Calcium Fluoride(CaF₂) Double Concave (DCV) Lenses, Uncoated/AR3~5μm
Calcium Fluoride (CaF₂) Double Concave (DCV) Lenses are high-performance optical components manufactured from premium CaF₂ substrate. Featuring a broad transmission spectrum of 180 nm to 8.0 μm, CaF₂ offers high laser damage threshold, low fluorescence and excellent optical homogeneity. This material is relatively soft and susceptible to surface scratching, and is widely used for laser collimation and as a substrate for lenses, windows and other optical elements.
Double concave lenses feature a negative focal length with two symmetric concave surfaces, designed to diverge light beams for beam expansion, projection systems and focal length extension in optical setups. Tuniu Optics provides CaF₂ double concave lenses in a full range of sizes and focal lengths, available in uncoated and broadband anti-reflection coated versions optimized for the 3–5 μm IR1 infrared band to satisfy diverse application scenarios. Custom specifications are available upon request.
Parameters
| Material | CaF2 single crystal |
| Design Wavelength | 587.6 nm |
| Diameter Tolerance | + 0.0/ -0.1 mm |
| Center Thickness Tolerance | ± 0.1 mm |
| Focal Length Tolerance(EFL) | ± 1% |
| Centering Tolerance | < 3 arcmin |
| Surface Quality | 60-40 |
| Bevel | 0.2 mm X 45° |
| Coating | Uncoated, Ravg < 1.5%@3~5 μm |
Model
| Dia., mm | Coating | EFL, mm |
| 12.7 | Uncoated/Double-Sided-AR@3~5 μm | -15.00/-25.00 |
| 25.4 | Uncoated/Double-Sided-AR@3~5 μm | -30.00/-50.00 |

