🔭Refractive astronomical telescope objective lens D=60mm

🔭Diameter: 62mm

🔭The focal length F: 300,360,400,500,600,700,800,900 mm Optional

🔭Coating: All-sided green film

🔭Combined image quality :1/4-1/8

🔭Diameter tolerance :+0/ -0.12mm

🔭Center thickness tolerance :±0.2mm

🔭Focal length tolerance :±0.1%

🔭Finish :60/40

🔭Eccentric :1'

🔭Note: two refraction double separation objective sets; Used for astronomical telescope objective and star finder.