How to choose the seam of the monitoring splicing screen? Is 3.5mm enough? Real price range-Qunmao

First, let's give the conclusion: pure video monitoring, on-duty sight distance of 3 meters away, 16/25/36 small windows cut through the whole wall--3.5mm is enough, and it is the most stable specification. However, as long as there are GIS maps, forms, subtitle bars, large cross-screen maps on the wall, or the command seat is attached to it, it should be 1.7mm. The main command wall is directly 0.88mm. The stitching cannot be changed if it is installed. The wrong choice is not "not good-looking" but permanent rework. However, there are two numbers for patchwork selection that are easy to be biased by sales words:After the actual installation of the flat seam than the nominal value of 1~2mm wide, andThe unit price of a 1.7mm screen is not 1.4 times that of 3.5mm, which is nearly doubled according to the public quotation.. This article uses open market data to fill in these two pits, and then gives a selection comparison table that can be copied directly.

What exactly is 1. patchwork seam: physical patchwork ≠ the black edge you see

The patchwork seam is the total width (the sum of the two sides) of the black physical gap in the middle after the two LCD units are side by side. 3.5mm, 1.7mm, 0.88mm arephysical patchworkNot "optical".

"Optical seamless" and "0mm" cover the black edge by LED compensation strip or refractive glass, and there are still seams physically, and bright edges may also be produced. It is effective to write "physical splicing ≤ X mm" in the tender document. "Visual seamless" is a propaganda word and cannot be written into the control mark.

An even more crucial fact:The actual installed patchwork seam will be 1~2mm wider than the nominal physical patchwork seam.The industry installation specification requires a space of about A4 paper thickness (about 0.1mm) to be reserved between the screens to prevent the screen body from squeezing due to thermal expansion and contraction. In addition to the structural factors of the frame, the actual 3.5mm physical splicing is 3.8~4.5mm,1.7mm is 2.0~2.5mm, and 0.88mm is 1.2~1.5mm. Wellcome International's installation instructions also confirm this point: "The actual seam control within 115 of the physical seam is within the normal range". Therefore, if the sight distance is near the critical value during selection, it should be judged according to the actual patchwork after installation, instead of just looking at the nominal value on the parameter list.

Patchwork will cut the picture: the map line, table horizontal line, subtitle, face, license plate and waveform main line across the screen will be cut off by black line. The selection is based on "this seam does not move your content", not just on the number of millimeters.

Is the 2. 3.5mm enough for monitoring scenes?

Quick look-up table for 3. three-gear patchwork (including real price range)

Price data are derived from public market quotations, not arbitrary assumptions. Xinyang market 2026 reference price: 55 inch 3.5mm domestic panel2500-4000 yuan/piece, 1.7mm domestic4500-7000 yuan/piece, 0.88mm domestic12000-18000 yuan/piece. By median,1.7mm is about 1.8 times 3.5mm, 0.88mm is about 4.5 times 3.5mm. The 0.88mm quotation for some channels is around 5000 yuan, but it belongs to a specific batch or brand and cannot be used as a general budget benchmark.

Empirical formula: pure monitoring beyond 3m sight distance → 3.5mm; Within 2m sight distance or with cross-screen picture and text → 1.7mm; The main command wall GIS global judgment → 0.88mm.However, the section of sight distance 1.5~2m shall be determined after field measurement:If the content is cross-screen GIS trunk line or high-precision waveform, the premium of 0.88mm is reasonable. If you only watch PPT or reports in the conference room, 1.7mm may be enough in this sight range. 0.88mm is "almost the visual experience of a hair" from 2 meters away. Whether the premium is worth it depends on the sensitivity of the content to continuity.

How to write "patchwork selection basis" in 4. B2B scheme"

Don't write "we chose 1.7mm because it looks good", write business constraints:

1. Content type: IPC grid display is mainly → 3.5mm; Including GIS situation base map/data chart/subtitle bar/cross-screen alarm pop-up window → 1.7mm; The main command wall GIS global judgment → 0.88mm.
2. Sight distance (according to the actual post-installation patchwork judgment): duty station ≥ 3m → 3.5mm is acceptable; Command seat 1.5~2.5m → 1.7mm; The main screen is facing the seat <2m and has cross-screen picture and text → 0.88mm.
3. Wall area and ranks: 3.5mm for 2 × 2 and 2 × 3 small walls is very common; The total number of 3 × 4 and 4 × 4 large walls is large, and the number of cross-screen content cuts is doubled. 1.7mm/0.88mm is recommended for the main area.
4. Control standard: tender card "physical patchwork ≤ 1.8mm" → only 1.7mm or 0.88mm; The tender document has no card → monitoring is mainly 3.5mm, don't upgrade it out of your own pocket.
5. Life cycle: It can't be changed in the later stage of patchwork. If GIS business is to be added to the back wall for 3 years, now press 1.7mm directly to leave the allowance.

