When purchasing smartphones or tablets, screen quality remains a primary concern for consumers. This detailed standard operating procedure provides clear guidelines for evaluating screen conditions, helping buyers make informed decisions.
I. Preparation: Setting Realistic Expectations
Before inspection, determine your acceptable tolerance levels. Are you seeking absolute perfection, or can you accommodate minor imperfections? Establishing these parameters will facilitate more accurate assessments.
II. Inspection Methodology: Critical Factors
- Lighting conditions: Conduct examinations under ample illumination from multiple angles to reveal subtle scratches.
- Perimeter examination: Pay particular attention to screen edges where chips or cracks often originate.
III. Screen Condition Classification System
The following standardized grading system applies to smartphones, tablets, and foldable devices:
1. Pristine Condition
Definition: Virtually flawless, permitting only microscopic scratches.
Smartphones/Tablets: Scratches under 3mm (5mm for tablets), maximum five occurrences, imperceptible to touch; no cracks, chips, or earpiece mesh damage.
Foldables: Same parameters as smartphones regarding scratches.
2. Minor Surface Scratches
Definition: Superficial markings without functional impact.
Smartphones: Scratches under 10mm; either 3-10mm (≤5) or sub-3mm (>5), all touch-imperceptible.
Tablets: Scratches under 20mm; either sub-5mm (>5) or 5-20mm (≤5), touch-imperceptible.
3. Visible Scratches
Definition: Noticeable markings potentially affecting user experience.
Smartphones: Scratches ≥10mm or sub-10mm hard scratches; alternative combinations meeting specified length/quantity thresholds.
Tablets: Scratches ≥20mm; various combinations meeting length/quantity parameters.
4. Minor Hard Scratches
Definition: Tactile imperfections detectable by touch.
Smartphones: Hard scratches 10-20mm; or sub-10mm (5-10) or 10-20mm (≤5), all touch-detectable.
Tablets: Hard scratches under 20mm; either 5-20mm (≤5) or sub-5mm (>5), touch-detectable.
5. Significant Hard Scratches
Definition: Extensive tactile imperfections affecting aesthetics.
Smartphones: Hard scratches >20mm; or 10-20mm (5-10) or >20mm (<5), all touch-detectable.
Tablets: Hard scratches ≥20mm; either 5-20mm (>5) or ≥20mm (≥1).
6. Severe Hard Scratches
Definition: Dense network of tactile imperfections substantially impairing usability.
Smartphones: Multiple configurations meeting stringent length/quantity thresholds, all touch-detectable.
7. Minor Edge Damage (≤1.5mm)
Definition: Slight perimeter chips, cracks, or fractures.
Standard: Damage under 0.5mm considered intact; 0.5-1.5mm classified here.
8. Significant Edge Damage (>1.5mm)
Definition: Pronounced perimeter damage.
9. Foldable Display Standards
Specialized criteria address unique foldable device considerations:
- Pristine: Sub-3mm (≤5) touch-imperceptible scratches
- Minor Wear: Various combinations of touch-detectable scratches, protective film issues, or indentations
- Moderate Wear: More extensive versions of above criteria
- Severe Creasing: Visible folding marks without structural failure
- Structural Failure: Cracks or separation along fold lines
IV. Special Considerations
- Protective film imperfections equate to screen defects
- Secondary display evaluation varies by device type
V. Measurement Protocols
Scratches: Maximum linear distance between endpoints
Cracks: Larger dimension (length/width) determines classification