Deep-Focus Lens
Deep-Focus lenses are desinged for CO2/ YAG laser cutting and many other application.
By distributing a calculated fraction of the laser energy into a secondary (lower) focus, the lenses provide faster, cleaner cuts, with easier initiation and the elimination of sub-surface dross.
Deep-Focus lenses also allow much thicker materials to be cut at a given laser power. Additional advantages come from the fact that assist gas requirements are significantly reduced.
How Does Deep-Focus Lenses Work?
A Deep-Focus lens has two focal points. The inner portion of a laser beam is intercepted by a section of the lens, of diameter '2h', which has a longer focal length (FL) than the outer part of the lens. The 'basic focal length' is F. The difference in FL is ΔF.
This results is high energy density and increased localized temperature at both the upper and the lower foci.
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| Part No. | Material | Diameter (inch) | FL (inch) | ET |
|---|---|---|---|---|
| LZDF-1-2.5/3.5-ET4 | ZnSe | 1.0 | 2.5/3.5 | 4 |
| LZDF-1.1-5/7.5 | ZnSe | 1.1 | 5/7.5 | 4 |
| LZDF-1.5-5/7.5/10 | ZnSe | 1.5 | 5/7.5/10 | 6/7.4 |
| LZDF-2-5/7.5/10 | ZnSe | 2.0 | 5/7.5/10 | 8/9.6 |





