How are the grades of LCD screen panels determined in the market?
News 2026-01-16
In the industrial sector, the quality and reliability of LCD panels are paramount. Unlike consumer-grade displays, industrial LCD panels require stable operation over extended periods in complex environments, thus necessitating more stringent and complex grading standards. Understanding these standards can help industrial equipment manufacturers and purchasers better select LCD panels that meet their specific needs.
LCD Panel Grade Evaluation Standards
Industrial LCD panels are typically classified into three grades based on quality: Grade A, Grade B, and Grade C.
Grade A (A-Grade or A+)
Definition: The highest grade of screen, with the most stable quality and fewest defects.
Specifications: Almost no defects in appearance, display effect, and function. Typically requires no bright spots, no dark spots, no color difference, no scratches, and no water ripples. These screens undergo multiple rigorous tests at the factory to ensure their optical and electrical performance meets the highest standards.
Applicable Scenarios: Fields with extremely high display quality requirements, such as medical imaging, aerospace, and broadcast-grade monitors.
Grade B (B-Grade or B)
Definition: Quality is lower than Grade A screens, and may have a few acceptable defects.
Specifications: May have 1-3 bright or dark spots in appearance or display, but these defects do not affect normal use and must be within the limits allowed by industry standards. In addition, the color difference, brightness, and contrast ratio of Grade B screens may fluctuate slightly.
Suitable Scenarios: Most industrial control and automation equipment, digital signage, etc., meeting the needs of general industrial applications.
C-Grade Screens (or C-level)
Definition: Lower quality than B-grade screens, with more defects.
Specifications: May have more bright spots, dark spots, scratches, and even minor functional defects. These screens are usually defective products from the production process and are not recommended for devices with high display requirements.
Suitable Scenarios: A very small number of simple display devices with very low display requirements and cost as a priority.
Classification by Environmental Adaptability
The operating temperature range of industrial LCD screens is a key indicator of their “industrial grade” rating:
| Grade/Classification | Operating Temperature Range | Typical Application Scenarios |
| Commercial Grade | 0°C～50°C | Offices, retail outlets, general indoor equipment |
| Light Industrial/Semi-Industrial Grade | 0°C～60°C or 0°C～70°C | Temperature-controlled workshops, indoor automation equipment, kiosks |
| Standard Industrial Grade | −20°C～60°C | Most factory environments, cold storage, standard outdoor cabinets |
| Wide Temperature Industrial/Military Grade | −30°C～80°C | Or wider, suitable for extreme environments such as frigid regions, high-temperature furnace control, transportation (ships, railways), and special vehicles |
Industrial displays are classified by protection level
Industrial displays must be able to withstand water, dust, impact, and vibration, quantified using internationally recognized IP and IK ratings:
IP Protection Rating
First digit (dustproof): 0–6 (6 is the highest rating, completely preventing dust ingress).
Second digit (waterproof): 0–8 (8 is the highest rating, allowing prolonged immersion in water).
Typical industrial applications: IP65 (dustproof, withstands low-pressure water jets) or IP67 (dustproof, withstands short-term immersion in water) are common standards for industrial displays.
IK Shock Resistance Rating
Measures the equipment enclosure’s ability to protect against external mechanical impacts, measured in Joules.
IK01 to IK10: The higher the number, the stronger the shock resistance. For example, IK10 indicates it can withstand 20 Joules of impact energy.
Classification by Display Performance
Industrial environments present complex lighting conditions with specific requirements for display performance:
Brightness (Luminance)
Consumer-grade displays typically have a brightness of 250–350 cd/m². Industrial-grade displays often require higher brightness; products with a brightness greater than 500 cd/m² are considered high-brightness screens, while those greater than 1000 cd/m² are designated as “Sunlight Readable” and are suitable for outdoor equipment.
Backlight Lifetime (MTBF)
Industrial equipment typically needs to operate 24/7. Therefore, the mean time between failures (MTBF) for backlights is usually required to be above 50,000 hours, while consumer products may only have 20,000–30,000 hours.
By Reliability and Certification Classification
Some high-risk or critical industries require displays to pass specific reliability tests or standard certifications:
| Sub-specification for LCD Displays | Applicable Scenarios | Key Test Contents |
| MIL-STD-810G/F | Military, Aviation, Harsh Outdoor Applications | US Military Standard, testing comprehensive robustness including shock resistance, impact resistance, moisture resistance, and high/low temperature resistance |
| ATEX/IECEx | Explosion Hazard Areas (e.g., petrochemical, mining) | Explosion-proof safety standards for equipment used in environments with explosive gases or dust |
| National Standard GB/T 18910 | Sub-specification for LCD Displays | Provides quality assessment procedures, inspection requirements, sampling requirements, tests, and methods for evaluating LCD displays (primarily for passive monochrome screens) |
By Quality Control and Supply Chain Classification
For industrial customers, supply chain stability and stringent quality control are also crucial components of “industrial grade”:
Long-Term Supply
Industrial projects have long lifecycles (5-10 years), therefore industrial-grade panel suppliers commit to longer supply cycles, typically over 5 years, to ensure customers don’t need frequent system design changes.
Strict Defect Tolerance
Industrial-grade panels typically have stricter tolerances for dead and bright pixels than consumer-grade panels to ensure that critical HMI information display is not interfered with.
Frequently Asked Questions(FAQ)
What are the main differences between Grade A and Grade B LCD screens?
Grade A screens have virtually no defects in appearance, display effect, and functionality, making them suitable for applications with extremely high display quality requirements. Grade B screens may have a few acceptable defects, such as 1-3 bright or dark spots, but these do not affect normal use and are suitable for general industrial applications.
Are the brightness requirements for industrial LCD screens higher than those for consumer-grade screens?
Yes, industrial displays typically require higher brightness, especially for outdoor equipment. Products with a brightness greater than 500 cd/m² are considered high-brightness screens, while those greater than 1000 cd/m² are referred to as “sunlight-readable.”
How to determine if the LCD screen’s supply cycle meets the needs of an industrial project?
Industrial projects typically have a lifespan of 5-10 years. Therefore, industrial panel suppliers should commit to a supply cycle of at least 5 years to ensure that customers do not need to frequently change system designs.
Are Grade C screens suitable for all industrial applications?
C-grade screens have many defects and are generally not recommended for devices with high display requirements. They are only suitable for a very small number of simple display devices with very low display requirements and cost as the primary consideration.
What are the common standards for the protection rating of industrial LCD screens?
Common protection ratings for industrial displays include IP65 (dustproof, withstands low-pressure water jets) and IP67 (dustproof, withstands short-term immersion in water). In addition, an impact resistance rating of IK10 indicates that it can withstand an impact energy of 20 joules.
Conclusion
Determining the grade of industrial LCD panels is a multi-dimensional and comprehensive evaluation process, involving multiple aspects such as quality, environmental adaptability, protection level, display performance, reliability and certification, as well as quality control and supply. When purchasing, it is necessary to select the most suitable “industrial-grade” product based on the severity of the application environment and the required certification level. Understanding these standards can help industrial equipment manufacturers and purchasers better select LCD panels that meet their needs, ensuring stable operation of equipment in complex environments.