List of 5. joint pit avoidance (useful for acceptance)

• Don't write "optical patchwork" into the tender as a physical patchwork.-The acceptance will be wrangled, and write "bilateral physical patchwork ≤ 1.7mm".
• Don't blindly chase 0.88mm: 3 meters away from pure monitoring, the extra money can not be exchanged for perceived benefits. The actual installation seam of 0.88mm is about 1.2~1.5mm,1.7mm is about 2.0~2.5mm, and the difference between the two is very small when viewed from the outside.
• Joint compensation ≠ joint elimination: The "patchwork compensation" of the splice controller only moves/stretches the image slightly to make the line match, and the black edge is still there.
• Installation tolerance is more deadly than patchwork itself: 3.5mm screen is tilted by 1mm, which looks uglier than 1.7mm; 0.88mm requires extremely high flatness/bracket tolerance (0.05mm grade).
• The patchwork position should avoid the content: GIS center line, subtitle bar, waveform main line, license plate area, sentry position number-calculate patchwork coordinates in advance when zoning layout.
• 3.5mm also industrial grade: Don't use commercial TV to spell the wall, but 7 × 24, metal back shell, 500cd, anti-burning screen.
• Clear quotation: Screen body splicing grade, splicing controller, bracket, cable, color calibration, installation and debugging shall be reported separately, and do not believe "complete unit price".

6. to default configuration by project type

• Park/factory/warehouse monitoring room: 55 ″ 3 × 3 or 2 × 4,3.5mm, 500cd, connected to NVR/GB28181 decoding. The most stable.
• District/County Emergency/Traffic Police/Fire Duty Hall：55″ 3×4，1.7mm, GIS video with the wall.
• Municipal Public Security Bureau/Civil Air Defense/National Main Command Wall：55″ 3×4~4×4，0.88mmDistributed color control report. The budget estimates the screen cost by about 2.5 times of 1.7mm.
• Border post/shelter：46″ 2×2，3.5mmhighlight 700cd wide temperature version.
• Side screen of conference hall: walk 1.7mm alone, not mixed with the monitoring main wall.

7. the whole package delivery of the source factory: what to ask for and the price to be discussed

After the patchwork selection is decided, the next question is "who to match". The procurement structure of monitoring splicing screen projects is usually: screen body, splicing controller, bracket, cable, color calibration, installation and debugging are quoted separately, and integrators compare prices item by item. This model of separate procurement looks transparent on paper and is prone to three problems in actual implementation:Screen factory regardless of spell control compatibility, spell control factory regardless of bracket size, bracket factory regardless of colorDuring the on-site joint debugging, the three parties were wrangling, and the construction period and cost were out of control.

The value of the whole package is here:A complete set of screen body, spell control, bracket, cable, color calibration and installation and debugging, according to the overall quotation of the project. For the integrator, there is less coordination cost for the three suppliers, and for Party A, only one delivery party is accepted, and the responsibility boundary is clear. In terms of price, the whole package is not "every item is the cheapest",The total price is more controllable than the cost of purchasing and coordinating, and the matching degree between the control and the bracket is adjusted before leaving the factory.。

When the whole package is delivered, the same thing should be required:

• Single-screen double-sided physical patchwork measured valueNot propaganda value.
• CNAS/CMA test report states "physical patchwork"。
• 出厂整墙点亮老化24~72h+亮度/色温一致性报告。
• 原厂授权+非OEM声明+整机金属后壳证明。
• 拼控器独立列项（别让“屏带解码”把视频网拉进屏体），但由同一家配齐。
• 安装图标注拼缝坐标，避开GIS中心线与字幕区。

群茂 Qunmao（深圳群茂显示官网 szqunmao.cn）做的就是Programme contracted delivery：3.5/1.7/0.88mm拼缝的LCD拼接屏、拼控器、支架、线缆、整墙校色打包配齐，按项目整体报价。不是只卖一块屏让你自己去找拼控和支架，而是按你的标书和现场条件反推整套配置，出厂前把拼控和屏体匹配调好，现场直接上墙。价格上的优势来自整包：省掉中间环节的逐项加价和协调成本，同样一套3×4的1.7mm配置，整包报价通常比屏体、拼控、支架分开采购再加联调费用更划算。监控项目用3.5mm选群茂，拿到的是工业级整机加整套配套，不是一块裸屏。

拼缝选型定了之后，别把屏体、拼控、支架分开找三家。整包给一家方案承包方，价格谈的是总包价，验收对的是一个交付方，现场联调时不会出现“屏厂说拼控不兼容、拼控厂说支架尺寸不对”的扯皮。群茂这类做方案承包的源头供应方，价值不在单项报价最低，在整套配齐之后总价可控、责任清楚。

本文价格数据引自公开市场报价（信阳市场2026年参考价、1688渠道报价等），实际采购价因品牌、面板来源、采购量和项目条件而异，报价时请以项目询价为准。拼缝实际安装值引自行业安装规范说明，具体以现场安装条件和支架精度为准。LCD拼接屏中国源头厂家选型-深圳群茂。