Fig. 1. Common vacuum optical cabin

Fig. 2. Vacuum optical cabin without negative pressure

Fig. 3. Numerical analysis model of optical cabin

Fig. 4. Numerical analysis results of common vacuum optical cabin

Fig. 5. Numerical analysis results of vacuum optical cabin without negative pressure

Fig. 6. Metal bellows

Fig. 7. Structure diagram of vacuum negative pressure compensator

Fig. 8. Operating principle of vacuum negative pressure compensator

Fig. 9. Vacuum optical cabin without negative pressure

Fig. 10. Principle of vacuum negative pressure stress automatic balance

Fig. 11. Stress compensation principle of thermal expansion and cold contraction

Fig. 12. Practical application of stress compensation principle of thermal expansion and cold contraction