How to choose oil-free lubricated air compressor for precision optical coating
Precision optical coating background
Precision optical coating is the core technology of high-end optical devices, involving the deposition process of nanoscale coatings such as anti-reflection films and filter films. According to compressed air purity rating standards ISO 8573-1:2010The oil content of compressed air must be less than 0.001mg/m³, the dust content must be ≤0.01μm, and the dew point temperature must be stable at-70℃ (PDP). If the compressed air contains oil or particulate matter exceeds the standard, it may cause pinholes on the surface of the film, uneven refractive index, and even cause batch optical performance failure.Oil-free lubricated air compressorThrough fully enclosed oil-free technology, it has become necessary equipment to pass the German Tüv “0” oil-free certification.
Why does precision optical coating require oilless lubricated air compressors?
- Optical performance guarantee: Oil contamination will cause the light transmittance of the film to decrease by 0.5%-1.2%(exceeding the ISO 9211-4 optical film standard tolerance).
- process stability: Vacuum coating chamber requires air pressure fluctuation ≤±0.2%(required to support quality management system certification).
- Cleanliness compliance: SEMI S2/S8 standard stipulates that the dust content of compressed air in clean rooms shall be ≤Class 1.
- device compatibility: The magnetron sputtering process requires dew point temperature ≤-60℃ (verification by environmental management system certification certificate is required).
For example, Shanghai Granklin Group’s oil-free lubricated air compressors adopt oil-free compression technology that meets international standards, and have passed the certification of no pollution and no heavy metal content in the system, and support operation in Class 10 clean workshops.
Selection of core parameters for precision optical coating
according toISO 8573-1:2010 Class 0withSEMI F47Standard, the following parameters need to be verified:
- oil content:<0.001mg/m³ (German Tüv “0” oil-free certification is required).
- dew point control:-70℃ (PDP) ±1℃ (Occupational Health and Safety Management System Certification Required).
- pressure stability: ±0.2%(product quality and safety certification certificate verification is required).
- vibration level: ≤1.8mm/s (complies with ISO 10816-3 mechanical vibration standard).
Oil-free lubricated air compressors use multi-stage filtration and intelligent temperature control systems, combined with EU CE certification to ensure the stability of the air source during the vacuum coating process.
Potential risks of not using oil-free air compressors
If traditional oil lubrication equipment is used, it may cause:
- yield loss: The condensation of oil mist causes the adhesion of the film to decrease, and the batch scrapping rate increases by 8%-15%.
- equipment pollution: Oil is carbonized and deposited on the inner wall of the vacuum pump, increasing maintenance costs by 200%.
- Certification fails: IEC 61215 photovoltaic module certification was revoked due to substandard optical performance.
- legal disputes: AR/VR lens manufacturers face consumer class action lawsuits over glare issues.
by comparingISO 8573-1:2010Standard and traditional equipment parameters (oil content ≥0.01mg/m³) can clarify the necessity of oilless lubrication technology.
Economic benefits of using oil-free air compressors
- Reduce coating costs: Clean gas sources increase target utilization by 12%-18%, saving annual material costs by more than 500,000 yuan.
- extend equipment life: The oil-free design extends the vacuum pump maintenance cycle from 3 months to 24 months.
- energy consumption optimization: The isentropic efficiency has been increased to 92%, and the annual electricity bill has been saved by more than 250,000 yuan (150kW model).
- market competitiveness: Comply with JEDEC JESD625 optical device reliability standard, customer orders increased by 30%.
Comparison of oil-free air compressor versus traditional equipment in precision optical coating
| parameters | Oil-free lubricated air compressor | Traditional oil lubrication equipment |
|---|---|---|
| oil content | <0.001mg/m³ (Tüv certification) | ≥0.1mg/m³ (three-level filtration required) |
| Dew point control accuracy | ±1℃ (intelligent temperature control) | ±5℃ (mechanical adjustment) |
| pressure fluctuations | ±0.2%(PID closed loop control) | ±1.5%(mechanical valve adjustment error) |
| Average annual maintenance cost | 50,000 – 80,000 yuan (oil-free design) | 200,000 – 300,000 yuan (oil-containing filter replacement) |
| equipment life | 15-20 Year (fully enclosed structure) | 5-8 Year (caused by oil pollution corrosion) |
| compliance of | Passed 7 certifications including CE/SEMI/Tüv | Meets only basic ISO standards |
summary
Choosing an oil-free air compressor for precision optical coating is the core decision to ensure optical performance and process stability. By strictly followingISO 8573-1:2010Standard and German Tüv “0” certification, such equipment can reduce coating defect rates and enhance product competitiveness. Leading manufacturers such as Shanghai Granklin Group use innovative technologies to promote industrial upgrading and provide global optical companies with compliance.SEMI standardClean compressed air solutions
