Material:optical glass,fused silica,CaF2 and optical crystalSize:10mm-200mmDimension tolerance:±0.2mm　Angle tolerance:±5arc sec—5arc minOptical parallelism:3arc minFlatness:λ／10—1λSurface quality:60—40scratch and digCoating

Material:optical glass,fused silica,CaF2 and optical crystalSize:10mm-200mmDimension tolerance:±0.2mm　Angle tolerance:±30arc sec—5 arc minOptical parallelism:2arc secFlatness:λ／10—1λSurface quality:40—20scratch and diClear

Material:optical glass,fused silica,CaF2 and optical crystalSize:5mm-100mmDimension tolerance:±0.2mm　Angle tolerance:30arc sec—3 arc minOptical parallelism:10arc sec Flatness:λ／10—1λ Surface quality:60—40scratch and dig Clea

Material:optical glass,fused silica,CaF2 and optical crystalSize:8mm-100mmDimension tolerance:±0.15mm　Angle tolerance:±3 arc minOptical paralellism:3 arc minFlatness:λ／10—1λSurface quality:60—40scratch and digClear aperture:9

Material:optical glass,fused silica, Size:4mm-100mmDimension tolerance:±0.2mm　Angle tolerance:±30arc secOptical parallelism:10arc secFlatness:λ／2—λ/8Surface Clear aperture:90％ quality:60

Material:BK7,UV-grade fused silicaParaxial focal length:±5mm—±3000mm±1%Length:2mm—300mm±1%Width:2mm—200mm±1%Surface quality:60-40scratch and digSurface Figure:λ／4,λ/2Centration:3arc minThickness Tolerance:±0.20mmClear Apertur

Material:BK7,UV-grade fused silicaParaxial focal length:±5mm—±3000mm±1%Length:2mm—300mm±1%Width:2mm—200mm±1%Surface quality:60-40scratch and digSurface Figure:λ／4,λ/2Centration:3arc minThickness Tolerance:±0.20mmClear Aperture

Material:BK7,UV-grade fused silicaParaxial focal length:±5mm—±3000mm±1%Length:2mm—300mm±1%Width:2mm—200mm±1%Surface quality:60-40scratch and digSurface Figure:λ／4,λ/2Centration:3arc minThickness Tolerance:±0.20mmClear Apertur

It used to Converge parallel light, or make light source into parallel light . Material:BK7,UV-grade fused silicaSize:3mm-220mmThickness Tolerance:±0.1mmCentration:3 arc min　Surface figure:1/4λSurface quality:60â

They have a negative focal length, is used to diverge a parallel light beam.Material:BK7,UV-grade fused silicaSize:3mm-220mmThickness Tolerance:±0.1mmCentration:3 arc min　Surface figure:1λSurface quality:60—40scratch and digClear aperture: