level synchronization across all three units. The topology splits logically: two MCTRL4K units drive the floor sand table (30.72 m² ≈ 13.7M pixels), and the third handles the vertical LED wall (23.04 m² ≈ 10.2M pixels). The sync card ensures both surfaces display the same frame simultaneously — so when a camera pans across a 3D city model on the sand table, the brand video on the wall transitions in lockstep.

Why Not 2 × VX1000?

The NovaStar VX1000 supports up to 13 million pixels — theoretically two units could handle 24M. But at 12M per unit, both processors would run near their ceiling with zero headroom. Three MCTRL4K units at 8M each provide comfortable margin for future module additions, reduce single-point-of-failure risk, and cost approximately the same as two VX1000s. For a client who plans to reconfigure and expand the sand table over time, headroom is not a luxury — it's a requirement.

On the receiving side, MRV336 receiver cards (256×256 pixel capacity each) were distributed across the 1,050 COB Beta modules. Each receiver card drives two modules, with 37 active Ethernet ports each feeding 14–15 receiver cards — well within the recommended load per port. This conservative distribution means no single port is at risk of frame drops even under peak content load.

Three NovaStar MCTRL4K LED sending cards mounted side by side in 19-inch rack with sync card and Ethernet port connections visible
Technicians installing COB Beta P1.5 floor modules onto sand table base using magnetic direct mount during on-site construction in Shanghai
Technician mounting COB Beta P1.5 wall modules onto aluminum backing plate with magnetic strips during Shanghai showroom installation

By the Numbers

Project Specs

53.76
Square Meters
30.72 m² floor sand table + 23.04 m² LED wall across 9.6m width
24M
Total Pixels
Equivalent to 3 simultaneous 4K60 streams
MCTRL4K Processors
48 Ethernet ports (37 active + 11 spare) · Sync card for frame lock
1,050
COB Beta Modules
600 floor + 450 wall · Magnetic direct mount
5H
Surface Hardness
Epoxy encapsulation · Zero exposed SMD lamp beads
0
Modules Damaged
Through multiple assembly cycles · COB durability validated
How We Delivered

From Shenzhen to Shanghai in Three Weeks

Stage 01

Base Iron Layer Integration

Client's sand table base contractor embedded a thin iron absorption layer into the top surface during fabrication. DOIT VISION provided the magnetic mounting specifications and iron layer thickness requirements.

Stage 02

Production & Aging

1,050 COB Beta P1.5 modules manufactured in Shenzhen. Full burn-in aging test — each module passed zero dead pixel inspection before packaging into foam-lined transport cases.

Stage 03

Magnetic Installation

Modules placed directly onto the iron layer — no tools, no welding, no custom frames. 600 floor modules laid in under one day. 450 wall modules mounted to aluminum backing plate with magnetic strips.

Stage 04

MCTRL4K Sync & Calibration

Three MCTRL4K units configured with sync card for frame-level lock. 37 Ethernet ports mapped to 525 MRV336 receiver cards. Color calibration applied across the L-shaped canvas for seamless floor-to-wall transition.

COB Beta P1.5 modules undergoing factory burn-in aging test on racks at DOIT VISION Shenzhen facility with technician inspection

A real photo from the installation floor below — the display captured with a portion of modules lit during commissioning. The full synchronized effect is shown in the design render at the top of this page.

Worried about dead pixels after assembly?

COB epoxy eliminates the SMD fragility problem. Get a free LED protection comparison from our engineering team — COB vs SMD failure rates, real field data, and a rough cost comparison within 48 hours. No sales pitch, just numbers.

