Working Principle of Optical Sorter

Operational Mechanism of Optical Sorter

Optical sorters, with optical inspection at their core, achieve automated material sorting through a four-step process: conveying – inspection – analysis – sorting.

The detailed principles are as follows:

First, materials are transported to the inspection area at a constant speed via a vibrating feeder or conveyor belt, ensuring even distribution and no accumulation, laying the foundation for accurate inspection. Subsequently, a high-stability light source (such as an LED or laser) illuminates the material, fully revealing its surface or internal optical properties (color, shape, transmittance, and spectral information).

Next, a high-resolution optical sensor （such as a CCD camera or spectrometer) captures the material’s optical signals in real time, converting them into electrical signals for transmission to a high-speed image processing unit. This unit analyzes and compares the signals within milliseconds based on pre-set sorting criteria (such as color thresholds for qualified materials and defect characteristics), rapidly identifying qualified and unqualified products (or target materials and impurities).

Finally, the image processing unit sends instructions to the actuators (such as air jet valves and push rods). When the materials to be sorted reach the specified position, the actuators move precisely. Light materials are often separated by instantaneous air jets using air jet valves, while heavy materials are pushed through using push rods. Ultimately, different types of materials are efficiently diverted and the entire sorting process is completed.

Applications of Optical Sorter

Optical sorting machines rely on optical technology for automated sorting, with efficient sorting and a processing capacity far exceeding that of manual labor. They have high precision and can accurately identify subtle differences in materials. They are highly adaptable and can match materials of different shapes and types and complex production environments. They have good stability, reduce human errors, and can also lower manpower and operation and maintenance costs, contributing to intelligent production.

Common applications include:

• Plastic Recycling: Sorting different types of plastics, such as PET, HDPE, and PVC, for more effective recycling.
• Municipal Solid Waste (MSW): Separating recyclables from mixed waste streams to enhance recycling rates.
• Metal Recycling: Identifying and sorting ferrous and non-ferrous metals for recycling.
• Paper and Cardboard: Sorting different grades of paper and cardboard to improve recycling quality.
• Glass Recycling: Separating glass by color and type for better recycling outcomes.

Benefits of Using Optical Sorter

Implementing optical sorter in material separation processes offers numerous benefits:

• Increased Efficiency: Enhances the speed and accuracy of waste sorting, reducing manual sorting requirements.
• Improved Material Recovery: Increases the recovery rate of valuable materials, supporting recycling efforts.
• Cost Savings: Reduces labor costs and operational expenses through automated and efficient sorting.
• Enhanced Product Quality: Produces cleaner, higher-quality separated materials, improving the value of recycled products.
• Environmental Impact: Supports sustainable waste management practices by increasing recycling rates and reducing landfill usage.

Parameters of Optical Sorter