Plano Convex Lenses
Plano-Convex Lenses
Plano-convex lenses (PCX lenses) feature one flat surface and one outward-curving surface, providing positive focal length for light collimation and simple imaging. These lenses excel in infinite conjugate systems and laser applications where the curved surface faces the collimated beam. Star-Optics manufactures plano-convex lenses from optical glass, fused silica, and sapphire, with custom diameters from 2mm to 300mm and anti-reflective coatings for your wavelength range.
When to Orient the Curved Surface
Proper orientation maximizes performance. Position the curved surface toward the collimated light or longer conjugate distance to minimize spherical aberration. In laser systems, the curved surface should face the collimated beam. For imaging applications where object and image distances differ significantly, place the curved surface toward infinity or the longer working distance.
Material Properties and Selection
Index of refraction goes from 1.4 (fluorides) to 4.0 (germanium), which affects the focal length. BK7 glass (n=1.517) works for visible light applications. Fused silica lets UV light pass through. Germanium works for infrared light from 2-16μm.
Abbe number shows how much the material separates colors. Higher numbers (above 55, crown glass) separate colors less. Lower numbers (below 50, flint glass) separate colors more. For single-color laser applications, Abbe number is less important than for regular imaging.
Laser damage threshold is the maximum power level before the surface gets damaged. High-power applications need materials and coatings that can handle your laser power. Fused silica usually resists laser damage better than regular optical glass.
Manufacturing Capabilities
| Parameter | Factory Standard | Manufacturing Limit |
|---|---|---|
| Material | Optical glass, fused silica, sapphire | — |
| Diameter | 2 mm – 300 mm | — |
| Diameter Tolerance | ±0.05 mm | ±0.01 mm |
| Center Thickness Tolerance | ±0.05 mm | ±0.01 mm |
| Radius Tolerance | ±0.3% | ±0.2% |
| Surface Quality | 40-20 | 10-5 |
| Surface Accuracy | λ | λ/20 |
| Irregularity | λ/4 | < λ/10 |
| Centration | 3 arc min | 1 arc min |
Custom Manufacturing
We manufacture plano-convex lenses tailored to your focal length, diameter, and surface accuracy requirements. Our optical engineering team optimizes lens specifications for your system constraints—working distance, numerical aperture, wavelength range, and environmental conditions.
