What Is a Visual Inspection?
A visual inspection is an examination method in which a human examiner uses simple tools like magnifying glasses to inspect and confirm the absence of quality issues. This analog method relies on the experience and skills of the inspector and is widely used across various industries to ensure product and service quality within workflows.
In the semiconductor industry, inspectors use focused lamps in darkrooms within clean rooms to identify defects and foreign particles in LSIs, wafers, and photomasks. Similarly, aircraft pilots perform visual checks around their aircraft after maintenance, ensuring safety before flights. Despite being one of the oldest inspection methods, visual inspection remains crucial for quality maintenance.
Uses of Visual Inspections
Visual inspections in manufacturing are conducted at critical stages: incoming inspection of materials, inter-process inspections, and pre-shipment inspections. Incoming inspection, often the first step in the process, involves verifying materials against attached documents. Inter-process inspections, crucial for detecting issues before proceeding to the next stage, are frequently carried out visually, although machine-based inspections are also common. Pre-shipment inspections, conducted just before dispatch, are essential to avoid shipping products with visible defects, thereby safeguarding the company’s reputation.
Principles of Visual Inspections
The importance of visual inspections persists even with advancements in inspection technology. They allow for flexible problem detection beyond predefined inspection items. In contrast, inspection devices, limited by their design, may miss unexpected issues or problems outside their inspection range. B2B businesses frequently conduct quality audits, where visual inspections at manufacturing stages can enhance trust in quality management. Despite advancements in diagnostic technologies and AI, visual inspection remains unparalleled for identifying unforeseen issues.
Types of Visual Inspections
Diverse industries incorporate daily visual inspections:
- In the semiconductor industry, shipment approval inspections involve visual checks by the purchaser’s employees to confirm the final condition of high-value equipment.
- Construction sites use visual inspections at each stage, such as before pouring concrete, to ensure correct reinforcement usage, and post-construction checks for leaks and cracks.
- Automotive maintenance and rental car companies conduct visual inspections of vehicles during acceptance and return, often with the customer present, to prevent disputes during handovers.