Co2 laser Focusing lens
| Material | diameter | focal length | Applicable power |
| senior Zinc selenide | Φ12 | 38.1 50.8 | Stamp machine |
| Φ18 | 38.1 50.8 63.5 76.2 101.6 | 50W-120W 80W-150W |
|
| Φ19.05 | 38.1 50.8 63.5 76.2 101.6 | ||
| Φ20 | 38.1 50.8 63.5 76.2 101.6 127 | ||
| Φ25.4 | 50.8 63.5 76.2 101.6 | 150W-300W | |
| Φ27.94 | 63.5 127 | ||
| Φ38.1 | 127 190.5 | ||
| ordinary Zinc selenide | Φ12 | 50.8 | Stamp machine |
| Φ18 | 50.8 63.5 76.2 101.6 | 50W-100W | |
| Φ19.05 | 38.1 50.8 63.5 76.2 101.6 | ||
| Φ20 | 38.1 50.8 63.5 76.2 101.6 | ||
| Gallium arsenide | Φ18 | 50.8 | 100W-150W |
| Φ19.05 | 50.8 63.5 | ||
| Φ20 | 50.8 63.5 76.2 |
Co2 laser reflex lens
| Material | diameter | thickness | Applicable power |
| K9 | Φ20 | 3 | 30-50W (Stamp machine) |
| molybdenum | Φ20 Φ25 Φ30 | 3 | 40W-150W |
| Φ38.1 | 5 | ||
| silicon | Φ19 Φ20 Φ25 Φ30 | 3 | 60W-300W |
| Φ38.1 | 6 |
In usual case , One Co2 laser engraving /cutting machine need 3 pieces of reflective Mirror, 1 piece of Focusing lens. Refer below picture.
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