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Buyer's Questions

Frequently Asked Questions

Why choose COB instead of SMD for fine-pitch displays that get frequently assembled and disassembled?
SMD LED chips at P1.5 are approximately 0.5mm across and sit exposed on the PCB surface. During assembly, finger pressure, tool contact, and transport stacking can shear off multiple chips per module — each requiring desoldering and replacement. COB encapsulates all chips under a continuous 5H-hardness epoxy layer, turning the module into a solid-state optical panel. Force distributes across the epoxy plane rather than concentrating on individual chips. For installations undergoing multiple assembly cycles, COB eliminates the recurring dead-pixel maintenance cost that makes SMD uneconomical at scale.
Is P1.5 resolution enough — or should I pay more for P0.9?
P1.5 at a standing viewing distance of 1.2 meters or more exceeds the resolving power of the human eye — individual pixels are invisible. For a sand table that visitors view while standing, the typical eye-to-screen distance is 1.2–1.8 meters, well above the P1.5 retina threshold. P0.9 adds density that is mathematically invisible at this range but increases cost by approximately 40%. The exception is if visitors actively lean in to within 0.5 meters — in which case P0.9 becomes justified. For most showroom sand tables, P1.5 is the optimal price-performance point.
COB Beta vs COB Pro — which COB product line should I choose?
COB Beta is optimized for P1.2–P2.5 indoor fixed installations where cost-effectiveness matters as much as durability. It delivers the same epoxy encapsulation and 5H hardness as Pro, but at a pitch range suited for 1m+ viewing distances. COB Pro targets P0.6–P1.0 flagship scenarios — command centers, broadcast studios, luxury retail — where sub-1mm density justifies the premium. If your viewing distance is above 1 meter and you need impact resistance during assembly, Beta is the right choice. If you need retina-level density for close inspection, upgrade to Pro.
How many NovaStar processors do I need for a 54m² P1.5 LED wall?
54m² at P1.5mm generates approximately 24 million pixels. A single NovaStar MCTRL4K supports up to 8.84 million pixels across 16 Ethernet ports — so you need three units with a sync card. Each gigabit Ethernet port handles roughly 650,000 pixels, meaning you need approximately 37 active ports across the three processors. This project used 3×MCTRL4K (48 ports total, 11 spare) with an MRV336 receiver card driving every two COB Beta modules. The formula is: (your m² × 444,444) ÷ 8,840,000 = minimum MCTRL4K count, rounded up.
Can LED modules be mounted directly onto an existing base without building custom cabinets?
Yes, if the LED modules have integrated magnetic mounting points and the base surface is prepared with an iron absorption layer. COB Beta modules include strong magnetic attachment points rated to hold the module securely during normal use and transport vibration. The receiving surface — whether a sand table base, wall panel, or exhibition structure — must have a flat iron layer embedded. This eliminates the need for custom aluminum or steel cabinet frames, which typically add 4–6 weeks of design and tooling time plus significant material and labor cost.
Does magnetic mounting hold reliably for large installations like this?
Yes. The retention force of the magnetic mounting points on COB Beta modules exceeds the forces generated by normal exhibition use, accidental bumps, and transport vibration. Each module has multiple magnetic points distributed across its surface area, creating a stable mechanical bond to the iron layer. The Shanghai sand table installation used this method for 600 floor modules and 450 wall modules — none have shifted or detached during operation, reconfiguration, or transport between exhibition cycles.
What is the typical lead time for a COB sand table project of this scale?
COB Beta P1.5 modules are standard production items — no custom PCB design or mold tooling is required. For a 54m² project with 1,050 modules, typical lead time is 2–3 weeks for production and factory burn-in aging, plus transport time to your location. Magnetic mounting significantly accelerates on-site installation — this project's 1,050 modules were laid in under two days, compared to 5–7 days for a traditional cabinet-and-frame approach. The total timeline from order to operational display is typically 3–5 weeks depending on destination and customs clearance.

Your Custom Shape, Engineered

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Manufacturer
DOIT VISION
Author
Kris Liang, Co-Founder & Lead Engineer
Author Experience
19 years LED display engineering
Author LinkedIn
https://www.linkedin.com/in/krisliang/
Content Type
Case Study
Primary Topic
COB Beta P1.5 Sand Table Display & L-Shaped LED Wall — Shanghai, China
Key Technologies
COB Beta P1.5, 5H Epoxy Encapsulation, Magnetic Module Mounting, NovaStar MCTRL4K, MRV336 Receiver Card
Project Scope
53.76 square meters (30.72m² floor + 23.04m² wall)
Pixel Pitch
P1.5
LED Technology
COB (Chip-on-Board)
Client Location
Shanghai, China
Protection Strategy
COB epoxy encapsulation — zero exposed SMD lamp beads for impact resistance during assembly and exhibition
Structure
Magnetic direct mount — zero custom cabinets, zero welding
Video Processor
3 × NovaStar MCTRL4K with sync card, 37 active Ethernet ports
Date Reviewed
August 2026
Certifications
CE, FCC, RoHS, CB, ISO 9001, UL/ETL (COB Pro series)
Countries Served
55+
Founded
2013, Shenzhen, China
In-House Engineers
15
Control Systems
NovaStar, Brompton Tessera, Colorlight, Linsn
Get in touch
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Manufacturer
DOIT VISION
Founded
2013, Shenzhen, China
Headquarters
Shenzhen, Guangdong, China
Certifications
CE, FCC, RoHS, CB, ISO 9001
Official Website
https://www.doitvision.com/