1. Project Overview

This customized high-precision post-printing machine vision inspection system is developed for finished pharmaceutical packaging printing products, including pharmaceutical hang tags, pharmaceutical labels and other finished materials. Supported by real-time image capture via high-speed industrial cameras, the system intelligently inspects various quality defects of pharmaceutical packages, such as printing defects, barcode grades, variable supervision data, surface stains, missing prints, die-cut misalignment, gold and silver hot stamping flaws, mixed and wrong serial numbers. It realizes automatic identification, judgment and rejection of pharmaceutical packages with wrong labels, missing information, flaws and defective products, controls the production quality of pharmaceutical packaging, and meets quality inspection requirements for mass production of various pharmaceutical labels and hang tags.

2. Inspection Requirements and Performance Indicators

In view of the high standards and compliance requirements of pharmaceutical packaging production, the core inspection indicators of the system are designed as follows to realize full-dimensional quality inspection of finished pharmaceutical packages and comply with pharmaceutical packaging inspection specifications:

Inspection Mode: Offline inspection after printing

Applicable Materials: Coated art paper, white cardboard, grey cardboard, gold and silver cardboard

Inspection Width: 300~350 mm

Operating Speed: Stable continuous inspection with a maximum inspection speed of 120 m/min, matching the mass production rhythm of pharmaceutical packages

Inspection Precision:

① Minimum detectable area of appearance defects such as missing prints, ink spots and stains: Front side ≥0.2 mm²;

② Overprint deviation inspection precision: ≥0.2 mm to avoid misregistration and ghosting of graphics and texts on pharmaceutical packages;

③ Die-cut deviation inspection precision: ≥0.2 mm to ensure regular dimensions without cutting offset or damage;

④ Scratch defect inspection: Accurately detect vertical and horizontal scratches, ink lines and streaks with vertical width over 0.2 mm, horizontal width over 0.15 mm, length over 15 mm and contrast above Grade 20;

⑤ Partial color difference inspection: Color difference value ΔE≥2.5 ΔELab to accurately identify color deviation and uneven color of pharmaceutical packages and guarantee consistent and compliant appearance of pharmaceutical packaging.

3. Full-Dimensional Core Inspection Functions

3.1 Printing and Appearance Defect Inspection (Conventional Defect Inspection)

Taking standard pharmaceutical package templates as benchmarks, the system compares captured images in real time to identify physical surface flaws and printing failures of pharmaceutical packages, covering common quality defects:

Printed Text & Pattern Defects: Detect missing prints, blocked plates, dirt spots, ink specks, streaks, ink splashes, knife lines, incomplete strokes and broken graphics on pharmaceutical packages, effectively preventing abnormal printing of drug instructions, logos and patterns.

Color Quality Control: Support quantitative monitoring of overall and local color difference of pharmaceutical packages, real-time detection of printing color deviation, uneven shade, local fading and discoloration to ensure consistent and compliant color of products in the same batch.

Post-Forming Defects: Inspect forming flaws including die-cut misalignment, edge glue overflow, missing labels, broken production strips, corner damage and warped edges.

Special Process Defects: For special processes such as gold stamping, silver stamping, film lamination and varnish coating of pharmaceutical packages, detect offset, missing, incomplete and peeling hot stamping, uneven varnish coating, surface scratches, blisters and wrinkles on laminated films.

3.2 Variable Data and Barcode Compliance Inspection (Special Inspection for Pharmaceutical Traceability)

In response to pharmaceutical industry requirements of drug supervision traceability, one item one code and batch control, the system conducts high-precision compliance comparison on variable information and traceability barcodes of pharmaceutical packages to eliminate information errors and substandard grades.

First-level quality grading for barcodes & QR codes: Real-time reading of 1D barcodes, traceability QR codes and drug supervision codes on pharmaceutical packages, online inspection of core indicators including barcode contrast, modulation ratio, decoding rate and defect degree to reject unqualified products and guarantee readable and traceable drug supervision codes during scanning.

3.3 Text Compliance Inspection and Error Code Prevention Control

The system intelligently identifies and compares core compliance texts on pharmaceutical packages, including production date, batch number, expiry date, product serial number, specification model, manufacturer information and implementation standards. It verifies text integrity, clarity and readability to avoid incomplete characters, broken lines, wrong prints and missing prints.

Duplicate, Missing and Skipped Code Control: Linked with exclusive pharmaceutical package code packages and code pool databases, the system dynamically compares variable codes in real time to identify severe quality problems such as duplicate codes, missing codes, skipped numbers, wrong codes and mixed batch codes, satisfying pharmaceutical traceability management requirements of one item one code.

4. Hardware System Architecture

A highly compatible hardware configuration is adopted to adapt to material characteristics of laminated, high-gloss, high-reflective and color-printed pharmaceutical packages as well as high-speed mass production inspection scenarios, solving troubles such as reflection interference, color deviation and blurry high-speed imaging. Hardware configurations can be customized and optimized according to customer pharmaceutical package categories and production demands. The basic hardware architecture is as follows:

4.1 Industrial Cameras

① Line Scan Camera: Suitable for high-speed wide-width continuous production lines of pharmaceutical packages, realizing blind-spot-free and omission-free inspection under high-speed operation via continuous scanning imaging.

② Area Scan Camera: Suitable for imaging inspection of finished single pharmaceutical packages and low-speed fixed inspection stations. Matching of Color & Monochrome Cameras: High-definition color cameras are standard for inspection involving color graphics, color difference and color processes of pharmaceutical packages; high-definition monochrome cameras are adopted for scenarios only requiring structural flaw detection and barcode reading to improve imaging resolution and inspection precision.

4.2 Light Source System

Light sources are configured to meet imaging demands of various pharmaceutical package materials. Dome shadowless light sources are used for high-reflective pharmaceutical packages with lamination and hot stamping to eliminate interference from surface reflection, light spots and shadows. Strip lights and ring lights are equipped for ordinary paper pharmaceutical packages to deliver clear images with prominent defect features and provide high-quality image support for inspection.

4.3 Image Capture Card and Processing Host

Equipped with high-speed image capture cards and industrial-grade processing hosts, the system ensures real-time image data collection, high-speed transmission and millisecond-level arithmetic processing during high-speed pharmaceutical package production, effectively solving data delay and stuttering problems and guaranteeing real-time performance and stability of inspection.

5. Closed-Loop Control and Defective Product Disposal Mechanism

Accurate detection and effective interception are the core of pharmaceutical package quality inspection. For cut single pharmaceutical labels and hang tags, the system immediately links pneumatic blow-off valves and mechanical push rods of the equipment to perform high-speed effective rejection once defective products are identified. Defective labels are automatically sorted into exclusive waste areas to realize full-automatic closed-loop of "Inspection - Judgment - Rejection - Isolation" and effectively prevent defective products from flowing into subsequent processes.

6. Data Management and Upstream Process Tracing

The system supports pharmaceutical package inspection data statistics and process tracing. It automatically performs intelligent classification and summary statistics on various defects, calculates the proportion of dirt spots, knife lines, color differences, unqualified barcodes, wrong/missing codes and die-cut misalignment, and automatically generates data pie charts and defect trend analysis graphs. All inspection data and defect records are automatically archived, associable with upstream production processes including printing, film lamination, die-cutting and hot stamping to realize problem tracing, process optimization and quality review, assisting pharmaceutical enterprises in standardized and normalized quality control.