H-K9L Double-Convex(DCX) Lenses, Uncoated/AR400-1650nm
Tuniu Optics double-convex lenses are made of H-K9L optical glass. Featuring a positive focal length, they consist of two convex surfaces with equal radii of curvature. They are widely applied in imaging relay systems and finite conjugate imaging applications. A higher conjugate ratio will introduce greater aberration. This lens type is ideal for scenarios where the object and image are located on opposite sides of the lens, with the conjugate ratio between 0.2 and 5. The focal length of a double-convex lens is calculated by the formula: f= (R1xR2)/((n-1)x(R2-R1)).
H-K9L optical glass is a high-performance material with broad spectral transmittance from 350 nm to 2000 nm. It offers high hardness, excellent physical and chemical resistance, and low bubble and inclusion content, making it an ideal substrate for a wide range of optical components. When the unique advantages of UV fused silica — such as high ultraviolet transmittance and low thermal expansion coefficient — are not required, H-K9L is the preferred choice.
H-K9L double-convex lenses are available uncoated or with three broadband anti-reflection coating options: VIS coating (400–700 nm), NIR coating (650–1050 nm), and SWIR coating (1000–1650 nm).
Parameters
| Material | H-K9L optical glass |
| Irregularity (P-V) | λ/4@632.8 nm |
| Design Wavelength | 587.6 nm |
| Surface Quality | 60-40 |
| Diameter Tolerance | + 0.0/- 0.1 mm |
| Center Thickness Tolerance | ± 0.2 mm |
| Focal Length Tolerance | ± 2 % |
| Centering Tolerance | < 3 arcmin |
| Refractive Index | 1.5168 |
| Clear aperture | > 90% |
| Abbe | v = 64.17 |
| Bevel | 0.2 mm X 45° |
| Coating | Uncoated, Ravg < 0.5%@400~700 nm, Ravg < 0.5%@650~1050 nm, Ravg < 0.5%@1000~1650 nm |
Model
| Dia.*, mm | Focal Length, mm | Coating |
| Φ12.5 | 12.5/25.0 | Uncoated, Ravg < 0.5%@400~700 nm, Ravg < 0.5%@650~1050 nm, Ravg < 0.5%@1000~1650 nm |
| Φ25 | 25/40 | |
| Φ40 | 40 | |
| Φ50 | 50 |
* Other Dia. Upon request. Up to φ100mm.